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Weinstein AM. A brain imaging study of dopamine receptor D 2 availability in cannabis dependent users after recovery from cannabis-induced psychosis. Front Psychiatry 2023; 14:1230760. [PMID: 37965367 PMCID: PMC10641483 DOI: 10.3389/fpsyt.2023.1230760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 10/11/2023] [Indexed: 11/16/2023] Open
Abstract
There is increased risk of psychosis associated with cannabis use disorder and the interaction of THC with dopamine neurotransmission is complex. It is important to investigate the recovery from cannabis-induced psychosis and its effects on the brain's dopamine neurotransmission. This study was to evaluate dopamine receptor D2 availability in the striatum (caudate/putamen) in recently abstinent cannabis dependent users after recovery from psychosis in comparison with abstinent MDMA "ecstasy" abusers and healthy control participants. Participants were eight abstinent ex cannabis-dependent users who were treated for cannabis-induced psychosis with anti-psychotic medication and psychosocial support for 4 months in an inpatient treatment center for drug users. They were compared with nine abstinent ex MDMA "ecstasy" abusers who received medication and psycho-social treatment for 4 months at the same treatment facility and eight healthy control participants. All participants were scanned with bolus and constant infusion of [123I] Iodobenzamide (IBZM) in Single Photon Computed Tomography (SPECT). Cannabis abstinent users who were treated for cannabis-induced psychotic episodes showed no difference in dopamine D2 receptor availability in the caudate compared with abstinent MDMA "ecstasy" abusers and healthy control participants. This finding indicates minimal effects of cannabis-induced psychosis on dopamine reward mechanisms. There is evidence for reduced D2 receptor availability measures in the right putamen (uncorrected) which may indicate a residual effect of anti-psychotic medication.
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Affiliation(s)
- Aviv M. Weinstein
- Department of Psychology and Behavioral Science, Ariel University, Ariel, Israel
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2
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Baker A, Suetani S, Cosgrove P, Siskind D, Murray GK, Scott JG, Kesby JP. Reversal learning in those with early psychosis features contingency-dependent changes in loss response and learning. Cogn Neuropsychiatry 2023; 28:342-360. [PMID: 37737715 DOI: 10.1080/13546805.2023.2259019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 09/07/2023] [Indexed: 09/23/2023]
Abstract
INTRODUCTION People with psychotic disorders commonly feature broad decision-making impairments that impact their functional outcomes. Specific associative/reinforcement learning problems have been demonstrated in persistent psychosis. But these phenotypes may differ in early psychosis, suggesting that aspects of cognition decline over time. METHODS The present proof-of-concept study examined goal-directed action and reversal learning in controls and those with early psychosis. RESULTS Equivalent performance was observed between groups during outcome-specific devaluation, and reversal learning at an 80:20 contingency (reward probability for high:low targets). But when the low target reward probability was increased (80:40) those with early psychosis altered their response to loss, whereas controls did not. Computational modelling confirmed that in early psychosis there was a change in punishment learning that increased the chance of staying with the same stimulus after a loss, multiple trials into the future. In early psychosis, the magnitude of this response was greatest in those with higher IQ and lower clinical severity scores. CONCLUSIONS We show preliminary evidence that those with early psychosis present with a phenotype that includes altered responding to loss and hyper-adaptability in response to outcome changes. This may reflect a compensatory response to overcome the milieu of corticostriatal changes associated with psychotic disorders.
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Affiliation(s)
- Andrea Baker
- Queensland Centre for Mental Health Research, Brisbane, Australia
| | - Shuichi Suetani
- Queensland Centre for Mental Health Research, Brisbane, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
- School of Medicine and Dentistry, Griffith University, Brisbane, Australia
- Institute for Urban Indigenous Health, Brisbane, Australia
| | - Peter Cosgrove
- Queensland Centre for Mental Health Research, Brisbane, Australia
| | - Dan Siskind
- Queensland Centre for Mental Health Research, Brisbane, Australia
- Metro South Addiction and Mental Health Services, Brisbane, Australia
- Faculty of Medicine, University of Queensland, Brisbane, Australia
| | - Graham K Murray
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - James G Scott
- Queensland Centre for Mental Health Research, Brisbane, Australia
- Child Health Research Centre, University of Queensland, Brisbane, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - James P Kesby
- Queensland Centre for Mental Health Research, Brisbane, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
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3
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Grunze H. The role of the D3 dopamine receptor and its partial agonist cariprazine in patients with schizophrenia and substance use disorder. Expert Opin Pharmacother 2023; 24:1985-1992. [PMID: 37817489 DOI: 10.1080/14656566.2023.2266359] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 09/29/2023] [Indexed: 10/12/2023]
Abstract
INTRODUCTION Comorbidity of substance use disorder (SUD) with schizophrenia, referred to as dual disorder (DD), significantly increases morbidity and mortality compared to schizophrenia alone. A dopaminergic dysregulation seems to be a common pathophysiological basis of the comorbidity. AREAS COVERED This article reports the current evidence on the role of dopamine dysregulations in DD, the pharmacological profile of cariprazine, a partial agonist of D3 and D2 dopamine receptors, and first clinical observations that may support its usefulness in the therapy of DD. PubMed/MEDLINE was searched for the keywords 'cariprazine,' 'schizophrenia,' 'dual disorder,' 'dopamine,' and 'dopamine receptor.' Preclinical and clinical studies, and reviews published in English were retrieved. EXPERT OPINION Although the management of DD remains challenging, and the evidence for pharmacologic treatments is still unsatisfactory, cariprazine may be a candidate medication in DD due to its unique mechanism of action. Preliminary clinical experiences suggest that cariprazine has both antipsychotic and anticraving properties and should be considered early in patients with DD.
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Affiliation(s)
- Heinz Grunze
- Psychiatrie Schwäbisch Hall, Schwäbisch Hall, Germany
- Department of Psychiatry, Paracelsus Medical University Nuremberg, Nuremberg, Germany
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4
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Zrenner B, Zrenner C, Balderston N, Blumberger DM, Kloiber S, Laposa JM, Tadayonnejad R, Trevizol AP, Zai G, Feusner JD. Toward personalized circuit-based closed-loop brain-interventions in psychiatry: using symptom provocation to extract EEG-markers of brain circuit activity. Front Neural Circuits 2023; 17:1208930. [PMID: 37671039 PMCID: PMC10475600 DOI: 10.3389/fncir.2023.1208930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/31/2023] [Indexed: 09/07/2023] Open
Abstract
Symptom provocation is a well-established component of psychiatric research and therapy. It is hypothesized that specific activation of those brain circuits involved in the symptomatic expression of a brain pathology makes the relevant neural substrate accessible as a target for therapeutic interventions. For example, in the treatment of obsessive-compulsive disorder (OCD), symptom provocation is an important part of psychotherapy and is also performed prior to therapeutic brain stimulation with transcranial magnetic stimulation (TMS). Here, we discuss the potential of symptom provocation to isolate neurophysiological biomarkers reflecting the fluctuating activity of relevant brain networks with the goal of subsequently using these markers as targets to guide therapy. We put forward a general experimental framework based on the rapid switching between psychiatric symptom states. This enable neurophysiological measures to be derived from EEG and/or TMS-evoked EEG measures of brain activity during both states. By subtracting the data recorded during the baseline state from that recorded during the provoked state, the resulting contrast would ideally isolate the specific neural circuits differentially activated during the expression of symptoms. A similar approach enables the design of effective classifiers of brain activity from EEG data in Brain-Computer Interfaces (BCI). To obtain reliable contrast data, psychiatric state switching needs to be achieved multiple times during a continuous recording so that slow changes of brain activity affect both conditions equally. This is achieved easily for conditions that can be controlled intentionally, such as motor imagery, attention, or memory retention. With regard to psychiatric symptoms, an increase can often be provoked effectively relatively easily, however, it can be difficult to reliably and rapidly return to a baseline state. Here, we review different approaches to return from a provoked state to a baseline state and how these may be applied to different symptoms occurring in different psychiatric disorders.
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Affiliation(s)
- Brigitte Zrenner
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada
- University Psychiatry Hospital, University of Tübingen, Tübingen, Germany
| | - Christoph Zrenner
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute for Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- University Neurology Hospital, University of Tübingen, Tübingen, Germany
| | - Nicholas Balderston
- Center for Neuromodulation in Depression and Stress (CNDS), Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Daniel M. Blumberger
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Stefan Kloiber
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Judith M. Laposa
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Reza Tadayonnejad
- TMS Clinical and Research Service, Neuromodulation Division, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, United States
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States
- Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA, United States
| | - Alisson Paulino Trevizol
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Gwyneth Zai
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Jamie D. Feusner
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, United States
- Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA, United States
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
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5
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Rabiner EA, Uz T, Mansur A, Brown T, Chen G, Wu J, Atienza J, Schwarz AJ, Yin W, Lewis Y, Searle GE, Dennison JMTJ, Passchier J, Gunn RN, Tauscher J. Endogenous dopamine release in the human brain as a pharmacodynamic biomarker: evaluation of the new GPR139 agonist TAK-041 with [ 11C]PHNO PET. Neuropsychopharmacology 2022; 47:1405-1412. [PMID: 34675381 PMCID: PMC9117280 DOI: 10.1038/s41386-021-01204-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Revised: 09/03/2021] [Accepted: 09/29/2021] [Indexed: 01/01/2023]
Abstract
The use of positron emission tomography (PET) in early-phase development of novel drugs targeting the central nervous system, is well established for the evaluation of brain penetration and target engagement. However, when novel targets are involved a suitable PET ligand is not always available. We demonstrate an alternative approach that evaluates the attenuation of amphetamine-induced synaptic dopamine release by a novel agonist of the orphan G-protein-coupled receptor GPR139 (TAK-041). GPR139 agonism is a novel candidate mechanism for the treatment of schizophrenia and other disorders associated with social and cognitive dysfunction. Ten healthy volunteers underwent [11C]PHNO PET at baseline, and twice after receiving an oral dose of d-amphetamine (0.5 mg/kg). One of the post-d-amphetamine scans for each subject was preceded by a single oral dose of TAK-041 (20 mg in five; 40 mg in the other five participants). D-amphetamine induced a significant decrease in [11C]PHNO binding potential relative to the non-displaceable component (BPND) in all regions examined (16-28%), consistent with increased synaptic dopamine release. Pre-treatment with TAK-041 significantly attenuated the d-amphetamine-induced reduction in BPND in the a priori defined regions (putamen and ventral striatum: 26% and 18%, respectively). The reduction in BPND was generally higher after the 40 mg than the 20 mg TAK-041 dose, with the difference between doses reaching statistical significance in the putamen. Our findings suggest that TAK-041 enters the human brain and interacts with GPR139 to affect endogenous dopamine release. [11C]PHNO PET is a practical method to detect the effects of novel drugs on the brain dopaminergic system in healthy volunteers, in the early stages of drug development.
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Affiliation(s)
- Eugenii A. Rabiner
- grid.498414.40000 0004 0548 3187Invicro, London, UK ,grid.13097.3c0000 0001 2322 6764Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Tolga Uz
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Ayla Mansur
- grid.498414.40000 0004 0548 3187Invicro, London, UK
| | - Terry Brown
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Grace Chen
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Jingtao Wu
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Joy Atienza
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Adam J. Schwarz
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Wei Yin
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
| | - Yvonne Lewis
- grid.498414.40000 0004 0548 3187Invicro, London, UK
| | | | | | | | | | - Johannes Tauscher
- grid.419849.90000 0004 0447 7762Takeda Pharmaceuticals Ltd, Cambridge, MA USA
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Rogóż Z, Kamińska K, Lech MA, Lorenc-Koci E. N-Acetylcysteine and Aripiprazole Improve Social Behavior and Cognition and Modulate Brain BDNF Levels in a Rat Model of Schizophrenia. Int J Mol Sci 2022; 23:ijms23042125. [PMID: 35216241 PMCID: PMC8877560 DOI: 10.3390/ijms23042125] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/18/2022] [Accepted: 02/11/2022] [Indexed: 02/01/2023] Open
Abstract
Treatment of negative symptoms and cognitive disorders in patients with schizophrenia is still a serious clinical problem. The aim of our study was to compare the efficacy of chronic administration of the atypical antipsychotic drug aripiprazole (7-{4-[4-(2,3-dichlorophenyl)-1-piperazinyl] butoxy}-3,4-dihydro-2(1H)-quinolinone; ARI) and the well-known antioxidant N-acetylcysteine (NAC) both in alleviating schizophrenia-like social and cognitive deficits and in reducing the decreases in the levels of the brain-derived neurotrophic factor (BDNF) in the prefrontal cortex (PFC) and hippocampus (HIP) of adult Sprague-Dawley rats, that have been induced by chronic administration of the model compound L-buthionine-(S, R)-sulfoximine (BSO) during the early postnatal development (p5–p16). ARI was administered at doses of 0.1 and 0.3 mg/kg while NAC at doses of 10 and 30 mg/kg, alone or in combination. Administration of higher doses of ARI or NAC alone, or co-treatment with lower, ineffective doses of these drugs significantly improved social and cognitive performance as assessed in behavioral tests. Both doses of NAC and 0.3 mg/kg of ARI increased the expression of BDNF mRNA in the PFC, while all doses of these drugs and their combinations enhanced the levels of BDNF protein in this brain structure. In the HIP, only 0,3 mg/kg ARI increased the levels of both BDNF mRNA and its protein. These data show that in the rat BSO-induced neurodevelopmental model of schizophrenia, ARI and NAC differently modulated BDNF levels in the PFC and HIP.
