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Luppi AI, Rosas FE, Noonan MP, Mediano PAM, Kringelbach ML, Carhart-Harris RL, Stamatakis EA, Vernon AC, Turkheimer FE. Oxygen and the Spark of Human Brain Evolution: Complex Interactions of Metabolism and Cortical Expansion across Development and Evolution. Neuroscientist 2024; 30:173-198. [PMID: 36476177 DOI: 10.1177/10738584221138032] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Scientific theories on the functioning and dysfunction of the human brain require an understanding of its development-before and after birth and through maturation to adulthood-and its evolution. Here we bring together several accounts of human brain evolution by focusing on the central role of oxygen and brain metabolism. We argue that evolutionary expansion of human transmodal association cortices exceeded the capacity of oxygen delivery by the vascular system, which led these brain tissues to rely on nonoxidative glycolysis for additional energy supply. We draw a link between the resulting lower oxygen tension and its effect on cytoarchitecture, which we posit as a key driver of genetic developmental programs for the human brain-favoring lower intracortical myelination and the presence of biosynthetic materials for synapse turnover. Across biological and temporal scales, this protracted capacity for neural plasticity sets the conditions for cognitive flexibility and ongoing learning, supporting complex group dynamics and intergenerational learning that in turn enabled improved nutrition to fuel the metabolic costs of further cortical expansion. Our proposed model delineates explicit mechanistic links among metabolism, molecular and cellular brain heterogeneity, and behavior, which may lead toward a clearer understanding of brain development and its disorders.
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Affiliation(s)
- Andrea I Luppi
- Department of Clinical Neurosciences and Division of Anaesthesia, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Leverhulme Centre for the Future of Intelligence, University of Cambridge, Cambridge, UK
- The Alan Turing Institute, London, UK
| | - Fernando E Rosas
- Department of Informatics, University of Sussex, Brighton, UK
- Centre for Psychedelic Research, Department of Brain Science, Imperial College London, London, UK
- Centre for Complexity Science, Imperial College London, London, UK
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK
| | - MaryAnn P Noonan
- Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Pedro A M Mediano
- Department of Psychology, University of Cambridge, Cambridge, UK
- Department of Psychology, Queen Mary University of London, London, UK
- Department of Computing, Imperial College London, London, UK
| | - Morten L Kringelbach
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, UK
- Center for Music in the Brain, Aarhus University, Aarhus, Denmark
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Robin L Carhart-Harris
- Psychedelics Division-Neuroscape, Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Emmanuel A Stamatakis
- Department of Clinical Neurosciences and Division of Anaesthesia, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Anthony C Vernon
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Lord LD, Carletti T, Fernandes H, Turkheimer FE, Expert P. Altered dynamical integration/segregation balance during anesthesia-induced loss of consciousness. Front Netw Physiol 2023; 3:1279646. [PMID: 38116461 PMCID: PMC10728865 DOI: 10.3389/fnetp.2023.1279646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 11/20/2023] [Indexed: 12/21/2023]
Abstract
In recent years, brain imaging studies have begun to shed light on the neural correlates of physiologically-reversible altered states of consciousness such as deep sleep, anesthesia, and psychedelic experiences. The emerging consensus is that normal waking consciousness requires the exploration of a dynamical repertoire enabling both global integration i.e., long-distance interactions between brain regions, and segregation, i.e., local processing in functionally specialized clusters. Altered states of consciousness have notably been characterized by a tipping of the integration/segregation balance away from this equilibrium. Historically, functional MRI (fMRI) has been the modality of choice for such investigations. However, fMRI does not enable characterization of the integration/segregation balance at sub-second temporal resolution. Here, we investigated global brain spatiotemporal patterns in electrocorticography (ECoG) data of a monkey (Macaca fuscata) under either ketamine or propofol general anesthesia. We first studied the effects of these anesthetics from the perspective of band-specific synchronization across the entire ECoG array, treating individual channels as oscillators. We further aimed to determine whether synchrony within spatially localized clusters of oscillators was differently affected by the drugs in comparison to synchronization over spatially distributed subsets of ECoG channels, thereby quantifying changes in integration/segregation balance on physiologically-relevant time scales. The findings reflect global brain dynamics characterized by a loss of long-range integration in multiple frequency bands under both ketamine and propofol anesthesia, most pronounced in the beta (13-30 Hz) and low-gamma bands (30-80 Hz), and with strongly preserved local synchrony in all bands.
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Affiliation(s)
- Louis-David Lord
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Institut Méditerranéen de Recherches Avancées (IMéRA), Aix-Marseille Université, Marseille, France
| | - Timoteo Carletti
- Institut Méditerranéen de Recherches Avancées (IMéRA), Aix-Marseille Université, Marseille, France
- Department of Mathematics and Namur Institute for Complex Systems (naXys), University of Namur, Namur, Belgium
| | - Henrique Fernandes
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Institut Méditerranéen de Recherches Avancées (IMéRA), Aix-Marseille Université, Marseille, France
- Centre for Music in the Brain, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Paul Expert
- Institut Méditerranéen de Recherches Avancées (IMéRA), Aix-Marseille Université, Marseille, France
- Global Business School for Health, University College London, London, United Kingdom
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Singh N, MacNicol E, DiPasquale O, Randall K, Lythgoe D, Mazibuko N, Simmons C, Selvaggi P, Stephenson S, Turkheimer FE, Cash D, Zelaya F, Colasanti A. The effects of acute Methylene Blue administration on cerebral blood flow and metabolism in humans and rats. J Cereb Blood Flow Metab 2023; 43:95-105. [PMID: 36803299 PMCID: PMC10638993 DOI: 10.1177/0271678x231157958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 11/09/2022] [Accepted: 12/26/2022] [Indexed: 02/23/2023]
Abstract
Methylene Blue (MB) is a brain-penetrating drug with putative neuroprotective, antioxidant and metabolic enhancing effects. In vitro studies suggest that MB enhances mitochondrial complexes activity. However, no study has directly assessed the metabolic effects of MB in the human brain. We used in vivo neuroimaging to measure the effect of MB on cerebral blood flow (CBF) and brain metabolism in humans and in rats. Two doses of MB (0.5 and 1 mg/kg in humans; 2 and 4 mg/kg in rats; iv) induced reductions in global cerebral blood flow (CBF) in humans (F(1.74, 12.17)5.82, p = 0.02) and rats (F(1,5)26.04, p = 0.0038). Human cerebral metabolic rate of oxygen (CMRO2) was also significantly reduced (F(1.26, 8.84)8.01, p = 0.016), as was the rat cerebral metabolic rate of glucose (CMRglu) (t = 2.6(16) p = 0.018). This was contrary to our hypothesis that MB will increase CBF and energy metrics. Nevertheless, our results were reproducible across species and dose dependent. One possible explanation is that the concentrations used, although clinically relevant, reflect MB's hormetic effects, i.e., higher concentrations produce inhibitory rather than augmentation effects on metabolism. Additionally, here we used healthy volunteers and healthy rats with normal cerebral metabolism where MB's ability to enhance cerebral metabolism might be limited.
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Affiliation(s)
- Nisha Singh
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Eilidh MacNicol
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Ottavia DiPasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Karen Randall
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - David Lythgoe
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Ndabezinhle Mazibuko
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Camilla Simmons
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Pierluigi Selvaggi
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Stephanie Stephenson
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Alessandro Colasanti
- Department of Clinical Neuroscience and Neuroimaging, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
- Centre for Affective Disorders, Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
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Dezhina Z, Smallwood J, Xu T, Turkheimer FE, Moran RJ, Friston KJ, Leech R, Fagerholm ED. Establishing brain states in neuroimaging data. PLoS Comput Biol 2023; 19:e1011571. [PMID: 37844124 PMCID: PMC10602380 DOI: 10.1371/journal.pcbi.1011571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 10/26/2023] [Accepted: 10/04/2023] [Indexed: 10/18/2023] Open
Abstract
The definition of a brain state remains elusive, with varying interpretations across different sub-fields of neuroscience-from the level of wakefulness in anaesthesia, to activity of individual neurons, voltage in EEG, and blood flow in fMRI. This lack of consensus presents a significant challenge to the development of accurate models of neural dynamics. However, at the foundation of dynamical systems theory lies a definition of what constitutes the 'state' of a system-i.e., a specification of the system's future. Here, we propose to adopt this definition to establish brain states in neuroimaging timeseries by applying Dynamic Causal Modelling (DCM) to low-dimensional embedding of resting and task condition fMRI data. We find that ~90% of subjects in resting conditions are better described by first-order models, whereas ~55% of subjects in task conditions are better described by second-order models. Our work calls into question the status quo of using first-order equations almost exclusively within computational neuroscience and provides a new way of establishing brain states, as well as their associated phase space representations, in neuroimaging datasets.
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Affiliation(s)
- Zalina Dezhina
- Department of Neuroimaging, King’s College London, United Kingdom
| | | | - Ting Xu
- Child Mind Institute, New York, United States of America
| | | | - Rosalyn J. Moran
- Department of Neuroimaging, King’s College London, United Kingdom
| | | | - Robert Leech
- Department of Neuroimaging, King’s College London, United Kingdom
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Selvaggi P, Jauhar S, Kotoula V, Pepper F, Veronese M, Santangelo B, Zelaya F, Turkheimer FE, Mehta MA, Howes OD. Reduced cortical cerebral blood flow in antipsychotic-free first-episode psychosis and relationship to treatment response. Psychol Med 2023; 53:5235-5245. [PMID: 36004510 PMCID: PMC10476071 DOI: 10.1017/s0033291722002288] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 06/27/2022] [Accepted: 07/04/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND Altered cerebral blood flow (CBF) has been found in people at risk for psychosis, with first-episode psychosis (FEP) and with chronic schizophrenia (SCZ). Studies using arterial spin labelling (ASL) have shown reduction of cortical CBF and increased subcortical CBF in SCZ. Previous studies have investigated CBF using ASL in FEP, reporting increased CBF in striatum and reduced CBF in frontal cortex. However, as these people were taking antipsychotics, it is unclear whether these changes are related to the disorder or antipsychotic treatment and how they relate to treatment response. METHODS We examined CBF in FEP free from antipsychotic medication (N = 21), compared to healthy controls (N = 22). Both absolute and relative-to-global CBF were assessed. We also investigated the association between baseline CBF and treatment response in a partially nested follow-up study (N = 14). RESULTS There was significantly lower absolute CBF in frontal cortex (Cohen's d = 0.84, p = 0.009) and no differences in striatum or hippocampus. Whole brain voxel-wise analysis revealed widespread cortical reductions in absolute CBF in large cortical clusters that encompassed occipital, parietal and frontal cortices (Threshold-Free Cluster Enhancement (TFCE)-corrected <0.05). No differences were found in relative-to-global CBF in the selected region of interests and in voxel-wise analysis. Relative-to-global frontal CBF was correlated with percentage change in total Positive and Negative Syndrome Scale after antipsychotic treatment (r = 0.67, p = 0.008). CONCLUSIONS These results show lower cortical absolute perfusion in FEP prior to starting antipsychotic treatment and suggest relative-to-global frontal CBF as assessed with magnetic resonance imaging could potentially serve as a biomarker for antipsychotic response.
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Affiliation(s)
- Pierluigi Selvaggi
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Azienda Ospedaliero-Universitaria Consorziale Policlinico di Bari, Bari, Italy
| | - Sameer Jauhar
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Early Intervention Psychosis Clinical Academic Group, South London & Maudsley NHS Foundation Trust, London, UK
| | - Vasileia Kotoula
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Fiona Pepper
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Barbara Santangelo
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mitul A. Mehta
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Oliver D. Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC London Institute of Medical Sciences, Hammersmith Hospital, London W12 0NN, UK
- Faculty of Medicine, Institute of Clinical Sciences (ICS), Imperial College London, Du Cane Road, London W12 0NN, UK
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Williams MR, Macdonald CM, Turkheimer FE. Histological examination of choroid plexus epithelia changes in schizophrenia. Brain Behav Immun 2023; 111:292-297. [PMID: 37150267 DOI: 10.1016/j.bbi.2023.04.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 04/14/2023] [Accepted: 04/30/2023] [Indexed: 05/09/2023] Open
Abstract
BACKGROUND The choroid plexus (CP) produces and secretes most of the cerebrospinal fluid (CSF) of the central nervous system. The CP is suggested to be regulated by descending neurons and by circulating factors and is involved in the interaction between central and peripheral inflammation. Quantitative imaging has demonstrated volumetric CP changes in psychosis, schizophrenia and depression. This study histologically examines CP epithelial cell morphology in these illnesses to identify the biological source of such volumetric changes. METHODS Formalin-fixed paraffin-embedded (FFPE) blocks were obtained bilaterally from the lateral ventricles of 13 cases of sex- and age-matched brains from each of schizophrenia (SZ) with psychosis, major depressive disorder (MDD) and matched controls (NPD). FFPE blocks were sectioned at 7 μm and routinely stained for H&E. Morphological analysis of 180 CP epithelia/case was conducted blindly on digital images collected at x600 magnification. Calcification was assessed in all CP regions manually. RESULTS Analysis with a General Linear Model demonstrated a significant effect of diagnosis on somal width (p = 0.006, R2 = 0.33 R2(adj) = 0.25) demonstrating increased somal width in SZ without psychotic medication versus controls (p = 0.032), but not in medicated SZ cases. No effects were observed in calcification. DISCUSSION The epithelial cells that were examined were attached to the CP fibrous surface, so width expansion describes the primary methods for these cells to expand with adherence to this surface in SZ. The interaction of antipsychotic medication and diagnosis demonstrates that this is an illness-specific change mediated through the DA-system with likely neuronal origin. CP alterations were not found in MDD where they are instead generally associated with heightened allostatic load that was unknown in this cohort.
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Affiliation(s)
- M R Williams
- Segmentum Analysis, St John's Innovation Park, Cambridge Science Park, UK
| | | | - F E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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Turkheimer FE, Veronese M, Mondelli V, Cash D, Pariante CM. Sickness behaviour and depression: An updated model of peripheral-central immunity interactions. Brain Behav Immun 2023; 111:202-210. [PMID: 37076054 DOI: 10.1016/j.bbi.2023.03.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/15/2023] [Accepted: 03/26/2023] [Indexed: 04/21/2023] Open
Abstract
Current research into mood disorders indicates that circulating immune mediators participating in the pathophysiology of chronic somatic disorders have potent influences on brain function. This paradigm has brought to the fore the use of anti-inflammatory therapies as adjunctive to standard antidepressant therapy to improve treatment efficacy, particularly in subjects that do not respond to standard medication. Such new practice requires biomarkers to tailor these new therapies to those most likely to benefit but also validated mechanisms of action describing the interaction between peripheral immunity and brain function to optimize target intervention. These mechanisms are generally studied in preclinical models that try to recapitulate the human disease, MDD, through peripherally induced sickness behaviour. In this proposal paper, after an appraisal of the data in rodent models and their adherence to the data in clinical cohorts, we put forward a modified model of periphery-brain interactions that goes beyond the currently established view of microglia cells as the drivers of depression. Instead, we suggest that, for most patients with mild levels of peripheral inflammation, brain barriers are the primary actors in the pathophysiology of the disease and in treatment resistance. We then highlight data gaps in this proposal and suggest novel lines of research.
