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Sanchez-Rodriguez LM, Bezgin G, Carbonell F, Therriault J, Fernandez-Arias J, Servaes S, Rahmouni N, Tissot C, Stevenson J, Karikari TK, Ashton NJ, Benedet AL, Zetterberg H, Blennow K, Triana-Baltzer G, Kolb HC, Rosa-Neto P, Iturria-Medina Y. Personalized whole-brain neural mass models reveal combined Aβ and tau hyperexcitable influences in Alzheimer's disease. Commun Biol 2024; 7:528. [PMID: 38704445 DOI: 10.1038/s42003-024-06217-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 04/19/2024] [Indexed: 05/06/2024] Open
Abstract
Neuronal dysfunction and cognitive deterioration in Alzheimer's disease (AD) are likely caused by multiple pathophysiological factors. However, mechanistic evidence in humans remains scarce, requiring improved non-invasive techniques and integrative models. We introduce personalized AD computational models built on whole-brain Wilson-Cowan oscillators and incorporating resting-state functional MRI, amyloid-β (Aβ) and tau-PET from 132 individuals in the AD spectrum to evaluate the direct impact of toxic protein deposition on neuronal activity. This subject-specific approach uncovers key patho-mechanistic interactions, including synergistic Aβ and tau effects on cognitive impairment and neuronal excitability increases with disease progression. The data-derived neuronal excitability values strongly predict clinically relevant AD plasma biomarker concentrations (p-tau217, p-tau231, p-tau181, GFAP) and grey matter atrophy obtained through voxel-based morphometry. Furthermore, reconstructed EEG proxy quantities show the hallmark AD electrophysiological alterations (theta band activity enhancement and alpha reductions) which occur with Aβ-positivity and after limbic tau involvement. Microglial activation influences on neuronal activity are less definitive, potentially due to neuroimaging limitations in mapping neuroprotective vs detrimental activation phenotypes. Mechanistic brain activity models can further clarify intricate neurodegenerative processes and accelerate preventive/treatment interventions.
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Affiliation(s)
- Lazaro M Sanchez-Rodriguez
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
| | - Gleb Bezgin
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | | | - Joseph Therriault
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Jaime Fernandez-Arias
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Stijn Servaes
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Nesrine Rahmouni
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Cécile Tissot
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
- Lawrence Berkeley National Laboratory, Berkeley, USA
| | - Jenna Stevenson
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Thomas K Karikari
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nicholas J Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- King's College London, Institute of Psychiatry, Psychology and Neuroscience Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
- Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway
| | - Andréa L Benedet
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | | | - Hartmuth C Kolb
- Neuroscience Biomarkers, Janssen Research & Development, La Jolla, CA, USA
| | - Pedro Rosa-Neto
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, QC, Canada
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada.
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Adewale Q, Khan AF, Bennett DA, Iturria-Medina Y. Single-nucleus RNA velocity reveals critical synaptic and cell-cycle dysregulations in neuropathologically confirmed Alzheimer's disease. Sci Rep 2024; 14:7269. [PMID: 38538816 PMCID: PMC10973452 DOI: 10.1038/s41598-024-57918-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 03/21/2024] [Indexed: 04/26/2024] Open
Abstract
Typical differential single-nucleus gene expression (snRNA-seq) analyses in Alzheimer's disease (AD) provide fixed snapshots of cellular alterations, making the accurate detection of temporal cell changes challenging. To characterize the dynamic cellular and transcriptomic differences in AD neuropathology, we apply the novel concept of RNA velocity to the study of single-nucleus RNA from the cortex of 60 subjects with varied levels of AD pathology. RNA velocity captures the rate of change of gene expression by comparing intronic and exonic sequence counts. We performed differential analyses to find the significant genes driving both cell type-specific RNA velocity and expression differences in AD, extensively compared these two transcriptomic metrics, and clarified their associations with multiple neuropathologic traits. The results were cross-validated in an independent dataset. Comparison of AD pathology-associated RNA velocity with parallel gene expression differences reveals sets of genes and molecular pathways that underlie the dynamic and static regimes of cell type-specific dysregulations underlying the disease. Differential RNA velocity and its linked progressive neuropathology point to significant dysregulations in synaptic organization and cell development across cell types. Notably, most of the genes underlying this synaptic dysregulation showed increased RNA velocity in AD subjects compared to controls. Accelerated cell changes were also observed in the AD subjects, suggesting that the precocious depletion of precursor cell pools might be associated with neurodegeneration. Overall, this study uncovers active molecular drivers of the spatiotemporal alterations in AD and offers novel insights towards gene- and cell-centric therapeutic strategies accounting for dynamic cell perturbations and synaptic disruptions.
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Affiliation(s)
- Quadri Adewale
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada
| | - Ahmed F Khan
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Y I-M, 3801 University Street, Room NW312, Montreal, H3A 2B4, Canada.
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada.
- Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada.
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Pak V, Adewale Q, Bzdok D, Dadar M, Zeighami Y, Iturria-Medina Y. Distinctive whole-brain cell types predict tissue damage patterns in thirteen neurodegenerative conditions. eLife 2024; 12:RP89368. [PMID: 38512130 PMCID: PMC10957173 DOI: 10.7554/elife.89368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024] Open
Abstract
For over a century, brain research narrative has mainly centered on neuron cells. Accordingly, most neurodegenerative studies focus on neuronal dysfunction and their selective vulnerability, while we lack comprehensive analyses of other major cell types' contribution. By unifying spatial gene expression, structural MRI, and cell deconvolution, here we describe how the human brain distribution of canonical cell types extensively predicts tissue damage in 13 neurodegenerative conditions, including early- and late-onset Alzheimer's disease, Parkinson's disease, dementia with Lewy bodies, amyotrophic lateral sclerosis, mutations in presenilin-1, and 3 clinical variants of frontotemporal lobar degeneration (behavioral variant, semantic and non-fluent primary progressive aphasia) along with associated three-repeat and four-repeat tauopathies and TDP43 proteinopathies types A and C. We reconstructed comprehensive whole-brain reference maps of cellular abundance for six major cell types and identified characteristic axes of spatial overlapping with atrophy. Our results support the strong mediating role of non-neuronal cells, primarily microglia and astrocytes, in spatial vulnerability to tissue loss in neurodegeneration, with distinct and shared across-disorder pathomechanisms. These observations provide critical insights into the multicellular pathophysiology underlying spatiotemporal advance in neurodegeneration. Notably, they also emphasize the need to exceed the current neuro-centric view of brain diseases, supporting the imperative for cell-specific therapeutic targets in neurodegeneration.
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Affiliation(s)
- Veronika Pak
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
| | - Quadri Adewale
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
| | - Danilo Bzdok
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Department of Biomedical Engineering, McGill UniversityMontrealCanada
- School of Computer Science, McGill UniversityMontrealCanada
- Mila – Quebec Artificial Intelligence InstituteMontrealCanada
| | | | | | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological InstituteMontrealCanada
- Ludmer Centre for Neuroinformatics & Mental HealthMontrealCanada
- Department of Biomedical Engineering, McGill UniversityMontrealCanada
- McGill Centre for Studies in AgingMontrealCanada
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Tremblay SA, Alasmar Z, Pirhadi A, Carbonell F, Iturria-Medina Y, Gauthier CJ, Steele CJ. MVComp toolbox: MultiVariate Comparisons of brain MRI features accounting for common information across metrics. bioRxiv 2024:2024.02.27.582381. [PMID: 38463982 PMCID: PMC10925263 DOI: 10.1101/2024.02.27.582381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Multivariate approaches have recently gained in popularity to address the physiological unspecificity of neuroimaging metrics and to better characterize the complexity of biological processes underlying behavior. However, commonly used approaches are biased by the intrinsic associations between variables, or they are computationally expensive and may be more complicated to implement than standard univariate approaches. Here, we propose using the Mahalanobis distance (D2), an individual-level measure of deviation relative to a reference distribution that accounts for covariance between metrics. To facilitate its use, we introduce an open-source python-based tool for computing D2 relative to a reference group or within a single individual: the MultiVariate Comparison (MVComp) toolbox. The toolbox allows different levels of analysis (i.e., group- or subject-level), resolutions (e.g., voxel-wise, ROI-wise) and dimensions considered (e.g., combining MRI metrics or WM tracts). Several example cases are presented to showcase the wide range of possible applications of MVComp and to demonstrate the functionality of the toolbox. The D2 framework was applied to the assessment of white matter (WM) microstructure at 1) the group-level, where D2 can be computed between a subject and a reference group to yield an individualized measure of deviation. We observed that clustering applied to D2 in the corpus callosum yields parcellations that highly resemble known topography based on neuroanatomy, suggesting that D2 provides an integrative index that meaningfully reflects the underlying microstructure. 2) At the subject level, D2 was computed between voxels to obtain a measure of (dis)similarity. The loadings of each MRI metric (i.e., its relative contribution to D2) were then extracted in voxels of interest to showcase a useful option of the MVComp toolbox. These relative contributions can provide important insights into the physiological underpinnings of differences observed. Integrative multivariate models are crucial to expand our understanding of the complex brain-behavior relationships and the multiple factors underlying disease development and progression. Our toolbox facilitates the implementation of a useful multivariate method, making it more widely accessible.
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Affiliation(s)
- Stefanie A Tremblay
- Department of Physics, Concordia University, Montreal, Canada
- School of Health, Concordia University, Montreal, Canada
- EPIC Centre, Montreal Heart Institute, Montreal, Canada
| | - Zaki Alasmar
- School of Health, Concordia University, Montreal, Canada
- Department of Psychology, Concordia University, Montreal, Canada
| | - Amir Pirhadi
- Department of Electrical Engineering, Concordia University, Montreal, Canada
- ViTAA medical solutions, Montreal, Canada
| | | | - Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Montreal, Canada
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada
- Ludmer Center for NeuroInformatics and Mental Health, Montreal, Canada
| | - Claudine J Gauthier
- Department of Physics, Concordia University, Montreal, Canada
- School of Health, Concordia University, Montreal, Canada
- EPIC Centre, Montreal Heart Institute, Montreal, Canada
| | - Christopher J Steele
- School of Health, Concordia University, Montreal, Canada
- Department of Psychology, Concordia University, Montreal, Canada
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
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Chen J, Jiang S, Lu B, Liao J, Yang Z, Li H, Pei H, Li J, Iturria-Medina Y, Yao D, Luo C. The role of the primary sensorimotor system in generalized epilepsy: Evidence from the cerebello-cerebral functional integration. Hum Brain Mapp 2024; 45:e26551. [PMID: 38063289 PMCID: PMC10789200 DOI: 10.1002/hbm.26551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 11/12/2023] [Accepted: 11/16/2023] [Indexed: 01/16/2024] Open
Abstract
The interaction between cerebellum and cerebrum participates widely in function from motor processing to high-level cognitive and affective processing. Because of the motor symptom, idiopathic generalized epilepsy (IGE) patients with generalized tonic-clonic seizure have been recognized to associate with motor abnormalities, but the functional interaction in the cerebello-cerebral circuit is still poorly understood. Resting-state functional magnetic resonance imaging data were collected for 101 IGE patients and 106 healthy controls. The voxel-based functional connectivity (FC) between cerebral cortex and the cerebellum was contacted. The functional gradient and independent components analysis were applied to evaluate cerebello-cerebral functional integration on the voxel-based FC. Cerebellar motor components were further linked to cerebellar gradient. Results revealed cerebellar motor functional modules were closely related to cerebral motor components. The altered mapping of cerebral motor components to cerebellum was observed in motor module in patients with IGE. In addition, patients also showed compression in cerebello-cerebral functional gradient between motor and cognition modules. Interestingly, the contribution of the motor components to the gradient was unbalanced between bilateral primary sensorimotor components in patients: the increase was observed in cerebellar cognitive module for the dominant hemisphere primary sensorimotor, but the decrease was found in the cerebellar cognitive module for the nondominant hemisphere primary sensorimotor. The present findings suggest that the cerebral primary motor system affects the hierarchical architecture of cerebellum, and substantially contributes to the functional integration evidence to understand the motor functional abnormality in IGE patients.