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Affiliation(s)
- Zofia Rogóż
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (Z.R.); (K.K.); (M.A.L.)
| | - Kinga Kamińska
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (Z.R.); (K.K.); (M.A.L.)
| | - Marta Anna Lech
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (Z.R.); (K.K.); (M.A.L.)
| | - Elżbieta Lorenc-Koci
- Department of Neuro-Psychopharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland
- Correspondence: ; Tel.: +48-126-623-272
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7
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Clinical correlation but no elevation of striatal dopamine synthesis capacity in two independent cohorts of medication-free individuals with schizophrenia. Mol Psychiatry 2022; 27:1241-1247. [PMID: 34789848 DOI: 10.1038/s41380-021-01337-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 09/03/2021] [Accepted: 10/01/2021] [Indexed: 11/08/2022]
Abstract
Dysregulation of dopamine systems has been considered a foundational driver of pathophysiological processes in schizophrenia, an illness characterized by diverse domains of symptomatology. Prior work observing elevated presynaptic dopamine synthesis capacity in some patient groups has not always identified consistent symptom correlates, and studies of affected individuals in medication-free states have been challenging to obtain. Here we report on two separate cohorts of individuals with schizophrenia spectrum illness who underwent blinded medication withdrawal and medication-free neuroimaging with [18F]-FDOPA PET to assess striatal dopamine synthesis capacity. Consistently in both cohorts, we found no significant differences between patient and matched, healthy comparison groups; however, we did identify and replicate robust inverse relationships between negative symptom severity and tracer-specific uptake widely throughout the striatum: [18F]-FDOPA specific uptake was lower in patients with a greater preponderance of negative symptoms. Complementary voxel-wise and region of interest analyses, both with and without partial volume correction, yielded consistent results. These data suggest that for some individuals, striatal hyperdopaminergia may not be a defining or enduring feature of primary psychotic illness. However, clinical differences across individuals may be significantly linked to variability in striatal dopaminergic tone. These findings call for further experimentation aimed at parsing the heterogeneity of dopaminergic systems function in schizophrenia.
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8
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Evaluating the evidence for sex differences: a scoping review of human neuroimaging in psychopharmacology research. Neuropsychopharmacology 2022; 47:430-443. [PMID: 34732844 PMCID: PMC8674314 DOI: 10.1038/s41386-021-01162-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 07/12/2021] [Accepted: 08/13/2021] [Indexed: 01/03/2023]
Abstract
Although sex differences in psychiatric disorders abound, few neuropsychopharmacology (NPP) studies consider sex as a biological variable (SABV). We conducted a scoping review of this literature in humans by systematically searching PubMed to identify peer-reviewed journal articles published before March 2020 that (1) studied FDA-approved medications used to treat psychiatric disorders (or related symptoms) and (2) adequately evaluated sex differences using in vivo neuroimaging methodologies. Of the 251 NPP studies that included both sexes and considered SABV in analyses, 80% used methodologies that eliminated the effect of sex (e.g., by including sex as a covariate to control for its effect). Only 20% (50 studies) adequately evaluated sex differences either by testing for an interaction involving sex or by stratifying analyses by sex. Of these 50 studies, 72% found statistically significant sex differences in at least one outcome. Sex differences in neural and behavioral outcomes were studied more often in drugs indicated for conditions with known sex differences. Likewise, the majority of studies conducted in those drug classes noted sex differences: antidepressants (13 of 16), antipsychotics (10 of 12), sedative-hypnotics (6 of 10), and stimulants (6 of 10). In contrast, only two studies of mood stabilizers evaluated SABV, with one noting a sex difference. By mapping this literature, we bring into sharp relief how few studies adequately evaluate sex differences in NPP studies. Currently, all NIH-funded studies are required to consider SABV. We urge scientific journals, peer reviewers, and regulatory agencies to require researchers to consider SABV in their research. Continuing to ignore SABV in NPP research has ramifications both in terms of rigor and reproducibility of research, potentially leading to costly consequences and unrealized benefits.
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9
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Elevated endogenous GDNF induces altered dopamine signalling in mice and correlates with clinical severity in schizophrenia. Mol Psychiatry 2022; 27:3247-3261. [PMID: 35618883 PMCID: PMC9708553 DOI: 10.1038/s41380-022-01554-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 11/08/2022]
Abstract
Presynaptic increase in striatal dopamine is the primary dopaminergic abnormality in schizophrenia, but the underlying mechanisms are not understood. Here, we hypothesized that increased expression of endogenous GDNF could induce dopaminergic abnormalities that resemble those seen in schizophrenia. To test the impact of GDNF elevation, without inducing adverse effects caused by ectopic overexpression, we developed a novel in vivo approach to conditionally increase endogenous GDNF expression. We found that a 2-3-fold increase in endogenous GDNF in the brain was sufficient to induce molecular, cellular, and functional changes in dopamine signalling in the striatum and prefrontal cortex, including increased striatal presynaptic dopamine levels and reduction of dopamine in prefrontal cortex. Mechanistically, we identified adenosine A2a receptor (A2AR), a G-protein coupled receptor that modulates dopaminergic signalling, as a possible mediator of GDNF-driven dopaminergic abnormalities. We further showed that pharmacological inhibition of A2AR with istradefylline partially normalised striatal GDNF and striatal and cortical dopamine levels in mice. Lastly, we found that GDNF levels are increased in the cerebrospinal fluid of first episode psychosis patients, and in post-mortem striatum of schizophrenia patients. Our results reveal a possible contributor for increased striatal dopamine signalling in a subgroup of schizophrenia patients and suggest that GDNF-A2AR crosstalk may regulate dopamine function in a therapeutically targetable manner.
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Danielsson K, Stomberg R, Adermark L, Ericson M, Söderpalm B. Differential dopamine release by psychosis-generating and non-psychosis-generating addictive substances in the nucleus accumbens and dorsomedial striatum. Transl Psychiatry 2021; 11:472. [PMID: 34518523 PMCID: PMC8438030 DOI: 10.1038/s41398-021-01589-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 08/16/2021] [Accepted: 08/26/2021] [Indexed: 02/08/2023] Open
Abstract
Schizophrenia is associated with three main categories of symptoms; positive, negative and cognitive. Of these, only the positive symptoms respond well to treatment with antipsychotics. Due to the lack of effect of antipsychotics on negative symptoms, it has been suggested that while the positive symptoms are related to a hyperdopaminergic state in associative striatum, the negative symptoms may be a result of a reduced dopamine (DA) activity in the nucleus accumbens (nAc). Drug abuse is common in schizophrenia, supposedly alleviating negative symptomatology. Some, but not all, drugs aggravate psychosis, tentatively due to differential effects on DA activity in striatal regions. Here this hypothesis was tested in rats by using a double-probe microdialysis technique to simultaneously assess DA release in the nAc and associative striatum (dorsomedial striatum; DMS) following administration of the psychosis-generating substances amphetamine (0.5 mg/kg), cocaine (15 mg/kg) and Δ9-tetrahydrocannabinol (THC, 3 mg/kg), and the generally non-psychosis-generating substances ethanol (2.5 g/kg), nicotine (0.36 mg/kg) and morphine (5 mg/kg). The data show that amphetamine and cocaine produce identical DA elevations both in the nAc and DMS, whereas nicotine increases DA in nAc only. Ethanol and morphine both increased DMS DA, but weaker and in a qualitatively different way than in nAc, suggesting that the manner in which DA is increased might be important to the triggering of psychosis. THC elevated DA in neither region, indicating that the pro-psychotic effects of THC are not related to DA release. We conclude that psychosis-generating substances affect striatal DA release differently than non-psychosis-generating substances.
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Affiliation(s)
- Klara Danielsson
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Rosita Stomberg
- grid.8761.80000 0000 9919 9582Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Louise Adermark
- grid.8761.80000 0000 9919 9582Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden ,grid.8761.80000 0000 9919 9582Department of Pharmacology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Mia Ericson
- grid.8761.80000 0000 9919 9582Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Bo Söderpalm
- grid.8761.80000 0000 9919 9582Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden ,grid.1649.a000000009445082XBeroendekliniken, Sahlgrenska University Hospital, Gothenburg, Sweden
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11
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Aryutova K, Stoyanov D. Pharmaco-Magnetic Resonance as a Tool for Monitoring the Medication-Related Effects in the Brain May Provide Potential Biomarkers for Psychotic Disorders. Int J Mol Sci 2021; 22:9309. [PMID: 34502214 PMCID: PMC8430741 DOI: 10.3390/ijms22179309] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 08/19/2021] [Accepted: 08/25/2021] [Indexed: 01/04/2023] Open
Abstract
The neurodegenerative and neurodevelopmental hypotheses represent the basic etiological framework for the origin of schizophrenia. Additionally, the dopamine hypothesis, adopted more than two decades ago, has repeatedly asserted the position of dopamine as a pathobiochemical substrate through the action of psychostimulants and neuroleptics on the mesolimbic and mesocortical systems, giving insight into the origin of positive and negative schizophrenic symptoms. Meanwhile, cognitive impairments in schizophrenia remain incompletely understood but are thought to be present during all stages of the disease, as well as in the prodromal, interictal and residual phases. On the other hand, observations on the effects of NMDA antagonists, such as ketamine and phencyclidine, reveal that hypoglutamatergic neurotransmission causes not only positive and negative but also cognitive schizophrenic symptoms. This review aims to summarize the different hypotheses about the origin of psychoses and to identify the optimal neuroimaging method that can serve to unite them in an integral etiological framework. We systematically searched Google scholar (with no concern to the date published) to identify studies investigating the etiology of schizophrenia, with a focus on impaired central neurotransmission. The complex interaction between the dopamine and glutamate neurotransmitter systems provides the long-needed etiological concept, which combines the neurodegenerative hypothesis with the hypothesis of impaired neurodevelopment in schizophrenia. Pharmaco-magnetic resonance imaging is a neuroimaging method that can provide a translation of scientific knowledge about the neural networks and the disruptions in and between different brain regions, into clinically applicable and effective therapeutic results in the management of severe psychotic disorders.
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Affiliation(s)
| | - Drozdstoy Stoyanov
- Department of Psychiatry and Medical Psychology, Research Institute, Medical University Plovdiv, 4002 Plovdiv, Bulgaria;
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12
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Ciobanu AM, Geza L, David IG, Popa DE, Buleandra M, Ciucu AA, Dehelean L. Actualities in immunological markers and electrochemical sensors for determination of dopamine and its metabolites in psychotic disorders (Review). Exp Ther Med 2021; 22:888. [PMID: 34194566 PMCID: PMC8237259 DOI: 10.3892/etm.2021.10320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 05/26/2021] [Indexed: 12/03/2022] Open
Abstract
Psychotic disorders represent a serious health concern. At this moment, anamnestic data, international criteria for diagnosis/classification from the Diagnostic and Statistical Manual of Mental Disorders-5 and the International Classification of Diseases-10 and diagnostic scales are used to establish a diagnosis. The most commonly used biomarkers in psychotic illnesses are those regarding the neuroimmune system, metabolic abnormalities, neurotrophins and neurotransmitter systems and proteomics. A current issue faced by clinicians is the lack of biomarkers to help develop a more accurate diagnosis, with the possibility of initiating the most effective treatment. The detection of biological markers for psychosis has the potential to contribute to improvements in its diagnosis, prognosis and treatment effectiveness. The mixture of multiple biomarkers may improve the ability to differentiate and classify these patients. In this sense, the aim of this study was to analyze the literature concerning the potential biomarkers that could be used in medical practice and to review the newest developments in electrochemical sensors used for dopamine detection, one of the most important exploited biomarkers.