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Affiliation(s)
- Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Department of Information Engineering, University of Padova, Padova, Italy
| | - Valeria Mondelli
- Department of Psychological Medicine, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Carmine M Pariante
- Department of Psychological Medicine, Institute of Psychiatry, Psychology, and Neuroscience, King's College London, London, United Kingdom
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Hancock F, Rosas FE, McCutcheon RA, Cabral J, Dipasquale O, Turkheimer FE. Metastability as a candidate neuromechanistic biomarker of schizophrenia pathology. PLoS One 2023; 18:e0282707. [PMID: 36952467 PMCID: PMC10035891 DOI: 10.1371/journal.pone.0282707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 02/21/2023] [Indexed: 03/25/2023] Open
Abstract
The disconnection hypothesis of schizophrenia proposes that symptoms of the disorder arise as a result of aberrant functional integration between segregated areas of the brain. The concept of metastability characterizes the coexistence of competing tendencies for functional integration and functional segregation in the brain, and is therefore well suited for the study of schizophrenia. In this study, we investigate metastability as a candidate neuromechanistic biomarker of schizophrenia pathology, including a demonstration of reliability and face validity. Group-level discrimination, individual-level classification, pathophysiological relevance, and explanatory power were assessed using two independent case-control studies of schizophrenia, the Human Connectome Project Early Psychosis (HCPEP) study (controls n = 53, non-affective psychosis n = 82) and the Cobre study (controls n = 71, cases n = 59). In this work we extend Leading Eigenvector Dynamic Analysis (LEiDA) to capture specific features of dynamic functional connectivity and then implement a novel approach to estimate metastability. We used non-parametric testing to evaluate group-level differences and a naïve Bayes classifier to discriminate cases from controls. Our results show that our new approach is capable of discriminating cases from controls with elevated effect sizes relative to published literature, reflected in an up to 76% area under the curve (AUC) in out-of-sample classification analyses. Additionally, our new metric showed explanatory power of between 81-92% for measures of integration and segregation. Furthermore, our analyses demonstrated that patients with early psychosis exhibit intermittent disconnectivity of subcortical regions with frontal cortex and cerebellar regions, introducing new insights about the mechanistic bases of these conditions. Overall, these findings demonstrate reliability and face validity of metastability as a candidate neuromechanistic biomarker of schizophrenia pathology.
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Affiliation(s)
- Fran Hancock
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, United Kingdom
| | - Fernando E. Rosas
- Department of Informatics, University of Sussex, Brighton, United Kingdom
- Centre for Psychedelic Research, Department of Brain Science, Imperial College London, London, United Kingdom
- Centre for Complexity Science, Imperial College London, London, United Kingdom
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, United Kingdom
| | - Robert A. McCutcheon
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, De Crespigny Park, London, United Kingdom
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Joana Cabral
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
- Life and Health Sciences Research Institute School of Medicine, University of Minho, Braga, Portugal
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, United Kingdom
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London, United Kingdom
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9
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Fagerholm ED, Dezhina Z, Moran RJ, Turkheimer FE, Leech R. A primer on entropy in neuroscience. Neurosci Biobehav Rev 2023; 146:105070. [PMID: 36736445 DOI: 10.1016/j.neubiorev.2023.105070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/16/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Entropy is not just a property of a system - it is a property of a system and an observer. Specifically, entropy is a measure of the amount of hidden information in a system that arises due to an observer's limitations. Here we provide an account of entropy from first principles in statistical mechanics with the aid of toy models of neural systems. Specifically, we describe the distinction between micro and macrostates in the context of simplified binary-state neurons and the characteristics of entropy required to capture an associated measure of hidden information. We discuss the origin of the mathematical form of entropy via the indistinguishable re-arrangements of discrete-state neurons and show the way in which the arguments are extended into a phase space description for continuous large-scale neural systems. Finally, we show the ways in which limitations in neuroimaging resolution, as represented by coarse graining operations in phase space, lead to an increase in entropy in time as per the second law of thermodynamics. It is our hope that this primer will support the increasing number of studies that use entropy as a way of characterising neuroimaging timeseries and of making inferences about brain states.
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Affiliation(s)
- Erik D Fagerholm
- Department of Neuroimaging, King's College London, United Kingdom.
| | - Zalina Dezhina
- Department of Neuroimaging, King's College London, United Kingdom
| | - Rosalyn J Moran
- Department of Neuroimaging, King's College London, United Kingdom
| | | | - Robert Leech
- Department of Neuroimaging, King's College London, United Kingdom
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10
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Turkheimer FE, Liu J, Fagerholm ED, Dazzan P, Loggia ML, Bettelheim E. The art of pain: A quantitative color analysis of the self-portraits of Frida Kahlo. Front Hum Neurosci 2022; 16:1000656. [PMID: 36118965 PMCID: PMC9478482 DOI: 10.3389/fnhum.2022.1000656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/17/2022] [Indexed: 11/19/2022] Open
Abstract
Frida Kahlo (1907–1954) was a Mexican artist who is remembered for her self-portraits, pain and passion, and bold, vibrant colors. This work aims to use her life story and her artistic production in a longitudinal study to examine with quantitative tools the effects of physical and emotional pain (rage) on artistic expression. Kahlo suffered from polio as a child, was involved in a bus accident as a teenager where she suffered multiple fractures of her spine and had 30 operations throughout her lifetime. She also had a tempestuous relationship with her painter husband, Diego Rivera. Her physical and personal troubles however became the texture of her vivid visual vocabulary—usually expressed through the depiction of Mexican and indigenous culture or the female experience and form. We applied color analysis to a series of Frida's self-portraits and revealed a very strong association of physical pain and emotional rage with low wavelength colors (red and yellow), indicating that the expression of her ailments was, consciously or not, achieved by increasing the perceived luminance of the canvas. Further quantitative analysis that used the fractal dimension identified “The broken column” as the portrait with higher compositional complexity, which matches previous critical acclaim of this portrait as the climax of her art. These results confirm the ability of color analysis to extract emotional and cognitive features from artistic work. We suggest that these tools could be used as markers to support artistic and creative interventions in mental health.
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Affiliation(s)
- Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- *Correspondence: Federico E. Turkheimer
| | - Jingyi Liu
- Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Erik D. Fagerholm
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Paola Dazzan
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Marco L. Loggia
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Massachusetts General Hospital, Boston, MA, United States
| | - Eric Bettelheim
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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11
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Hancock F, Cabral J, Luppi AI, Rosas FE, Mediano PAM, Dipasquale O, Turkheimer FE. Metastability, fractal scaling, and synergistic information processing: what phase relationships reveal about intrinsic brain activity. Neuroimage 2022; 259:119433. [PMID: 35781077 PMCID: PMC9339663 DOI: 10.1016/j.neuroimage.2022.119433] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 06/25/2022] [Accepted: 06/29/2022] [Indexed: 12/21/2022] Open
Abstract
Spatiotemporal patterns of phase-locking tend to be time-invariant. Global metastability is representative and stable in a cohort of heathy young adults. dFC characteristics are in general unique to any fMRI acquisition. Dynamical and informational complexity are interrelated. Complexity science contributes to a coherent description of brain dynamics.
Dynamic functional connectivity (dFC) in resting-state fMRI holds promise to deliver candidate biomarkers for clinical applications. However, the reliability and interpretability of dFC metrics remain contested. Despite a myriad of methodologies and resulting measures, few studies have combined metrics derived from different conceptualizations of brain functioning within the same analysis - perhaps missing an opportunity for improved interpretability. Using a complexity-science approach, we assessed the reliability and interrelationships of a battery of phase-based dFC metrics including tools originating from dynamical systems, stochastic processes, and information dynamics approaches. Our analysis revealed novel relationships between these metrics, which allowed us to build a predictive model for integrated information using metrics from dynamical systems and information theory. Furthermore, global metastability - a metric reflecting simultaneous tendencies for coupling and decoupling - was found to be the most representative and stable metric in brain parcellations that included cerebellar regions. Additionally, spatiotemporal patterns of phase-locking were found to change in a slow, non-random, continuous manner over time. Taken together, our findings show that the majority of characteristics of resting-state fMRI dynamics reflect an interrelated dynamical and informational complexity profile, which is unique to each acquisition. This finding challenges the interpretation of results from cross-sectional designs for brain neuromarker discovery, suggesting that individual life-trajectories may be more informative than sample means.
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Affiliation(s)
- Fran Hancock
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Joana Cabral
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Portugal
| | - Andrea I Luppi
- Division of Anaesthesia, School of Clinical Medicine, University of Cambridge; Department of Clinical Neurosciences, University of Cambridge; Leverhulme Centre for the Future of Intelligence, University of Cambridge; Alan Turing Institute, London, UK
| | - Fernando E Rosas
- Centre for Psychedelic Research, Department of Brain Science, Imperial College London, London SW7 2DD; Data Science Institute, Imperial College London, London SW7 2AZ; Centre for Complexity Science, Imperial College London, London SW7 2AZ
| | - Pedro A M Mediano
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB; Department of Psychology, Queen Mary University of London, London E1 4NS
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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12
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Hancock F, Rosas FE, Mediano PAM, Luppi AI, Cabral J, Dipasquale O, Turkheimer FE. May the 4C's be with you: an overview of complexity-inspired frameworks for analysing resting-state neuroimaging data. J R Soc Interface 2022; 19:20220214. [PMID: 35765805 PMCID: PMC9240685 DOI: 10.1098/rsif.2022.0214] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 06/09/2022] [Indexed: 11/12/2022] Open
Abstract
Competing and complementary models of resting-state brain dynamics contribute to our phenomenological and mechanistic understanding of whole-brain coordination and communication, and provide potential evidence for differential brain functioning associated with normal and pathological behaviour. These neuroscientific theories stem from the perspectives of physics, engineering, mathematics and psychology and create a complicated landscape of domain-specific terminology and meaning, which, when used outside of that domain, may lead to incorrect assumptions and conclusions within the neuroscience community. Here, we review and clarify the key concepts of connectivity, computation, criticality and coherence-the 4C's-and outline a potential role for metastability as a common denominator across these propositions. We analyse and synthesize whole-brain neuroimaging research, examined through functional magnetic imaging, to demonstrate that complexity science offers a principled and integrated approach to describe, and potentially understand, macroscale spontaneous brain functioning.
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Affiliation(s)
- Fran Hancock
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Fernando E. Rosas
- Centre for Psychedelic Research, Department of Brain Science, Imperial College London, London SW7 2DD, UK
- Data Science Institute, Imperial College London, London SW7 2AZ, UK
- Centre for Complexity Science, Imperial College London, London SW7 2AZ, UK
| | - Pedro A. M. Mediano
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, UK
- Department of Psychology, Queen Mary University of London, London E1 4NS, UK
| | - Andrea I. Luppi
- Division of Anaesthesia, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Leverhulme Centre for the Future of Intelligence, University of Cambridge, Cambridge, UK
- Alan Turing Institute, London, UK
| | - Joana Cabral
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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13
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Turkheimer FE, Selvaggi P, Mehta MA, Veronese M, Zelaya F, Dazzan P, Vernon AC. Corrigendum to: Normalizing the Abnormal: Do Antipsychotic Drugs Push the Cortex Into an Unsustainable Metabolic Envelope? Schizophr Bull 2022; 48:721. [PMID: 32065235 PMCID: PMC9077407 DOI: 10.1093/schbul/sbz139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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MacNicol E, Wright P, Kim E, Brusini I, Esteban O, Simmons C, Turkheimer FE, Cash D. Age-Specific Adult Rat Brain MRI Templates and Tissue Probability Maps. Front Neuroinform 2022; 15:669049. [PMID: 35069163 PMCID: PMC8777032 DOI: 10.3389/fninf.2021.669049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 12/03/2021] [Indexed: 11/30/2022] Open
Abstract
Age-specific resources in human MRI mitigate processing biases that arise from structural changes across the lifespan. There are fewer age-specific resources for preclinical imaging, and they only represent developmental periods rather than adulthood. Since rats recapitulate many facets of human aging, it was hypothesized that brain volume and each tissue's relative contribution to total brain volume would change with age in the adult rat. Data from a longitudinal study of rats at 3, 5, 11, and 17 months old were used to test this hypothesis. Tissue volume was estimated from high resolution structural images using a priori information from tissue probability maps. However, existing tissue probability maps generated inaccurate gray matter probabilities in subcortical structures, particularly the thalamus. To address this issue, gray matter, white matter, and CSF tissue probability maps were generated by combining anatomical and signal intensity information. The effects of age on volumetric estimations were then assessed with mixed-effects models. Results showed that herein estimation of gray matter volumes better matched histological evidence, as compared to existing resources. All tissue volumes increased with age, and the tissue proportions relative to total brain volume varied across adulthood. Consequently, a set of rat brain templates and tissue probability maps from across the adult lifespan is released to expand the preclinical MRI community's fundamental resources.
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Affiliation(s)
- Eilidh MacNicol
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Paul Wright
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences & Medicine, King's College London, London, United Kingdom
| | - Eugene Kim
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Irene Brusini
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm, Sweden
- Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden
| | - Oscar Esteban
- Department of Psychology, Stanford University, Stanford, CA, United States
- Department of Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Camilla Simmons
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
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15
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Althubaity N, Schubert J, Martins D, Yousaf T, Nettis MA, Mondelli V, Pariante C, Harrison NA, Bullmore ET, Dima D, Turkheimer FE, Veronese M. Choroid plexus enlargement is associated with neuroinflammation and reduction of blood brain barrier permeability in depression. Neuroimage Clin 2021; 33:102926. [PMID: 34972034 PMCID: PMC8718974 DOI: 10.1016/j.nicl.2021.102926] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/08/2021] [Accepted: 12/21/2021] [Indexed: 12/24/2022]
Abstract
BACKGROUND Recent studies have shown that choroid plexuses (CP) may be involved in the neuro-immune axes, playing a role in the interaction between the central and peripheral inflammation. Here we aimed to investigate CP volume alterations in depression and their associations with inflammation. METHODS 51 depressed participants (HDRS score > 13) and 25 age- and sex-matched healthy controls (HCs) from the Wellcome Trust NIMA consortium were re-analysed for the study. All the participants underwent full peripheral cytokine profiling and simultaneous [11C]PK11195 PET/structural MRI imaging for measuring neuroinflammation and CP volume respectively. RESULTS We found a significantly greater CP volume in depressed subjects compared to HCs (t(76) = +2.17) that was positively correlated with [11C]PK11195 PET binding in the anterior cingulate cortex (r = 0.28, p = 0.02), prefrontal cortex (r = 0.24, p = 0.04), and insular cortex (r = 0.24, p = 0.04), but not with the peripheral inflammatory markers: CRP levels (r = 0.07, p = 0.53), IL-6 (r = -0.08, p = 0.61), and TNF-α (r = -0.06, p = 0.70). The CP volume correlated with the [11C]PK11195 PET binding in CP (r = 0.34, p = 0.005). Integration of transcriptomic data from the Allen Human Brain Atlas with the brain map depicting the correlations between CP volume and PET imaging found significant gene enrichment for several pathways involved in neuroinflammatory response. CONCLUSION This result supports the hypothesis that changes in brain barriers may cause reduction in solute exchanges between blood and CSF, disturbing the brain homeostasis and ultimately contributing to inflammation in depression. Given that CP anomalies have been recently detected in other brain disorders, these results may not be specific to depression and might extend to other conditions with a peripheral inflammatory component.