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Affiliation(s)
- Junxia Chen
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Sisi Jiang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
- High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Bao Lu
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Jiangyan Liao
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Zhihuan Yang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Hechun Li
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
- High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Haonan Pei
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Jianfu Li
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
- High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, P. R. China
| | - Yasser Iturria-Medina
- McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Quebec, Canada
| | - Dezhong Yao
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
- High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, P. R. China
- Research Unit of NeuroInformation, Chinese Academy of Medical Sciences, Chengdu, P. R. China
| | - Cheng Luo
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, P. R. China
- High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, University of Electronic Science and Technology of China, Chengdu, P. R. China
- Research Unit of NeuroInformation, Chinese Academy of Medical Sciences, Chengdu, P. R. China
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Milisav F, Bazinet V, Iturria-Medina Y, Misic B. Resolving inter-regional communication capacity in the human connectome. Netw Neurosci 2023; 7:1051-1079. [PMID: 37781139 PMCID: PMC10473316 DOI: 10.1162/netn_a_00318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 04/03/2023] [Indexed: 10/03/2023] Open
Abstract
Applications of graph theory to the connectome have inspired several models of how neural signaling unfolds atop its structure. Analytic measures derived from these communication models have mainly been used to extract global characteristics of brain networks, obscuring potentially informative inter-regional relationships. Here we develop a simple standardization method to investigate polysynaptic communication pathways between pairs of cortical regions. This procedure allows us to determine which pairs of nodes are topologically closer and which are further than expected on the basis of their degree. We find that communication pathways delineate canonical functional systems. Relating nodal communication capacity to meta-analytic probabilistic patterns of functional specialization, we also show that areas that are most closely integrated within the network are associated with higher order cognitive functions. We find that these regions' proclivity towards functional integration could naturally arise from the brain's anatomical configuration through evenly distributed connections among multiple specialized communities. Throughout, we consider two increasingly constrained null models to disentangle the effects of the network's topology from those passively endowed by spatial embedding. Altogether, the present findings uncover relationships between polysynaptic communication pathways and the brain's functional organization across multiple topological levels of analysis and demonstrate that network integration facilitates cognitive integration.
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Affiliation(s)
- Filip Milisav
- McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Canada
| | - Vincent Bazinet
- McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Canada
| | - Yasser Iturria-Medina
- McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Canada
| | - Bratislav Misic
- McConnell Brain Imaging Centre, Montréal Neurological Institute, McGill University, Montréal, Canada
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7
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Khan AF, Adewale Q, Lin SJ, Baumeister TR, Zeighami Y, Carbonell F, Palomero-Gallagher N, Iturria-Medina Y. Patient-specific models link neurotransmitter receptor mechanisms with motor and visuospatial axes of Parkinson's disease. Nat Commun 2023; 14:6009. [PMID: 37752107 PMCID: PMC10522603 DOI: 10.1038/s41467-023-41677-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023] Open
Abstract
Parkinson's disease involves multiple neurotransmitter systems beyond the classical dopaminergic circuit, but their influence on structural and functional alterations is not well understood. Here, we use patient-specific causal brain modeling to identify latent neurotransmitter receptor-mediated mechanisms contributing to Parkinson's disease progression. Combining the spatial distribution of 15 receptors from post-mortem autoradiography with 6 neuroimaging-derived pathological factors, we detect a diverse set of receptors influencing gray matter atrophy, functional activity dysregulation, microstructural degeneration, and dendrite and dopaminergic transporter loss. Inter-individual variability in receptor mechanisms correlates with symptom severity along two distinct axes, representing motor and psychomotor symptoms with large GABAergic and glutamatergic contributions, and cholinergically-dominant visuospatial, psychiatric and memory dysfunction. Our work demonstrates that receptor architecture helps explain multi-factorial brain re-organization, and suggests that distinct, co-existing receptor-mediated processes underlie Parkinson's disease.
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Affiliation(s)
- Ahmed Faraz Khan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
| | - Quadri Adewale
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
| | - Sue-Jin Lin
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
| | - Tobias R Baumeister
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada
| | - Yashar Zeighami
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- Douglas Research Centre, Department of Psychiatry, McGill University, Montreal, QC, Canada
| | | | - Nicola Palomero-Gallagher
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany
- Cécile and Oskar Vogt Institute of Brain Research, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
- Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical Faculty, RWTH Aachen, and JARA - Translational Brain Medicine, Aachen, Germany
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada.
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, QC, Canada.
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8
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Alsharqi M, Lapidaire W, Iturria-Medina Y, Xiong Z, Williamson W, Mohamed A, Tan CMJ, Kitt J, Burchert H, Fletcher A, Whitworth P, Lewandowski AJ, Leeson P. A machine learning-based score for precise echocardiographic assessment of cardiac remodelling in hypertensive young adults. Eur Heart J Imaging Methods Pract 2023; 1:qyad029. [PMID: 37818310 PMCID: PMC10562347 DOI: 10.1093/ehjimp/qyad029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/15/2023] [Indexed: 10/12/2023]
Abstract
Aims Accurate staging of hypertension-related cardiac changes, before the development of significant left ventricular hypertrophy, could help guide early prevention advice. We evaluated whether a novel semi-supervised machine learning approach could generate a clinically meaningful summary score of cardiac remodelling in hypertension. Methods and results A contrastive trajectories inference approach was applied to data collected from three UK studies of young adults. Low-dimensional variance was identified in 66 echocardiography variables from participants with hypertension (systolic ≥160 mmHg) relative to a normotensive group (systolic < 120 mmHg) using a contrasted principal component analysis. A minimum spanning tree was constructed to derive a normalized score for each individual reflecting extent of cardiac remodelling between zero (health) and one (disease). Model stability and clinical interpretability were evaluated as well as modifiability in response to a 16-week exercise intervention. A total of 411 young adults (29 ± 6 years) were included in the analysis, and, after contrastive dimensionality reduction, 21 variables characterized >80% of data variance. Repeated scores for an individual in cross-validation were stable (root mean squared deviation = 0.1 ± 0.002) with good differentiation of normotensive and hypertensive individuals (area under the receiver operating characteristics 0.98). The derived score followed expected hypertension-related patterns in individual cardiac parameters at baseline and reduced after exercise, proportional to intervention compliance (P = 0.04) and improvement in ventilatory threshold (P = 0.01). Conclusion A quantitative score that summarizes hypertension-related cardiac remodelling in young adults can be generated from a computational model. This score might allow more personalized early prevention advice, but further evaluation of clinical applicability is required.
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Affiliation(s)
- Maryam Alsharqi
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
- Department of Cardiac Technology, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Winok Lapidaire
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, Montreal, Canada
| | - Zhaohan Xiong
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Wilby Williamson
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Afifah Mohamed
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
- Department of Diagnostic Imaging and Applied Health Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Cheryl M J Tan
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Jamie Kitt
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Holger Burchert
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Andrew Fletcher
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Polly Whitworth
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Adam J Lewandowski
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
| | - Paul Leeson
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX39DU, UK
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9
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Sanchez-Rodriguez LM, Bezgin G, Carbonell F, Therriault J, Fernandez-Arias J, Servaes S, Rahmouni N, Tissot C, Stevenson J, Karikari TK, Ashton NJ, Benedet AL, Zetterberg H, Blennow K, Triana-Baltzer G, Kolb HC, Rosa-Neto P, Iturria-Medina Y. Revealing the combined roles of Aβ and tau in Alzheimer's disease via a pathophysiological activity decoder. bioRxiv 2023:2023.02.21.529377. [PMID: 37502947 PMCID: PMC10370127 DOI: 10.1101/2023.02.21.529377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Neuronal dysfunction and cognitive deterioration in Alzheimer's disease (AD) are likely caused by multiple pathophysiological factors. However, evidence in humans remains scarce, necessitating improved non-invasive techniques and integrative mechanistic models. Here, we introduce personalized brain activity models incorporating functional MRI, amyloid-β (Aβ) and tau-PET from AD-related participants ( N = 132 ) . Within the model assumptions, electrophysiological activity is mediated by toxic protein deposition. Our integrative subject-specific approach uncovers key patho-mechanistic interactions, including synergistic Aβ and tau effects on cognitive impairment and neuronal excitability increases with disease progression. The data-derived neuronal excitability values strongly predict clinically relevant AD plasma biomarker concentrations (p-tau217, p-tau231, p-tau181, GFAP). Furthermore, our results reproduce hallmark AD electrophysiological alterations (theta band activity enhancement and alpha reductions) which occur with Aβ-positivity and after limbic tau involvement. Microglial activation influences on neuronal activity are less definitive, potentially due to neuroimaging limitations in mapping neuroprotective vs detrimental phenotypes. Mechanistic brain activity models can further clarify intricate neurodegenerative processes and accelerate preventive/treatment interventions.
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Affiliation(s)
- Lazaro M. Sanchez-Rodriguez
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada
| | - Gleb Bezgin
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | | | - Joseph Therriault
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Jaime Fernandez-Arias
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Stijn Servaes
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Nesrine Rahmouni
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Cecile Tissot
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Jenna Stevenson
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Thomas K. Karikari
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nicholas J. Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience Maurice Wohl Institute Clinical Neuroscience Institute London UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation London UK
- Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway
| | - Andréa L. Benedet
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
- Wisconsin Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal
| | | | - Hartmuth C. Kolb
- Neuroscience Biomarkers, Janssen Research & Development, La Jolla, California, USA
| | - Pedro Rosa-Neto
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada
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10
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Picher-Martel V, Magnussen C, Blais M, Bubela T, Das S, Dionne A, Evans AC, Genge A, Greiner R, Iturria-Medina Y, Johnston W, Jones K, Kaneb H, Karamchandani J, Moradipoor S, Robertson J, Rogaeva E, Taylor DM, Vande Velde C, Yunusova Y, Zinman L, Kalra S, Dupré N. CAPTURE ALS: the comprehensive analysis platform to understand, remedy and eliminate ALS. Amyotroph Lateral Scler Frontotemporal Degener 2023; 24:33-39. [PMID: 35195049 DOI: 10.1080/21678421.2022.2041668] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The absence of disease modifying treatments for amyotrophic lateral sclerosis (ALS) is in large part a consequence of its complexity and heterogeneity. Deep clinical and biological phenotyping of people living with ALS would assist in the development of effective treatments and target specific biomarkers to monitor disease progression and inform on treatment efficacy. The objective of this paper is to present the Comprehensive Analysis Platform To Understand Remedy and Eliminate ALS (CAPTURE ALS), an open and translational platform for the scientific community currently in development. CAPTURE ALS is a Canadian-based platform designed to include participants' voices in its development and through execution. Standardized methods will be used to longitudinally characterize ALS patients and healthy controls through deep clinical phenotyping, neuroimaging, neurocognitive and speech assessments, genotyping and multisource biospecimen collection. This effort plugs into complementary Canadian and international initiatives to share common resources. Here, we describe in detail the infrastructure, operating procedures, and long-term vision of CAPTURE ALS to facilitate and accelerate translational ALS research in Canada and beyond.