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Affiliation(s)
- Adela Magdalena Ciobanu
- Department of Psychiatry, 'Prof. Dr. Alexandru Obregia' Clinical Psychiatric Hospital, 041914 Bucharest, Romania.,Discipline of Psychiatry, Neurosciences Department, 'Carol Davila' University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Luana Geza
- Department of Psychiatry, 'Prof. Dr. Alexandru Obregia' Clinical Psychiatric Hospital, 041914 Bucharest, Romania.,Discipline of Psychiatry, Neurosciences Department, 'Carol Davila' University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Iulia Gabriela David
- Department of Analytical Chemistry, Faculty of Chemistry, University of Bucharest, 050663 Bucharest, Romania
| | - Dana Elena Popa
- Department of Analytical Chemistry, Faculty of Chemistry, University of Bucharest, 050663 Bucharest, Romania
| | - Mihaela Buleandra
- Department of Analytical Chemistry, Faculty of Chemistry, University of Bucharest, 050663 Bucharest, Romania
| | - Anton Alexandru Ciucu
- Department of Analytical Chemistry, Faculty of Chemistry, University of Bucharest, 050663 Bucharest, Romania
| | - Liana Dehelean
- Department of Neurosciences-Psychiatry, Centre for Cognitive Research in Neuropsychiatric Pathology, 'Victor Babes' University of Medicine and Pharmacy of Timisoara, 300041 Timisoara, Romania
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13
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Lech MA, Leśkiewicz M, Kamińska K, Rogóż Z, Lorenc-Koci E. Glutathione Deficiency during Early Postnatal Development Causes Schizophrenia-Like Symptoms and a Reduction in BDNF Levels in the Cortex and Hippocampus of Adult Sprague-Dawley Rats. Int J Mol Sci 2021; 22:ijms22126171. [PMID: 34201038 PMCID: PMC8229148 DOI: 10.3390/ijms22126171] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/11/2022] Open
Abstract
Growing body of evidence points to dysregulation of redox status in the brain as an important factor in the pathogenesis of schizophrenia. The aim of our study was to evaluate the effects of l-buthionine-(S,R)-sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor, and 1-[2-Bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine dihydrochloride (GBR 12909), a dopamine reuptake inhibitor, given alone or in combination, to Sprague–Dawley pups during early postnatal development (p5–p16), on the time course of the onset of schizophrenia-like behaviors, and on the expression of brain-derived neurotrophic factor (BDNF) mRNA and its protein in the prefrontal cortex (PFC) and hippocampus (HIP) during adulthood. BSO administered alone decreased the levels of BDNF mRNA and its protein both in the PFC and HIP. Treatment with the combination of BSO + GBR 12909 also decreased BDNF mRNA and its protein in the PFC, but in the HIP, only the level of BDNF protein was decreased. Schizophrenia-like behaviors in rats were assessed at three time points of adolescence (p30, p42–p44, p60–p62) and in early adulthood (p90–p92) using the social interaction test, novel object recognition test, and open field test. Social and cognitive deficits first appeared in the middle adolescence stage and continued to occur into adulthood, both in rats treated with BSO alone or with the BSO + GBR 12909 combination. Behavior corresponding to positive symptoms in humans occurred in the middle adolescence period, only in rats treated with BSO + GBR 12909. Only in the latter group, amphetamine exacerbated the existing positive symptoms in adulthood. Our data show that rats receiving the BSO + GBR 12909 combination in the early postnatal life reproduced virtually all symptoms observed in patients with schizophrenia and, therefore, can be considered a valuable neurodevelopmental model of this disease.
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Affiliation(s)
- Marta Anna Lech
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (M.A.L.); (K.K.); (Z.R.)
| | - Monika Leśkiewicz
- Department of Experimental Neuroendocrinology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland;
| | - Kinga Kamińska
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (M.A.L.); (K.K.); (Z.R.)
| | - Zofia Rogóż
- Department of Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland; (M.A.L.); (K.K.); (Z.R.)
| | - Elżbieta Lorenc-Koci
- Department of Neuro-Psychopharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, 31-343 Kraków, Poland
- Correspondence: ; Tel.: +48-126-623-272
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14
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Perez SM, Lodge DJ. Orexin Modulation of VTA Dopamine Neuron Activity: Relevance to Schizophrenia. Int J Neuropsychopharmacol 2021; 24:344-353. [PMID: 33587746 PMCID: PMC8059491 DOI: 10.1093/ijnp/pyaa080] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/13/2020] [Accepted: 10/26/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The hippocampus is a region consistently implicated in schizophrenia and has been advanced as a therapeutic target for positive, negative, and cognitive deficits associated with the disease. Recently, we reported that the paraventricular nucleus of the thalamus (PVT) works in concert with the ventral hippocampus to regulate dopamine system function; however, the PVT has yet to be investigated as target for the treatment of the disease. Given the dense expression of orexin receptors in the thalamus, we believe these to be a possible target for pharmacological regulation of PVT activity. METHODS Here we used the methylazoxymethanol acetate (MAM) rodent model, which displays pathological alterations consistent with schizophrenia to determine whether orexin receptor blockade can restore ventral tegmental area dopamine system function. We measured dopamine neuron population activity, using in vivo electrophysiology, following administration of the dual orexin antagonist, TCS 1102 (both intraperitoneal and intracranial into the PVT in MAM- and saline-treated rats), and orexin A and B peptides (intracranial into the PVT in naïve rats). RESULTS Aberrant dopamine system function in MAM-treated rats was normalized by the systemic administration of TCS 1102. To investigate the potential site of action, the orexin peptides A and B were administered directly into the PVT, where they significantly increased ventral tegmental area dopamine neuron population activity in control rats. In addition, the direct administration of TCS 1102 into the PVT reproduced the beneficial effects seen with the systemic administration in MAM-treated rats. CONCLUSION Taken together, these data suggest the orexin system may represent a novel site of therapeutic intervention for psychosis via an action in the PVT.
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Affiliation(s)
- Stephanie M Perez
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, TX, USA
| | - Daniel J Lodge
- Department of Pharmacology and Center for Biomedical Neuroscience, University of Texas Health Science Center, San Antonio, TX, USA
- South Texas Veterans Health Care System, Audie L. Murphy Division, USA
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15
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A systematic review of neuroimaging and acute cannabis exposure in age-of-risk for psychosis. Transl Psychiatry 2021; 11:217. [PMID: 33850098 PMCID: PMC8044224 DOI: 10.1038/s41398-021-01295-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/06/2021] [Accepted: 02/05/2021] [Indexed: 01/14/2023] Open
Abstract
Acute exposure to cannabis has been associated with an array of cognitive alterations, increased risk for neuropsychiatric illness, and other neuropsychiatric sequelae including the emergence of acute psychotic symptoms. However, the brain alterations associating cannabis use and these behavioral and clinical phenotypes remains disputed. To this end, neuroimaging can be a powerful technique to non-invasively study the impact of cannabis exposure on brain structure and function in both humans and animal models. While chronic exposure studies provide insight into how use may be related to long-term outcomes, acute exposure may reveal interesting information regarding the immediate impact of use and abuse on brain circuits. Understanding these alterations could reveal the connection with symptom dimensions in neuropsychiatric disorders and, more specifically with psychosis. The purpose of the present review is to: 1) provide an update on the findings of pharmacological neuroimaging studies examining the effects of administered cannabinoids and 2) focus the discussion on studies that examine the sensitive window for the emergence of psychosis. Current literature indicates that cannabis exposure has varied effects on the brain, with the principal compounds in cannabis (delta-9-tetrahydrocannabinol and cannabidiol) altering activity across different brain regions. Importantly, we also discovered critical gaps in the literature, particularly regarding sex-dependent responses and long-term effects of chronic exposure. Certain networks often characterized as dysregulated in psychosis, like the default mode network and limbic system, were also impacted by THC exposure, identifying areas of particular interest for future work investigating the potential relationship between the two.
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16
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Granger KT, Ferrar J, Caswell S, Haselgrove M, Moran PM, Attwood A, Barnett JH. Effects of 7.5% Carbon Dioxide and Nicotine Administration on Latent Inhibition. Front Psychiatry 2021; 12:582745. [PMID: 33935819 PMCID: PMC8085318 DOI: 10.3389/fpsyt.2021.582745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 02/05/2021] [Indexed: 12/01/2022] Open
Abstract
Stratified medicine approaches have potential to improve the efficacy of drug development for schizophrenia and other psychiatric conditions, as they have for oncology. Latent inhibition is a candidate biomarker as it demonstrates differential sensitivity to key symptoms and neurobiological abnormalities associated with schizophrenia. The aims of this research were to evaluate whether a novel latent inhibition task that is not confounded by alternative learning effects such as learned irrelevance, is sensitive to (1) an in-direct model relevant to psychosis [using 7.5% carbon dioxide (CO2) inhalations to induce dopamine release via somatic anxiety] and (2) a pro-cognitive pharmacological manipulation (via nicotine administration) for the treatment of cognitive impairment associated with schizophrenia. Experiment 1 used a 7.5% CO2 challenge as a model of anxiety-induced dopamine release to evaluate the sensitivity of latent inhibition during CO2 gas inhalation, compared to the inhalation of medical air. Experiment 2 examined the effect of 2 mg nicotine administration vs. placebo on latent inhibition to evaluate its sensitivity to a potential pro-cognitive drug treatment. Inhalation of 7.5% CO2 raised self-report and physiological measures of anxiety and impaired latent inhibition, relative to a medical air control; whereas administration of 2 mg nicotine, demonstrated increased latent inhibition relative to placebo control. Here, two complementary experimental studies suggest latent inhibition is modified by manipulations that are relevant to the detection and treatment of schizophrenia. These results suggest that this latent inhibition task merits further investigation in the context of neurobiological sub-groups suitable for novel treatment strategies.
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Affiliation(s)
- Kiri T Granger
- Cambridge Cognition, Cambridge, United Kingdom.,School of Psychology, University of Nottingham, Nottingham, United Kingdom.,Monument Therapeutics, Cambridge, United Kingdom
| | - Jennifer Ferrar
- Cambridge Cognition, Cambridge, United Kingdom.,Alcohol & Tobacco Research Group, University of Bristol, Bristol, United Kingdom
| | - Sheryl Caswell
- Cambridge Cognition, Cambridge, United Kingdom.,Monument Therapeutics, Cambridge, United Kingdom
| | - Mark Haselgrove
- School of Psychology, University of Nottingham, Nottingham, United Kingdom
| | - Paula M Moran
- School of Psychology, University of Nottingham, Nottingham, United Kingdom
| | - Angela Attwood
- Alcohol & Tobacco Research Group, University of Bristol, Bristol, United Kingdom
| | - Jennifer H Barnett
- Cambridge Cognition, Cambridge, United Kingdom.,Monument Therapeutics, Cambridge, United Kingdom.,Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
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17
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Sonnenschein SF, Grace AA. Emerging therapeutic targets for schizophrenia: a framework for novel treatment strategies for psychosis. Expert Opin Ther Targets 2021; 25:15-26. [PMID: 33170748 PMCID: PMC7855878 DOI: 10.1080/14728222.2021.1849144] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 11/05/2020] [Indexed: 01/10/2023]
Abstract
Introduction: Antipsychotic drugs are central to the treatment of schizophrenia, but their limitations necessitate improved treatment strategies. Multiple lines of research have implicated glutamatergic dysfunction in the hippocampus as an early source of pathophysiology in schizophrenia. Novel compounds have been designed to treat glutamatergic dysfunction, but they have produced inconsistent results in clinical trials. Areas covered: This review discusses how the hippocampus is thought to drive psychotic symptoms through its influence on the dopamine system. It offers the reader an evaluation of proposed treatment strategies including direct modulation of GABA or glutamate neurotransmission or reducing the deleterious impact of stress on circuit development. Finally, we offer a perspective on aspects of future research that will advance our knowledge and may create new therapeutic opportunities. PubMed was searched for relevant literature between 2010 and 2020 and related studies. Expert opinion: Targeting aberrant excitatory-inhibitory neurotransmission in the hippocampus and its related circuits has the potential to alleviate symptoms and reduce the risk of transition to psychosis if implemented as an early intervention. Longitudinal multimodal brain imaging combined with mechanistic theories generated from animal models can be used to better understand the progression of hippocampal-dopamine circuit dysfunction and heterogeneity in treatment response.
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Affiliation(s)
| | - Anthony A. Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
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18
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Kalyoncu A, Gonul AS. The Emerging Role of SPECT Functional Neuroimaging in Schizophrenia and Depression. Front Psychiatry 2021; 12:716600. [PMID: 34975556 PMCID: PMC8714796 DOI: 10.3389/fpsyt.2021.716600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
Over the last three decades, the brain's functional and structural imaging has become more prevalent in psychiatric research and clinical application. A substantial amount of psychiatric research is based on neuroimaging studies that aim to illuminate neural mechanisms underlying psychiatric disorders. Single-photon emission computed tomography (SPECT) is one of those developing brain imaging techniques among various neuroimaging technologies. Compared to PET, SPECT imaging is easy, less expensive, and practical for radioligand use. Current technologies increased the spatial accuracy of SPECT findings by combining the functional SPECT images with CT images. The radioligands bind to receptors such as 5-hydroxytryptamine 2A, and dopamine transporters can help us comprehend neural mechanisms of psychiatric disorders based on neurochemicals. This mini-review focuses on the SPECT-based neuroimaging approach to psychiatric disorders such as schizophrenia and major depressive disorder (MDD). Research-based SPECT findings of psychiatric disorders indicate that there are notable changes in biochemical components in certain disorders. Even though many studies support that SPECT can be used in psychiatric clinical practice, we still only use subjective diagnostic criteria such as the Diagnostic Statistical Manual of Mental Disorders (DSM-5). Glimpsing into the brain's biochemical world via SPECT in psychiatric disorders provides more information about the pathophysiology and future implication of neuroimaging techniques.