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Affiliation(s)
- Noha Althubaity
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Department of Radiological Sciences, College of Applied Medical Science, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
| | - Julia Schubert
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Daniel Martins
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Tayyabah Yousaf
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Maria A Nettis
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Valeria Mondelli
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Carmine Pariante
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Neil A Harrison
- Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK; Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, UK
| | - Edward T Bullmore
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK; Immuno-Psychiatry, Immuno-Inflammation Therapeutic Area Unit, GlaxoSmithKline R&D, Stevenage, UK
| | - Danai Dima
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Department of Psychology, School of Arts and Social Sciences, City University of London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Department of Information Engineering, University of Padua, Padua, Italy
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16
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Martins D, Veronese M, Turkheimer FE, Howard MA, Williams SCR, Dipasquale O. A candidate neuroimaging biomarker for detection of neurotransmission-related functional alterations and prediction of pharmacological analgesic response in chronic pain. Brain Commun 2021; 4:fcab302. [PMID: 35169702 PMCID: PMC8833258 DOI: 10.1093/braincomms/fcab302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 09/10/2021] [Accepted: 12/21/2021] [Indexed: 01/29/2023] Open
Abstract
Chronic pain is a world-wide clinical challenge. Response to analgesic treatment is limited and difficult to predict. Functional MRI has been suggested as a potential solution. However, while most analgesics target specific neurotransmission pathways, functional MRI-based biomarkers are not specific for any neurotransmitter system, limiting our understanding of how they might contribute to predict treatment response. Here, we sought to bridge this gap by applying Receptor-Enriched Analysis of Functional Connectivity by Targets to investigate whether neurotransmission-enriched functional connectivity mapping can provide insights into the brain mechanisms underlying chronic pain and inter-individual differences in analgesic response after a placebo or duloxetine. We performed secondary analyses of two openly available resting-state functional MRI data sets of 56 patients with chronic knee osteoarthritis pain who underwent pre-treatment brain scans in two clinical trials. Study 1 (n = 17) was a 2-week single-blinded placebo pill trial. Study 2 (n = 39) was a 3-month double-blinded randomized trial comparing placebo to duloxetine, a dual serotonin–noradrenaline reuptake inhibitor. Across two independent studies, we found that patients with chronic pain present alterations in the functional circuit related to the serotonin transporter, when compared with age-matched healthy controls. Placebo responders in Study 1 presented with higher pre-treatment functional connectivity enriched by the dopamine transporter compared to non-responders. Duloxetine responders presented with higher pre-treatment functional connectivity enriched by the serotonin and noradrenaline transporters when compared with non-responders. Neurotransmission-enriched functional connectivity mapping might hold promise as a new mechanistic-informed biomarker for functional brain alterations and prediction of response to pharmacological analgesia in chronic pain.
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Affiliation(s)
- Daniel Martins
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
| | - Matthew A. Howard
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
| | - Steve C. R. Williams
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, De Crespigny Park, London SE5 8AF, UK
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17
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Frison M, Faccenda D, Abeti R, Rigon M, Strobbe D, England-Rendon BS, Cash D, Barnes K, Sadeghian M, Sajic M, Wells LA, Xia D, Giunti P, Smith K, Mortiboys H, Turkheimer FE, Campanella M. The translocator protein (TSPO) is prodromal to mitophagy loss in neurotoxicity. Mol Psychiatry 2021; 26:2721-2739. [PMID: 33664474 PMCID: PMC8505241 DOI: 10.1038/s41380-021-01050-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 01/13/2021] [Accepted: 02/05/2021] [Indexed: 12/14/2022]
Abstract
Dysfunctional mitochondria characterise Parkinson's Disease (PD). Uncovering etiological molecules, which harm the homeostasis of mitochondria in response to pathological cues, is therefore pivotal to inform early diagnosis and therapy in the condition, especially in its idiopathic forms. This study proposes the 18 kDa Translocator Protein (TSPO) to be one of those. Both in vitro and in vivo data show that neurotoxins, which phenotypically mimic PD, increase TSPO to enhance cellular redox-stress, susceptibility to dopamine-induced cell death, and repression of ubiquitin-dependent mitophagy. TSPO amplifies the extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) signalling, forming positive feedback, which represses the transcription factor EB (TFEB) and the controlled production of lysosomes. Finally, genetic variances in the transcriptome confirm that TSPO is required to alter the autophagy-lysosomal pathway during neurotoxicity.
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Affiliation(s)
- Michele Frison
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Danilo Faccenda
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square London, United Kingdom
| | - Manuel Rigon
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy
| | - Daniela Strobbe
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy
| | - Britannie S England-Rendon
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, King's College London, Camberwell, United Kingdom
| | - Katy Barnes
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Mona Sadeghian
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Marija Sajic
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Lisa A Wells
- Imanova Limited, Centre for Imaging Sciences, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Dong Xia
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square London, United Kingdom
| | - Kenneth Smith
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Heather Mortiboys
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, King's College London, Camberwell, United Kingdom
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom.
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy.
- University College London Consortium for Mitochondrial Research, London, United Kingdom.
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18
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Lukow PB, Kiemes A, Kempton MJ, Turkheimer FE, McGuire P, Modinos G. Neural correlates of emotional processing in psychosis risk and onset - A systematic review and meta-analysis of fMRI studies. Neurosci Biobehav Rev 2021; 128:780-788. [PMID: 33722617 PMCID: PMC8345001 DOI: 10.1016/j.neubiorev.2021.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/17/2020] [Accepted: 03/08/2021] [Indexed: 11/16/2022]
Abstract
The neural bases of altered emotion processing in psychosis are still unclear. Systematic review indicated widespread activation decreases to emotion in first-episode psychosis. Evidence in people at clinical high-risk for psychosis lacked convergence. These findings were corroborated by image-based meta-analyses.
Aberrant emotion processing is a well-established component of psychotic disorders and is already present at the first episode of psychosis (FEP). However, the role of emotion processing abnormalities in the emergence of psychosis and the underlying neurobiology remain unclear. Here, we systematically reviewed functional magnetic resonance studies that used emotion processing task paradigms in FEP patients, and in people at clinical high-risk for psychosis (CHRp). Image-based meta-analyses with Seed-based d Mapping on available studies (n = 6) were also performed. Compared to controls, FEP patients showed decreased neural responses to emotion, particularly in the amygdala and anterior cingulate cortex. There were no significant differences between CHRp subjects and controls, but a high degree of heterogeneity was identified across studies. The role of altered emotion processing in the early phase of psychosis may be clarified through more homogenous experimental designs, particularly in the CHRp population.
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Affiliation(s)
- P B Lukow
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK.
| | - A Kiemes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK.
| | - M J Kempton
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK.
| | - F E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK.
| | - P McGuire
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK.
| | - G Modinos
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK; Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, SE5 8AF, London, UK; MRC Centre for Neurodevelopmental Disorders, King's College London, new hunt's House, Guy's Campus, SE1 1UL, London, UK.
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19
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Selvaggi P, Rizzo G, Mehta MA, Turkheimer FE, Veronese M. Integration of human whole-brain transcriptome and neuroimaging data: Practical considerations of current available methods. J Neurosci Methods 2021; 355:109128. [PMID: 33722642 DOI: 10.1016/j.jneumeth.2021.109128] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/12/2021] [Accepted: 03/01/2021] [Indexed: 12/20/2022]
Abstract
The Allen Human Brain Atlas (AHBA) is the first example of human brain transcriptomic mappings and detailed anatomical annotations which, for the first time, has allowed the integration of human brain transcriptomics with neuroimaging. This has been made possible because the AHBA offered an original dataset that contains mRNA expression measures for >20,000 genes covering the whole brain and, critically, in a standard stereotaxic space. In recent years many different methods have been used to integrate this data set with brain imaging data, although this endeavour has lacked harmony in terms of the workflow of data processing and subsequent analyses. In this work we discuss five main issues that experience has highlighted as in need of thorough consideration when integrating the AHBA with neuroimaging. These concerns are corroborated by comparing the performance of three different publicly available methods in correlating the same measures of serotonin receptors density with the correspondent AHBA mRNA maps. In this representative case, we were able to show how these methods can lead to discrepant results, suggesting that processing options are not neutral. We believe that the field should take into serious consideration these issues as they could undermine reproducibility and, in the end, the intrinsic value of the AHBA. We also advise on possible strategies to overcome these discrepancies. Finally, we encourage authors towards practices that will improve reproducibility such as transparency in reporting, algorithm and data sharing, collaboration.
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Affiliation(s)
- Pierluigi Selvaggi
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Gaia Rizzo
- Invicro, W12 0NN, London, UK; Division of Brain Sciences, Department of Medicine, Imperial College London, SW72AZ, London, UK
| | - Mitul A Mehta
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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20
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Turkheimer FE, Rosas FE, Dipasquale O, Martins D, Fagerholm ED, Expert P, Váša F, Lord LD, Leech R. A Complex Systems Perspective on Neuroimaging Studies of Behavior and Its Disorders. Neuroscientist 2021; 28:382-399. [PMID: 33593120 PMCID: PMC9344570 DOI: 10.1177/1073858421994784] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The study of complex systems deals with emergent behavior that arises as
a result of nonlinear spatiotemporal interactions between a large
number of components both within the system, as well as between the
system and its environment. There is a strong case to be made that
neural systems as well as their emergent behavior and disorders can be
studied within the framework of complexity science. In particular, the
field of neuroimaging has begun to apply both theoretical and
experimental procedures originating in complexity science—usually in
parallel with traditional methodologies. Here, we illustrate the basic
properties that characterize complex systems and evaluate how they
relate to what we have learned about brain structure and function from
neuroimaging experiments. We then argue in favor of adopting a complex
systems-based methodology in the study of neuroimaging, alongside
appropriate experimental paradigms, and with minimal influences from
noncomplex system approaches. Our exposition includes a review of the
fundamental mathematical concepts, combined with practical examples
and a compilation of results from the literature.
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Affiliation(s)
- Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Fernando E Rosas
- Centre for Psychedelic Research, Department of Brain Sciences, Imperial College London, London, UK.,Data Science Institute, Imperial College London, London, UK.,Centre for Complexity Science, Imperial College London, London, UK
| | - Ottavia Dipasquale
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Daniel Martins
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Erik D Fagerholm
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Paul Expert
- Global Digital Health Unit, School of Public Health, Imperial College London, London, UK
| | - František Váša
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | | | - Robert Leech
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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21
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Schubert JJ, Veronese M, Fryer TD, Manavaki R, Kitzbichler MG, Nettis MA, Mondelli V, Pariante CM, Bullmore ET, Turkheimer FE. A Modest Increase in 11C-PK11195-Positron Emission Tomography TSPO Binding in Depression Is Not Associated With Serum C-Reactive Protein or Body Mass Index. Biol Psychiatry Cogn Neurosci Neuroimaging 2021; 6:716-724. [PMID: 33515765 PMCID: PMC8264953 DOI: 10.1016/j.bpsc.2020.12.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 11/27/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023]
Abstract
Background Immune mechanisms have been implicated in the pathogenesis of depression. Translocator protein (TSPO)–targeted positron emission tomography (PET) has been used to assess neuroinflammation in major depressive disorder. We aimed to 1) test the hypothesis of significant case-control differences in TSPO binding in the anterior cingulate cortex, prefrontal cortex, and insula regions; and 2) explore the relationship between cerebral TSPO binding and peripheral blood C-reactive protein (CRP) concentration. Methods A total of 51 depressed subjects with Hamilton Depression Rating Scale score >13 (median 17; interquartile range, 16–22) and 25 healthy control subjects underwent dynamic brain 11C-PK11195 PET and peripheral blood immune marker characterization. Depressed subjects were divided into high CRP (>3 mg/L; n = 20) and low CRP (<3 mg/L; n = 31). Results Across the three regions, TSPO binding was significantly increased in depressed versus control subjects (η2p = .09; F1,71 = 6.97, p = .01), which was not influenced by body mass index. The case-control difference was greatest in the anterior cingulate cortex (d = 0.49; t74 = 2.00, p = .03) and not significant in the prefrontal cortex or insula (d = 0.27 and d = 0.36, respectively). Following CRP stratification, significantly higher TSPO binding was observed in low-CRP depression compared with controls (d = 0.53; t54 = 1.96, p = .03). These effect sizes are comparable to prior major depressive disorder case-control TSPO PET data. No significant correlations were observed between TSPO and CRP measures. Conclusions Consistent with previous findings, there is a modest increase in TSPO binding in depressed patients compared with healthy control subjects. The lack of a significant correlation between brain TSPO binding and blood CRP concentration or body mass index poses questions about the interactions between central and peripheral immune responses in the pathogenesis of depression.
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Affiliation(s)
- Julia J Schubert
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Tim D Fryer
- Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom; Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom
| | - Roido Manavaki
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Manfred G Kitzbichler
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom
| | - Maria A Nettis
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; National Institute for Health and Research Biomedical Research Centre, South London and Maudsley NHS Foundation Trust and King's College London, London, United Kingdom
| | - Valeria Mondelli
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; National Institute for Health and Research Biomedical Research Centre, South London and Maudsley NHS Foundation Trust and King's College London, London, United Kingdom
| | - Carmine M Pariante
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom; National Institute for Health and Research Biomedical Research Centre, South London and Maudsley NHS Foundation Trust and King's College London, London, United Kingdom
| | - Edward T Bullmore
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, United Kingdom
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
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22
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Turkheimer FE, Althubaity N, Schubert J, Nettis MA, Cousins O, Dima D, Mondelli V, Bullmore ET, Pariante C, Veronese M. Increased serum peripheral C-reactive protein is associated with reduced brain barriers permeability of TSPO radioligands in healthy volunteers and depressed patients: implications for inflammation and depression. Brain Behav Immun 2021; 91:487-497. [PMID: 33160089 DOI: 10.1016/j.bbi.2020.10.025] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 10/30/2020] [Accepted: 10/31/2020] [Indexed: 01/08/2023] Open
Abstract
The relationship between peripheral and central immunity and how these ultimately may cause depressed behaviour has been the focus of a number of imaging studies conducted with Positron Emission Tomography (PET). These studies aimed at testing the immune-mediated model of depression that proposes a direct effect of peripheral cytokines and immune cells on the brain to elicit a neuroinflammatory response via a leaky blood-brain barrier and ultimately depressive behaviour. However, studies conducted so far using PET radioligands targeting the neuroinflammatory marker 18 kDa translocator protein (TSPO) in patient cohorts with depression have demonstrated mild inflammatory brain status but no correlation between central and peripheral immunity. To gain a better insight into the relationship between heightened peripheral immunity and neuroinflammation, we estimated blood-to-brain and blood-to-CSF perfusion rates for two TSPO radiotracers collected in two separate studies, one large cross-sectional study of neuroinflammation in normal and depressed cohorts (N = 51 patients and N = 25 controls) and a second study where peripheral inflammation in N = 7 healthy controls was induced via subcutaneous injection of interferon (IFN)-α. In both studies we observed a consistent negative association between peripheral inflammation, measured with c-reactive protein P (CRP), and radiotracer perfusion into and from the brain parenchyma and CSF. Importantly, there was no association of this effect with the marker of BBB leakage S100β, that was unchanged. These results suggest a different model of peripheral-to-central immunity interaction whereas peripheral inflammation may cause a reduction in BBB permeability. This effect, on the long term, is likely to disrupt brain homeostasis and induce depressive behavioural symptoms.