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Affiliation(s)
- Vincent Picher-Martel
- CERVO Brain Research Centre, Université Laval, Quebec, QC, Canada.,Neuroscience Axis, CHU de Québec - Université Laval, Quebec, QC, Canada
| | - Claire Magnussen
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Mathieu Blais
- Neuroscience Axis, CHU de Québec - Université Laval, Quebec, QC, Canada
| | - Tania Bubela
- Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Samir Das
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Annie Dionne
- Neuroscience Axis, CHU de Québec - Université Laval, Quebec, QC, Canada.,Department of Medicine, Faculty of Medicine, Université Laval, Quebec City, QC, Canada
| | - Alan C Evans
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Angela Genge
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Russell Greiner
- Department of Computing Science, Faculty of Science, Alberta Machine Intelligence Institute, University of Alberta, Edmonton, AB, Canada.,Department of Psychiatry, Faculty of Medicine and Dentistry, Alberta Machine Intelligence Institute, University of Alberta, Edmonton, AB, Canada
| | - Yasser Iturria-Medina
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Wendy Johnston
- Department of Medicine, Division of Neurology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Kelvin Jones
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Hannah Kaneb
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Jason Karamchandani
- The Montreal Neurological Institute- Hospital, McGill University Montreal, Québec, QC, Canada
| | - Sara Moradipoor
- Department of Medicine, Division of Neurology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON, Canada
| | - Ekaterina Rogaeva
- Tanz Centre for Research in Neurodegenerative Disease, University of Toronto, Toronto, ON, Canada
| | | | - Christine Vande Velde
- Department of Neurosciences, Université de Montréal, and CHUM Research Center, Montréal, QC, Canada
| | - Yana Yunusova
- Department of Speech-Language Pathology, University of Toronto, Toronto, ON, Canada, and
| | - Lorne Zinman
- Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Sanjay Kalra
- Department of Medicine, Division of Neurology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Nicolas Dupré
- Neuroscience Axis, CHU de Québec - Université Laval, Quebec, QC, Canada.,Department of Medicine, Faculty of Medicine, Université Laval, Quebec City, QC, Canada
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11
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Lacalle-Aurioles M, Iturria-Medina Y. Fornix degeneration in risk factors of Alzheimer's disease, possible trigger of cognitive decline. Cereb Circ Cogn Behav 2023; 4:100158. [PMID: 36703699 PMCID: PMC9871745 DOI: 10.1016/j.cccb.2023.100158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023]
Abstract
Risk factors of late-onset Alzheimer's disease (AD) such as aging, type 2 diabetes, obesity, heart failure, and traumatic brain injury can facilitate the appearance of cognitive decline and dementia by triggering cerebrovascular pathology and neuroinflammation. White matter (WM) microstructure and function are especially vulnerable to these conditions. Microstructural WM changes, assessed with diffusion weighted magnetic resonance imaging, can already be detected at preclinical stages of AD, and in the presence of the aforementioned risk factors. Particularly, the limbic system and cortico-cortical association WM tracts, which myelinate late during brain development, degenerate at the earliest stages. The fornix, a C-shaped WM tract that originates from the hippocampus, is one of the limbic tracts that shows early microstructural changes. Fornix integrity is necessary for ensuring an intact executive function and memory performance. Thus, a better understanding of the mechanisms that cause fornix degeneration is critical in the development of therapeutic strategies aiming to prevent cognitive decline in populations at risk. In this literature review, i) we deepen the idea that partial loss of forniceal integrity is an early event in AD, ii) we describe the role that common risk factors of AD can play in the degeneration of the fornix, and iii) we discuss some potential cellular and physiological mechanisms of WM degeneration in the scenario of cerebrovascular disease and inflammation.
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Affiliation(s)
- María Lacalle-Aurioles
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada,Corresponding author at: Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada.
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montréal, QC H3A 2B4, Canada,Ludmer Centre for Neuroinformatics and Mental Health, McGill University, Montreal, Canada,McConnell Brain Imaging Centre, McGill University, Montreal, Canada
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12
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Iturria-Medina Y, Adewale Q, Khan AF, Ducharme S, Rosa-Neto P, O’Donnell K, Petyuk VA, Gauthier S, De Jager PL, Breitner J, Bennett DA. Unified epigenomic, transcriptomic, proteomic, and metabolomic taxonomy of Alzheimer's disease progression and heterogeneity. Sci Adv 2022; 8:eabo6764. [PMID: 36399579 PMCID: PMC9674284 DOI: 10.1126/sciadv.abo6764] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Alzheimer's disease (AD) is a heterogeneous disorder with abnormalities in multiple biological domains. In an advanced machine learning analysis of postmortem brain and in vivo blood multi-omics molecular data (N = 1863), we integrated epigenomic, transcriptomic, proteomic, and metabolomic profiles into a multilevel biological AD taxonomy. We obtained a personalized multilevel molecular index of AD dementia progression that predicts severity of neuropathologies, and identified three robust molecular-based subtypes that explain much of the pathologic and clinical heterogeneity of AD. These subtypes present distinct patterns of alteration in DNA methylation, RNA, proteins, and metabolites, identifiable in the brain and subsequently in blood. In addition, the genetic variations that predispose to the various AD subtypes in brain predict distinct spatial patterns of alteration in cell types, suggesting a unique influence of each putative AD variant on neuropathological mechanisms. These observations support that an individually tailored multi-omics molecular taxonomy of AD may represent distinct targets for preventive or treatment interventions.
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Affiliation(s)
- Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, Montreal, Canada
| | - Quadri Adewale
- Neurology and Neurosurgery Department, Montreal Neurological Institute, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, Montreal, Canada
| | - Ahmed F. Khan
- Neurology and Neurosurgery Department, Montreal Neurological Institute, Montreal, Canada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Ludmer Centre for Neuroinformatics and Mental Health, Montreal, Canada
| | - Simon Ducharme
- McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Canada
| | - Pedro Rosa-Neto
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Kieran O’Donnell
- Ludmer Centre for Neuroinformatics and Mental Health, Montreal, Canada
- Yale School of Medicine, New Haven, CT 06519, USA
| | - Vladislav A. Petyuk
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Serge Gauthier
- McGill University Research Centre for Studies in Aging, Douglas Research Centre, Montreal, Canada
| | - Philip L. De Jager
- Center for Translational and Computational Neuroimmunology, Department of Neurology and Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - John Breitner
- Centre for Studies on Prevention of Alzheimer’s Disease (StoP-AD), Douglas Research Centre, Montreal, Canada
- Department of Psychiatry, McGill University, Montreal, Canada
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612, USA
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13
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Abdelnour F, Kuceyeski A, Raj A, Iturria-Medina Y, Deslauriers-Gauthier S. Editorial: Advances in brain functional and structural networks modeling via graph theory. Front Neurosci 2022; 16:1031280. [PMID: 36408385 PMCID: PMC9671134 DOI: 10.3389/fnins.2022.1031280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 09/22/2022] [Indexed: 11/06/2022] Open
Affiliation(s)
- Farras Abdelnour
- University of California, San Francisco, San Francisco, CA, United States
- *Correspondence: Farras Abdelnour
| | - Amy Kuceyeski
- Department of Radiology, Weill Cornell School of Medicine, New York, NY, United States
| | - Ashish Raj
- Department of Radiology, University of California, San Francisco, San Francisco, CA, United States
| | - Yasser Iturria-Medina
- Neurology and Neurosurgery, Ludmer Center, McConnell Brain Imaging Centre, McGill University, Montreal, QC, Canada
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14
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Levitis E, Vogel JW, Funck T, Hachinski V, Gauthier S, Vöglein J, Levin J, Gordon BA, Benzinger T, Iturria-Medina Y, Evans AC. Differentiating amyloid beta spread in autosomal dominant and sporadic Alzheimer's disease. Brain Commun 2022; 4:fcac085. [PMID: 35602652 PMCID: PMC9116976 DOI: 10.1093/braincomms/fcac085] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 12/05/2021] [Accepted: 04/08/2022] [Indexed: 11/12/2022] Open
Abstract
Amyloid-beta deposition is one of the hallmark pathologies in both sporadic Alzheimer's disease and autosomal-dominant Alzheimer's disease, the latter of which is caused by mutations in genes involved in amyloid-beta processing. Despite amyloid-beta deposition being a centrepiece to both sporadic Alzheimer's disease and autosomal-dominant Alzheimer's disease, some differences between these Alzheimer's disease subtypes have been observed with respect to the spatial pattern of amyloid-beta. Previous work has shown that the spatial pattern of amyloid-beta in individuals spanning the sporadic Alzheimer's disease spectrum can be reproduced with high accuracy using an epidemic spreading model which simulates the diffusion of amyloid-beta across neuronal connections and is constrained by individual rates of amyloid-beta production and clearance. However, it has not been investigated whether amyloid-beta deposition in the rarer autosomal-dominant Alzheimer's disease can be modelled in the same way, and if so, how congruent the spreading patterns of amyloid-beta across sporadic Alzheimer's disease and autosomal-dominant Alzheimer's disease are. We leverage the epidemic spreading model as a data-driven approach to probe individual-level variation in the spreading patterns of amyloid-beta across three different large-scale imaging datasets (2 sporadic Alzheimer's disease, 1 autosomal-dominant Alzheimer's disease). We applied the epidemic spreading model separately to the Alzheimer's Disease Neuroimaging initiative (n = 737), the Open Access Series of Imaging Studies (n = 510) and the Dominantly Inherited Alzheimer's Network (n = 249), the latter two of which were processed using an identical pipeline. We assessed inter- and intra-individual model performance in each dataset separately and further identified the most likely subject-specific epicentre of amyloid-beta spread. Using epicentres defined in previous work in sporadic Alzheimer's disease, the epidemic spreading model provided moderate prediction of the regional pattern of amyloid-beta deposition across all three datasets. We further find that, whilst the most likely epicentre for most amyloid-beta-positive subjects overlaps with the default mode network, 13% of autosomal-dominant Alzheimer's disease individuals were best characterized by a striatal origin of amyloid-beta spread. These subjects were also distinguished by being younger than autosomal-dominant Alzheimer's disease subjects with a default mode network amyloid-beta origin, despite having a similar estimated age of symptom onset. Together, our results suggest that most autosomal-dominant Alzheimer's disease patients express amyloid-beta spreading patterns similar to those of sporadic Alzheimer's disease, but that there may be a subset of autosomal-dominant Alzheimer's disease patients with a separate, striatal phenotype.