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Affiliation(s)
- Anil Kalyoncu
- Department of Psychiatry, Ege University School of Medicine, Izmir, Turkey
| | - Ali Saffet Gonul
- Department of Psychiatry, Ege University School of Medicine, Izmir, Turkey
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19
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Sonnenschein SF, Gomes FV, Grace AA. Dysregulation of Midbrain Dopamine System and the Pathophysiology of Schizophrenia. Front Psychiatry 2020; 11:613. [PMID: 32719622 PMCID: PMC7350524 DOI: 10.3389/fpsyt.2020.00613] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 06/12/2020] [Indexed: 11/25/2022] Open
Abstract
Dysregulation of the dopamine system is central to many models of the pathophysiology of psychosis in schizophrenia. However, emerging evidence suggests that this dysregulation is driven by the disruption of upstream circuits that provide afferent control of midbrain dopamine neurons. Furthermore, stress can profoundly disrupt this regulatory circuit, particularly when it is presented at critical vulnerable prepubertal time points. This review will discuss the dopamine system and the circuits that regulate it, focusing on the hippocampus, medial prefrontal cortex, thalamic nuclei, and medial septum, and the impact of stress. A greater understanding of the regulation of the dopamine system and its disruption in schizophrenia may provide a more complete neurobiological framework to interpret clinical findings and develop novel treatments.
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Affiliation(s)
- Susan F Sonnenschein
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Felipe V Gomes
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Anthony A Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
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20
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The Effect of Chronic Methamphetamine Treatment on Schizophrenia Endophenotypes in Heterozygous Reelin Mice: Implications for Schizophrenia. Biomolecules 2020; 10:biom10060940. [PMID: 32580454 PMCID: PMC7355789 DOI: 10.3390/biom10060940] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/12/2020] [Accepted: 06/19/2020] [Indexed: 01/29/2023] Open
Abstract
Reelin has been implicated in the development of schizophrenia but the mechanisms involved in this interaction remain unclear. Chronic methamphetamine (Meth) use may cause dopaminergic sensitisation and psychosis and has been proposed to affect brain dopamine systems similarly to changes seen in schizophrenia. We compared the long-term effect of chronic Meth treatment between heterozygous reelin mice (HRM) and wildtype controls (WT) with the aim of better understanding the role of reelin in schizophrenia. Meth pretreatment induced sensitisation to the effect of an acute Meth challenge on locomotor activity, but it had no effect on baseline PPI or sociability and social preference. In all behavioural models, HRM did not significantly differ from WT at baseline, except spontaneous exploratory locomotor activity which was higher in HRM than WT, and sociability which was enhanced in HRM. Locomotor hyperactivity sensitisation was not significantly different between HRM and WT. Chronic Meth treatment reduced spontaneous locomotor activity to the level of WT. No deficits in PPI or social behaviour were induced by chronic Meth pretreatment in either strain. In conclusion, these data do not support a role of reelin in schizophrenia, at least not in HRM and in the methamphetamine sensitisation model.
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21
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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. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND 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] [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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22
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Howes OD, Bonoldi I, McCutcheon RA, Azis M, Antoniades M, Bossong M, Modinos G, Perez J, Stone JM, Santangelo B, Veronese M, Grace A, Allen P, McGuire PK. Glutamatergic and dopaminergic function and the relationship to outcome in people at clinical high risk of psychosis: a multi-modal PET-magnetic resonance brain imaging study. Neuropsychopharmacology 2020; 45:641-648. [PMID: 31618752 PMCID: PMC7021794 DOI: 10.1038/s41386-019-0541-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 12/11/2022]
Abstract
Preclinical models of psychosis propose that hippocampal glutamatergic neuron hyperactivity drives increased striatal dopaminergic activity, which underlies the development of psychotic symptoms. The aim of this study was to examine the relationship between hippocampal glutamate and subcortical dopaminergic function in people at clinical high risk for psychosis, and to assess the association with the development of psychotic symptoms. 1H-MRS was used to measure hippocampal glutamate concentrations, and 18F-DOPA PET was used to measure dopamine synthesis capacity in 70 subjects (51 people at clinical high risk for psychosis and 19 healthy controls). Clinical assessments were undertaken at baseline and follow-up (median 15 months). Striatal dopamine synthesis capacity predicted the worsening of psychotic symptoms at follow-up (r = 0.35; p < 0.05), but not transition to a psychotic disorder (p = 0.22), and was not significantly related to hippocampal glutamate concentration (p = 0.13). There were no differences in either glutamate (p = 0.5) or dopamine (p = 0.5) measures in the total patient group relative to controls. Striatal dopamine synthesis capacity at presentation predicts the subsequent worsening of sub-clinical total and psychotic symptoms, consistent with a role for dopamine in the development of psychotic symptoms, but is not strongly linked to hippocampal glutamate concentrations.
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Affiliation(s)
- Oliver D Howes
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK.
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
- TREAT Service, South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, SE5 8AZ, UK.
| | - Ilaria Bonoldi
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
- TREAT Service, South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, SE5 8AZ, UK
| | - Robert A McCutcheon
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK.
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, Du Cane Road, London, W12 0NN, UK.
| | - Matilda Azis
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Mathilde Antoniades
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Matthijs Bossong
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
- Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Gemma Modinos
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Jesus Perez
- Cambridge Early Onset service, Cambridgeshire and Peterborough Mental Health Partnership National Health Service Trust, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - James M Stone
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Barbara Santangelo
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Mattia Veronese
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
| | - Anthony Grace
- Department of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Paul Allen
- Department of Psychology, University of Roehampton, London, UK
| | - Philip K McGuire
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, Camberwell, London, SE5 8AF, UK
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McCutcheon RA, Krystal JH, Howes OD. Dopamine and glutamate in schizophrenia: biology, symptoms and treatment. World Psychiatry 2020; 19:15-33. [PMID: 31922684 PMCID: PMC6953551 DOI: 10.1002/wps.20693] [Citation(s) in RCA: 252] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Glutamate and dopamine systems play distinct roles in terms of neuronal signalling, yet both have been proposed to contribute significantly to the pathophysiology of schizophrenia. In this paper we assess research that has implicated both systems in the aetiology of this disorder. We examine evidence from post-mortem, preclinical, pharmacological and in vivo neuroimaging studies. Pharmacological and preclinical studies implicate both systems, and in vivo imaging of the dopamine system has consistently identified elevated striatal dopamine synthesis and release capacity in schizophrenia. Imaging of the glutamate system and other aspects of research on the dopamine system have produced less consistent findings, potentially due to methodological limitations and the heterogeneity of the disorder. Converging evidence indicates that genetic and environmental risk factors for schizophrenia underlie disruption of glutamatergic and dopaminergic function. However, while genetic influences may directly underlie glutamatergic dysfunction, few genetic risk variants directly implicate the dopamine system, indicating that aberrant dopamine signalling is likely to be predominantly due to other factors. We discuss the neural circuits through which the two systems interact, and how their disruption may cause psychotic symptoms. We also discuss mechanisms through which existing treatments operate, and how recent research has highlighted opportunities for the development of novel pharmacological therapies. Finally, we consider outstanding questions for the field, including what remains unknown regarding the nature of glutamate and dopamine function in schizophrenia, and what needs to be achieved to make progress in developing new treatments.
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Affiliation(s)
- Robert A McCutcheon
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
- South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, UK
| | - John H Krystal
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- VA National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Oliver D Howes
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
- South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, UK
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24
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Weidenauer A, Bauer M, Sauerzopf U, Bartova L, Nics L, Pfaff S, Philippe C, Berroterán-Infante N, Pichler V, Meyer BM, Rabl U, Sezen P, Cumming P, Stimpfl T, Sitte HH, Lanzenberger R, Mossaheb N, Zimprich A, Rusjan P, Dorffner G, Mitterhauser M, Hacker M, Pezawas L, Kasper S, Wadsak W, Praschak-Rieder N, Willeit M. On the relationship of first-episode psychosis to the amphetamine-sensitized state: a dopamine D 2/3 receptor agonist radioligand study. Transl Psychiatry 2020; 10:2. [PMID: 32066718 PMCID: PMC7026156 DOI: 10.1038/s41398-019-0681-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 10/01/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
Schizophrenia is characterized by increased behavioral and neurochemical responses to dopamine-releasing drugs. This prompted the hypothesis of psychosis as a state of "endogenous" sensitization of the dopamine system although the exact basis of dopaminergic disturbances and the possible role of prefrontal cortical regulation have remained uncertain. To show that patients with first-episode psychosis release more dopamine upon amphetamine-stimulation than healthy volunteers, and to reveal for the first time that prospective sensitization induced by repeated amphetamine exposure increases dopamine-release in stimulant-naïve healthy volunteers to levels observed in patients, we collected data on amphetamine-induced dopamine release using the dopamine D2/3 receptor agonist radioligand [11C]-(+)-PHNO and positron emission tomography. Healthy volunteers (n = 28, 14 female) underwent a baseline and then a post-amphetamine scan before and after a mildly sensitizing regimen of repeated oral amphetamine. Unmedicated patients with first-episode psychosis (n = 21; 6 female) underwent a single pair of baseline and then post-amphetamine scans. Furthermore, T1 weighted magnetic resonance imaging of the prefrontal cortex was performed. Patients with first-episode psychosis showed larger release of dopamine compared to healthy volunteers. After sensitization of healthy volunteers their dopamine release was significantly amplified and no longer different from that seen in patients. Healthy volunteers showed a negative correlation between prefrontal cortical volume and dopamine release. There was no such relationship after sensitization or in patients. Our data in patients with untreated first-episode psychosis confirm the "endogenous sensitization" hypothesis and support the notion of impaired prefrontal control of the dopamine system in schizophrenia.
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Affiliation(s)
- Ana Weidenauer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Martin Bauer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Ulrich Sauerzopf
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Lucie Bartova
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Lukas Nics
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Sarah Pfaff
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Cecile Philippe
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Neydher Berroterán-Infante
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Verena Pichler
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Bernhard M Meyer
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Ulrich Rabl
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Patrick Sezen
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Paul Cumming
- School of Psychology and Counseling and IHBI, Queensland University of Technology, Brisbane, Australia
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Thomas Stimpfl
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Harald H Sitte
- Institute of Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Nilufar Mossaheb
- Department of Psychiatry and Psychotherapy, Division of Social Psychiatry, Medical University of Vienna, Vienna, Austria
| | | | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Canada
| | - Georg Dorffner
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Markus Mitterhauser
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute Applied Diagnostics, Vienna, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Lukas Pezawas
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Siegfried Kasper
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Wolfgang Wadsak
- Department of Biomedical Imaging and Image Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Nicole Praschak-Rieder
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Matthäus Willeit
- Department of Psychiatry and Psychotherapy, Division of General Psychiatry, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
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25
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Aguilar-Valles A, Rodrigue B, Matta-Camacho E. Maternal Immune Activation and the Development of Dopaminergic Neurotransmission of the Offspring: Relevance for Schizophrenia and Other Psychoses. Front Psychiatry 2020; 11:852. [PMID: 33061910 PMCID: PMC7475700 DOI: 10.3389/fpsyt.2020.00852] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/04/2020] [Indexed: 12/21/2022] Open
Abstract
Prenatal infections have been linked to the development of schizophrenia (SCZ) and other neurodevelopmental disorders in the offspring, and work in animal models indicates that this is to occur through the maternal inflammatory response triggered by infection. Several studies in animal models demonstrated that acute inflammatory episodes are sufficient to trigger brain alterations in the adult offspring, especially in the mesolimbic dopamine (DA) system, involved in the pathophysiology of SCZ and other disorders involving psychosis. In the current review, we synthesize the literature on the clinical studies implicating prenatal infectious events in the development of SCZ. Then, we summarize evidence from animal models of maternal immune activation (MIA) and the behavioral and molecular alterations relevant for the function of the DAergic system. Furthermore, we discuss the evidence supporting the involvement of maternal cytokines, such as interleukin 6 (IL-6) and leptin (a hormone with effects on inflammation) in mediating the effects of MIA on the fetal brain, leading to the long-lasting effects on the offspring. In particular, IL-6 has been involved in mediating the effects of MIA animal models in the offspring through actions on the placenta, induction of IL-17a, or triggering the decrease in non-heme iron (hypoferremia). Maternal infection is very likely interacting with additional genetic and environmental risk factors in the development of SCZ; systematically investigating how these interactions produce specific phenotypes is the next step in understanding the etiology of complex psychiatric disorders.
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Affiliation(s)
| | - Brandon Rodrigue
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
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26
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de Bartolomeis A, Manchia M, Marmo F, Vellucci L, Iasevoli F, Barone A. Glycine Signaling in the Framework of Dopamine-Glutamate Interaction and Postsynaptic Density. Implications for Treatment-Resistant Schizophrenia. Front Psychiatry 2020; 11:369. [PMID: 32477178 PMCID: PMC7240307 DOI: 10.3389/fpsyt.2020.00369] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/14/2020] [Indexed: 12/14/2022] Open
Abstract
Treatment-resistant schizophrenia (TRS) or suboptimal response to antipsychotics affects almost 30% of schizophrenia (SCZ) patients, and it is a relevant clinical issue with significant impact on the functional outcome and on the global burden of disease. Among putative novel treatments, glycine-centered therapeutics (i.e. sarcosine, glycine itself, D-Serine, and bitopertin) have been proposed, based on a strong preclinical rationale with, however, mixed clinical results. Therefore, a better appraisal of glycine interaction with the other major players of SCZ pathophysiology and specifically in the framework of dopamine - glutamate interactions is warranted. New methodological approaches at cutting edge of technology and drug discovery have been applied to study the role of glycine in glutamate signaling, both at presynaptic and post-synaptic level and have been instrumental for unveiling the role of glycine in dopamine-glutamate interaction. Glycine is a non-essential amino acid that plays a critical role in both inhibitory and excitatory neurotransmission. In caudal areas of central nervous system (CNS), such as spinal cord and brainstem, glycine acts as a powerful inhibitory neurotransmitter through binding to its receptor, i.e. the Glycine Receptor (GlyR). However, glycine also works as a co-agonist of the N-Methyl-D-Aspartate receptor (NMDAR) in excitatory glutamatergic neurotransmission. Glycine concentration in the synaptic cleft is finely tuned by glycine transporters, i.e. GlyT1 and GlyT2, that regulate the neurotransmitter's reuptake, with the first considered a highly potential target for psychosis therapy. Reciprocal regulation of dopamine and glycine in forebrain, glycine modulation of glutamate, glycine signaling interaction with postsynaptic density proteins at glutamatergic synapse, and human genetics of glycinergic pathways in SCZ are tackled in order to highlight the exploitation of this neurotransmitters and related molecules in SCZ and TRS.