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Affiliation(s)
- Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Noha Althubaity
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Julia Schubert
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Maria A Nettis
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Oliver Cousins
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Danai Dima
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Department of Psychology, School of Arts and Social Sciences, City, University of London, London, UK
| | - Valeria Mondelli
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Edward T Bullmore
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Carmine Pariante
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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23
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Marques TR, Ashok AH, Angelescu I, Borgan F, Myers J, Lingford-Hughes A, Nutt DJ, Veronese M, Turkheimer FE, Howes OD. GABA-A receptor differences in schizophrenia: a positron emission tomography study using [ 11C]Ro154513. Mol Psychiatry 2021; 26:2616-2625. [PMID: 32296127 PMCID: PMC8440185 DOI: 10.1038/s41380-020-0711-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/17/2020] [Accepted: 03/04/2020] [Indexed: 01/28/2023]
Abstract
A loss of GABA signaling is a prevailing hypothesis for the pathogenesis of schizophrenia. Preclinical studies indicate that blockade of the α5 subtype of the GABA receptor (α5-GABAARs) leads to behavioral phenotypes associated with schizophrenia, and postmortem evidence indicates lower hippocampal α5-GABAARs protein and mRNA levels in schizophrenia. However, it is unclear if α5-GABAARs are altered in vivo or related to symptoms. We investigated α5-GABAARs availability in antipsychotic-free schizophrenia patients and antipsychotic-medicated schizophrenia patients using [11C]Ro15-4513 PET imaging in a cross-sectional, case-control study design. Thirty-one schizophrenia patients (n = 10 antipsychotic free) and twenty-nine matched healthy controls underwent a [11C]Ro15-4513 PET scan and MRI. The α5 subtype GABA-A receptor availability was indexed using [11C]Ro15-4513 PET imaging. Dynamic PET data were analyzed using the two-tissue compartment model with an arterial plasma input function and total volume of distribution (VT) as the outcome measure. Symptom severity was assessed using the PANSS scale. There was significantly lower [11C]Ro15-4513 VT in the hippocampus of antipsychotic-free patients, but not in medicated patients (p = 0.64), relative to healthy controls (p < 0.05; effect size = 1.4). There was also a significant positive correlation between [11C]Ro15-4513 VT and total PANSS score in antipsychotic-free patients (r = 0.72; p = 0.044). The results suggest that antipsychotic-free patients with schizophrenia have lower α5-GABAARs levels in the hippocampus, consistent with the hypothesis that GABA hypofunction underlies the pathophysiology of the disorder.
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Affiliation(s)
- Tiago Reis Marques
- Psychiatric Imaging Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, London, UK. .,Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
| | - Abhishekh H. Ashok
- grid.14105.310000000122478951Psychiatric Imaging Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, London, UK ,grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Ilinca Angelescu
- grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Faith Borgan
- grid.14105.310000000122478951Psychiatric Imaging Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, London, UK ,grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Jim Myers
- grid.7445.20000 0001 2113 8111Faculty of Medicine, Imperial College London, London, UK
| | - Anne Lingford-Hughes
- grid.7445.20000 0001 2113 8111Neuropsychopharmacology Unit, Centre for Psychiatry, Division of Brain Sciences, Imperial College London, London, UK
| | - David J. Nutt
- grid.7445.20000 0001 2113 8111Neuropsychopharmacology Unit, Centre for Psychiatry, Division of Brain Sciences, Imperial College London, London, UK
| | - Mattia Veronese
- grid.13097.3c0000 0001 2322 6764Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Federico E. Turkheimer
- grid.13097.3c0000 0001 2322 6764Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Oliver D. Howes
- grid.14105.310000000122478951Psychiatric Imaging Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, London, UK ,grid.13097.3c0000 0001 2322 6764Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
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24
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Egerton A, Dunn JT, Singh N, Yu Z, O'Doherty J, Koychev I, Webb J, Claridge S, Turkheimer FE, Marsden PK, Hammers A, Gee A. Evaluation of [ 13N]ammonia positron emission tomography as a potential method for quantifying glutamine synthetase activity in the human brain. EJNMMI Res 2020; 10:146. [PMID: 33270177 PMCID: PMC7714883 DOI: 10.1186/s13550-020-00731-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 11/21/2020] [Indexed: 11/22/2022] Open
Abstract
PURPOSE The conversion of synaptic glutamate to glutamine in astrocytes by glutamine synthetase (GS) is critical to maintaining healthy brain activity and may be disrupted in several brain disorders. As the GS catalysed conversion of glutamate to glutamine requires ammonia, we evaluated whether [13N]ammonia positron emission tomography (PET) could reliability quantify GS activity in humans. METHODS In this test-retest study, eight healthy volunteers each received two dynamic [13N]ammonia PET scans on the morning and afternoon of the same day. Each [13N]ammonia scan was preceded by a [15O]water PET scan to account for effects of cerebral blood flow (CBF). RESULTS Concentrations of radioactive metabolites in arterial blood were available for both sessions in five of the eight subjects. Our results demonstrated that kinetic modelling was unable to reliably distinguish estimates of the kinetic rate constant k3 (related to GS activity) from K1 (related to [13N]ammonia brain uptake), and indicated a non-negligible back-flux of [13N] to blood (k2). Model selection favoured a reversible one-tissue compartmental model, and [13N]ammonia K1 correlated reliably (r2 = 0.72-0.92) with [15O]water CBF. CONCLUSION The [13N]ammonia PET method was unable to reliably estimate GS activity in the human brain but may provide an alternative index of CBF.
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Affiliation(s)
- Alice Egerton
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London, SE5 8AF, UK.
| | - Joel T Dunn
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
| | - Nisha Singh
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE5 7AF, UK
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, OX3 7JX, UK
| | - Zilin Yu
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
| | - Jim O'Doherty
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
- Clinical Imaging Research Centre, National University of Singapore, Singapore, 117599, Singapore
| | - Ivan Koychev
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, London, SE5 8AF, UK
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, OX3 7JX, UK
| | - Jessica Webb
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
| | - Simon Claridge
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE5 7AF, UK
| | - Paul K Marsden
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
| | - Alexander Hammers
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
| | - Antony Gee
- School of Biomedical Engineering and Imaging Sciences, St Thomas' Hospital, King's College London, London, SE1 7EH, UK
- King's College London & Guy's and St. Thomas' PET Centre, London, SE1 7EH, UK
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25
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Fagerholm ED, Tangwiriyasakul C, Friston KJ, Violante IR, Williams S, Carmichael DW, Perani S, Turkheimer FE, Moran RJ, Leech R, Richardson MP. Neural diffusivity and pre-emptive epileptic seizure intervention. PLoS Comput Biol 2020; 16:e1008448. [PMID: 33259483 PMCID: PMC7732083 DOI: 10.1371/journal.pcbi.1008448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 12/11/2020] [Accepted: 10/15/2020] [Indexed: 11/25/2022] Open
Abstract
The propagation of epileptic seizure activity in the brain is a widespread pathophysiology that, in principle, should yield to intervention techniques guided by mathematical models of neuronal ensemble dynamics. During a seizure, neural activity will deviate from its current dynamical regime to one in which there are significant signal fluctuations. In silico treatments of neural activity are an important tool for the understanding of how the healthy brain can maintain stability, as well as of how pathology can lead to seizures. The hope is that, contained within the mathematical foundations of such treatments, there lie potential strategies for mitigating instabilities, e.g. via external stimulation. Here, we demonstrate that the dynamic causal modelling neuronal state equation generalises to a Fokker-Planck formalism if one extends the framework to model the ways in which activity propagates along the structural connections of neural systems. Using the Jacobian of this generalised state equation, we show that an initially unstable system can be rendered stable via a reduction in diffusivity–i.e., by lowering the rate at which neuronal fluctuations disperse to neighbouring regions. We show, for neural systems prone to epileptic seizures, that such a reduction in diffusivity can be achieved via external stimulation. Specifically, we show that this stimulation should be applied in such a way as to temporarily mirror the activity profile of a pathological region in its functionally connected areas. This counter-intuitive method is intended to be used pre-emptively–i.e., in order to mitigate the effects of the seizure, or ideally even prevent it from occurring in the first place. We offer proof of principle using simulations based on functional neuroimaging data collected from patients with idiopathic generalised epilepsy, in which we successfully suppress pathological activity in a distinct sub-network prior to seizure onset. Our hope is that this technique can form the basis for future real-time monitoring and intervention devices that are capable of treating epilepsy in a non-invasive manner. Epilepsy is a disease that affects over 50 million people worldwide. Current treatments include dangerous surgical procedures in which brain connections are severed, or even in which entire problem brain regions are removed. Pharmaceutical options are available, but only about one third of patients are responsive. However, even in these cases the drugs can cause such severe side effects that the patients sometimes choose to suffer seizures. We are proposing an innovative treatment of epilepsy that could be achieved by using non-invasive electrical stimulation. Specifically, we show that stimulation should be applied in such a way as to mirror the activity in a problem brain region, by targeting its neighbouring areas. This counterintuitive approach is based on a mathematical model in which this mirroring strategy is applied pre-emptively, i.e. long before the seizure has a chance to set in. The hope is that future clinical trials will be able to use this model to lessen the effect of seizures, or even prevent them from occurring in the first place.
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Affiliation(s)
- Erik D. Fagerholm
- Department of Neuroimaging, King’s College London, London, United Kingdom
- * E-mail:
| | - Chayanin Tangwiriyasakul
- Department of Basic and Clinical Neuroscience, King's College London, London, United Kingdom
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London, United Kingdom
| | - Karl J. Friston
- Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom
| | - Inês R. Violante
- School of Psychology, University of Surrey, Guildford, United Kingdom
| | - Steven Williams
- Department of Neuroimaging, King’s College London, London, United Kingdom
| | - David W. Carmichael
- School of Biomedical Engineering & Imaging Sciences, King’s College London, London, United Kingdom
- Developmental Neurosciences, University College London, London, United Kingdom
| | - Suejen Perani
- Department of Basic and Clinical Neuroscience, King's College London, London, United Kingdom
- UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | | | - Rosalyn J. Moran
- Department of Neuroimaging, King’s College London, London, United Kingdom
| | - Robert Leech
- Department of Neuroimaging, King’s College London, London, United Kingdom
| | - Mark P. Richardson
- Department of Basic and Clinical Neuroscience, King's College London, London, United Kingdom
- Centre for Epilepsy, King's College Hospital, London, United Kingdom
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26
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Wright P, Veronese M, Mazibuko N, Turkheimer FE, Rabiner EA, Ballard CG, Williams SCR, Hari Narayanan AK, Osrah B, Williams R, Marques TR, Howes OD, Roncaroli F, O'Sullivan MJ. Patterns of Mitochondrial TSPO Binding in Cerebral Small Vessel Disease: An in vivo PET Study With Neuropathological Comparison. Front Neurol 2020; 11:541377. [PMID: 33178101 PMCID: PMC7596201 DOI: 10.3389/fneur.2020.541377] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 08/20/2020] [Indexed: 12/11/2022] Open
Abstract
Small vessel disease (SVD) is associated with cognitive impairment in older age and be implicated in vascular dementia. Post-mortem studies show proliferation of activated microglia in the affected white matter. However, the role of inflammation in SVD pathogenesis is incompletely understood and better biomarkers are needed. We hypothesized that expression of the 18 kDa translocator protein (TSPO), a marker of microglial activation, would be higher in SVD. Positron emission tomography (PET) was performed with the second-generation TSPO ligand [11C]PBR28 in 11 participants with SVD. TSPO binding was evaluated by a two-tissue compartment model, with and without a vascular binding component, in white matter hyperintensities (WMH) and normal-appearing white matter (NAWM). In post-mortem tissue, in a separate cohort of individuals with SVD, immunohistochemistry was performed for TSPO and a pan-microglial marker Iba1. Kinetic modeling showed reduced tracer volume and blood volume fraction in WMH compared with NAWM, but a significant increase in vascular binding. Vascular [11C]PBR28 binding was also increased compared with normal-appearing white matter of healthy participants free of SVD. Immunohistochemistry showed a diffuse increase in microglial staining (with Iba1) in sampled tissue in SVD compared with control samples, but with only a subset of microglia staining positively for TSPO. Intense TSPO staining was observed in the vicinity of damaged small blood vessels, which included perivascular macrophages. The results suggest an altered phenotype of activated microglia, with reduced TSPO expression, in the areas of greatest white matter ischemia in SVD, with implications for the interpretation of TSPO PET studies in older individuals or those with vascular risk factors.
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Affiliation(s)
- Paul Wright
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Ndabezinhle Mazibuko
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Eugenii A. Rabiner
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
- Invicro, London, United Kingdom
| | - Clive G. Ballard
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Steven C. R. Williams
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Avinash Kumar Hari Narayanan
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Bahiya Osrah
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Ricky Williams
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Tiago R. Marques
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Oliver D. Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Federico Roncaroli
- Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- Manchester Centre for Clinical Neuroscience, Salford Royal Foundation Trust, Salford, United Kingdom
| | - Michael J. O'Sullivan
- Department of Neuroimaging, Institute of Psychiatry Psychology & Neuroscience, King's College London, London, United Kingdom
- University of Queensland Centre for Clinical Research, Brisbane, QLD, Australia
- Department of Neurology, The Royal Brisbane and Women's Hospital, Herston, QLD, Australia
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27
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Turkheimer FE, Fagerholm ED, Vignando M, Dafflon J, Da Costa PF, Dazzan P, Leech R. A GABA Interneuron Deficit Model of the Art of Vincent van Gogh. Front Psychiatry 2020; 11:685. [PMID: 32754073 PMCID: PMC7370815 DOI: 10.3389/fpsyt.2020.00685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 06/30/2020] [Indexed: 11/17/2022] Open
Abstract
Vincent van Gogh was one of the most influential artists of the Western world, having shaped the post-impressionist art movement by shifting its boundaries forward into abstract expressionism. His distinctive style, which was not valued by the art-buying public during his lifetime, is nowadays one of the most sought after. However, despite the great deal of attention from academic and artistic circles, one important question remains open: was van Gogh's original style a visual manifestation distinct from his troubled mind, or was it in fact a by-product of an impairment that resulted from the psychiatric illness that marred his entire life? In this paper, we use a previously published multi-scale model of brain function to piece together a number of disparate observations about van Gogh's life and art. In particular, we first quantitatively analyze the brushwork of his large production of self-portraits using the image autocorrelation and demonstrate a strong association between the contrasts in the paintings, the occurrence of psychiatric symptoms, and his simultaneous use of absinthe-a strong liquor known to affect gamma aminobutyric acid (GABA) alpha receptors. Secondly, we propose that van Gogh suffered from a defective function of parvalbumin interneurons, which seems likely given his family history of schizophrenia and his addiction to substances associated with GABA action. This could explain the need for the artist to increasingly amplify the contrasts in his brushwork as his disease progressed, as well as his tendency to merge esthetic and personal experiences into a new form of abstraction.