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Affiliation(s)
- Elizabeth Levitis
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada,Correspondence to: Elizabeth Levitis Magnuson Clinical Center Room 4N244, MSC 1367 Bethesda, MD 20814, USA E-mail:
| | - Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Thomas Funck
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | | | - Serge Gauthier
- McGill Centre for Studies in Aging, McGill University, Montreal, QC, Canada
| | - Jonathan Vöglein
- German Center for Neurodegenerative Diseases, Munich, Germany,Department of Neurology, Ludwig-Maximilians-Universität München, Munich, Germany,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Johannes Levin
- German Center for Neurodegenerative Diseases, Munich, Germany
| | - Brian A Gordon
- Department of Radiology, Washington University School of Medicine in Saint Louis, St Louis, Missouri, USA
| | - Tammie Benzinger
- Department of Radiology, Washington University School of Medicine in Saint Louis, St Louis, Missouri, USA
| | - Yasser Iturria-Medina
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada,Correspondence may also be addressed to: Alan C. Evans Montreal Neurological Institute Montreal, H3A 2B4, Quebec Canada E-mail:
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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15
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Savard M, Pascoal TA, Servaes S, Dhollander T, Iturria-Medina Y, Kang MS, Vitali P, Therriault J, Mathotaarachchi S, Benedet AL, Gauthier S, Rosa-Neto P. Impact of long- and short-range fiber depletion on the cognitive deficits of fronto-temporal dementia. eLife 2022; 11:73510. [PMID: 35073256 PMCID: PMC8824472 DOI: 10.7554/elife.73510] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 01/23/2022] [Indexed: 11/21/2022] Open
Abstract
Recent studies suggest a framework where white-matter (WM) atrophy plays an important role in fronto-temporal dementia (FTD) pathophysiology. However, these studies often overlook the fact that WM tracts bridging different brain regions may have different vulnerabilities to the disease and the relative contribution of grey-matter (GM) atrophy to this WM model, resulting in a less comprehensive understanding of the relationship between clinical symptoms and pathology. Using a common factor analysis to extract a semantic and an executive factor, we aimed to test the relative contribution of WM and GM of specific tracts in predicting cognition in the Frontotemporal Lobar Degeneration Neuroimaging Initiative (FTLDNI). We found that semantic symptoms were mainly dependent on short-range WM fibre disruption, while damage to long-range WM fibres was preferentially associated to executive dysfunction with the GM contribution to cognition being predominant for local processing. These results support the importance of the disruption of specific WM tracts to the core cognitive symptoms associated with FTD. As large-scale WM tracts, which are particularly vulnerable to vascular disease, were highly associated with executive dysfunction, our findings highlight the importance of controlling for risk factors associated with deep WM disease, such as vascular risk factors, in patients with FTD in order not to potentiate underlying executive dysfunction.
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Affiliation(s)
- Melissa Savard
- Translational Neuroimaging Laboratory, McGill University
| | | | - Stijn Servaes
- Translational Neuroimaging Laboratory, McGill University
| | | | | | - Min Su Kang
- Translational Neuroimaging Laboratory, McGill University
| | - Paolo Vitali
- Department of Neurology and Neurosurgery, McGill University
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16
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Khan AF, Adewale Q, Baumeister TR, Carbonell F, Zilles K, Palomero-Gallagher N, Iturria-Medina Y. Personalized brain models identify neurotransmitter receptor changes in Alzheimer's disease. Brain 2021; 145:1785-1804. [PMID: 34605898 DOI: 10.1093/brain/awab375] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 11/12/2022] Open
Abstract
Alzheimer's disease (AD) involves many neurobiological alterations from molecular to macroscopic spatial scales, but we currently lack integrative, mechanistic brain models characterizing how factors across different biological scales interact to cause clinical deterioration in a way that is subject-specific or personalized. Neurotransmitter receptors, as important signaling molecules and potential drug targets, are key mediators of interactions between many neurobiological processes altered in AD. We present a neurotransmitter receptor-enriched multifactorial brain model, which integrates spatial distribution patterns of 15 neurotransmitter receptors from post-mortem autoradiography with multiple in-vivo neuroimaging modalities (tau, amyloid-β and glucose PET, and structural, functional and arterial spin labeling MRI) in a personalized, generative, whole-brain formulation. Applying this data-driven model to a heterogeneous aged population (N = 423, ADNI data), we observed that personalized receptor-neuroimaging interactions explained about 70% (± 20%) of the across-population variance in longitudinal changes to the six neuroimaging modalities, and up to 39.7% (P < 0.003, FWE-corrected) of inter-individual variability in AD cognitive deterioration via an axis primarily affecting executive function. Notably, based on their contribution to the clinical severity in AD, we found significant functional alterations to glutamatergic interactions affecting tau accumulation and neural activity dysfunction, and GABAergic interactions concurrently affecting neural activity dysfunction, amyloid and tau distributions, as well as significant cholinergic receptor effects on tau accumulation. Overall, GABAergic alterations had the largest effect on cognitive impairment (particularly executive function) in our AD cohort (N = 25). Furthermore, we demonstrate the clinical applicability of this approach by characterizing subjects based on individualized 'fingerprints' of receptor alterations. This study introduces the first robust, data-driven framework for integrating several neurotransmitter receptors, multi-modal neuroimaging and clinical data in a flexible and interpretable brain model. It enables further understanding of the mechanistic neuropathological basis of neurodegenerative progression and heterogeneity, and constitutes a promising step towards implementing personalized, neurotransmitter-based treatments.
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Affiliation(s)
- Ahmed Faraz Khan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Canada H3A 2B4.,McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada H3A 2B4.,Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada H3A 2B4
| | - Quadri Adewale
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Canada H3A 2B4.,McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada H3A 2B4.,Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada H3A 2B4
| | - Tobias R Baumeister
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Canada H3A 2B4.,McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada H3A 2B4.,Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada H3A 2B4
| | | | - Karl Zilles
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, 52425 Jülich, Germany
| | - Nicola Palomero-Gallagher
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, 52425 Jülich, Germany.,Cécile and Oskar Vogt Institute of Brain Research, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany.,Department of Psychiatry, Psychotherapy, and Psychosomatics, Medical Faculty, RWTH Aachen, 52074 Aachen, Germany.,JARA, Translational Brain Medicine, 52074 Aachen, Germany
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Canada H3A 2B4.,McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada H3A 2B4.,Ludmer Centre for Neuroinformatics & Mental Health, Montreal, Canada H3A 2B4
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17
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Zeiler FA, Iturria-Medina Y, Thelin EP, Gomez A, Shankar JJ, Ko JH, Figley CR, Wright GEB, Anderson CM. Integrative Neuroinformatics for Precision Prognostication and Personalized Therapeutics in Moderate and Severe Traumatic Brain Injury. Front Neurol 2021; 12:729184. [PMID: 34557154 PMCID: PMC8452858 DOI: 10.3389/fneur.2021.729184] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/09/2021] [Indexed: 01/13/2023] Open
Abstract
Despite changes in guideline-based management of moderate/severe traumatic brain injury (TBI) over the preceding decades, little impact on mortality and morbidity have been seen. This argues against the “one-treatment fits all” approach to such management strategies. With this, some preliminary advances in the area of personalized medicine in TBI care have displayed promising results. However, to continue transitioning toward individually-tailored care, we require integration of complex “-omics” data sets. The past few decades have seen dramatic increases in the volume of complex multi-modal data in moderate and severe TBI care. Such data includes serial high-fidelity multi-modal characterization of the cerebral physiome, serum/cerebrospinal fluid proteomics, admission genetic profiles, and serial advanced neuroimaging modalities. Integrating these complex and serially obtained data sets, with patient baseline demographics, treatment information and clinical outcomes over time, can be a daunting task for the treating clinician. Within this review, we highlight the current status of such multi-modal omics data sets in moderate/severe TBI, current limitations to the utilization of such data, and a potential path forward through employing integrative neuroinformatic approaches, which are applied in other neuropathologies. Such advances are positioned to facilitate the transition to precision prognostication and inform a top-down approach to the development of personalized therapeutics in moderate/severe TBI.
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Affiliation(s)
- Frederick A Zeiler
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Biomedical Engineering, Faculty of Engineering, University of Manitoba, Winnipeg, MB, Canada.,Centre on Aging, University of Manitoba, Winnipeg, MB, Canada.,Division of Anaesthesia, Department of Medicine, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, Faculty of Medicine, McGill University, Montreal, QC, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada.,Ludmer Centre for Neuroinformatics and Mental Health, Montreal, QC, Canada
| | - Eric P Thelin
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Alwyn Gomez
- Section of Neurosurgery, Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Jai J Shankar
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Ji Hyun Ko
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Neuroscience Research Program, Kleysen Institute for Advanced Medicine, Winnipeg, MB, Canada
| | - Chase R Figley
- Department of Radiology, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.,Neuroscience Research Program, Kleysen Institute for Advanced Medicine, Winnipeg, MB, Canada
| | - Galen E B Wright
- Neuroscience Research Program, Kleysen Institute for Advanced Medicine, Winnipeg, MB, Canada.,Department of Pharmacology and Therapeutics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Chris M Anderson
- Neuroscience Research Program, Kleysen Institute for Advanced Medicine, Winnipeg, MB, Canada.,Department of Pharmacology and Therapeutics, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
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18
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Vogel JW, Iturria-Medina Y, Strandberg OT, Smith R, Levitis E, Evans AC, Hansson O. Author Correction: Spread of pathological tau proteins through communicating neurons in human Alzheimer's disease. Nat Commun 2021; 12:4862. [PMID: 34354079 PMCID: PMC8342451 DOI: 10.1038/s41467-021-25193-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | | | | | - Ruben Smith
- Clinical Memory Research Unit, Lund University, Lund, Sweden
- Memory Clinic, Skåne University Hospital, Lund, Sweden
| | - Elizabeth Levitis
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Oskar Hansson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.
- Memory Clinic, Skåne University Hospital, Lund, Sweden.
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19
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Tremblay-Mercier J, Madjar C, Das S, Pichet Binette A, Dyke SOM, Étienne P, Lafaille-Magnan ME, Remz J, Bellec P, Louis Collins D, Natasha Rajah M, Bohbot V, Leoutsakos JM, Iturria-Medina Y, Kat J, Hoge RD, Gauthier S, Tardif CL, Mallar Chakravarty M, Poline JB, Rosa-Neto P, Evans AC, Villeneuve S, Poirier J, Breitner JCS. Open science datasets from PREVENT-AD, a longitudinal cohort of pre-symptomatic Alzheimer's disease. Neuroimage Clin 2021; 31:102733. [PMID: 34192666 PMCID: PMC8254111 DOI: 10.1016/j.nicl.2021.102733] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 02/07/2023]
Abstract
To move Alzheimer Disease (AD) research forward it is essential to collect data from large cohorts, but also make such data available to the global research community. We describe the creation of an open science dataset from the PREVENT-AD (PResymptomatic EValuation of Experimental or Novel Treatments for AD) cohort, composed of cognitively unimpaired older individuals with a parental or multiple-sibling history of AD. From 2011 to 2017, 386 participants were enrolled (mean age 63 years old ± 5) for sustained investigation among whom 349 have retrospectively agreed to share their data openly. Repositories are findable through the unified interface of the Canadian Open Neuroscience Platform and contain up to five years of longitudinal imaging data, cerebral fluid biochemistry, neurosensory capacities, cognitive, genetic, and medical information. Imaging data can be accessed openly at https://openpreventad.loris.ca while most of the other information, sensitive by nature, is accessible by qualified researchers at https://registeredpreventad.loris.ca. In addition to being a living resource for continued data acquisition, PREVENT-AD offers opportunities to facilitate understanding of AD pathogenesis.
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Affiliation(s)
| | - Cécile Madjar
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Samir Das
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Alexa Pichet Binette
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | - Stephanie O M Dyke
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Pierre Étienne
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | - Marie-Elyse Lafaille-Magnan
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; Centre for Child Development and Mental Health, Jewish General Hospital. Montréal, QC, Canada.
| | - Jordana Remz
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada.
| | - Pierre Bellec
- CRIUGM - Université de Montréal, Montréal, QC, Canada; Université de Montréal, Montréal, QC, Canada.
| | - D Louis Collins
- McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - M Natasha Rajah
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | - Veronique Bohbot
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | | | - Yasser Iturria-Medina
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Justin Kat
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Richard D Hoge
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; Université de Montréal, Montréal, QC, Canada.
| | - Serge Gauthier
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McGill University Research Centre for Studies in Aging, McGill University, Montréal, QC, Canada.
| | - Christine L Tardif
- McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - M Mallar Chakravarty
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | - Jean-Baptiste Poline
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Pedro Rosa-Neto
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University Research Centre for Studies in Aging, McGill University, Montréal, QC, Canada.
| | - Alan C Evans
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Sylvia Villeneuve
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montréal, QC, Canada; McGill University, Montréal, QC, Canada; McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Judes Poirier
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
| | - John C S Breitner
- StoP-AD Centre, Douglas Mental Health Institute Research Centre, Montréal, QC, Canada; McGill University, Montréal, QC, Canada.