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Affiliation(s)
- Andrea de Bartolomeis
- Laboratory of Molecular Psychiatry and Translational Psychiatry, Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Science and Odontostomatology, University School of Medicine of Napoli Federico II, Naples, Italy
| | - Mirko Manchia
- Section of Psychiatry, Department of Medical Science and Public Health, University of Cagliari, Cagliari, Italy.,Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
| | - Federica Marmo
- Laboratory of Molecular Psychiatry and Translational Psychiatry, Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Science and Odontostomatology, University School of Medicine of Napoli Federico II, Naples, Italy
| | - Licia Vellucci
- Laboratory of Molecular Psychiatry and Translational Psychiatry, Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Science and Odontostomatology, University School of Medicine of Napoli Federico II, Naples, Italy
| | - Felice Iasevoli
- Laboratory of Molecular Psychiatry and Translational Psychiatry, Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Science and Odontostomatology, University School of Medicine of Napoli Federico II, Naples, Italy
| | - Annarita Barone
- Laboratory of Molecular Psychiatry and Translational Psychiatry, Unit of Treatment Resistant Psychosis, Section of Psychiatry, Department of Neuroscience, Reproductive Science and Odontostomatology, University School of Medicine of Napoli Federico II, Naples, Italy
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27
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Ellis JK, Walker EF, Goldsmith DR. Selective Review of Neuroimaging Findings in Youth at Clinical High Risk for Psychosis: On the Path to Biomarkers for Conversion. Front Psychiatry 2020; 11:567534. [PMID: 33173516 PMCID: PMC7538833 DOI: 10.3389/fpsyt.2020.567534] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/31/2020] [Indexed: 12/19/2022] Open
Abstract
First episode psychosis (FEP), and subsequent diagnosis of schizophrenia or schizoaffective disorder, predominantly occurs during late adolescence, is accompanied by a significant decline in function and represents a traumatic experience for patients and families alike. Prior to first episode psychosis, most patients experience a prodromal period of 1-2 years, during which symptoms first appear and then progress. During that time period, subjects are referred to as being at Clinical High Risk (CHR), as a prodromal period can only be designated in hindsight in those who convert. The clinical high-risk period represents a critical window during which interventions may be targeted to slow or prevent conversion to psychosis. However, only one third of subjects at clinical high risk will convert to psychosis and receive a formal diagnosis of a primary psychotic disorder. Therefore, in order for targeted interventions to be developed and applied, predicting who among this population will convert is of critical importance. To date, a variety of neuroimaging modalities have identified numerous differences between CHR subjects and healthy controls. However, complicating attempts at predicting conversion are increasingly recognized co-morbidities, such as major depressive disorder, in a significant number of CHR subjects. The result of this is that phenotypes discovered between CHR subjects and healthy controls are likely non-specific to psychosis and generalized for major mental illness. In this paper, we selectively review evidence for neuroimaging phenotypes in CHR subjects who later converted to psychosis. We then evaluate the recent landscape of machine learning as it relates to neuroimaging phenotypes in predicting conversion to psychosis.
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Affiliation(s)
- Justin K Ellis
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States
| | - Elaine F Walker
- Department of Psychology, Emory University, Atlanta, GA, United States
| | - David R Goldsmith
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States
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28
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Altered levels of dopamine transporter in the frontal pole and dorsal striatum in schizophrenia. NPJ SCHIZOPHRENIA 2019; 5:20. [PMID: 31792225 PMCID: PMC6888821 DOI: 10.1038/s41537-019-0087-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 09/18/2019] [Indexed: 12/12/2022]
Abstract
The dopamine hypothesis proposes that there is a hypodopaminergic state in the prefrontal cortex and a hyperdopaminergic state in the striatum of patients with schizophrenia. Evidence suggests the hyperdopaminergic state in the striatum is due to synaptic dopamine elevation, particularly in the dorsal striatum. However, the molecular mechanisms causing disrupted dopaminergic function in schizophrenia remains unclear. We postulated that the dopamine transporter (DAT), which regulates intra-synaptic dopamine concentrations by transporting dopamine from the synaptic cleft into the pre-synaptic neuron, could be involved in dopaminergic dysfunction in schizophrenia. Therefore, we measured levels of DAT in the cortex and striatum from patients with schizophrenia and controls using postmortem human brain tissue. Levels of desmethylimipramine-insensitive mazindol-sensitive [3H]mazindol binding to DAT were measured using in situ radioligand binding and autoradiography in gray matter from Brodmann’s area (BA) 10, BA 17, the dorsal striatum, and nucleus accumbens from 15 patients with schizophrenia and 15 controls. Levels of desmethylimipramine-insensitive mazindol-sensitive [3H]mazindol binding were significantly higher in BA 10 from patients with schizophrenia (p = 0.004) and significantly lower in the dorsal striatum (dorsal putamen p = 0.005; dorsal caudate p = 0.007) from those with the disorder. There were no differences in levels of desmethylimipramine-insensitive [3H]mazindol binding in BA 17 or nucleus accumbens. These data raise the possibility that high levels of DAT in BA 10 could be contributing to lower synaptic cortical dopamine, whereas lower levels of DAT could be contributing to a hyperdopaminergic state in the dorsal striatum.
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29
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The relationship between childhood trauma, dopamine release and dexamphetamine-induced positive psychotic symptoms: a [ 11C]-(+)-PHNO PET study. Transl Psychiatry 2019; 9:287. [PMID: 31712556 PMCID: PMC6848217 DOI: 10.1038/s41398-019-0627-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 09/17/2019] [Accepted: 10/20/2019] [Indexed: 02/08/2023] Open
Abstract
Childhood trauma is a risk factor for psychosis. Amphetamine increases synaptic striatal dopamine levels and can induce positive psychotic symptoms in healthy individuals and patients with schizophrenia. Socio-developmental hypotheses of psychosis propose that childhood trauma and other environmental risk factors sensitize the dopamine system to increase the risk of psychotic symptoms, but this remains to be tested in humans. We used [11C]-(+)-PHNO positron emission tomography to measure striatal dopamine-2/3 receptor (D2/3R) availability and ventral striatal dexamphetamine-induced dopamine release in healthy participants (n = 24). The relationships between dexamphetamine-induced dopamine release, dexamphetamine-induced positive psychotic symptoms using the Positive and Negative Syndrome Scale (PANSS), and childhood trauma using the Childhood Trauma Questionnaire (CTQ) were assessed using linear regression and mediation analyses, with childhood trauma as the independent variable, dexamphetamine-induced dopamine release as the mediator variable, and dexamphetamine-induced symptoms as the dependent variable. There was a significant interaction between childhood trauma and ventral striatal dopamine release in predicting dexamphetamine-induced positive psychotic symptoms (standardized β = 1.83, p = 0.003), but a mediation analysis was not significant (standardized β = -0.18, p = 0.158). There were no significant effects of dopamine release and childhood trauma on change in negative (p = 0.280) or general PANSS symptoms (p = 0.061), and there was no relationship between ventral striatal baseline D2/3R availability and positive symptoms (p = 0.368). This indicates childhood trauma and dopamine release interact to influence the induction of positive psychotic symptoms. This is not consistent with a simple sensitization hypothesis, but suggests that childhood trauma moderates the cognitive response to dopamine release to make psychotic experiences more likely.
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Kynurenines and the Endocannabinoid System in Schizophrenia: Common Points and Potential Interactions. Molecules 2019; 24:molecules24203709. [PMID: 31619006 PMCID: PMC6832375 DOI: 10.3390/molecules24203709] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/15/2022] Open
Abstract
Schizophrenia, which affects around 1% of the world’s population, has been described as a complex set of symptoms triggered by multiple factors. However, the exact background mechanisms remain to be explored, whereas therapeutic agents with excellent effectivity and safety profiles have yet to be developed. Kynurenines and the endocannabinoid system (ECS) play significant roles in both the development and manifestation of schizophrenia, which have been extensively studied and reviewed previously. Accordingly, kynurenines and the ECS share multiple features and mechanisms in schizophrenia, which have yet to be reviewed. Thus, the present study focuses on the main common points and potential interactions between kynurenines and the ECS in schizophrenia, which include (i) the regulation of glutamatergic/dopaminergic/γ-aminobutyric acidergic neurotransmission, (ii) their presence in astrocytes, and (iii) their role in inflammatory mechanisms. Additionally, promising pharmaceutical approaches involving the kynurenine pathway and the ECS will be reviewed herein.
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Banasikowski TJ, Hawken ER. The Bed Nucleus of the Stria Terminalis, Homeostatic Satiety, and Compulsions: What Can We Learn From Polydipsia? Front Behav Neurosci 2019; 13:170. [PMID: 31417376 PMCID: PMC6686835 DOI: 10.3389/fnbeh.2019.00170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 07/12/2019] [Indexed: 12/28/2022] Open
Abstract
A compulsive phenotype characterizes several neuropsychiatric illnesses - including but not limited to - schizophrenia and obsessive compulsive disorder. Because of its perceived etiological heterogeneity, it is challenging to disentangle the specific neurophysiology that precipitates compulsive behaving. Using polydipsia (or non-regulatory water drinking), we describe candidate neural substrates of compulsivity. We further postulate that aberrant neuroplasticity within cortically projecting structures [i.e., the bed nucleus of the stria terminalis (BNST)] and circuits that encode homeostatic emotions (thirst, hunger, satiety, etc.) underlie compulsive drinking. By transducing an inaccurate signal that fails to represent true homeostatic state, cortical structures cannot select appropriate and adaptive actions. Additionally, augmented dopamine (DA) reactivity in striatal projections to and from the frontal cortex contribute to aberrant homeostatic signal propagation that ultimately biases cortex-dependent behavioral selection. Responding becomes rigid and corresponds with both erroneous, inflexible encoding in both bottom-up structures and in top-down pathways. How aberrant neuroplasticity in circuits that encode homeostatic emotion result in the genesis and maintenance of compulsive behaviors needs further investigation.
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Affiliation(s)
- Tomek J Banasikowski
- Department of Psychiatry, Queen's University, Kingston, ON, Canada.,Providence Care Hospital, Kingston, ON, Canada
| | - Emily R Hawken
- Department of Psychiatry, Queen's University, Kingston, ON, Canada.,Providence Care Hospital, Kingston, ON, Canada
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32
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Vicario-Feliciano R, Wigton RL, White TP, Shergill SS, Averbeck BB. Dopamine manipulations drive changes in information sampling in healthy volunteers. J Psychopharmacol 2019; 33:670-677. [PMID: 30644326 PMCID: PMC6996051 DOI: 10.1177/0269881118822080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Information sampling is the cognitive process of accumulating information before committing to a decision. Patients across numerous disorders show decreased information sampling relative to controls. AIMS Here, we used the Beads and the Best Choice Tasks to study the role of dopamine signaling in information sampling. METHODS Participants were given placebo, amisulpride, or ropinirole in each session, in a double-blind cross-over design. RESULTS We found that ropinirole (agonist) increased the number of beads drawn in the Beads Task specifically when participants faced a loss, and decreased the rank of the chosen option in the Best Choice Task. CONCLUSIONS These effects are likely driven by a combination of effects at presynaptic D2 receptors, which affect dopamine release, and post-synaptic D2 receptors. Increased D2 relative to D1 receptor activation in the striatum leads to increased sampling in the loss condition in the Beads Task. It also leads to choice of a poorer ranked option in the Best Choice Task. Decreased D2 relative to D1 receptor activation leads to decreased sampling in the Beads Task in the loss condition.