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Affiliation(s)
- Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology, and Neuroscience, King’s College London, London, United Kingdom
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McCutcheon RA, Jauhar S, Pepper F, Nour MM, Rogdaki M, Veronese M, Turkheimer FE, Egerton A, McGuire P, Mehta MM, Howes OD. The Topography of Striatal Dopamine and Symptoms in Psychosis: An Integrative Positron Emission Tomography and Magnetic Resonance Imaging Study. Biol Psychiatry Cogn Neurosci Neuroimaging 2020; 5:1040-1051. [PMID: 32653578 PMCID: PMC7645803 DOI: 10.1016/j.bpsc.2020.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/10/2020] [Accepted: 04/10/2020] [Indexed: 02/05/2023]
Abstract
Background Striatal dopamine dysfunction is thought to underlie symptoms in psychosis, yet it remains unclear how a single neurotransmitter could cause the diverse presentations that are observed clinically. One hypothesis is that the consequences of aberrant dopamine signaling vary depending on where within the striatum the dysfunction occurs. Positron emission tomography allows for the quantification of dopamine function across the striatum. In the current study, we used a novel method to investigate the relationship between spatial variability in dopamine synthesis capacity and psychotic symptoms. Methods We used a multimodal imaging approach combining 18F-DOPA positron emission tomography and resting-state magnetic resonance imaging in 29 patients with first-episode psychosis and 21 healthy control subjects. In each participant, resting-state functional connectivity maps were used to quantify the functional connectivity of each striatal voxel to well-established cortical networks. Network-specific striatal dopamine synthesis capacity (Kicer) was then calculated for the resulting connectivity-defined parcellations. Results The connectivity-defined parcellations generated Kicer values with equivalent reliability, and significantly greater orthogonality compared with standard anatomical parcellation methods. As a result, dopamine-symptom associations were significantly different from one another for different subdivisions, whereas no unique subdivision relationships were found when using an anatomical parcellation. In particular, dopamine function within striatal areas connected to the default mode network was strongly associated with negative symptoms (p < .001). Conclusions These findings suggest that individual differences in the topography of dopamine dysfunction within the striatum contribute to shaping psychotic symptomatology. Further validation of the novel approach in future studies is necessary.
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Affiliation(s)
- Robert A McCutcheon
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, Imperial College London, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom.
| | - Sameer Jauhar
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, Imperial College London, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Fiona Pepper
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Matthew M Nour
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom; Wellcome Centre for Human Neuroimaging, University College London, London, United Kingdom
| | - Maria Rogdaki
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, Imperial College London, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Alice Egerton
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Philip McGuire
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Mitul M Mehta
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Oliver D Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, Imperial College London, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
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Turkheimer FE, Selvaggi P, Mehta MA, Veronese M, Zelaya F, Dazzan P, Vernon AC. Normalizing the Abnormal: Do Antipsychotic Drugs Push the Cortex Into an Unsustainable Metabolic Envelope? Schizophr Bull 2020; 46:484-495. [PMID: 31755955 PMCID: PMC7147598 DOI: 10.1093/schbul/sbz119] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The use of antipsychotic medication to manage psychosis, principally in those with a diagnosis of schizophrenia or bipolar disorder, is well established. Antipsychotics are effective in normalizing positive symptoms of psychosis in the short term (delusions, hallucinations and disordered thought). Their long-term use is, however, associated with side effects, including several types of movement (extrapyramidal syndrome, dyskinesia, akathisia), metabolic and cardiac disorders. Furthermore, higher lifetime antipsychotic dose-years may be associated with poorer cognitive performance and blunted affect, although the mechanisms driving the latter associations are not well understood. In this article, we propose a novel model of the long-term effects of antipsychotic administration focusing on the changes in brain metabolic homeostasis induced by the medication. We propose here that the brain metabolic normalization, that occurs in parallel to the normalization of psychotic symptoms following antipsychotic treatment, may not ultimately be sustainable by the cerebral tissue of some patients; these patients may be characterized by already reduced oxidative metabolic capacity and this may push the brain into an unsustainable metabolic envelope resulting in tissue remodeling. To support this perspective, we will review the existing data on the brain metabolic trajectories of patients with a diagnosis of schizophrenia as indexed using available neuroimaging tools before and after use of medication. We will also consider data from pre-clinical studies to provide mechanistic support for our model.
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Affiliation(s)
- Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King’s College London, London, UK
| | - Pierluigi Selvaggi
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Mitul A Mehta
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Fernando Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Paola Dazzan
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Anthony C Vernon
- MRC Centre for Neurodevelopmental Disorders, King’s College London, London, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
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Kim S, Jung WH, Howes OD, Veronese M, Turkheimer FE, Lee YS, Lee JS, Kim E, Kwon JS. Frontostriatal functional connectivity and striatal dopamine synthesis capacity in schizophrenia in terms of antipsychotic responsiveness: an [ 18F]DOPA PET and fMRI study. Psychol Med 2019; 49:2533-2542. [PMID: 30460891 DOI: 10.1017/s0033291718003471] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Given that only a subgroup of patients with schizophrenia responds to first-line antipsychotic drugs, a key clinical question is what underlies treatment response. Observations that prefrontal activity correlates with striatal dopaminergic function, have led to the hypothesis that disrupted frontostriatal functional connectivity (FC) could be associated with altered dopaminergic function. Thus, the aim of this study was to investigate the relationship between frontostriatal FC and striatal dopamine synthesis capacity in patients with schizophrenia who had responded to first-line antipsychotic drug compared with those who had failed but responded to clozapine. METHODS Twenty-four symptomatically stable patients with schizophrenia were recruited from Seoul National University Hospital, 12 of which responded to first-line antipsychotic drugs (first-line AP group) and 12 under clozapine (clozapine group), along with 12 matched healthy controls. All participants underwent resting-state functional magnetic resonance imaging and [18F]DOPA PET scans. RESULTS No significant difference was found in the total PANSS score between the patient groups. Voxel-based analysis showed a significant correlation between frontal FC to the associative striatum and the influx rate constant of [18F]DOPA in the corresponding region in the first-line AP group. Region-of-interest analysis confirmed the result (control group: R2 = 0.019, p = 0.665; first-line AP group: R2 = 0.675, p < 0.001; clozapine group: R2 = 0.324, p = 0.054) and the correlation coefficients were significantly different between the groups. CONCLUSIONS The relationship between striatal dopamine synthesis capacity and frontostriatal FC is different between responders to first-line treatment and clozapine treatment in schizophrenia, indicating that a different pathophysiology could underlie schizophrenia in patients who respond to first-line treatments relative to those who do not.
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Affiliation(s)
- Seoyoung Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
| | - Wi Hoon Jung
- Department of Psychology, College of Liberal Arts, Korea University, Seoul, Republic of Korea
| | - Oliver D Howes
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Psychiatric Imaging, Medical Research Council Clinical Sciences Centre, Imperial College London, Hammersmith Hospital Campus, London, UK
| | - Mattia Veronese
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Federico E Turkheimer
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Yun-Sang Lee
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea
| | - Jae Sung Lee
- Department of Nuclear Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea
- Department of Brain & Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - Euitae Kim
- Department of Neuropsychiatry, Seoul National University Bundang Hospital, Gyeonggi-do, Republic of Korea
- Department of Psychiatry, College of Medicine, Seoul National University, Seoul, Republic of Korea
| | - Jun Soo Kwon
- Department of Brain & Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
- Department of Psychiatry, College of Medicine, Seoul National University, Seoul, Republic of Korea
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Marques TR, Ashok AH, Pillinger T, Veronese M, Turkheimer FE, Dazzan P, Sommer IE, Howes OD. Neuroinflammation in schizophrenia: meta-analysis of in vivo microglial imaging studies. Psychol Med 2019; 49:2186-2196. [PMID: 30355368 PMCID: PMC6366560 DOI: 10.1017/s0033291718003057] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/24/2018] [Accepted: 09/25/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Converging lines of evidence implicate an important role for the immune system in schizophrenia. Microglia are the resident immune cells of the central nervous system and have many functions including neuroinflammation, axonal guidance and neurotrophic support. We aimed to provide a quantitative review of in vivo PET imaging studies of microglia activation in patients with schizophrenia compared with healthy controls. METHODS Demographic, clinical and imaging measures were extracted from each study and meta-analysis was conducted using a random-effects model (Hedge's g). The difference in 18-kDa translocator protein (TSPO) binding between patients with schizophrenia and healthy controls, as quantified by either binding potential (BP) or volume of distribution (VT), was used as the main outcome. Sub-analysis and sensitivity analysis were carried out to investigate the effects of genotype, ligand and illness stage. RESULTS In total, 12 studies comprising 190 patients with schizophrenia and 200 healthy controls met inclusion criteria. There was a significant elevation in tracer binding in schizophrenia patients relative to controls when BP was used as an outcome measure, (Hedge's g = 0.31; p = 0.03) but no significant differences when VT was used (Hedge's g = -0.22; p = 0.29). CONCLUSIONS In conclusion, there is evidence for moderate elevations in TSPO tracer binding in grey matter relative to other brain tissue in schizophrenia when using BP as an outcome measure, but no difference when VT is the outcome measure. We discuss the relevance of these findings as well as the methodological issues that may underlie the contrasting difference between these outcomes.
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Affiliation(s)
- Tiago Reis Marques
- Psychiatric Imaging Group, MRC Clinical Sciences Centre, Du Cane Road, London W12 0NN, UK
- Psychiatric Imaging Group, London Institute of Medical Sciences (LMS), Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Abhishekh H Ashok
- Psychiatric Imaging Group, MRC Clinical Sciences Centre, Du Cane Road, London W12 0NN, UK
- Psychiatric Imaging Group, London Institute of Medical Sciences (LMS), Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
| | - Toby Pillinger
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
| | - Federico E. Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
| | - Paola Dazzan
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
| | - Iris E.C. Sommer
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Oliver D Howes
- Psychiatric Imaging Group, MRC Clinical Sciences Centre, Du Cane Road, London W12 0NN, UK
- Psychiatric Imaging Group, London Institute of Medical Sciences (LMS), Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
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Rizzo G, Veronese M, Tonietto M, Bodini B, Stankoff B, Wimberley C, Lavisse S, Bottlaender M, Bloomfield PS, Howes O, Zanotti-Fregonara P, Turkheimer FE, Bertoldo A. Generalization of endothelial modelling of TSPO PET imaging: Considerations on tracer affinities. J Cereb Blood Flow Metab 2019; 39:874-885. [PMID: 29135382 PMCID: PMC6501510 DOI: 10.1177/0271678x17742004] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The 18 kDa translocator protein (TSPO) is a marker of microglia activation and the main target of positron emission tomography (PET) ligands for neuroinflammation. Previous works showed that accounting for TSPO endothelial binding improves PET quantification for [11C]PBR28, [18F]DPA714 and [11C]-R-PK11195. It is still unclear, however, whether the vascular signal is tracer-dependent. This work aims to explore the relationship between the TSPO vascular and tissue components for PET tracers with varying affinity, also assessing the impact of affinity towards the differentiability amongst kinetics and the ensuing ligand amenability to cluster analysis for the extraction of a reference region. First, we applied the compartmental model accounting for vascular binding to [11C]-R-PK11195 data from six healthy subjects. Then, we compared the [11C]-R-PK11195 vascular binding estimates with previously published values for [18F]DPA714 and [11C]PBR28. Finally, we determined the suitability for reference region extraction by calculating the angle between grey and white matter kinetics. Our results showed that endothelial binding is common to all TSPO tracers and proportional to their affinity. By consequence, grey and white matter kinetics were most similar for the radioligand with the highest affinity (i.e. [11C]PBR28), hence poorly suited for the extraction of a reference region using supervised clustering.
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Affiliation(s)
- Gaia Rizzo
- 1 Department of Information Engineering, Padova University, Padova, Italy
| | - Mattia Veronese
- 2 Department of Neuroimaging, King's College London, London, UK
| | - Matteo Tonietto
- 3 UPMC, Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, Paris, France
| | - Benedetta Bodini
- 3 UPMC, Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, Paris, France.,4 Assistance Publique des Hopitaux de Paris, APHP, Hôpital Saint Antoine, Paris, France
| | - Bruno Stankoff
- 3 UPMC, Institut du Cerveau et de la Moelle épinière, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, Paris, France.,4 Assistance Publique des Hopitaux de Paris, APHP, Hôpital Saint Antoine, Paris, France.,5 IMIV, Inserm, CEA, Paris-Sud Univ, Université Paris Saclay, Orsay, France
| | - Catriona Wimberley
- 5 IMIV, Inserm, CEA, Paris-Sud Univ, Université Paris Saclay, Orsay, France
| | - Sonia Lavisse
- 6 Département de Recherche Fondamentale (DRF), Institut d'Imagerie Biomédicale (I2BM), Fontenay-aux-Roses, France.,7 Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud, Université Paris-Saclay, Fontenay-aux-Roses, France
| | - Michel Bottlaender
- 5 IMIV, Inserm, CEA, Paris-Sud Univ, Université Paris Saclay, Orsay, France.,8 Neurospin, CEA, Gif-sur-Yvette, France
| | | | - Oliver Howes
- 9 Institute of Clinical Sciences, Imperial College London, London, UK.,10 Department of Psychosis Studies, King's College London, London, UK
| | - Paolo Zanotti-Fregonara
- 11 Houston Methodist Hospital, PET Core Facility, Research Institute, Stanley H. Appel Department of Neurology, Houston, Texas, USA
| | | | - Alessandra Bertoldo
- 1 Department of Information Engineering, Padova University, Padova, Italy.,12 Padua Neuroscience Center, University of Padova, Padova, Italy
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Schubert JJ, Veronese M, Marchitelli L, Bodini B, Tonietto M, Stankoff B, Brooks DJ, Bertoldo A, Edison P, Turkheimer FE. Dynamic 11C-PiB PET Shows Cerebrospinal Fluid Flow Alterations in Alzheimer Disease and Multiple Sclerosis. J Nucl Med 2019; 60:1452-1460. [PMID: 30850505 DOI: 10.2967/jnumed.118.223834] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/20/2019] [Indexed: 01/26/2023] Open
Abstract
Cerebrospinal fluid (CSF) plays an important role in solute clearance and maintenance of brain homeostasis. 11C-Pittsburgh compound B (PiB) PET was recently proposed as a tool for detection of CSF clearance alterations in Alzheimer disease. The current study investigates the magnitude of 11C-PiB PET signal in the lateral ventricles of an independent group of Alzheimer and mild cognitive impairment subjects. We have also evaluated multiple sclerosis as a model of disease with CSF clearance alterations without amyloid-β tissue accumulation. Methods: A set of 11 Alzheimer and 12 mild cognitive impairment subjects and a set of 20 multiple sclerosis subjects with matched controls underwent MRI and dynamic 11C-PiB PET. Lateral ventricle regions of interest were generated manually from MRI data. PET data were analyzed using cerebellum or a supervised reference region for the Alzheimer and multiple sclerosis data sets, respectively. The magnitude of 11C-PiB signal in the lateral ventricles was calculated as area under the curve from 35 to 80 min and SUV ratio (SUVR) from 50 to 70 min. Compartmental modeling analysis was performed on a separate data set containing 11 Alzheimer and matched control subjects; this analysis included an arterial input function, to further understand the kinetics of the lateral ventricular 11C-PiB signal. Results: ANOVA revealed significant group differences in lateral ventricular SUVR across the Alzheimer, mild cognitive impairment, and healthy control groups (P = 0.004). Pairwise comparisons revealed significantly lower lateral ventricular SUVR in Alzheimer subjects than in healthy controls (P < 0.001) or mild cognitive impairment subjects (P = 0.029). Lateral ventricular SUVR was significantly lower in multiple sclerosis subjects than in healthy controls (P = 0.008). Compartmental modeling analysis revealed significantly lower uptake rates of 11C-PiB signal from blood (P = 0.005) and brain tissue (P = 0.004) to the lateral ventricles and significantly lower 11C-PiB signal clearance out of the lateral ventricles (P = 0.002) in Alzheimer subjects than in healthy controls. Conclusion: These results indicate that dynamic 11C-PiB PET can be used to observe pathologic changes in CSF dynamics. We have replicated previous work demonstrating CSF clearance deficits in Alzheimer disease associated with amyloid-β deposits and have extended the observations to include ventricular CSF clearance deficits in mild cognitive impairment and multiple sclerosis.