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20
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Adewale Q, Khan AF, Carbonell F, Iturria-Medina Y. Integrated transcriptomic and neuroimaging brain model decodes biological mechanisms in aging and Alzheimer's disease. eLife 2021; 10:e62589. [PMID: 34002691 PMCID: PMC8131100 DOI: 10.7554/elife.62589] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 03/24/2021] [Indexed: 02/07/2023] Open
Abstract
Both healthy aging and Alzheimer's disease (AD) are characterized by concurrent alterations in several biological factors. However, generative brain models of aging and AD are limited in incorporating the measures of these biological factors at different spatial resolutions. Here, we propose a personalized bottom-up spatiotemporal brain model that accounts for the direct interplay between hundreds of RNA transcripts and multiple macroscopic neuroimaging modalities (PET, MRI). In normal elderly and AD participants, the model identifies top genes modulating tau and amyloid-β burdens, vascular flow, glucose metabolism, functional activity, and atrophy to drive cognitive decline. The results also revealed that AD and healthy aging share specific biological mechanisms, even though AD is a separate entity with considerably more altered pathways. Overall, this personalized model offers novel insights into the multiscale alterations in the elderly brain, with important implications for identifying effective genetic targets for extending healthy aging and treating AD progression.
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Affiliation(s)
- Quadri Adewale
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill UniversityMontrealCanada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill UniversityMontrealCanada
| | - Ahmed F Khan
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill UniversityMontrealCanada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill UniversityMontrealCanada
| | | | - Yasser Iturria-Medina
- Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill UniversityMontrealCanada
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill UniversityMontrealCanada
- Ludmer Centre for Neuroinformatics and Mental Health, McGill UniversityMontrealCanada
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21
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Vogel JW, Young AL, Oxtoby NP, Smith R, Ossenkoppele R, Strandberg OT, La Joie R, Aksman LM, Grothe MJ, Iturria-Medina Y, Pontecorvo MJ, Devous MD, Rabinovici GD, Alexander DC, Lyoo CH, Evans AC, Hansson O. Four distinct trajectories of tau deposition identified in Alzheimer's disease. Nat Med 2021; 27:871-881. [PMID: 33927414 PMCID: PMC8686688 DOI: 10.1038/s41591-021-01309-6] [Citation(s) in RCA: 290] [Impact Index Per Article: 96.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 03/04/2021] [Indexed: 01/15/2023]
Abstract
Alzheimer's disease (AD) is characterized by the spread of tau pathology throughout the cerebral cortex. This spreading pattern was thought to be fairly consistent across individuals, although recent work has demonstrated substantial variability in the population with AD. Using tau-positron emission tomography scans from 1,612 individuals, we identified 4 distinct spatiotemporal trajectories of tau pathology, ranging in prevalence from 18 to 33%. We replicated previously described limbic-predominant and medial temporal lobe-sparing patterns, while also discovering posterior and lateral temporal patterns resembling atypical clinical variants of AD. These 'subtypes' were stable during longitudinal follow-up and were replicated in a separate sample using a different radiotracer. The subtypes presented with distinct demographic and cognitive profiles and differing longitudinal outcomes. Additionally, network diffusion models implied that pathology originates and spreads through distinct corticolimbic networks in the different subtypes. Together, our results suggest that variation in tau pathology is common and systematic, perhaps warranting a re-examination of the notion of 'typical AD' and a revisiting of tau pathological staging.
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Affiliation(s)
- Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada.
| | - Alexandra L Young
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Neil P Oxtoby
- Centre for Medical Image Computing, University College London, London, UK
- Department of Computer Science, University College London, London, UK
| | - Ruben Smith
- Clinical Memory Research Unit, Lund University, Lund, Sweden
- Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Rik Ossenkoppele
- Clinical Memory Research Unit, Lund University, Lund, Sweden
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | | | - Renaud La Joie
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Leon M Aksman
- Centre for Medical Image Computing, University College London, London, UK
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Michel J Grothe
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, Seville, Spain
| | | | | | | | - Gil D Rabinovici
- Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Daniel C Alexander
- Centre for Medical Image Computing, University College London, London, UK
- Department of Computer Science, University College London, London, UK
| | - Chul Hyoung Lyoo
- Departments of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada
| | - Oskar Hansson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.
- Memory Clinic, Skåne University Hospital, Malmö, Sweden.
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22
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Santonja J, Martínez K, Román FJ, Escorial S, Quiroga MÁ, Álvarez-Linera J, Iturria-Medina Y, Santarnecchi E, Colom R. Brain resilience across the general cognitive ability distribution: Evidence from structural connectivity. Brain Struct Funct 2021; 226:845-859. [DOI: 10.1007/s00429-020-02213-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 12/30/2020] [Indexed: 12/14/2022]
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23
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Zayed A, Iturria-Medina Y, Villringer A, Sehm B, Steele CJ. Rapid Quantification of White Matter Disconnection in the Human Brain. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2020:1701-1704. [PMID: 33018324 DOI: 10.1109/embc44109.2020.9176229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
With an estimated five million new stroke survivors every year and a rapidly aging population suffering from hyperintensities and diseases of presumed vascular origin that affect white matter and contribute to cognitive decline, it is critical that we understand the impact of white matter damage on brain structure and behavior. Current techniques for assessing the impact of lesions consider only location, type, and extent, while ignoring how the affected region was connected to the rest of the brain. Regional brain function is a product of both local structure and its connectivity. Therefore, obtaining a map of white matter disconnection is a crucial step that could help us predict the behavioral deficits that patients exhibit. In the present work, we introduce a new practical method for computing lesion-based white matter disconnection maps that require only moderate computational resources. We achieve this by creating diffusion tractography models of the brains of healthy adults and assessing the connectivity between small regions. We then interrupt these connectivity models by projecting patients' lesions into them to compute predicted white matter disconnection. A quantified disconnection map can be computed for an individual patient in approximately 35 seconds using a single core CPU-based computation. In comparison, a similar quantification performed with other tools provided by MRtrix3 takes 5.47 minutes.
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24
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Sanchez-Rodriguez LM, Iturria-Medina Y, Mouches P, Sotero RC. Detecting brain network communities: Considering the role of information flow and its different temporal scales. Neuroimage 2020; 225:117431. [PMID: 33045336 DOI: 10.1016/j.neuroimage.2020.117431] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 09/22/2020] [Accepted: 09/29/2020] [Indexed: 12/16/2022] Open
Abstract
The identification of community structure in graphs continues to attract great interest in several fields. Network neuroscience is particularly concerned with this problem considering the key roles communities play in brain processes and functionality. Most methods used for community detection in brain graphs are based on the maximization of a parameter-dependent modularity function that often obscures the physical meaning and hierarchical organization of the partitions of network nodes. In this work, we present a new method able to detect communities at different scales in a natural, unrestricted way. First, to obtain an estimation of the information flow in the network we release random walkers to freely move over it. The activity of the walkers is separated into oscillatory modes by using empirical mode decomposition. After grouping nodes by their co-occurrence at each time scale, k-modes clustering returns the desired partitions. Our algorithm was first tested on benchmark graphs with favorable performance. Next, it was applied to real and simulated anatomical and/or functional connectomes in the macaque and human brains. We found a clear hierarchical repertoire of community structures in both the anatomical and the functional networks. The observed partitions range from the evident division in two hemispheres -in which all processes are managed globally- to specialized communities seemingly shaped by physical proximity and shared function. Additionally, the spatial scales of a network's community structure (characterized by a measure we term within-communities path length) appear inversely proportional to the oscillatory modes' average frequencies. The proportionality constant may constitute a network-specific propagation velocity for the information flow. Our results stimulate the research of hierarchical community organization in terms of temporal scales of information flow in the brain network.
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Affiliation(s)
- Lazaro M Sanchez-Rodriguez
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill Univ., Montreal, Canada; McConnel Brain Imaging Center, Montreal Neurological Institute, McGill Univ., Montreal, Canada; Ludmer Centre for Neuroinformatics and Mental Health, McGill Univ., Montreal, Canada.
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill Univ., Montreal, Canada; McConnel Brain Imaging Center, Montreal Neurological Institute, McGill Univ., Montreal, Canada; Ludmer Centre for Neuroinformatics and Mental Health, McGill Univ., Montreal, Canada
| | - Pauline Mouches
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
| | - Roberto C Sotero
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada.
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25
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Hachinski V, Einhäupl K, Ganten D, Alladi S, Brayne C, Stephan BCM, Sweeney MD, Zlokovic B, Iturria-Medina Y, Iadecola C, Nishimura N, Schaffer CB, Whitehead SN, Black SE, Østergaard L, Wardlaw J, Greenberg S, Friberg L, Norrving B, Rowe B, Joanette Y, Hacke W, Kuller L, Dichgans M, Endres M, Khachaturian ZS. Preventing dementia by preventing stroke: The Berlin Manifesto. Alzheimers Dement 2020; 15:961-984. [PMID: 31327392 DOI: 10.1016/j.jalz.2019.06.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The incidence of stroke and dementia are diverging across the world, rising for those in low- and middle-income countries and falling in those in high-income countries. This suggests that whatever factors cause these trends are potentially modifiable. At the population level, neurological disorders as a group account for the largest proportion of disability-adjusted life years globally (10%). Among neurological disorders, stroke (42%) and dementia (10%) dominate. Stroke and dementia confer risks for each other and share some of the same, largely modifiable, risk and protective factors. In principle, 90% of strokes and 35% of dementias have been estimated to be preventable. Because a stroke doubles the chance of developing dementia and stroke is more common than dementia, more than a third of dementias could be prevented by preventing stroke. Developments at the pathological, pathophysiological, and clinical level also point to new directions. Growing understanding of brain pathophysiology has unveiled the reciprocal interaction of cerebrovascular disease and neurodegeneration identifying new therapeutic targets to include protection of the endothelium, the blood-brain barrier, and other components of the neurovascular unit. In addition, targeting amyloid angiopathy aspects of inflammation and genetic manipulation hold new testable promise. In the meantime, accumulating evidence suggests that whole populations experiencing improved education, and lower vascular risk factor profiles (e.g., reduced prevalence of smoking) and vascular disease, including stroke, have better cognitive function and lower dementia rates. At the individual levels, trials have demonstrated that anticoagulation of atrial fibrillation can reduce the risk of dementia by 48% and that systolic blood pressure lower than 140 mmHg may be better for the brain. Based on these considerations, the World Stroke Organization has issued a proclamation, endorsed by all the major international organizations focused on global brain and cardiovascular health, calling for the joint prevention of stroke and dementia. This article summarizes the evidence for translation into action.