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Affiliation(s)
| | - Rebekah L Wigton
- Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Thomas P White
- Institute of Psychiatry, Psychology and Neuroscience, London, UK,School of Psychology, University of Birmingham, Birmingham, UK
| | - Sukhi S Shergill
- Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Bruno B Averbeck
- Laboratory of Neuropsychology, National Institutes of Health, MD, USA
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33
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Insights on current and novel antipsychotic mechanisms from the MAM model of schizophrenia. Neuropharmacology 2019; 163:107632. [PMID: 31077730 DOI: 10.1016/j.neuropharm.2019.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 04/25/2019] [Accepted: 05/07/2019] [Indexed: 12/18/2022]
Abstract
Current antipsychotic drugs (APDs) act on D2 receptors, and preclinical studies demonstrate that repeated D2 antagonist administration downregulates spontaneously active DA neurons by producing overexcitation-induced inactivation of firing (depolarization block). Animal models of schizophrenia based on the gestational MAM administration produces offspring with adult phenotypes consistent with schizophrenia, including ventral hippocampal hyperactivity and a DA neuron overactivity. The MAM model reveals that APDs act differently in a hyperdopamineregic system compared to a normal one, including rapid onset of depolarization block in response to acute D2 antagonist administration and downregulation of DA neuron population activity following acute and repeated D2 partial agonist administration, none of which are observed in normal rats. Novel target compounds have been developed based on the theory that glutamatergic dysfunction is central to schizophrenia pathology. Despite showing promise in preclinical research, none of the novel drugs succeeded in clinical trials. However, preclinical research is generally performed in normal, drug-naïve rats, whereas models with disease-relevant pathology and prior APD exposure may improve the predictive validity of preclinical research. Indeed, in MAM rats, chronic D2 antagonist treatment leads to persistent DA supersensitivity that interferes with the response to drugs that target upstream pathology. Moreover, MAM rats revealed that the peri-pubertal period is a stress-sensitive window that can be targeted to prevent the development of MAM pathology in adulthood. Neurodevelopmental models, such as the MAM model, can thus be used to test potential pharmacotherapies that may be able to treat schizophrenia in early stages of the disease. This article is part of the issue entitled 'Special Issue on Antipsychotics'.
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34
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Petty A, Cui X, Tesiram Y, Kirik D, Howes O, Eyles D. Enhanced Dopamine in Prodromal Schizophrenia (EDiPS): a new animal model of relevance to schizophrenia. NPJ SCHIZOPHRENIA 2019; 5:6. [PMID: 30926827 PMCID: PMC6441087 DOI: 10.1038/s41537-019-0074-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 03/12/2019] [Indexed: 12/13/2022]
Abstract
One of the most robust neurochemical abnormalities reported in patients living with schizophrenia is an increase in dopamine (DA) synthesis and release in the dorsal striatum (DS). Importantly, it appears that this increase progresses as a patient transitions from a prodromal stage to the clinical diagnosis of schizophrenia. Here we have recreated this pathophysiology in an animal model by increasing the capacity for DA synthesis preferentially within the DS. To achieve this we administer a genetic construct containing the rate-limiting enzymes in DA synthesis—tyrosine hydroxylase (TH), and GTP cyclohydrolase 1 (GCH1) (packaged within an adeno-associated virus)—into the substantia nigra pars compacta (SNpc) of adolescent animals. We refer to this model as “Enhanced Dopamine in Prodromal Schizophrenia” (EDiPS). We first confirmed that the TH enzyme is preferentially increased in the DS. As adults, EDiPS animals release significantly more DA in the DS following a low dose of amphetamine (AMPH), have increased AMPH-induced hyperlocomotion and show deficits in pre-pulse inhibition (PPI). The glutamatergic response to AMPH is also altered, again in the DS. EDiPS represents an ideal experimental platform to (a) understand how a preferential increase in DA synthesis capacity in the DS relates to “positive” symptoms in schizophrenia; (b) understand how manipulation of DS DA may influence other neurotransmitter systems shown to be altered in patients with schizophrenia; (c) allow researchers to follow an “at risk”-like disease course from adolescence to adulthood; and (d) ultimately allow trials of putative prophylactic agents to prevent disease onset in vulnerable populations.
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Affiliation(s)
- Alice Petty
- Queensland Brain Institute, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Xiaoying Cui
- Queensland Brain Institute, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Yasvir Tesiram
- Centre for Advanced Imaging, University of Queensland, QLD, Brisbane, 4072, Australia
| | - Deniz Kirik
- BRAINS Unit, Department of Experimental Medical Science, Lund University, 22184, Lund, Sweden
| | - Oliver Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,MRS London Institute of Medical Sciences, Hammersmith Hospital, London, UK.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
| | - Darryl Eyles
- Queensland Brain Institute, University of Queensland, Brisbane, QLD, 4072, Australia. .,Queensland Centre for Mental Health Research, Wacol, QLD, 4076, Australia.
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Amato D, Kruyer A, Samaha AN, Heinz A. Hypofunctional Dopamine Uptake and Antipsychotic Treatment-Resistant Schizophrenia. Front Psychiatry 2019; 10:314. [PMID: 31214054 PMCID: PMC6557273 DOI: 10.3389/fpsyt.2019.00314] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/23/2019] [Indexed: 01/07/2023] Open
Abstract
Antipsychotic treatment resistance in schizophrenia remains a major issue in psychiatry. Nearly 30% of patients with schizophrenia do not respond to antipsychotic treatment, yet the underlying neurobiological causes are unknown. All effective antipsychotic medications are thought to achieve their efficacy by targeting the dopaminergic system. Here we review early literature describing the fundamental mechanisms of antipsychotic drug efficacy, highlighting mechanistic concepts that have persisted over time. We then reconsider the original framework for understanding antipsychotic efficacy in light of recent advances in our scientific understanding of the dopaminergic effects of antipsychotics. Based on these new insights, we describe a role for the dopamine transporter in the genesis of both antipsychotic therapeutic response and primary resistance. We believe that this discussion will help delineate the dopaminergic nature of antipsychotic treatment-resistant schizophrenia.
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Affiliation(s)
- Davide Amato
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, United States
| | - Anna Kruyer
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, United States
| | - Anne-Noël Samaha
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Andreas Heinz
- Department of Psychiatry, Charité University Medicine Berlin, Campus Charité Mitte, Berlin, Germany
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Nakao K, Jeevakumar V, Jiang SZ, Fujita Y, Diaz NB, Pretell Annan CA, Eskow Jaunarajs KL, Hashimoto K, Belforte JE, Nakazawa K. Schizophrenia-Like Dopamine Release Abnormalities in a Mouse Model of NMDA Receptor Hypofunction. Schizophr Bull 2019; 45:138-147. [PMID: 29394409 PMCID: PMC6293233 DOI: 10.1093/schbul/sby003] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Amphetamine-induced augmentation of striatal dopamine and its blunted release in prefrontal cortex (PFC) is a hallmark of schizophrenia pathophysiology. Although N-methyl-D-aspartate receptor (NMDAR) hypofunction is also implicated in schizophrenia, it remains unclear whether NMDAR hypofunction leads to dopamine release abnormalities. We previously demonstrated schizophrenia-like phenotypes in GABAergic neuron-specific NMDAR hypofunctional mutant mice, in which Ppp1r2-Cre dependent deletion of indispensable NMDAR channel subunit Grin1 is induced in corticolimbic GABAergic neurons including parvalbumin (PV)-positive neurons, in postnatal development, but not in adulthood. Here, we report enhanced dopaminomimetic-induced locomotor activity in these mutants, along with bidirectional, site-specific changes in in vivo amphetamine-induced dopamine release: nucleus accumbens (NAc) dopamine release was enhanced by amphetamine in postnatal Ppp1r2-Cre/Grin1 knockout (KO) mice, whereas dopamine release was dramatically reduced in the medial PFC (mPFC) compared to controls. Basal tissue dopamine levels in both the NAc and mPFC were unaffected. Interestingly, the magnitude and distribution of amphetamine-induced c-Fos expression in dopamine neurons was comparable between genotypes across dopaminergic input subregions in the ventral tegmental area (VTA). These effects appear to be both developmentally and cell-type specifically modulated, since PV-specific Grin1 KO mice could induce the same effects as seen in postnatal-onset Ppp1r2-Cre/Grin1 KO mice, but no such abnormalities were observed in somatostatin-Cre/Grin1 KO mice or adult-onset Ppp1r2-Cre/Grin1 KO mice. These results suggest that PV GABAergic neuron-NMDAR hypofunction in postnatal development confers bidirectional NAc hyper- and mPFC hypo-sensitivity to amphetamine-induced dopamine release, similar to that classically observed in schizophrenia pathophysiology.
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Affiliation(s)
- Kazuhito Nakao
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL,Unit on Genetics of Cognition and Behavior, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Vivek Jeevakumar
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL
| | - Sunny Zhihong Jiang
- Unit on Genetics of Cognition and Behavior, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Yuko Fujita
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan
| | - Noelia B Diaz
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires and Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carlos A Pretell Annan
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires and Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Kenji Hashimoto
- Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan
| | - Juan E Belforte
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires and Instituto de Fisiología y Biofísica “Bernardo Houssay” (IFIBIO-Houssay), Grupo de Neurociencia de Sistemas, CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Kazu Nakazawa
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL,Unit on Genetics of Cognition and Behavior, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, MD,To whom correspondence should be addressed; Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, 1825 University Boulevard, Birmingham, AL 35294, US; tel: 205-996-6877, e-mail:
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Dopamine perturbation of gene co-expression networks reveals differential response in schizophrenia for translational machinery. Transl Psychiatry 2018; 8:278. [PMID: 30546022 PMCID: PMC6293320 DOI: 10.1038/s41398-018-0325-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 11/13/2018] [Indexed: 12/02/2022] Open
Abstract
The dopaminergic hypothesis of schizophrenia (SZ) postulates that positive symptoms of SZ, in particular psychosis, are due to disturbed neurotransmission via the dopamine (DA) receptor D2 (DRD2). However, DA is a reactive molecule that yields various oxidative species, and thus has important non-receptor-mediated effects, with empirical evidence of cellular toxicity and neurodegeneration. Here we examine non-receptor-mediated effects of DA on gene co-expression networks and its potential role in SZ pathology. Transcriptomic profiles were measured by RNA-seq in B-cell transformed lymphoblastoid cell lines from 514 SZ cases and 690 controls, both before and after exposure to DA ex vivo (100 μM). Gene co-expression modules were identified using Weighted Gene Co-expression Network Analysis for both baseline and DA-stimulated conditions, with each module characterized for biological function and tested for association with SZ status and SNPs from a genome-wide panel. We identified seven co-expression modules under baseline, of which six were preserved in DA-stimulated data. One module shows significantly increased association with SZ after DA perturbation (baseline: P = 0.023; DA-stimulated: P = 7.8 × 10-5; ΔAIC = -10.5) and is highly enriched for genes related to ribosomal proteins and translation (FDR = 4 × 10-141), mitochondrial oxidative phosphorylation, and neurodegeneration. SNP association testing revealed tentative QTLs underlying module co-expression, notably at FASTKD2 (top P = 2.8 × 10-6), a gene involved in mitochondrial translation. These results substantiate the role of translational machinery in SZ pathogenesis, providing insights into a possible dopaminergic mechanism disrupting mitochondrial function, and demonstrates the utility of disease-relevant functional perturbation in the study of complex genetic etiologies.
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Lucatch AM, Lowe DJE, Clark RC, Kozak K, George TP. Neurobiological Determinants of Tobacco Smoking in Schizophrenia. Front Psychiatry 2018; 9:672. [PMID: 30574101 PMCID: PMC6291492 DOI: 10.3389/fpsyt.2018.00672] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/21/2018] [Indexed: 12/22/2022] Open
Abstract
Purpose of review: To provide an overview of the underlying neurobiology of tobacco smoking in schizophrenia, and implications for treatment of this comorbidity. Recent findings: Explanations for heavy tobacco smoking in schizophrenia include pro-cognitive effects of nicotine, and remediation of the underlying pathophysiology of schizophrenia. Nicotine may ameliorate neurochemical deficits through nicotine acetylcholine receptors (nAChRs) located on the dopamine, glutamate, and GABA neurons. Neurophysiological indices including electroencephalography, electromyography, and smooth pursuit eye movement (SPEM) paradigms may be biomarkers for underlying neuronal imbalances that contribute to the specific risk of tobacco smoking initiation, maintenance, and difficulty quitting within schizophrenia. Moreover, several social factors including socioeconomic factors and permissive smoking culture in mental health facilities, may contribute to the smoking behaviors (initiation, maintenance, and inability to quit smoking) within this disorder. Summary: Tobacco smoking may alleviate specific symptoms associated with schizophrenia. Understanding the neurobiological underpinnings and psychosocial determinants of this comorbidity may better explain these potential beneficial effects, while also providing important insights into effective treatments for smoking cessation.
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Affiliation(s)
- Aliya M. Lucatch
- Addictions Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Darby J. E. Lowe
- Addictions Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Rachel C. Clark
- Addictions Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
| | - Karolina Kozak
- Addictions Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Tony P. George
- Addictions Division, Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Division and Brain and Therapeutics, Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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De Felice M, Melis M, Aroni S, Muntoni AL, Fanni S, Frau R, Devoto P, Pistis M. The PPARα agonist fenofibrate attenuates disruption of dopamine function in a maternal immune activation rat model of schizophrenia. CNS Neurosci Ther 2018; 25:549-561. [PMID: 30461214 PMCID: PMC6488881 DOI: 10.1111/cns.13087] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 10/22/2018] [Accepted: 10/26/2018] [Indexed: 12/15/2022] Open
Abstract
Aims Prenatal maternal immune activation (MIA) is associated with a risk to develop schizophrenia and affects dopamine systems in the ventral tegmental area (VTA), key region in the neurobiology of psychoses. Considering the well‐described sex differences in schizophrenia, we investigated whether sex affects MIA impact on dopamine system and on schizophrenia‐related behavioral phenotype. Furthermore, considering peroxisome proliferator‐activated receptor‐α (PPARα) expression in the CNS as well as its anti‐inflammatory and neuroprotective properties, we tested if PPARα activation by prenatal treatment with a clinically available fibrate (fenofibrate) may mitigate MIA‐related effects. Methods We induced MIA in rat dams with polyriboinosinic‐polyribocytidylic acid (Poly I:C) and assessed prepulse inhibition and dopamine neuron activity in the VTA by means of electrophysiological recordings in male and female preweaned and adult offspring. Results Poly I:C‐treated males displayed prepulse inhibition deficits, reduced number and firing rate of VTA dopamine neurons, and paired‐pulse facilitation of inhibitory and excitatory synapses. Prenatal fenofibrate administration attenuated detrimental effects induced by MIA on both the schizophrenia‐like behavioral phenotype and dopamine transmission in male offspring. Conclusion Our study confirms previous evidence that females are less susceptible to MIA and highlights PPARα as a potential target for treatments in schizophrenia.