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Affiliation(s)
- Julia J Schubert
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Livia Marchitelli
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Benedetta Bodini
- Sorbonne Universités, UPMC Paris 06, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Matteo Tonietto
- Sorbonne Universités, UPMC Paris 06, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Bruno Stankoff
- Sorbonne Universités, UPMC Paris 06, Institut du Cerveau et de la Moelle épinière, ICM, Hôpital de la Pitié Salpêtrière, Paris, France
| | | | | | - Paul Edison
- Imperial College London, London, United Kingdom; and
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
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Veronese M, Moro L, Arcolin M, Dipasquale O, Rizzo G, Expert P, Khan W, Fisher PM, Svarer C, Bertoldo A, Howes O, Turkheimer FE. Covariance statistics and network analysis of brain PET imaging studies. Sci Rep 2019; 9:2496. [PMID: 30792460 PMCID: PMC6385265 DOI: 10.1038/s41598-019-39005-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 01/09/2019] [Indexed: 02/06/2023] Open
Abstract
The analysis of structural and functional neuroimaging data using graph theory has increasingly become a popular approach for visualising and understanding anatomical and functional relationships between different cerebral areas. In this work we applied a network-based approach for brain PET studies using population-based covariance matrices, with the aim to explore topological tracer kinetic differences in cross-sectional investigations. Simulations, test-retest studies and applications to cross-sectional datasets from three different tracers ([18F]FDG, [18F]FDOPA and [11C]SB217045) and more than 400 PET scans were investigated to assess the applicability of the methodology in healthy controls and patients. A validation of statistics, including the assessment of false positive differences in parametric versus permutation testing, was also performed. Results showed good reproducibility and general applicability of the method within the range of experimental settings typical of PET neuroimaging studies, with permutation being the method of choice for the statistical analysis. The use of graph theory for the quantification of [18F]FDG brain PET covariance, including the definition of an entropy metric, proved to be particularly relevant for Alzheimer's disease, showing an association with the progression of the pathology. This study shows that covariance statistics can be applied to PET neuroimaging data to investigate the topological characteristics of the tracer kinetics and its related targets, although sensitivity to experimental variables, group inhomogeneities and image resolution need to be considered when the method is applied to cross-sectional studies.
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Affiliation(s)
- Mattia Veronese
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom.
| | - Lucia Moro
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Marco Arcolin
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Ottavia Dipasquale
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom
| | | | - Paul Expert
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom
- Department of Mathematics, Imperial College London, London, United Kingdom
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College London, London, United Kingdom
| | - Wasim Khan
- Department of Neuroimaging, IoPPN, King's College London, London, United Kingdom
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, Melbourne, Australia
| | - Patrick M Fisher
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Claus Svarer
- Neurobiology Research Unit, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | | | - Oliver Howes
- Department of Psychosis studies, IoPPN, King's College London, London, United Kingdom
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35
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Kübler D, Wächter T, Cabanel N, Su Z, Turkheimer FE, Dodel R, Brooks DJ, Oertel WH, Gerhard A. Widespread microglial activation in multiple system atrophy. Mov Disord 2019; 34:564-568. [PMID: 30726574 PMCID: PMC6659386 DOI: 10.1002/mds.27620] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 12/31/2018] [Accepted: 01/02/2019] [Indexed: 11/22/2022] Open
Abstract
Background The pattern and role of microglial activation in multiple system atrophy is largely unclear. The objective of this study was to use [11C](R)‐PK11195 PET to determine the extent and correlation of activated microglia with clinical parameters in MSA patients. Methods Fourteen patients with the parkinsonian phenotype of MSA (MSA‐P) with a mean disease duration of 2.9 years (range 2‐5 years) were examined with [11C](R)‐PK11195 PET and compared with 10 healthy controls. Results Patients with the parkinsonian phenotype of MSA showed a significant (P ≤ 0.01) mean increase in binding potentials compared with healthy controls in the caudate nucleus, putamen, pallidum, precentral gyrus, orbitofrontal cortex, presubgenual anterior cingulate cortex, and the superior parietal gyrus. No correlations between binding potentials and clinical parameters were found. Conclusions In early clinical stages of the parkinsonian phenotype of MSA, there is widespread microglial activation as a marker of neuroinflammatory changes without correlation to clinical parameters in our patient population. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Dorothee Kübler
- Movement Disorders Section, Department of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Tobias Wächter
- Hertie-Institute for Clinical Brain Research, Department of Neurodegenerative Diseases, Tübingen, Germany.,Department of Neurology, Rehabilitation Centre Bad Gögging, Passauer Wolf, Bad Gögging, Germany
| | - Nicole Cabanel
- Vitos Clinical Centre for Psychiatry and Psychotherapy, Giessen-Marburg, Germany
| | - Zhangjie Su
- Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Richard Dodel
- Chair of Geriatrics, University Hospital Essen, Center for Geriatric Medicine Haus Berge, Essen, Germany
| | - David J Brooks
- Department of Nuclear Medicine and PET-Centre, Institute of Clinical Medicine, Aarhus University, Aarhus C, Denmark.,Institute of Neuroscience, Newcastle University, Newcastle Upon Tyne, UK
| | - Wolfgang H Oertel
- Department of Neurology, Philipps-Universität Marburg, Marburg, Germany.,Institute for Neurogenomics, Helmholtz Center for Health and Environment, München, Germany
| | - Alexander Gerhard
- Departments of Nulcear Medicine and Geriatric Medicine, University Hospital Essen, Germany.,Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK
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Turkheimer FE, Hellyer P, Kehagia AA, Expert P, Lord LD, Vohryzek J, De Faria Dafflon J, Brammer M, Leech R. Conflicting emergences. Weak vs. strong emergence for the modelling of brain function. Neurosci Biobehav Rev 2019; 99:3-10. [PMID: 30684520 DOI: 10.1016/j.neubiorev.2019.01.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 01/11/2019] [Accepted: 01/19/2019] [Indexed: 02/03/2023]
Abstract
The concept of "emergence" has become commonplace in the modelling of complex systems, both natural and man-made; a functional property" emerges" from a system when it cannot be readily explained by the properties of the system's sub-units. A bewildering array of adaptive and sophisticated behaviours can be observed from large ensembles of elementary agents such as ant colonies, bird flocks or by the interactions of elementary material units such as molecules or weather elements. Ultimately, emergence has been adopted as the ontological support of a number of attempts to model brain function. This manuscript aims to clarify the ontology of emergence and delve into its many facets, particularly into its "strong" and "weak" versions that underpin two different approaches to the modelling of behaviour. The first group of models is here represented by the "free energy" principle of brain function and the "integrated information theory" of consciousness. The second group is instead represented by computational models such as oscillatory networks that use mathematical scalable representations to generate emergent behaviours and are then able to bridge neurobiology with higher mental functions. Drawing on the epistemological literature, we observe that due to their loose mechanistic links with the underlying biology, models based on strong forms of emergence are at risk of metaphysical implausibility. This, in practical terms, translates into the over determination that occurs when the proposed model becomes only one of a large set of possible explanations for the observable phenomena. On the other hand, computational models that start from biologically plausible elementary units, hence are weakly emergent, are not limited by ontological faults and, if scalable and able to realistically simulate the hierarchies of brain output, represent a powerful vehicle for future neuroscientific research programmes.
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Affiliation(s)
| | | | | | - Paul Expert
- EPSRC Centre for Mathematics of Precision Healthcare, Imperial College London, UK
| | | | | | | | - Mick Brammer
- Institute of Psychiatry, King's College London, UK
| | - Robert Leech
- Institute of Psychiatry, King's College London, UK
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Jauhar S, Veronese M, Nour MM, Rogdaki M, Hathway P, Turkheimer FE, Stone J, Egerton A, McGuire P, Kapur S, Howes OD. Determinants of treatment response in first-episode psychosis: an 18F-DOPA PET study. Mol Psychiatry 2019; 24:1502-1512. [PMID: 29679071 PMCID: PMC6331038 DOI: 10.1038/s41380-018-0042-4] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/04/2017] [Accepted: 01/15/2018] [Indexed: 11/10/2022]
Abstract
Psychotic illnesses show variable responses to treatment. Determining the neurobiology underlying this is important for precision medicine and the development of better treatments. It has been proposed that dopaminergic differences underlie variation in response, with striatal dopamine synthesis capacity (DSC) elevated in responders and unaltered in non-responders. We therefore aimed to test this in a prospective cohort, with a nested case-control comparison. 40 volunteers (26 patients with first-episode psychosis and 14 controls) received an 18F-DOPA Positron Emission Tomography scan to measure DSC (Kicer) prior to antipsychotic treatment. Clinical assessments (Positive and Negative Syndrome Scale, PANSS, and Global Assessment of Functioning, GAF) occurred at baseline and following antipsychotic treatment for a minimum of 4 weeks. Response was defined using improvement in PANSS Total score of >50%. Patients were followed up for at least 6 months, and remission criteria applied. There was a significant effect of group on Kicer in associative striatum (F(2, 37) = 7.9, p = 0.001). Kicer was significantly higher in responders compared with non-responders (Cohen's d = 1.55, p = 0.01) and controls (Cohen's d = 1.31, p = 0.02). Kicer showed significant positive correlations with improvements in PANSS-positive (r = 0.64, p < 0.01), PANSS negative (rho = 0.51, p = 0.01), and PANSS total (rho = 0.63, p < 0.01) ratings and a negative relationship with change in GAF (r = -0.55, p < 0.01). Clinical response is related to baseline striatal dopaminergic function. Differences in dopaminergic function between responders and non-responders are present at first episode of psychosis, consistent with dopaminergic and non-dopaminergic sub-types in psychosis, and potentially indicating a neurochemical basis to stratify psychosis.
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Affiliation(s)
- Sameer Jauhar
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK ,0000 0000 9439 0839grid.37640.36Early Intervention Psychosis Clinical Academic Group, South London & Maudsley NHS Trust, London, UK
| | - Mattia Veronese
- 0000 0001 2322 6764grid.13097.3cCentre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK
| | - Matthew M Nour
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK ,0000 0001 0705 4923grid.413629.bPsychiatric Imaging Group MRC London Institute of Medical Sciences, Hammersmith Hospital, London, W12 0NN UK ,0000 0001 0705 4923grid.413629.bInstitute of Clinical Sciences, Faculty of Medicine, Imperial College, Hammersmith Hospital, London, W12 0NN UK
| | - Maria Rogdaki
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK ,0000 0001 0705 4923grid.413629.bPsychiatric Imaging Group MRC London Institute of Medical Sciences, Hammersmith Hospital, London, W12 0NN UK
| | - Pamela Hathway
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK
| | - Federico E. Turkheimer
- 0000 0001 2322 6764grid.13097.3cCentre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK
| | - James Stone
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK ,0000 0001 2322 6764grid.13097.3cCentre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK
| | - Alice Egerton
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK
| | - Philip McGuire
- 0000 0001 2322 6764grid.13097.3cDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King’s College, London, UK ,0000 0000 9439 0839grid.37640.36Early Intervention Psychosis Clinical Academic Group, South London & Maudsley NHS Trust, London, UK
| | - Shitij Kapur
- 0000 0001 2322 6764grid.13097.3cFiona Pepper, Centre for Neuroimaging Sciences, King’s College, London, UK
| | - Oliver D Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College, London, UK. .,Psychiatric Imaging Group MRC London Institute of Medical Sciences, Hammersmith Hospital, London, W12 0NN, UK. .,Institute of Clinical Sciences, Faculty of Medicine, Imperial College, Hammersmith Hospital, London, W12 0NN, UK.
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Singh N, Veronese M, O'Doherty J, Sementa T, Bongarzone S, Cash D, Simmons C, Arcolin M, Marsden PK, Gee A, Turkheimer FE. Assessing the feasibility of intranasal radiotracer administration for in brain PET imaging. Nucl Med Biol 2018; 66:32-39. [PMID: 30208358 PMCID: PMC6288068 DOI: 10.1016/j.nucmedbio.2018.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/18/2018] [Accepted: 08/23/2018] [Indexed: 01/17/2023]
Abstract
Introduction The development of clinically useful tracers for PET imaging is enormously challenging and expensive. The intranasal (IN) route of administration is purported to be a viable route for delivering drugs to the brain but has, as yet, not been investigated for the delivery of PET tracers. If the intranasal (IN) pathway presents a viable option, it extends the PET imaging field by increasing the number of tracers available for human use. Here we report the results of a rodent study testing the feasibility of the IN route to administer radiotracers for brain PET imaging. Methods We used two different, well characterised, brain penetrant radiotracers, [18F]fluorodeoxyglucose ([18F]FDG) and [18F]fallypride, and aimed to evaluate the pharmacokinetics after administration of the tracers via the intranasal route, and contrast this to intravenous administration. Image acquisition was carried out after tracer administration and arterial blood samples were collected at different time intervals, centrifuged to extract plasma and gamma counted. We hypothesised that [brain region]:[plasma] ratios would be higher via the intranasal route as there are two inputs, one directly from the nose to the brain, and another from the peripheral circulation. To assess the feasibility of using this approach clinically, we used these data to estimate radiation dosimetry in humans. Results Contrary to our hypothesis, in case of both radiotracers, we did not see a higher ratio in the expected brain regions, except in the olfactory bulb, that is closest to the nose. It appears that the radiotracers move into the olfactory bulb region, but then do not progress further into other brain regions. Moreover, as the nasal cavity has a small surface area, the extrapolated dosimetry estimations for intranasal human imaging showed an unacceptably high level (15 mSv/MBq) of cumulative skin radiation exposure. Conclusions Therefore, although an attractive route for brain permeation, we conclude that the intranasal route would present difficulties due to non-specific signal and radiation dosimetry considerations for brain PET imaging.
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Affiliation(s)
- Nisha Singh
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom; School Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College London, London SE1 7EH, United Kingdom.
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom
| | - Jim O'Doherty
- PET Imaging Centre Facility, King's College London & Guy's and St Thomas NHS Foundation Trust, St Thomas' Hospital, London SE1 7EH, United Kingdom; Department of Molecular Imaging, Sidra Medicine, Doha, Qatar
| | - Teresa Sementa
- School Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College London, London SE1 7EH, United Kingdom
| | - Salvatore Bongarzone
- School Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College London, London SE1 7EH, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom
| | - Camilla Simmons
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom
| | - Marco Arcolin
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom
| | - Paul K Marsden
- School Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College London, London SE1 7EH, United Kingdom; PET Imaging Centre Facility, King's College London & Guy's and St Thomas NHS Foundation Trust, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Antony Gee
- School Biomedical Engineering & Imaging Sciences, 4th floor Lambeth Wing, St Thomas' Hospital, King's College London, London SE1 7EH, United Kingdom; PET Imaging Centre Facility, King's College London & Guy's and St Thomas NHS Foundation Trust, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, De Crespigny Park, London SE 5 8AF, United Kingdom
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Veronese M, Reis Marques T, Bloomfield PS, Rizzo G, Singh N, Jones D, Agushi E, Mosses D, Bertoldo A, Howes O, Roncaroli F, Turkheimer FE. Kinetic modelling of [ 11C]PBR28 for 18 kDa translocator protein PET data: A validation study of vascular modelling in the brain using XBD173 and tissue analysis. J Cereb Blood Flow Metab 2018; 38:1227-1242. [PMID: 28580888 PMCID: PMC6434448 DOI: 10.1177/0271678x17712388] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The 18 kDa translocator protein (TSPO) is a marker of microglia activation in the central nervous system and represents the main target of radiotracers for the in vivo quantification of neuroinflammation with positron emission tomography (PET). TSPO PET is methodologically challenging given the heterogeneous distribution of TSPO in blood and brain. Our previous studies with the TSPO tracers [11C]PBR28 and [11C]PK11195 demonstrated that a model accounting for TSPO binding to the endothelium improves the quantification of PET data. Here, we performed a validation of the kinetic model with the additional endothelial compartment through a displacement study. Seven subjects with schizophrenia, all high-affinity binders, underwent two [11C]PBR28 PET scans before and after oral administration of 90 mg of the TSPO ligand XBD173. The addition of the endothelial component provided a signal compartmentalization much more consistent with the underlying biology, as only in this model, the blocking study produced the expected reduction in the tracer concentration of the specific tissue compartment, whereas the non-displaceable compartment remained unchanged. In addition, we also studied TSPO expression in vessels using 3D reconstructions of histological data of frontal lobe and cerebellum, demonstrating that TSPO positive vessels account for 30% of the vascular volume in cortical and white matter.