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Affiliation(s)
- Vladimir Hachinski
- Department of Clinical Neurological Sciences, Western University, Ontario, Canada.
| | - Karl Einhäupl
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Detlev Ganten
- Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Suvarna Alladi
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| | - Carol Brayne
- Department of Public Health and Primary Care in the University of Cambridge, Cambridge, UK
| | - Blossom C M Stephan
- Institute of Mental Health, Division of Psychiatry and Applied Psychology, School of Medicine, University of Nottingham, Nottingham, UK
| | - Melanie D Sweeney
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Berislav Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Nozomi Nishimura
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Chris B Schaffer
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Shawn N Whitehead
- Department of Anatomy and Cell Biology, Western University, Ontario, Canada
| | - Sandra E Black
- Department of Medicine (Neurology), Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Leif Østergaard
- Department of Clinical Medicine, Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark; Department of Neuroradiology, Aarhus University Hospital, Aarhus, Denmark
| | - Joanna Wardlaw
- Centre for Clinical Brain Sciences, Edinburgh Imaging, UK Dementia Research Institute, University of Edinburgh, Scotland, UK
| | - Steven Greenberg
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Leif Friberg
- Department of Clinical Sciences, Karolinska Institute, Stockholm, Sweden
| | - Bo Norrving
- Department of Clinical Sciences, Neurology, Lund University, Lund, Sweden
| | - Brian Rowe
- Department of Emergency Medicine and School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Yves Joanette
- Canadian Institute of Health and Research, Ottawa, Canada
| | - Werner Hacke
- Department of Neurology, Heidelberg University, Heidelberg, Germany
| | - Lewis Kuller
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Martin Dichgans
- Institute for Stroke and Dementia Research (ISD), University Hospital, Ludwig-Maximilians-Universität LMU, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany; German Center for Neurodegenerative Diseases (DZNE, Munich), Munich, Germany
| | - Matthias Endres
- Department of Neurology with Experimental Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany; Center for Stroke Research Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany; ExcellenceCluster NeuroCure, Charité-Universitätsmedizin Berlin, Berlin, Germany; German Center for Neurodegenerative Diseases (DZNE), partner site Berlin, Berlin, Germany; German Centre for Cardiovascular Research (DZHK), partner site Berlin, Berlin, Germany; Berlin Institute of Health (BIH), Berlin, Germany
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26
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Iturria-Medina Y, Khan AF, Adewale Q, Shirazi AH. Blood and brain gene expression trajectories mirror neuropathology and clinical deterioration in neurodegeneration. Brain 2020; 143:661-673. [PMID: 31989163 DOI: 10.1093/brain/awz400] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 10/05/2019] [Accepted: 11/04/2019] [Indexed: 12/28/2022] Open
Abstract
Most prevalent neurodegenerative disorders take decades to develop and their early detection is challenged by confounding non-pathological ageing processes. For all neurodegenerative conditions, we continue to lack longitudinal gene expression data covering their large temporal evolution, which hinders the understanding of the underlying dynamic molecular mechanisms. Here, we overcome this key limitation by introducing a novel gene expression contrastive trajectory inference (GE-cTI) method that reveals enriched temporal patterns in a diseased population. Evaluated on 1969 subjects in the spectrum of late-onset Alzheimer's and Huntington's diseases (from ROSMAP, HBTRC and ADNI datasets), this unsupervised machine learning algorithm strongly predicts neuropathological severity (e.g. Braak, amyloid and Vonsattel stages). Furthermore, when applied to in vivo blood samples at baseline (ADNI), it significantly predicts clinical deterioration and conversion to advanced disease stages, supporting the identification of a minimally invasive (blood-based) tool for early clinical screening. This technique also allows the discovery of genes and molecular pathways, in both peripheral and brain tissues, that are highly predictive of disease evolution. Eighty-five to ninety per cent of the most predictive molecular pathways identified in the brain are also top predictors in the blood. These pathways support the importance of studying the peripheral-brain axis, providing further evidence for a key role of vascular structure/functioning and immune system response. The GE-cTI is a promising tool for revealing complex neuropathological mechanisms, with direct implications for implementing personalized dynamic treatments in neurology.
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Affiliation(s)
- Yasser Iturria-Medina
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada.,Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada
| | - Ahmed F Khan
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada.,Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada
| | - Quadri Adewale
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada.,Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada
| | - Amir H Shirazi
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada.,Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada
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27
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Vogel JW, Iturria-Medina Y, Strandberg OT, Smith R, Levitis E, Evans AC, Hansson O. Spread of pathological tau proteins through communicating neurons in human Alzheimer's disease. Nat Commun 2020; 11:2612. [PMID: 32457389 PMCID: PMC7251068 DOI: 10.1038/s41467-020-15701-2] [Citation(s) in RCA: 231] [Impact Index Per Article: 57.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 03/06/2020] [Indexed: 02/07/2023] Open
Abstract
Tau is a hallmark pathology of Alzheimer's disease, and animal models have suggested that tau spreads from cell to cell through neuronal connections, facilitated by β-amyloid (Aβ). We test this hypothesis in humans using an epidemic spreading model (ESM) to simulate tau spread, and compare these simulations to observed patterns measured using tau-PET in 312 individuals along Alzheimer's disease continuum. Up to 70% of the variance in the overall spatial pattern of tau can be explained by our model. Surprisingly, the ESM predicts the spatial patterns of tau irrespective of whether brain Aβ is present, but regions with greater Aβ burden show greater tau than predicted by connectivity patterns, suggesting a role of Aβ in accelerating tau spread. Altogether, our results provide evidence in humans that tau spreads through neuronal communication pathways even in normal aging, and that this process is accelerated by the presence of brain Aβ.
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Affiliation(s)
- Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | | | | | - Ruben Smith
- Clinical Memory Research Unit, Lund University, Lund, Sweden
- Memory Clinic, Skåne University Hospital, Lund, Sweden
| | - Elizabeth Levitis
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Oskar Hansson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.
- Memory Clinic, Skåne University Hospital, Lund, Sweden.
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28
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Vogel JW, La Joie R, Grothe MJ, Diaz-Papkovich A, Doyle A, Vachon-Presseau E, Lepage C, Vos de Wael R, Thomas RA, Iturria-Medina Y, Bernhardt B, Rabinovici GD, Evans AC. A molecular gradient along the longitudinal axis of the human hippocampus informs large-scale behavioral systems. Nat Commun 2020; 11:960. [PMID: 32075960 PMCID: PMC7031290 DOI: 10.1038/s41467-020-14518-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 12/09/2019] [Indexed: 12/20/2022] Open
Abstract
The functional organization of the hippocampus is distributed as a gradient along its longitudinal axis that explains its differential interaction with diverse brain systems. We show that the location of human tissue samples extracted along the longitudinal axis of the adult human hippocampus can be predicted within 2mm using the expression pattern of less than 100 genes. Futhermore, this model generalizes to an external set of tissue samples from prenatal human hippocampi. We examine variation in this specific gene expression pattern across the whole brain, finding a distinct anterioventral-posteriodorsal gradient. We find frontal and anterior temporal regions involved in social and motivational behaviors, and more functionally connected to the anterior hippocampus, to be clearly differentiated from posterior parieto-occipital regions involved in visuospatial cognition and more functionally connected to the posterior hippocampus. These findings place the human hippocampus at the interface of two major brain systems defined by a single molecular gradient.
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Affiliation(s)
- Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
| | - Renaud La Joie
- Memory and Aging Center, University of California, San Francisco, CA, USA
| | - Michel J Grothe
- German Center for Neurodegenerative Diseases (DZNE), Rostock, Germany
| | - Alexandr Diaz-Papkovich
- McGill University and Genome Quebec Innovation Centre, Montréal, QC, Canada
- Quantitative Life Sciences, McGill University, Montreal, QC, H3A 0G1, Canada
| | - Andrew Doyle
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Etienne Vachon-Presseau
- Faculty of Dentistry, Department of Anesthesia, McGill University, Montréal, QC, Canada
- Alan Edwards Centre for Research on Pain (AECRP), McGill University, Montréal, QC, Canada
| | - Claude Lepage
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | | | - Rhalena A Thomas
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | | | - Boris Bernhardt
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Gil D Rabinovici
- Memory and Aging Center, University of California, San Francisco, CA, USA
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
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29
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Hachinski V, Einhäupl K, Ganten D, Alladi S, Brayne C, Stephan BCM, Sweeney MD, Zlokovic B, Iturria-Medina Y, Iadecola C, Nishimura N, Schaffer CB, Whitehead SN, Black SE, Østergaard L, Wardlaw J, Greenberg S, Friberg L, Norrving B, Rowe B, Joanette Y, Hacke W, Kuller L, Dichgans M, Endres M, Khachaturian ZS. Special topic section: linkages among cerebrovascular, cardiovascular, and cognitive disorders: Preventing dementia by preventing stroke: The Berlin Manifesto. Int J Stroke 2019:1747493019871915. [PMID: 31543058 DOI: 10.1177/1747493019871915] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
The incidence of stroke and dementia are diverging across the world, rising for those in low-and middle-income countries and falling in those in high-income countries. This suggests that whatever factors cause these trends are potentially modifiable. At the population level, neurological disorders as a group account for the largest proportion of disability-adjusted life years globally (10%). Among neurological disorders, stroke (42%) and dementia (10%) dominate. Stroke and dementia confer risks for each other and share some of the same, largely modifiable, risk and protective factors. In principle, 90% of strokes and 35% of dementias have been estimated to be preventable. Because a stroke doubles the chance of developing dementia and stroke is more common than dementia, more than a third of dementias could be prevented by preventing stroke. Developments at the pathological, pathophysiological, and clinical level also point to new directions. Growing understanding of brain pathophysiology has unveiled the reciprocal interaction of cerebrovascular disease and neurodegeneration identifying new therapeutic targets to include protection of the endothelium, the blood-brain barrier, and other components of the neurovascular unit. In addition, targeting amyloid angiopathy aspects of inflammation and genetic manipulation hold new testable promise. In the meantime, accumulating evidence suggests that whole populations experiencing improved education, and lower vascular risk factor profiles (e.g., reduced prevalence of smoking) and vascular disease, including stroke, have better cognitive function and lower dementia rates. At the individual levels, trials have demonstrated that anticoagulation of atrial fibrillation can reduce the risk of dementia by 48% and that systolic blood pressure lower than 140 mmHg may be better for the brain. Based on these considerations, the World Stroke Organization has issued a proclamation, endorsed by all the major international organizations focused on global brain and cardiovascular health, calling for the joint prevention of stroke and dementia. This article summarizes the evidence for translation into action. © 2019 the Alzheimer's Association and the World Stroke Organisation. Published by Elsevier Inc. All rights reserved.