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Affiliation(s)
- Marta De Felice
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Miriam Melis
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Sonia Aroni
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Anna Lisa Muntoni
- Section of Cagliari, Neuroscience Institute, National Research Council of Italy (CNR), Monserrato, Italy
| | - Silvia Fanni
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Roberto Frau
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Paola Devoto
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Marco Pistis
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy.,Section of Cagliari, Neuroscience Institute, National Research Council of Italy (CNR), Monserrato, Italy
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40
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McCutcheon R, Beck K, Jauhar S, Howes OD. Defining the Locus of Dopaminergic Dysfunction in Schizophrenia: A Meta-analysis and Test of the Mesolimbic Hypothesis. Schizophr Bull 2018; 44:1301-1311. [PMID: 29301039 PMCID: PMC5933516 DOI: 10.1093/schbul/sbx180] [Citation(s) in RCA: 150] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Studies using positron emission tomography to image striatal dopamine function, have demonstrated that individuals with schizophrenia display increases in presynaptic function. Mesolimbic dysfunction specifically, has previously been suggested to underlie psychotic symptoms. This has not been directly tested in vivo, and the precise anatomical locus of dopamine dysfunction within the striatum remains unclear. The current article investigates the magnitude of dopaminergic abnormalities in individuals with schizophrenia, and determines how the magnitude of abnormality varies across functional subdivisions of the striatum. METHODS EMBASE, PsychINFO, and MEDLINE were searched from January 1, 1960, to December 1, 2016. Inclusion criteria were molecular imaging studies that had measured presynaptic striatal dopamine functioning. Effects sizes for whole striatum and functional subdivisions were calculated separately. The magnitude of difference between functional subdivisions in patients and controls was meta-analyzed. RESULTS Twenty-one eligible studies were identified, including 269 patients and 313 controls. Individuals with schizophrenia (Hedges' g = 0.68, P < .001) demonstrated elevated presynaptic dopamine functioning compared to controls. Seven studies examined functional subdivisions. These demonstrated significant increases in patients compared to controls in associative (g = 0.73, P = .002) and sensorimotor (g = 0.54, P = .005) regions, but not limbic (g = 0.29, P = .09). The magnitude of the difference between associative and limbic subdivisions was significantly greater in patients compared to controls (g = 0.39, P = .003). CONCLUSION In individuals with schizophrenia dopaminergic dysfunction is greater in dorsal compared to limbic subdivisions of the striatum. This is inconsistent with the mesolimbic hypothesis and identifies the dorsal striatum as a target for novel treatment development.
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Affiliation(s)
- Robert McCutcheon
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,MRC London Institute of Medical Sciences, Hammersmith Hospital, London, UK,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK,South London and Maudsley NHS Foundation Trust, London, UK
| | - Katherine Beck
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,MRC London Institute of Medical Sciences, Hammersmith Hospital, London, UK,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK,South London and Maudsley NHS Foundation Trust, London, UK
| | - Sameer Jauhar
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,MRC London Institute of Medical Sciences, Hammersmith Hospital, London, UK,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK,South London and Maudsley NHS Foundation Trust, London, UK
| | - Oliver D Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK,MRC London Institute of Medical Sciences, Hammersmith Hospital, London, UK,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK,South London and Maudsley NHS Foundation Trust, London, UK,To whom correspondence should be addressed; Institute of Psychiatry, Psychology & Neuroscience,King’s College London, Box 67, De Crespigny Park, Camberwell, London SE5 8AF, UK; tel: +44-207-848-0355, e-mail:
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Joo YH, Kim JH, Son YD, Kim HK, Shin YJ, Lee SY, Kim JH. The relationship between excitement symptom severity and extrastriatal dopamine D 2/3 receptor availability in patients with schizophrenia: a high-resolution PET study with [ 18F]fallypride. Eur Arch Psychiatry Clin Neurosci 2018. [PMID: 28623450 DOI: 10.1007/s00406-017-0821-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The purpose of this study was to investigate the relationship between specific symptom severity and D2/3 receptor availability in extrastriatal regions in outpatients with schizophrenia to shed light on the role of extrastriatal dopaminergic neurotransmission in the pathophysiology of symptoms of schizophrenia. Sixteen schizophrenia patients receiving relatively low-dose maintenance atypical antipsychotics and seventeen healthy controls underwent 3-Tesla magnetic resonance imaging and high-resolution positron emission tomography with [18F]fallypride. For D2/3 receptor availability, the binding potential with respect to non-displaceable compartment (BPND) was derived using the simplified reference tissue model. The BPND values were lower in patients on antipsychotic treatment than in controls across all regions with large effect sizes (1.03-1.42). The regions with the largest effect size were the substantia nigra, amygdala, and insula. Symptoms of schizophrenia were assessed using a five-factor model of the Positive and Negative Syndrome Scale (PANSS). The region of interest-based analysis showed that PANSS excitement factor score had a significant positive correlation with the [18F]fallypride BPND in the insula. The equivalent dose of antipsychotics was not significantly correlated with PANSS factor scores or regional BPND values. The voxel-based analysis also revealed a significant positive association between the PANSS excitement factor and the [18F]fallypride BPND in the insula. The present study revealed a significant association between excitement symptom severity and D2/3 receptor availability in the insula in schizophrenia, suggesting a possible important role of D2/3 receptor-mediated neurotransmission in the insula and related limbic system in the pathophysiology of this specific symptom cluster.
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Affiliation(s)
- Yo-Han Joo
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea
| | - Jeong-Hee Kim
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea.,Research Institute for Advanced Industrial Technology, Korea University, Sejong, Republic of Korea
| | - Young-Don Son
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea.,Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon, Republic of Korea
| | - Hang-Keun Kim
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea.,Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon, Republic of Korea
| | - Yeon-Jeong Shin
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea
| | - Sang-Yoon Lee
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea.,Department of Radiological Science, College of Health Science, Gachon University, Incheon, Republic of Korea
| | - Jong-Hoon Kim
- Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea. .,Department of Psychiatry, Neuroscience Research Institute, Gil Medical Center, Gachon University School of Medicine, Gachon University, 1198 Guwol-dong, Namdong-gu, Incheon, 405-760, Republic of Korea.
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Duan J, Göring HHH, Sanders AR, Moy W, Freda J, Drigalenko EI, Kos M, He D, Gejman PV. Transcriptomic signatures of schizophrenia revealed by dopamine perturbation in an ex vivo model. Transl Psychiatry 2018; 8:158. [PMID: 30115913 PMCID: PMC6095865 DOI: 10.1038/s41398-018-0216-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The dopaminergic hypothesis of schizophrenia (SZ) postulates that dopaminergic over activity causes psychosis, a central feature of SZ, based on the observation that blocking dopamine (DA) improves psychotic symptoms. DA is known to have both receptor- and non-receptor-mediated effects, including oxidative mechanisms that lead to apoptosis. The role of DA-mediated oxidative processes in SZ has been little studied. Here, we have used a cell perturbation approach and measured transcriptomic profiles by RNAseq to study the effect of DA exposure on transcription in B-cell transformed lymphoblastoid cell lines (LCLs) from 514 SZ cases and 690 controls. We found that DA had widespread effects on both cell growth and gene expression in LCLs. Overall, 1455 genes showed statistically significant differential DA response in SZ cases and controls. This set of differentially expressed genes is enriched for brain expression and for functions related to immune processes and apoptosis, suggesting that DA may play a role in SZ pathogenesis through modulating those systems. Moreover, we observed a non-significant enrichment of genes near genome-wide significant SZ loci and with genes spanned by SZ-associated copy number variants (CNVs), which suggests convergent pathogenic mechanisms detected by both genetic association and gene expression. The study suggests a novel role of DA in the biological processes of immune and apoptosis that may be relevant to SZ pathogenesis. Furthermore, our results show the utility of pathophysiologically relevant perturbation experiments to investigate the biology of complex mental disorders.
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Affiliation(s)
- Jubao Duan
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA.
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA.
| | - Harald H H Göring
- South Texas Diabetes and Obesity Institute, University of Texas Rio Grande Valley School of Medicine, San Antonio, TX, USA
| | - Alan R Sanders
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - Winton Moy
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - Jessica Freda
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA
| | - Eugene I Drigalenko
- Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA
| | - Mark Kos
- South Texas Diabetes and Obesity Institute, University of Texas Rio Grande Valley School of Medicine, San Antonio, TX, USA
| | - Deli He
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA
| | - Pablo V Gejman
- Center for Psychiatric Genetics, NorthShore University HealthSystem, Evanston, IL, USA.
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA.
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Olney JJ, Warlow SM, Naffziger EE, Berridge KC. Current perspectives on incentive salience and applications to clinical disorders. Curr Opin Behav Sci 2018; 22:59-69. [PMID: 29503841 PMCID: PMC5831552 DOI: 10.1016/j.cobeha.2018.01.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Affective neuroscience research has revealed that reward contains separable components of 'liking', 'wanting', and learning. Here we focus on current 'liking' and 'wanting' findings and applications to clinical disorders. 'Liking' is the hedonic impact derived from a pleasant experience, and is amplified by opioid and related signals in discrete sites located in limbic-related brain areas. 'Wanting' refers to incentive salience, a motivation process for reward, and is mediated by larger systems involving mesocorticolimbic dopamine. Deficits in incentive salience may contribute to avolitional features of depression and related disorders, whereas deficits in hedonic impact may produce true anhedonia. Excesses in incentive salience, on the other hand, can lead to addiction, especially when narrowly focused on a particular target. Finally, a fearful form of motivational salience may even contribute to some paranoia symptoms of schizophrenia and related disorders.
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Affiliation(s)
- Jeffrey J Olney
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109
| | - Shelley M Warlow
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109
| | - Erin E Naffziger
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109
| | - Kent C Berridge
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109
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Weinstein JJ, van de Giessen E, Rosengard RJ, Xu X, Ojeil N, Brucato G, Gil RB, Kegeles LS, Laruelle M, Slifstein M, Abi-Dargham A. PET imaging of dopamine-D2 receptor internalization in schizophrenia. Mol Psychiatry 2018; 23:1506-1511. [PMID: 28507321 PMCID: PMC5690884 DOI: 10.1038/mp.2017.107] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/22/2017] [Accepted: 04/04/2017] [Indexed: 02/07/2023]
Abstract
Recent genetic, molecular and post-mortem studies suggest impaired dopamine (DA)-D2 receptor (D2R) trafficking in patients with schizophrenia (SZ). Imaging and preclinical studies have shown agonist-induced D2R internalization can be imaged with positron emission tomography (PET) using D2R radiotracers combined with psychostimulant challenge. This is feasible if radiotracer binding is measured when postchallenge DA levels have returned to baseline, following the initial competition phase between DA and radiotracer for binding to D2R. Here we used 'late-phase' imaging after challenge to test the hypothesis that impaired D2R internalization in SZ leads to blunted late-phase displacement, or a faster return to baseline, in patients compared with healthy controls (HCs). We imaged 10 patients with SZ and 9 HCs with PET and [11C]raclopride at baseline and two times (3-5 and 6-10 h) following 0.5 mg kg-1 dextroamphetamine. We measured binding potential relative to non-displaceable compartment (BPND) and derived percent reduction from baseline (ΔBPND) for each postamphetamine scan. To test the hypothesis that time course of return of striatal BPND to baseline differed between SZ and HCs, we implemented a linear model with ΔBPND as dependent variable, time after amphetamine as repeated measure and time after amphetamine and diagnostic group as fixed effects. Neither diagnostic group nor interaction of diagnostic group-by-time after amphetamine significantly affected striatal ΔBPND (F=1.38, P=0.26; F=0.51, P=0.61). These results show similar pattern of return of BPND to baseline as a function of time in patients with SZ and HC, suggesting that striatal D2R internalization as measured by our imaging paradigm is normal in patients with SZ.