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Affiliation(s)
- Mattia Veronese
- Department of Neuroimaging, IoPPN,
King’s College London, London, UK
| | - Tiago Reis Marques
- Department of Psychosis Studies, IoPPN,
King’s College London, London, UK
- Institute of Clinical Sciences, Imperial
College London, London, UK
| | | | - Gaia Rizzo
- Department of Information Engineering,
Padova University, Padova, Italy
| | - Nisha Singh
- Department of Neuroimaging, IoPPN,
King’s College London, London, UK
| | - Deborah Jones
- Department of Cellular Pathology,
Salford Royal Foundation Trust, Salford, UK
| | - Erjon Agushi
- Division of Neuroscience and
Experimental Psychology, University of Manchester, UK
| | - Dominic Mosses
- Division of Neuroscience and
Experimental Psychology, University of Manchester, UK
| | - Alessandra Bertoldo
- Department of Information Engineering,
Padova University, Padova, Italy
- Padua Neuroscience Center, University of
Padova, Padova, Italy
| | - Oliver Howes
- Department of Psychosis Studies, IoPPN,
King’s College London, London, UK
- Institute of Clinical Sciences, Imperial
College London, London, UK
| | - Federico Roncaroli
- Division of Neuroscience and
Experimental Psychology, University of Manchester, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, IoPPN,
King’s College London, London, UK
- Federico E Turkheimer, Centre for
Neuroimaging Sciences, IoPPN, King’s College London, P089, De Crespigny Park,
Denmark Hill, London SE5 8AF, UK.
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Wilson H, Giordano B, Turkheimer FE, Chaudhuri KR, Politis M. Serotonergic dysregulation is linked to sleep problems in Parkinson's disease. Neuroimage Clin 2018; 18:630-637. [PMID: 29845011 PMCID: PMC5964830 DOI: 10.1016/j.nicl.2018.03.001] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 02/22/2018] [Accepted: 03/01/2018] [Indexed: 02/03/2023]
Abstract
Introduction Sleep disturbances are common non-motor symptoms in Parkinson's disease (PD). Experimental studies suggest involvement of the serotonergic system in the regulation of sleep and arousal. Using [11C]DASB positron emission tomography, a marker of serotonin transporter availability, we investigated whether sleep dysfunction is associated with serotonergic dysfunction in PD. Methods We studied 14 PD patients with sleep dysfunction, 14 PD without sleep dysfunction, and 12 healthy controls. Groups were matched for age, disease duration, severity of motor symptoms, daily intake of levodopa equivalent units, body-mass-index, depression and fatigue. [11C]DASB non-displaceable binding potential (BPND) was calculated for regions with a role in the regulation of sleep and arousal. Results [11C]DASB BPND was reduced by 32–49% in PD patients with sleep dysfunction, and 14–25% in PD without sleep dysfunction, compared to healthy controls. PD patients with sleep dysfunction had lower [11C]DASB BPND in caudate (P < 0.01), putamen (P < 0.001), ventral striatum (P < 0.001), thalamus (P < 0.05), hypothalamus (P < 0.001) and raphe nuclei (P < 0.01), compared to PD without sleep dysfunction. Higher severity of sleep symptoms (assessed with Parkinson Disease Sleep Scale) correlated with lower [11C]DASB binding in caudate (r = 0.77; P < 0.001), putamen (r = 0.84; P < 0.001), ventral striatum (r = 0.86; P < 0.001), thalamus (r = 0.79; P < 0.001), hypothalamus (r = 0.90; P < 0.001) and raphe nuclei (r = 0.83; P < 0.001). Conclusions Our findings demonstrate that sleep dysfunction in PD is associated with reduced serotonergic function in the midbrain raphe, basal ganglia and hypothalamus. Strategies to increase serotonin levels in the brain could be a promising approach to treat sleep dysfunction in PD, and may also have relevance in other neurodegenerative disorders. Reduced PET [11C]DASB binding in Parkinson patients with sleep disturbances PD with sleep disturbances shows loss of serotonin in the striatum, raphe and hypothalamus. Loss of serotonin correlated with severity of sleep symptoms in PD patients. Serotonergic dysfunction could contribute to pathophysiology of sleep disturbances.
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Affiliation(s)
- Heather Wilson
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK
| | - Beniamino Giordano
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK
| | - Federico E Turkheimer
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK; Department of Neuroimaging, Institute of Psychiatry, King's College London, London, UK
| | - Kallol Ray Chaudhuri
- Parkinson's Centre of Excellence, Department of Neurology, King's College Hospital Foundation Trust, UK
| | - Marios Politis
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, London, UK.
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Grecchi E, Veronese M, Bodini B, García-Lorenzo D, Battaglini M, Stankoff B, Turkheimer FE. Multimodal partial volume correction: Application to [ 11C]PIB PET/MRI myelin imaging in multiple sclerosis. J Cereb Blood Flow Metab 2017; 37:3803-3817. [PMID: 28569617 PMCID: PMC5718330 DOI: 10.1177/0271678x17712183] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The [11C]PIB PET tracer, originally developed for amyloid imaging, has been recently repurposed to quantify demyelination and remyelination in multiple sclerosis (MS). Myelin PET imaging, however, is limited by its low resolution that deteriorates the quantification accuracy of white matter (WM) lesions. Here, we introduce a novel partial volume correction (PVC) method called Multiresolution-Multimodal Resolution-Recovery (MM-RR), which uses the wavelet transform and a synergistic statistical model to exploit MRI structural images to improve the resolution of [11C]PIB PET myelin imaging. MM-RR performance was tested on a phantom acquisition and in a dataset comprising [11C]PIB PET and MR T1- and T2-weighted images of 8 healthy controls and 20 MS patients. For the control group, the MM-RR PET images showed an average increase of 5.7% in WM uptake while the grey-matter (GM) uptake remained constant, resulting in +31% WM/GM contrast. Furthermore, MM-RR PET binding maps correlated significantly with the mRNA expressions of the most represented proteins in the myelin sheath (R2 = 0.57 ± 0.09). In the patient group, MM-RR PET images showed sharper lesion contours and significant improvement in normal-appearing tissue/WM-lesion contrast compared to standard PET (contrast improvement > +40%). These results were consistent with MM-RR performances in phantom experiments.
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Affiliation(s)
- Elisabetta Grecchi
- 1 Centre for Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Mattia Veronese
- 1 Centre for Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Benedetta Bodini
- 2 Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225, INSERM, Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, UPMC Paris, France.,3 Service Hospitalier Fréderic Joliot, SHFJ, Orsay, France
| | - Daniel García-Lorenzo
- 2 Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225, INSERM, Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, UPMC Paris, France
| | - Marco Battaglini
- 4 Department of Neurological and Behavioural Sciences, University of Siena, Siena, Italy
| | - Bruno Stankoff
- 2 Institut du Cerveau et de la Moelle épinière (ICM), CNRS UMR 7225, INSERM, Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Hôpital de la Pitié Salpêtrière, Sorbonne Universités, UPMC Paris, France.,3 Service Hospitalier Fréderic Joliot, SHFJ, Orsay, France.,4 Department of Neurological and Behavioural Sciences, University of Siena, Siena, Italy
| | - Federico E Turkheimer
- 1 Centre for Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Bhattacharyya S, Egerton A, Kim E, Rosso L, Riano Barros D, Hammers A, Brammer M, Turkheimer FE, Howes OD, McGuire P. Acute induction of anxiety in humans by delta-9-tetrahydrocannabinol related to amygdalar cannabinoid-1 (CB1) receptors. Sci Rep 2017; 7:15025. [PMID: 29101333 PMCID: PMC5670208 DOI: 10.1038/s41598-017-14203-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 10/04/2017] [Indexed: 12/19/2022] Open
Abstract
Use of Cannabis, the most widely used illicit drug worldwide, is associated with acute anxiety, and anxiety disorders following regular use. The precise neural and receptor basis of these effects have not been tested in man. Employing a combination of functional MRI (fMRI) and positron emission tomography (PET), we investigated whether the effects of delta-9-tetrahydrocannabinol (delta-9-THC), the main psychoactive ingredient of cannabis, on anxiety and on amygdala response while processing fearful stimuli were related to local availability of its main central molecular target, cannabinoid-1 (CB1) receptors in man. Fourteen healthy males were studied with fMRI twice, one month apart, following an oral dose of either delta-9-THC (10 mg) or placebo, while they performed a fear-processing task. Baseline availability of the CB1 receptor was studied using PET with [11C]MePPEP, a CB1 inverse agonist radioligand. Relative to the placebo condition, delta-9-THC induced anxiety and modulated right amygdala activation while processing fear. Both these effects were positively correlated with CB1 receptor availability in the right amygdala. These results suggest that the acute effects of cannabis on anxiety in males are mediated by the modulation of amygdalar function by delta-9-THC and the extent of these effects are related to local availability of CB1 receptors.
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Affiliation(s)
- Sagnik Bhattacharyya
- Department of Psychosis Studies, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK.
| | - Alice Egerton
- Department of Psychosis Studies, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK
| | - Euitae Kim
- Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Lula Rosso
- Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | | | - Alexander Hammers
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, 4th floor Lambeth Wing, St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Michael Brammer
- Department of Neuroimaging, Centre for Neuroimaging Sciences, PO Box 089, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Centre for Neuroimaging Sciences, PO Box 089, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK
| | - Oliver D Howes
- Department of Psychosis Studies, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK
- Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | - Philip McGuire
- Department of Psychosis Studies, King's College London, Institute of Psychiatry, Psychology & Neuroscience, De Crespigny Park, London, SE5 8AF, UK
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Hellyer PJ, Clopath C, Kehagia AA, Turkheimer FE, Leech R. From homeostasis to behavior: Balanced activity in an exploration of embodied dynamic environmental-neural interaction. PLoS Comput Biol 2017; 13:e1005721. [PMID: 28837556 PMCID: PMC5587328 DOI: 10.1371/journal.pcbi.1005721] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/06/2017] [Accepted: 08/09/2017] [Indexed: 12/20/2022] Open
Abstract
In recent years, there have been many computational simulations of spontaneous neural dynamics. Here, we describe a simple model of spontaneous neural dynamics that controls an agent moving in a simple virtual environment. These dynamics generate interesting brain-environment feedback interactions that rapidly destabilize neural and behavioral dynamics demonstrating the need for homeostatic mechanisms. We investigate roles for homeostatic plasticity both locally (local inhibition adjusting to balance excitatory input) as well as more globally (regional "task negative" activity that compensates for "task positive", sensory input in another region) balancing neural activity and leading to more stable behavior (trajectories through the environment). Our results suggest complementary functional roles for both local and macroscale mechanisms in maintaining neural and behavioral dynamics and a novel functional role for macroscopic "task-negative" patterns of activity (e.g., the default mode network).
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Affiliation(s)
- Peter John Hellyer
- Department of Bioengineering, Imperial College London, London, United Kingdom
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Claudia Clopath
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Angie A. Kehagia
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Federico E. Turkheimer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Robert Leech
- Computational, Cognitive and Clinical Neuroimaging Laboratory (C3NL), Imperial College London, Hammersmith Hospital, London, United Kingdom
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Hellyer PJ, Barry EF, Pellizzon A, Veronese M, Rizzo G, Tonietto M, Schütze M, Brammer M, Aurélio Romano-Silva M, Bertoldo A, Turkheimer FE. Protein synthesis is associated with high-speed dynamics and broad-band stability of functional hubs in the brain. Neuroimage 2017; 155:209-216. [PMID: 28465163 PMCID: PMC5519503 DOI: 10.1016/j.neuroimage.2017.04.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 04/10/2017] [Accepted: 04/26/2017] [Indexed: 01/30/2023] Open
Abstract
L-[1-11C]leucine PET can be used to measure in vivo protein synthesis in the brain. However, the relationship between regional protein synthesis and on-going neural dynamics is unclear. We use a graph theoretical approach to examine the relationship between cerebral protein synthesis (rCPS) and both static and dynamical measures of functional connectivity (measured using resting state functional MRI, R-fMRI). Our graph theoretical analysis demonstrates a significant positive relationship between protein turnover and static measures of functional connectivity. We compared these results to simple measures of metabolism in the cortex using [18F]FDG PET). Whilst some relationships between [18F]FDG binding and graph theoretical measures was present, there remained a significant relationship between protein turnover and graph theoretical measures, which were more robustly explained by L-[1-11C]Leucine than [18F]FDG PET. This relationship was stronger in dynamics at a faster temporal resolution relative to dynamics measured over a longer epoch. Using a Dynamic connectivity approach, we also demonstrate that broad-band dynamic measures of Functional Connectivity (FC), are inversely correlated with protein turnover, suggesting greater stability of FC in highly interconnected hub regions is supported by protein synthesis. Overall, we demonstrate that cerebral protein synthesis has a strong relationship independent of tissue metabolism to neural dynamics at the macroscopic scale. Spontaneous, neural dynamics are fundamental for information processing & function We combine L-[1-11C]leucine PET with Static and Dynamic measures of network topology ‘Hub’ brain regions are linked to increased protein synthesis, independent of tissue metabolism Stability of network hubs is inversely correlated with protein turnover Strong, stable hubs are supported by protein synthesis
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Affiliation(s)
- Peter J Hellyer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Department of Bioengineering, Imperial College London, Royal School of Mines, Room 4.35, South Kensington Campus, SW7 2AZ, UK
| | - Erica F Barry
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Alberto Pellizzon
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Mattia Veronese
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Gaia Rizzo
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Matteo Tonietto
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Manuel Schütze
- Instituto Nacional de Ciência e Tecnologia em Medicina Molecular, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Michael Brammer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Instituto Nacional de Ciência e Tecnologia em Medicina Molecular, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Marco Aurélio Romano-Silva
- Instituto Nacional de Ciência e Tecnologia em Medicina Molecular, Federal University of Minas Gerais, Belo Horizonte, Brazil; Mental Health Department, Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | | | - Federico E Turkheimer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
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Castellaro M, Rizzo G, Tonietto M, Veronese M, Turkheimer FE, Chappell MA, Bertoldo A. A Variational Bayesian inference method for parametric imaging of PET data. Neuroimage 2017; 150:136-149. [PMID: 28213113 DOI: 10.1016/j.neuroimage.2017.02.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/22/2017] [Accepted: 02/04/2017] [Indexed: 12/15/2022] Open
Abstract
In dynamic Positron Emission Tomography (PET) studies, compartmental models provide the richest information on the tracer kinetics of the tissue. Inverting such models at the voxel level is however quite challenging due to the low signal-to-noise ratio of the time activity curves. In this study, we propose the use of a Variational Bayesian (VB) approach to efficiently solve this issue and thus obtain robust quantitative parametric maps. VB was adapted to the non-uniform noise distribution of PET data. Moreover, we propose a novel hierarchical scheme to define the model parameter priors directly from the images in case such information are not available from the literature, as often happens with new PET tracers. VB was initially tested on synthetic data generated using compartmental models of increasing complexity, providing accurate (%bias<2%±2%, root mean square error<15%±5%) parameter estimates. When applied to real data on a paradigmatic set of PET tracers (L-[1-11C]leucine, [11C]WAY100635 and [18F]FDG), VB was able to generate reliable parametric maps even in presence of high noise in the data (unreliable estimates<11%±5%).