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Affiliation(s)
- Vladimir Hachinski
- Department of Clinical Neurological Sciences, Western University, Ontario, Canada
| | - Karl Einhäupl
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Detlev Ganten
- Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Suvarna Alladi
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bengaluru, Karnataka, India
| | - Carol Brayne
- Department of Public Health and Primary Care in the University of Cambridge, Cambridge, UK
| | - Blossom C M Stephan
- Institute of Mental Health, Division of Psychiatry and Applied Psychology, School of Medicine, University of Nottingham, Nottingham, UK
| | - Melanie D Sweeney
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Berislav Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yasser Iturria-Medina
- Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Nozomi Nishimura
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Chris B Schaffer
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Shawn N Whitehead
- Department of Anatomy and Cell Biology, Western University, Ontario, Canada
| | - Sandra E Black
- Department of Medicine (Neurology), Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Leif Østergaard
- Department of Clinical Medicine, Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark
- Department of Neuroradiology, Aarhus University Hospital, Aarhus, Denmark
| | - Joanna Wardlaw
- Centre for Clinical Brain Sciences, Edinburgh Imaging, UK Dementia Research Institute, University of Edinburgh, Scotland, UK
| | - Steven Greenberg
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Leif Friberg
- Department of Clinical Sciences, Karolinska Institute, Stockholm, Sweden
| | - Bo Norrving
- Department of Clinical Sciences, Neurology, Lund University, Lund, Sweden
| | - Brian Rowe
- Department of Emergency Medicine and School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Yves Joanette
- Canadian Institute of Health and Research, Ottawa, Canada
| | - Werner Hacke
- Department of Neurology, Heidelberg University, Heidelberg, Germany
| | - Lewis Kuller
- Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Martin Dichgans
- Institute for Stroke and Dementia Research (ISD), University Hospital, Ludwig-Maximilians-Universität LMU, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE, Munich), Munich, Germany
| | - Matthias Endres
- Department of Neurology with Experimental Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Center for Stroke Research Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany
- ExcellenceCluster NeuroCure, Charité-Universitätsmedizin Berlin, Berlin, Germany
- German Center for Neurodegenerative Diseases (DZNE), partner site Berlin, Berlin, Germany
- German Centre for Cardiovascular Research (DZHK), partner site Berlin, Berlin, Germany
- Berlin Institute of Health (BIH), Berlin, Germany
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30
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Tam A, Dansereau C, Iturria-Medina Y, Urchs S, Orban P, Sharmarke H, Breitner J, Bellec P. A highly predictive signature of cognition and brain atrophy for progression to Alzheimer's dementia. Gigascience 2019; 8:giz055. [PMID: 31077314 PMCID: PMC6511068 DOI: 10.1093/gigascience/giz055] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 03/07/2019] [Accepted: 04/21/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Clinical trials in Alzheimer's disease need to enroll patients whose cognition will decline over time, if left untreated, in order to demonstrate the efficacy of an intervention. Machine learning models used to screen for patients at risk of progression to dementia should therefore favor specificity (detecting only progressors) over sensitivity (detecting all progressors), especially when the prevalence of progressors is low. Here, we explore whether such high-risk patients can be identified using cognitive assessments and structural neuroimaging by training machine learning tools in a high-specificity regime. RESULTS A multimodal signature of Alzheimer's dementia was first extracted from the ADNI1 dataset. We then validated the predictive value of this signature on ADNI1 patients with mild cognitive impairment (N = 235). The signature was optimized to predict progression to dementia over 3 years with low sensitivity (55.1%) but high specificity (95.6%), resulting in only moderate accuracy (69.3%) but high positive predictive value (80.4%, adjusted for a "typical" 33% prevalence rate of true progressors). These results were replicated in ADNI2 (N = 235), with 87.8% adjusted positive predictive value (96.7% specificity, 47.3% sensitivity, 85.1% accuracy). CONCLUSIONS We found that cognitive measures alone could identify high-risk individuals, with structural measurements providing a slight improvement. The signature had comparable receiver operating characteristics to standard machine learning tools, yet a marked improvement in positive predictive value was achieved over the literature by selecting a high-specificity operating point. The multimodal signature can be readily applied for the enrichment of clinical trials.
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Affiliation(s)
- Angela Tam
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
- Centre for the Studies on Prevention of Alzheimer's Disease, Douglas Mental Health University Institute Research Centre, 6875 Lasalle Boulevard, Montréal, QC, H4H 1R3, Canada
| | - Christian Dansereau
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
- Département d'informatique et de recherche opérationnelle, Université de Montréal, 2920 chemin de la Tour, Montréal, QC, H3T 1J4, Canada
| | - Yasser Iturria-Medina
- Montreal Neurological Institute, McGill University, 3801 University Street, Montréal, QC, H3A 2B4, Canada
| | - Sebastian Urchs
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
- Montreal Neurological Institute, McGill University, 3801 University Street, Montréal, QC, H3A 2B4, Canada
| | - Pierre Orban
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
- Centre de Recherche de l'Institut Universitaire en Santé Mentale de Montréal, 7331 rue Hochelaga, Montréal, QC, H1N 3V2, Canada
- Département de psychiatrie, Université de Montréal, 2900 boulevard Édouard-Montpetit, Montréal, QC, H3T 1J4, Canada
| | - Hanad Sharmarke
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
| | - John Breitner
- Centre for the Studies on Prevention of Alzheimer's Disease, Douglas Mental Health University Institute Research Centre, 6875 Lasalle Boulevard, Montréal, QC, H4H 1R3, Canada
- Department of Psychiatry, McGill University, 1033 Pine Avenue West, Montréal, QC, H3A 1A1, Canada
| | - Pierre Bellec
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, 4545 chemin Queen-Mary, Montréal, QC, H3W 1W4, Canada
- Département de psychologie, Université de Montréal, 90 avenue Vincent d'Indy, Montréal, QC, H3C 3J7, Canada
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31
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Affiliation(s)
- Ashish Raj
- Department of Radiology, Weill Cornell Medicine, New York, NY, United States.,Department of Radiology, University of California at San Francisco, San Francisco, CA, United States
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32
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Vogel JW, Mattsson N, Iturria-Medina Y, Strandberg OT, Schöll M, Dansereau C, Villeneuve S, van der Flier WM, Scheltens P, Bellec P, Evans AC, Hansson O, Ossenkoppele R. Data-driven approaches for tau-PET imaging biomarkers in Alzheimer's disease. Hum Brain Mapp 2018; 40:638-651. [PMID: 30368979 DOI: 10.1002/hbm.24401] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/09/2018] [Accepted: 09/04/2018] [Indexed: 12/14/2022] Open
Abstract
Previous positron emission tomography (PET) studies have quantified filamentous tau pathology using regions-of-interest (ROIs) based on observations of the topographical distribution of neurofibrillary tangles in post-mortem tissue. However, such approaches may not take full advantage of information contained in neuroimaging data. The present study employs an unsupervised data-driven method to identify spatial patterns of tau-PET distribution, and to compare these patterns to previously published "pathology-driven" ROIs. Tau-PET patterns were identified from a discovery sample comprised of 123 normal controls and patients with mild cognitive impairment or Alzheimer's disease (AD) dementia from the Swedish BioFINDER cohort, who underwent [18 F]AV1451 PET scanning. Associations with cognition were tested in a separate sample of 90 individuals from ADNI. BioFINDER [18 F]AV1451 images were entered into a robust voxelwise stable clustering algorithm, which resulted in five clusters. Mean [18 F]AV1451 uptake in the data-driven clusters, and in 35 previously published pathology-driven ROIs, was extracted from ADNI [18 F]AV1451 scans. We performed linear models comparing [18 F]AV1451 signal across all 40 ROIs to tests of global cognition and episodic memory, adjusting for age, sex, and education. Two data-driven ROIs consistently demonstrated the strongest or near-strongest effect sizes across all cognitive tests. Inputting all regions plus demographics into a feature selection routine resulted in selection of two ROIs (one data-driven, one pathology-driven) and education, which together explained 28% of the variance of a global cognitive composite score. Our findings suggest that [18 F]AV1451-PET data naturally clusters into spatial patterns that are biologically meaningful and that may offer advantages as clinical tools.
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Affiliation(s)
- Jacob W Vogel
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.,Alzheimer Center and Department of Neurology, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Niklas Mattsson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Memory Clinic, Skåne University Hospital, Lund, Sweden.,Department of Neurology, Skåne University Hospital, Lund, Sweden
| | | | | | - Michael Schöll
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Christian Dansereau
- Department of Computer Science and Operations Research, Université de Montréal, Montreal, Quebec, Canada.,Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, University of Montreal, Montreal, Quebec, Canada
| | - Sylvia Villeneuve
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.,Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Wiesje M van der Flier
- Alzheimer Center and Department of Neurology, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands.,Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, Netherlands
| | - Philip Scheltens
- Alzheimer Center and Department of Neurology, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Pierre Bellec
- Department of Computer Science and Operations Research, Université de Montréal, Montreal, Quebec, Canada.,Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal, University of Montreal, Montreal, Quebec, Canada
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Oskar Hansson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Memory Clinic, Skåne University Hospital, Lund, Sweden
| | - Rik Ossenkoppele
- Alzheimer Center and Department of Neurology, VU University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands.,Clinical Memory Research Unit, Lund University, Lund, Sweden
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33
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Mateos-Pérez JM, Dadar M, Lacalle-Aurioles M, Iturria-Medina Y, Zeighami Y, Evans AC. Structural neuroimaging as clinical predictor: A review of machine learning applications. Neuroimage Clin 2018; 20:506-522. [PMID: 30167371 PMCID: PMC6108077 DOI: 10.1016/j.nicl.2018.08.019] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 01/22/2018] [Accepted: 08/09/2018] [Indexed: 11/26/2022]
Abstract
In this paper, we provide an extensive overview of machine learning techniques applied to structural magnetic resonance imaging (MRI) data to obtain clinical classifiers. We specifically address practical problems commonly encountered in the literature, with the aim of helping researchers improve the application of these techniques in future works. Additionally, we survey how these algorithms are applied to a wide range of diseases and disorders (e.g. Alzheimer's disease (AD), Parkinson's disease (PD), autism, multiple sclerosis, traumatic brain injury, etc.) in order to provide a comprehensive view of the state of the art in different fields.
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Affiliation(s)
| | - Mahsa Dadar
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | | | | | - Yashar Zeighami
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Alan C Evans
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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34
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Iturria-Medina Y, Carbonell FM, Evans AC. Multimodal imaging-based therapeutic fingerprints for optimizing personalized interventions: Application to neurodegeneration. Neuroimage 2018; 179:40-50. [PMID: 29894824 DOI: 10.1016/j.neuroimage.2018.06.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 05/10/2018] [Accepted: 06/08/2018] [Indexed: 01/23/2023] Open
Abstract
Personalized Medicine (PM) seeks to assist the patients according to their specific treatment needs and potential intervention responses. However, in the neurological context, this approach is limited by crucial methodological challenges, such as the requirement for an understanding of the causal disease mechanisms and the inability to predict the brain's response to therapeutic interventions. Here, we introduce and validate the concept of the personalized Therapeutic Intervention Fingerprint (pTIF), which predicts the effectiveness of potential interventions for controlling a patient's disease evolution. Each subject's pTIF can be inferred from multimodal longitudinal imaging (e.g. amyloid-β, metabolic and tau PET; vascular, functional and structural MRI). We studied an aging population (N = 331) comprising cognitively normal and neurodegenerative patients, longitudinally scanned using six different neuroimaging modalities. We found that the resulting pTIF vastly outperforms cognitive and clinical evaluations on predicting individual variability in gene expression (GE) profiles. Furthermore, after regrouping the patients according to their predicted primary single-target interventions, we observed that these pTIF-based subgroups present distinctively altered molecular pathway signatures, supporting the across-population identification of dissimilar pathological stages, in active correspondence with different therapeutic needs. The results further evidence the imprecision of using broad clinical categories for understanding individual molecular alterations and selecting appropriate therapeutic needs. To our knowledge, this is the first study highlighting the direct link between multifactorial brain dynamics, predicted treatment responses, and molecular alterations at the patient level. Inspired by the principles of PM, the proposed pTIF framework is a promising step towards biomarker-driven assisted therapeutic interventions, with additional important implications for selective enrollment of patients in clinical trials.