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Affiliation(s)
- Jodi J. Weinstein
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York,Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York
| | | | | | - Xiaoyan Xu
- New York State Psychiatric Institute, New York, New York
| | - Najate Ojeil
- New York State Psychiatric Institute, New York, New York
| | - Gary Brucato
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York,New York State Psychiatric Institute, New York, New York
| | - Roberto B. Gil
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
| | - Lawrence S. Kegeles
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York,New York State Psychiatric Institute, New York, New York
| | - Marc Laruelle
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York
| | - Mark Slifstein
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
| | - Anissa Abi-Dargham
- Department of Psychiatry, Stony Brook University School of Medicine, Stony Brook, New York
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Gill KM, Miller SA, Grace AA. Impaired contextual fear-conditioning in MAM rodent model of schizophrenia. Schizophr Res 2018; 195:343-352. [PMID: 28927551 PMCID: PMC5854517 DOI: 10.1016/j.schres.2017.08.064] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/31/2017] [Accepted: 08/31/2017] [Indexed: 12/19/2022]
Abstract
The methylazoxymethanol acetate (MAM) rodent neurodevelopmental model of schizophrenia exhibits aberrant dopamine system activation attributed to hippocampal dysfunction. Context discrimination is a component of numerous behavioral and cognitive functions and relies on intact hippocampal processing. The present study explored context processing behaviors, along with dopamine system activation, during fear learning in the MAM model. Male offspring of dams treated with MAM (20mg/kg, i.p.) or saline on gestational day 17 were used for electrophysiological and behavioral experiments. Animals were tested on the immediate shock fear conditioning paradigm, with either different pre-conditioning contexts or varying amounts of context pre-exposure (0-10 sessions). Amphetamine-induced locomotor activity and dopamine neural activity was measured 1-week after fear conditioning. Saline, but not MAM animals, demonstrated enhanced fear responses following a single context pre-exposure in the conditioning context. One week following fear learning, saline rats with 2 or 7min of context pre-exposure prior to fear conditioning also demonstrated enhanced amphetamine-induced locomotor response relative to MAM animals. Dopamine neuron recordings showed fear learning-induced reductions in spontaneous dopamine neural activity in MAM rats that was further reduced by amphetamine. Apomorphine administration confirmed that reductions in dopamine neuron activity in MAM animals resulted from over excitation, or depolarization block. These data show a behavioral insensitivity to contextual stimuli in MAM rats that coincide with a less dynamic dopamine response after fear learning.
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Nour MM, McCutcheon R, Howes OD. The Relationship Between Dopamine Synthesis Capacity and Release: Implications for Psychosis. Neuropsychopharmacology 2018; 43:1195-1196. [PMID: 29670249 PMCID: PMC5916363 DOI: 10.1038/npp.2017.293] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Matthew M Nour
- Psychiatric Imaging, Department of Psychosis Studies, Institute of Psychiatry Psychology and Neuroscience, King’s College London, London, UK,Department of Psychosis Studies, Institute of Psychiatry Psychology and Neuroscience, King’s College London, PO63 Level 5, 16 De Crespigny Park, London, SE5 8AF, UK, Tel: +44 20 7848 0355, E-mail:
| | - Robert McCutcheon
- Psychiatric Imaging, Department of Psychosis Studies, Institute of Psychiatry Psychology and Neuroscience, King’s College London, London, UK
| | - Oliver D Howes
- Psychiatric Imaging, Department of Psychosis Studies, Institute of Psychiatry Psychology and Neuroscience, King’s College London, London, UK,MRC London Institute of Medical Sciences, Hammersmith Hospital Campus, London, UK
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Kegeles LS, Horga G, Ghazzaoui R, Rosengard R, Ojeil N, Xu X, Slifstein M, Petrakis I, O'Malley SS, Krystal JH, Abi-Dargham A. Enhanced Striatal Dopamine Release to Expectation of Alcohol: A Potential Risk Factor for Alcohol Use Disorder. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2018; 3:591-598. [PMID: 29803635 DOI: 10.1016/j.bpsc.2018.03.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/07/2018] [Accepted: 03/26/2018] [Indexed: 01/08/2023]
Abstract
BACKGROUND We used positron emission tomography imaging with [11C]raclopride to examine the effects of consumption of alcohol or placebo beverage by participants with alcohol use disorder (AUD) compared with healthy participants with and without family history of AUD. We sought to assess dopamine release following alcohol exposure in relation to AUD risk. METHODS Three groups were enrolled: participants with AUD (n = 15) and healthy participants with family history negative (n = 34) or positive (n = 16) for AUD. Participants consumed a placebo (n = 65) or alcohol (n = 63) beverage in counterbalanced order before positron emission tomography scanning (128 scans). Binding potential (BPND) in the two drink conditions and the percent change in BPND between conditions were evaluated across striatal subregions. Subjective effects of beverage consumption were rated. Effects of group, drink order, and sex were evaluated. RESULTS Alcohol resulted in greater dopamine release than did placebo in the ventral striatum (p < .001). There were no main effects of group, drink order, or sex on ventral striatum BPND or percent change in BPND. However, there was a drink order-by-group interaction (p = .02) whereby family history-positive participants who received placebo first had both lower placebo BPND and less difference between placebo and alcohol BPND than all other groups, consistent with expectation of alcohol powerfully evoking dopamine release in this group. Subjective responses showed the same order-by-group interaction. CONCLUSIONS Hyper-responsivity of the dopaminergic system in family history-positive participants to expectation of alcohol may contribute to the expression of familial risk for AUD.
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Affiliation(s)
- Lawrence S Kegeles
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York; Department of Radiology, Columbia University College of Physicians and Surgeons, New York, New York.
| | - Guillermo Horga
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Rassil Ghazzaoui
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Rachel Rosengard
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Najate Ojeil
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Xiaoyan Xu
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Mark Slifstein
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York
| | - Ismene Petrakis
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | | | - John H Krystal
- Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Anissa Abi-Dargham
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, New York; Department of Radiology, Columbia University College of Physicians and Surgeons, New York, New York
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48
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Frankle WG, Paris J, Himes M, Mason NS, Mathis CA, Narendran R. Amphetamine-Induced Striatal Dopamine Release Measured With an Agonist Radiotracer in Schizophrenia. Biol Psychiatry 2018; 83:707-714. [PMID: 29325847 PMCID: PMC5862747 DOI: 10.1016/j.biopsych.2017.11.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 11/29/2017] [Accepted: 11/30/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Receptor imaging studies have reported increased amphetamine-induced dopamine release in subjects with schizophrenia (SCH) relative to healthy control subjects (HCs). A limitation of these studies, performed with D2/3 antagonist radiotracers, is the failure to provide information about D2/3 receptors configured in a state of high affinity for the agonists (i.e., D2/3 receptors coupled to G proteins [D2/3 HIGH]). The endogenous agonist dopamine binds with preference to D2/3 HIGH receptors relative to D2/3 LOW receptors, making it critical to understand the status of D2/3 HIGH receptors in SCH. METHODS D2/3 agonist positron emission tomography radiotracer [11C]N-propyl-norapomorphine ([11C]NPA) binding potential (BPND) was measured in 14 off-medication subjects with SCH and 14 matched HCs at baseline and after the administration of 0.5 mg kg-1 oral D-amphetamine. The amphetamine-induced change in BPND (ΔBPND) was calculated as the difference between BPND in the postamphetamine condition and BPND in the baseline condition and was expressed as a percentage of BPND at baseline. RESULTS A trend-level increase was observed in comparing baseline [11C]NPA BPND (repeated-measures analysis of variance, F1,26 = 3.34, p = .08) between the SCH and HC groups. Amphetamine administration significantly decreased BPND in all striatal regions across all subjects in both groups. No differences were observed in [11C]NPA ΔBPND (repeated-measures analysis of variance, F1,26 = 1.9, p = .18) between HCs and subjects with SCH. Amphetamine significantly increased positive symptoms in subjects with SCH (19.5 ± 5.3 vs. 23.7 ± 4.1, paired t test, p < .0001); however, no correlations were noted with [11C]NPA BPND or ΔBPND. CONCLUSIONS This study provides in vivo indication of a role for postsynaptic factors in amphetamine-induced psychosis in SCH.
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Affiliation(s)
- W Gordon Frankle
- Department of Psychiatry, NYU Langone Medical Center, New York, New York.
| | - Jennifer Paris
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Michael Himes
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - N Scott Mason
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Chester A Mathis
- Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rajesh Narendran
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania
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49
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Kesby JP, Eyles DW, McGrath JJ, Scott JG. Dopamine, psychosis and schizophrenia: the widening gap between basic and clinical neuroscience. Transl Psychiatry 2018; 8:30. [PMID: 29382821 PMCID: PMC5802623 DOI: 10.1038/s41398-017-0071-9] [Citation(s) in RCA: 182] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/10/2017] [Accepted: 10/26/2017] [Indexed: 12/18/2022] Open
Abstract
The stagnation in drug development for schizophrenia highlights the need for better translation between basic and clinical research. Understanding the neurobiology of schizophrenia presents substantial challenges but a key feature continues to be the involvement of subcortical dopaminergic dysfunction in those with psychotic symptoms. Our contemporary knowledge regarding dopamine dysfunction has clarified where and when dopaminergic alterations may present in schizophrenia. For example, clinical studies have shown patients with schizophrenia show increased presynaptic dopamine function in the associative striatum, rather than the limbic striatum as previously presumed. Furthermore, subjects deemed at high risk of developing schizophrenia show similar presynaptic dopamine abnormalities in the associative striatum. Thus, our view of subcortical dopamine function in schizophrenia continues to evolve as we accommodate this newly acquired information. However, basic research in animal models has been slow to incorporate these clinical findings. For example, psychostimulant-induced locomotion, the commonly utilised phenotype for positive symptoms in rodents, is heavily associated with dopaminergic activation in the limbic striatum. This anatomical misalignment has brought into question how we assess positive symptoms in animal models and represents an opportunity for improved translation between basic and clinical research. The current review focuses on the role of subcortical dopamine dysfunction in psychosis and schizophrenia. We present and discuss alternative phenotypes that may provide a more translational approach to assess the neurobiology of positive symptoms in schizophrenia. Incorporation of recent clinical findings is essential if we are to develop meaningful translational animal models.
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Affiliation(s)
- JP Kesby
- 0000 0000 9320 7537grid.1003.2Queensland Brain Institute, The University of Queensland, St. Lucia, QLD Australia ,0000 0000 9320 7537grid.1003.2Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD Australia
| | - DW Eyles
- 0000 0000 9320 7537grid.1003.2Queensland Brain Institute, The University of Queensland, St. Lucia, QLD Australia ,0000 0004 0606 3563grid.417162.7Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD Australia
| | - JJ McGrath
- 0000 0000 9320 7537grid.1003.2Queensland Brain Institute, The University of Queensland, St. Lucia, QLD Australia ,0000 0004 0606 3563grid.417162.7Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD Australia ,0000 0001 1956 2722grid.7048.bNational Centre for Register-based Research, Aarhus University, Aarhus C, Denmark
| | - JG Scott
- 0000 0000 9320 7537grid.1003.2Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD Australia ,0000 0004 0606 3563grid.417162.7Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD Australia ,0000 0001 0688 4634grid.416100.2Metro North Mental Health, Royal Brisbane and Women’s Hospital, Herston, QLD Australia
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50
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Kirschner M, Hager OM, Muff L, Bischof M, Hartmann-Riemer MN, Kluge A, Habermeyer B, Seifritz E, Tobler PN, Kaiser S. Ventral Striatal Dysfunction and Symptom Expression in Individuals With Schizotypal Personality Traits and Early Psychosis. Schizophr Bull 2018; 44:147-157. [PMID: 27798223 PMCID: PMC5767950 DOI: 10.1093/schbul/sbw142] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Striatal abnormalities play a crucial role in the pathophysiology of schizophrenia. Growing evidence suggests an association between aberrant striatal activity during reward anticipation and symptom dimensions in schizophrenia. However, it is not clear whether this holds across the psychosis continuum. The aim of the present study was to investigate alterations of ventral striatal activation during reward anticipation and its relationship to symptom expression in persons with schizotypal personality traits (SPT) and first-episode psychosis. Twenty-six individuals with high SPT, 26 patients with non-affective first-episode psychosis (including 13 with brief psychotic disorder (FEP-BPD) and 13 with first-episode schizophrenia [FEP-SZ]) and 25 healthy controls underwent event-related functional magnetic resonance imaging while performing a variant of the Monetary Incentive Delay task. Ventral striatal activation was positively correlated with total symptom severity, in particular with levels of positive symptoms. This association was observed across the psychosis continuum and within each subgroup. Patients with FEP-SZ showed the strongest elevation of striatal activation during reward anticipation, although symptom levels did not differ between groups in the psychosis continuum. While our results provide evidence that variance in striatal activation is mainly explained by dimensional symptom expression, patients with schizophrenia show an additional dysregulation of striatal activation. Trans-diagnostic approaches are promising in order to disentangle dimensional and categorical neural mechanisms in the psychosis continuum.
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Affiliation(s)
- Matthias Kirschner
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland,To whom correspondence should be addressed; Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland; tel: +41-44-384-36-14, fax: +41-44-383-44-56, e-mail:
| | - Oliver M Hager
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland,Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Zurich, Switzerland
| | - Larissa Muff
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Martin Bischof
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Matthias N Hartmann-Riemer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland,Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Zurich, Switzerland
| | - Agne Kluge
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Benedikt Habermeyer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Erich Seifritz
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Philippe N Tobler
- Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Zurich, Switzerland
| | - Stefan Kaiser
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
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