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Affiliation(s)
- M Castellaro
- Department of Information Engineering, University of Padova, Italy
| | - G Rizzo
- Department of Information Engineering, University of Padova, Italy
| | - M Tonietto
- Department of Information Engineering, University of Padova, Italy
| | - M Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - F E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - M A Chappell
- Institute of Biomedical Engineering, University of Oxford, Old Road Campus Research Building, Old Road Campus, Headington, Oxford, United Kingdom
| | - A Bertoldo
- Department of Information Engineering, University of Padova, Italy.
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McGinnity CJ, Riaño Barros DA, Rosso L, Veronese M, Rizzo G, Bertoldo A, Hinz R, Turkheimer FE, Koepp MJ, Hammers A. Test-retest reproducibility of quantitative binding measures of [ 11C]Ro15-4513, a PET ligand for GABA A receptors containing alpha5 subunits. Neuroimage 2017; 152:270-282. [PMID: 28292717 PMCID: PMC5440177 DOI: 10.1016/j.neuroimage.2016.12.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 11/20/2016] [Accepted: 12/14/2016] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION Alteration of γ-aminobutyric acid "A" (GABAA) receptor-mediated neurotransmission has been associated with various neurological and psychiatric disorders. [11C]Ro15-4513 is a PET ligand with high affinity for α5-subunit-containing GABAA receptors, which are highly expressed in limbic regions of the human brain (Sur et al., 1998). We quantified the test-retest reproducibility of measures of [11C]Ro15-4513 binding derived from six different quantification methods (12 variants). METHODS Five healthy males (median age 40 years, range 38-49 years) had a 90-min PET scan on two occasions (median interval 12 days, range 11-30 days), after injection of a median dose of 441 MegaBequerels of [11C]Ro15-4513. Metabolite-corrected arterial plasma input functions (parent plasma input functions, ppIFs) were generated for all scans. We quantified regional binding using six methods (12 variants), some of which were region-based (applied to the average time-activity curve within a region) and others were voxel-based: 1) Models requiring arterial ppIFs - regional reversible compartmental models with one and two tissue compartments (2kbv and 4kbv); 2) Regional and voxelwise Logan's graphical analyses (Logan et al., 1990), which required arterial ppIFs; 3) Model-free regional and voxelwise (exponential) spectral analyses (SA; (Cunningham and Jones, 1993)), which also required arterial ppIFs; 4) methods not requiring arterial ppIFs - voxelwise standardised uptake values (Kenney et al., 1941), and regional and voxelwise simplified reference tissue models (SRTM/SRTM2) using brainstem or alternatively cerebellum as pseudo-reference regions (Lammertsma and Hume, 1996; Gunn et al., 1997). To compare the variants, we sampled the mean values of the outcome parameters within six bilateral, non-reference grey matter regions-of-interest. Reliability was quantified in terms of median absolute percentage test-retest differences (MA-TDs; preferentially low) and between-subject coefficient of variation (BS-CV, preferentially high), both compounded by the intraclass correlation coefficient (ICC). These measures were compared between variants, with particular interest in the hippocampus. RESULTS Two of the six methods (5/12 variants) yielded reproducible data (i.e. MA-TD <10%): regional SRTMs and voxelwise SRTM2s, both using either the brainstem or the cerebellum; and voxelwise SA. However, the SRTMs using the brainstem yielded a lower median BS-CV (7% for regional, 7% voxelwise) than the other variants (8-11%), resulting in lower ICCs. The median ICCs across six regions were 0.89 (interquartile range 0.75-0.90) for voxelwise SA, 0.71 (0.64-0.84) for regional SRTM-cerebellum and 0.83 (0.70-0.86) for voxelwise SRTM-cerebellum. The ICCs for the hippocampus were 0.89 for voxelwise SA, 0.95 for regional SRTM-cerebellum and 0.93 for voxelwise SRTM-cerebellum. CONCLUSION Quantification of [11C]Ro15-4513 binding shows very good to excellent reproducibility with SRTM and with voxelwise SA which, however, requires an arterial ppIF. Quantification in the α5 subunit-rich hippocampus is particularly reliable. The very low expression of the α5 in the cerebellum (Fritschy and Mohler, 1995; Veronese et al., 2016) and the substantial α1 subunit density in this region may hamper the application of reference tissue methods.
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Affiliation(s)
- Colm J McGinnity
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK.
| | - Daniela A Riaño Barros
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | - Lula Rosso
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK
| | - Mattia Veronese
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Gaia Rizzo
- Department of Information Engineering, University of Padova, Padova, Italy
| | | | - Rainer Hinz
- Wolfson Molecular Imaging Centre, University of Manchester, Manchester, UK
| | - Federico E Turkheimer
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Matthias J Koepp
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, UK; Epilepsy Society, Chalfont St Peter, UK
| | - Alexander Hammers
- Centre for Neuroscience, Department of Medicine, Imperial College London, London, UK; Medical Research Council Clinical Sciences Centre, Hammersmith Hospital, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK; The Neurodis Foundation, CERMEP - Imagerie du Vivant, Lyon, France
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Politis M, Lahiri N, Niccolini F, Su P, Wu K, Giannetti P, Scahill RI, Turkheimer FE, Tabrizi SJ, Piccini P. Corrigendum to "Increased central microglial activation associated with peripheral cytokine levels in premanifest Huntington's disease gene carriers" [Neurobiol. Dis. 83 (2015) 115-121]. Neurobiol Dis 2016; 98:162. [PMID: 27939917 DOI: 10.1016/j.nbd.2016.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Marios Politis
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Nayana Lahiri
- Huntington's Disease Research Group, Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
| | - Flavia Niccolini
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK; Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Paul Su
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Kit Wu
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Paolo Giannetti
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Rachael I Scahill
- Huntington's Disease Research Group, Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Sarah J Tabrizi
- Huntington's Disease Research Group, Department of Neurodegenerative Disease, Institute of Neurology, University College London, London, UK
| | - Paola Piccini
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK.
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Mouchlianitis E, Bloomfield MAP, Law V, Beck K, Selvaraj S, Rasquinha N, Waldman A, Turkheimer FE, Egerton A, Stone J, Howes OD. Treatment-Resistant Schizophrenia Patients Show Elevated Anterior Cingulate Cortex Glutamate Compared to Treatment-Responsive. Schizophr Bull 2016; 42:744-52. [PMID: 26683625 PMCID: PMC4838083 DOI: 10.1093/schbul/sbv151] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Resistance to antipsychotic treatment is a significant clinical problem in patients with schizophrenia with approximately 1 in 3 showing limited or no response to repeated treatments with antipsychotic medication. The neurobiological basis for treatment resistance is unknown but recent evidence implicates glutamatergic function in the anterior cingulate cortex. We examined glutamate levels of chronically ill treatment-resistant patients directly compared to treatment-responsive patients. METHODS We acquired proton magnetic resonance spectroscopy (1H-MRS) at 3 Tesla from 21 treatment-resistant and 20 treatment-responsive patients. All participants had a DSM-IV diagnosis of schizophrenia. Treatment-resistant patients were classified using the modified Kane criteria. The groups were matched for age, sex, smoking status, and illness duration. RESULTS Glutamate to creatine ratio levels were higher in treatment-resistant patients (Mean [SD] = 1.57 [0.24]) than in treatment-responsive patients (Mean[SD] = 1.38 [0.23]), (T[35] = 2.34, P = .025, 2-tailed), with a large effect size of d = 0.76. A model assuming 2 populations showed a 25% improvement in the fit of the Akaike weights (0.55) over a model assuming 1 population (0.44), producing group values almost identical to actual group means. DISCUSSION Increased anterior cingulate glutamate level is associated with treatment-resistant schizophrenia. This appears to be a stable neurobiological trait of treatment-resistant patients. We discuss possible explanations for glutamatergic dysfunction playing a significant role in resistance to conventional antipsychotic treatments, which are all dopamine-2 receptor blockers. Our findings suggest that glutamatergic treatments may be particularly effective in resistant patients and that 1H-MRS glutamate indices can potentially have clinical use.
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Affiliation(s)
- Elias Mouchlianitis
- Medical Research Council Clinical Sciences Centre, Psychiatric Imaging Group, Hammersmith Hospital, London, UK; Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King's College London, UK;
| | - Michael A. P. Bloomfield
- Medical Research Council Clinical Sciences Centre, Psychiatric Imaging Group, Hammersmith Hospital, London, UK;,University College London, Division of Psychiatry, London, UK
| | - Vincent Law
- Medical Research Council Clinical Sciences Centre, Psychiatric Imaging Group, Hammersmith Hospital, London, UK
| | - Katherine Beck
- Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King’s College London, UK
| | - Sudhakar Selvaraj
- Department of Psychiatry and Behavioral Sciences, University of Texas, Houston, TX
| | | | - Adam Waldman
- Division of Brain Sciences, Imperial College London, Hammersmith Hospital, London, UK
| | - Federico E. Turkheimer
- Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King’s College London, UK
| | - Alice Egerton
- Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King’s College London, UK
| | - James Stone
- Medical Research Council Clinical Sciences Centre, Psychiatric Imaging Group, Hammersmith Hospital, London, UK;,Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King’s College London, UK
| | - Oliver D. Howes
- Medical Research Council Clinical Sciences Centre, Psychiatric Imaging Group, Hammersmith Hospital, London, UK;,Institute of Psychiatry Psychology and Neuroscience, Department of Psychosis Studies, King’s College London, UK
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Roncaroli F, Su Z, Herholz K, Gerhard A, Turkheimer FE. TSPO expression in brain tumours: is TSPO a target for brain tumour imaging? Clin Transl Imaging 2016; 4:145-156. [PMID: 27077069 PMCID: PMC4820497 DOI: 10.1007/s40336-016-0168-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/07/2016] [Indexed: 02/06/2023]
Abstract
Positron emission tomography (PET) alone or in combination with MRI is increasingly assuming a central role in the development of diagnostic and therapeutic strategies for brain tumours with the aim of addressing tumour heterogeneity, assisting in patient stratification, and contributing to predicting treatment response. The 18 kDa translocator protein (TSPO) is expressed in high-grade gliomas, while its expression is comparatively low in normal brain. In addition, the evidence of elevated TSPO in neoplastic cells has led to studies investigating TSPO as a transporter of anticancer drugs for brain delivery and a selective target for tumour tissue. The TSPO therefore represents an ideal candidate for molecular imaging studies. Knowledge of the biology of TSPO in normal brain cells, in-depth understanding of TSPO functions and biodistribution in neoplastic cells, accurate methods for quantification of uptake of TSPO tracers and pharmacokinetic data regarding TSPO-targeted drugs are required before introducing TSPO PET and TSPO-targeted treatment in clinical practice. In this review, we will discuss the impact of preclinical PET studies and the application of TSPO imaging in human brain tumours, the advantages and disadvantages of TSPO imaging compared to other imaging modalities and other PET tracers, and pathology studies on the extent and distribution of TSPO in gliomas. The suitability of TSPO as molecular target for treatment of brain tumours will also be the appraised.
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Affiliation(s)
- Federico Roncaroli
- Wolfson Molecular Imaging Centre, The University of Manchester, 7 Palatine Road, Withington, Manchester, M20 3LJ UK
| | - Zhangjie Su
- Wolfson Molecular Imaging Centre, The University of Manchester, 7 Palatine Road, Withington, Manchester, M20 3LJ UK
| | - Karl Herholz
- Wolfson Molecular Imaging Centre, The University of Manchester, 7 Palatine Road, Withington, Manchester, M20 3LJ UK
| | - Alexander Gerhard
- Wolfson Molecular Imaging Centre, The University of Manchester, 7 Palatine Road, Withington, Manchester, M20 3LJ UK
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Scott G, Ramlackhansingh AF, Edison P, Hellyer P, Cole J, Veronese M, Leech R, Greenwood RJ, Turkheimer FE, Gentleman SM, Heckemann RA, Matthews PM, Brooks DJ, Sharp DJ. Amyloid pathology and axonal injury after brain trauma. Neurology 2016; 86:821-8. [PMID: 26843562 PMCID: PMC4793784 DOI: 10.1212/wnl.0000000000002413] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 09/03/2015] [Indexed: 01/20/2023] Open
Abstract
OBJECTIVE To image β-amyloid (Aβ) plaque burden in long-term survivors of traumatic brain injury (TBI), test whether traumatic axonal injury and Aβ are correlated, and compare the spatial distribution of Aβ to Alzheimer disease (AD). METHODS Patients 11 months to 17 years after moderate-severe TBI underwent (11)C-Pittsburgh compound B ((11)C-PiB)-PET, structural and diffusion MRI, and neuropsychological examination. Healthy aged controls and patients with AD underwent PET and structural MRI. Binding potential (BPND) images of (11)C-PiB, which index Aβ plaque density, were computed using an automatic reference region extraction procedure. Voxelwise and regional differences in BPND were assessed. In TBI, a measure of white matter integrity, fractional anisotropy, was estimated and correlated with (11)C-PiB BPND. RESULTS Twenty-eight participants (9 with TBI, 9 controls, 10 with AD) were assessed. Increased (11)C-PiB BPND was found in TBI vs controls in the posterior cingulate cortex and cerebellum. Binding in the posterior cingulate cortex increased with decreasing fractional anisotropy of associated white matter tracts and increased with time since injury. Compared to AD, binding after TBI was lower in neocortical regions but increased in the cerebellum. CONCLUSIONS Increased Aβ burden was observed in TBI. The distribution overlaps with, but is distinct from, that of AD. This suggests a mechanistic link between TBI and the development of neuropathologic features of dementia, which may relate to axonal damage produced by the injury.
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Affiliation(s)
- Gregory Scott
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Anil F Ramlackhansingh
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Paul Edison
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Peter Hellyer
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - James Cole
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Mattia Veronese
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Rob Leech
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Richard J Greenwood
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Federico E Turkheimer
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Steve M Gentleman
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Rolf A Heckemann
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - Paul M Matthews
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - David J Brooks
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark
| | - David J Sharp
- From the Division of Brain Sciences (G.S., A.F.R., P.E., P.H., J.C., R.L., S.M.G., R.A.H., P.M.M., D.J.B., D.J.S.), Department of Medicine, Imperial College London; Institute of Psychiatry, Psychology & Neuroscience (P.H., M.V., F.E.T.), King's College London; Institute of Neurology (R.J.G.), University College London, UK; MedTech West at Sahlgrenska University Hospital (R.A.H.), University of Gothenburg, Sweden; and Institute of Clinical Medicine (D.J.B.), Aarhus University, Denmark.
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