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Affiliation(s)
- Yasser Iturria-Medina
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada; Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada.
| | | | - Alan C Evans
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, Canada; Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Canada
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35
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Sanchez-Rodriguez LM, Iturria-Medina Y, Baines EA, Mallo SC, Dousty M, Sotero RC. Design of optimal nonlinear network controllers for Alzheimer's disease. PLoS Comput Biol 2018; 14:e1006136. [PMID: 29795548 PMCID: PMC5967700 DOI: 10.1371/journal.pcbi.1006136] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 04/12/2018] [Indexed: 12/26/2022] Open
Abstract
Brain stimulation can modulate the activity of neural circuits impaired by Alzheimer’s disease (AD), having promising clinical benefit. However, all individuals with the same condition currently receive identical brain stimulation, with limited theoretical basis for this generic approach. In this study, we introduce a control theory framework for obtaining exogenous signals that revert pathological electroencephalographic activity in AD at a minimal energetic cost, while reflecting patients’ biological variability. We used anatomical networks obtained from diffusion magnetic resonance images acquired by the Alzheimer’s Disease Neuroimaging Initiative (ADNI) as mediators for the interaction between Duffing oscillators. The nonlinear nature of the brain dynamics is preserved, given that we extend the so-called state-dependent Riccati equation control to reflect the stimulation objective in the high-dimensional neural system. By considering nonlinearities in our model, we identified regions for which control inputs fail to correct abnormal activity. There are changes to the way stimulated regions are ranked in terms of the energetic cost of controlling the entire network, from a linear to a nonlinear approach. We also found that limbic system and basal ganglia structures constitute the top target locations for stimulation in AD. Patients with highly integrated anatomical networks–namely, networks having low average shortest path length, high global efficiency–are the most suitable candidates for the propagation of stimuli and consequent success on the control task. Other diseases associated with alterations in brain dynamics and the self-control mechanisms of the brain can be addressed through our framework. This work aims to close the knowledge gap between theory and experiment in brain stimulation. Previous modeling approaches for stimulation have overlooked the nonlinear dynamical nature of the brain and failed to shed light on efficient mechanisms for the exogenous control of the brain. Amid the current efforts for developing personalized medicine, we introduce a framework for producing tailored stimulation signals, based on individual neuroimaging data and innovative modeling. This is the first time, to our knowledge, that brain stimulation for the most common cause of dementia, Alzheimer’s disease, is theoretically addressed. Our approach leads to the identification of potential target regions and subjects to successfully respond to brain stimulation therapies and yields various disease-reverting signals. Although focused on Alzheimer’s in this study, our methodology could be applied to other clinical conditions characterized by abnormalities in brain dynamics, like epilepsy and Parkinson’s, the treatment of which can benefit from the use of optimal control strategies.
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Affiliation(s)
- Lazaro M. Sanchez-Rodriguez
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- * E-mail: (LMSR); (RCS)
| | - Yasser Iturria-Medina
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada
| | - Erica A. Baines
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Sabela C. Mallo
- Departament of Developmental Psychology, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Mehdy Dousty
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Roberto C. Sotero
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- * E-mail: (LMSR); (RCS)
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Carbonell F, Iturria-Medina Y, Evans AC. Mathematical Modeling of Protein Misfolding Mechanisms in Neurological Diseases: A Historical Overview. Front Neurol 2018; 9:37. [PMID: 29456521 PMCID: PMC5801313 DOI: 10.3389/fneur.2018.00037] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 01/16/2018] [Indexed: 12/12/2022] Open
Abstract
Protein misfolding refers to a process where proteins become structurally abnormal and lose their specific 3-dimensional spatial configuration. The histopathological presence of misfolded protein (MP) aggregates has been associated as the primary evidence of multiple neurological diseases, including Prion diseases, Alzheimer's disease, Parkinson's disease, and Creutzfeldt-Jacob disease. However, the exact mechanisms of MP aggregation and propagation, as well as their impact in the long-term patient's clinical condition are still not well understood. With this aim, a variety of mathematical models has been proposed for a better insight into the kinetic rate laws that govern the microscopic processes of protein aggregation. Complementary, another class of large-scale models rely on modern molecular imaging techniques for describing the phenomenological effects of MP propagation over the whole brain. Unfortunately, those neuroimaging-based studies do not take full advantage of the tremendous capabilities offered by the chemical kinetics modeling approach. Actually, it has been barely acknowledged that the vast majority of large-scale models have foundations on previous mathematical approaches that describe the chemical kinetics of protein replication and propagation. The purpose of the current manuscript is to present a historical review about the development of mathematical models for describing both microscopic processes that occur during the MP aggregation and large-scale events that characterize the progression of neurodegenerative MP-mediated diseases.
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Affiliation(s)
| | - Yasser Iturria-Medina
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, QC, Canada
| | - Alan C. Evans
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, QC, Canada
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, QC, Canada
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Tremblay S, Iturria-Medina Y, Mateos-Pérez JM, Evans AC, De Beaumont L. Defining a multimodal signature of remote sports concussions. Eur J Neurosci 2017; 46:1956-1967. [DOI: 10.1111/ejn.13583] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 03/28/2017] [Accepted: 03/30/2017] [Indexed: 12/11/2022]
Affiliation(s)
| | - Yasser Iturria-Medina
- Montreal Neurological Institute; McGill University; Montreal QC Canada
- Ludmer Center for Neuroinformatics and Mental Health; McGill University; Montreal QC Canada
| | - José María Mateos-Pérez
- Montreal Neurological Institute; McGill University; Montreal QC Canada
- Ludmer Center for Neuroinformatics and Mental Health; McGill University; Montreal QC Canada
| | - Alan C. Evans
- Montreal Neurological Institute; McGill University; Montreal QC Canada
- Ludmer Center for Neuroinformatics and Mental Health; McGill University; Montreal QC Canada
| | - Louis De Beaumont
- Centre de Recherche de l'Hôpital du Sacré-Coeur de Montréal; Montreal QC Canada
- Department of Surgery; Université de Montréal; Montreal QC H3C 3J7 Canada
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Román FJ, Iturria-Medina Y, Martínez K, Karama S, Burgaleta M, Evans AC, Jaeggi SM, Colom R. Enhanced structural connectivity within a brain sub-network supporting working memory and engagement processes after cognitive training. Neurobiol Learn Mem 2017; 141:33-43. [PMID: 28323202 DOI: 10.1016/j.nlm.2017.03.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 03/06/2017] [Accepted: 03/15/2017] [Indexed: 11/17/2022]
Abstract
The structural connectome provides relevant information about experience and training-related changes in the brain. Here, we used network-based statistics (NBS) and graph theoretical analyses to study structural changes in the brain as a function of cognitive training. Fifty-six young women were divided in two groups (experimental and control). We assessed their cognitive function before and after completing a working memory intervention using a comprehensive battery that included fluid and crystallized abilities, working memory and attention control, and we also obtained structural MRI images. We acquired and analyzed diffusion-weighted images to reconstruct the anatomical connectome and we computed standardized changes in connectivity as well as group differences across time using NBS. We also compared group differences relying on a variety of graph-theory indices (clustering, characteristic path length, global and local efficiency and strength) for the whole network as well as for the sub-network derived from NBS analyses. Finally, we calculated correlations between these graph indices and training performance as well as the behavioral changes in cognitive function. Our results revealed enhanced connectivity for the training group within one specific network comprised of nodes/regions supporting cognitive processes required by the training (working memory, interference resolution, inhibition, and task engagement). Significant group differences were also observed for strength and global efficiency indices in the sub-network detected by NBS. Therefore, the connectome approach is a valuable method for tracking the effects of cognitive training interventions across specific sub-networks. Moreover, this approach allowsfor the computation of graph theoretical network metricstoquantifythetopological architecture of the brain networkdetected. The observed structural brain changes support the behavioral results reported earlier (see Colom, Román, et al., 2013).
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Affiliation(s)
- Francisco J Román
- Universidad Autónoma de Madrid, Madrid, Spain; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, USA.
| | | | - Kenia Martínez
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del área de Salud Mental (CIBERSAM), Madrid, Spain
| | - Sherif Karama
- Montreal Neurological Institute (MNI), McGill University, Montreal, Canada
| | | | - Alan C Evans
- Montreal Neurological Institute (MNI), McGill University, Montreal, Canada
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Carbonell F, Zijdenbos AP, McLaren DG, Iturria-Medina Y, Bedell BJ. Modulation of glucose metabolism and metabolic connectivity by β-amyloid. J Cereb Blood Flow Metab 2016; 36:2058-2071. [PMID: 27301477 PMCID: PMC5363668 DOI: 10.1177/0271678x16654492] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 05/17/2016] [Indexed: 11/17/2022]
Abstract
Glucose hypometabolism in the pre-clinical stage of Alzheimer's disease (AD) has been primarily associated with the APOE ɛ4 genotype, rather than fibrillar β-amyloid. In contrast, aberrant patterns of metabolic connectivity are more strongly related to β-amyloid burden than APOE ɛ4 status. A major limitation of previous studies has been the dichotomous classification of subjects as amyloid-positive or amyloid-negative. Dichotomous treatment of a continuous variable, such as β-amyloid, potentially obscures the true relationship with metabolism and reduces the power to detect significant changes in connectivity. In the present work, we assessed alterations of glucose metabolism and metabolic connectivity as continuous function of β-amyloid burden using positron emission tomography scans from the Alzheimer's Disease Neuroimaging Initiative study. Modeling β-amyloid as a continuous variable resulted in better model fits and improved power compared to the dichotomous model. Using this continuous model, we found that both APOE ɛ4 genotype and β-amyloid burden are strongly associated with glucose hypometabolism at early stages of Alzheimer's disease. We also determined that the cumulative effects of β-amyloid deposition result in a particular pattern of altered metabolic connectivity, which is characterized by global, synchronized hypometabolism at early stages of the disease process, followed by regionally heterogeneous, progressive hypometabolism.
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Affiliation(s)
| | | | | | | | - Barry J Bedell
- Biospective Inc., Montreal, Canada.,McGill University, Montreal, Canada
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Evans AC, Karama S, Vasung L, Iturria-Medina Y. Understanding brain development: a major step. Lancet Neurol 2016; 16:178-179. [PMID: 27692495 DOI: 10.1016/s1474-4422(16)30232-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 09/02/2016] [Indexed: 11/19/2022]
Affiliation(s)
- Alan C Evans
- Montreal Neurological Institute, McGill University, Montreal, QC Canada.
| | - Sherif Karama
- Douglas Hospital Research Centre, McGill University, Montreal, QC Canada
| | - Lana Vasung
- Department of Pediatrics, Université de Genève, Geneva, Switzerland
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Iturria-Medina Y, Sotero RC, Toussaint PJ, Mateos-Pérez JM, Evans AC. Early role of vascular dysregulation on late-onset Alzheimer's disease based on multifactorial data-driven analysis. Nat Commun 2016; 7:11934. [PMID: 27327500 PMCID: PMC4919512 DOI: 10.1038/ncomms11934] [Citation(s) in RCA: 708] [Impact Index Per Article: 88.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 05/13/2016] [Indexed: 02/06/2023] Open
Abstract
Multifactorial mechanisms underlying late-onset Alzheimer's disease (LOAD) are poorly characterized from an integrative perspective. Here spatiotemporal alterations in brain amyloid-β deposition, metabolism, vascular, functional activity at rest, structural properties, cognitive integrity and peripheral proteins levels are characterized in relation to LOAD progression. We analyse over 7,700 brain images and tens of plasma and cerebrospinal fluid biomarkers from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Through a multifactorial data-driven analysis, we obtain dynamic LOAD-abnormality indices for all biomarkers, and a tentative temporal ordering of disease progression. Imaging results suggest that intra-brain vascular dysregulation is an early pathological event during disease development. Cognitive decline is noticeable from initial LOAD stages, suggesting early memory deficit associated with the primary disease factors. High abnormality levels are also observed for specific proteins associated with the vascular system's integrity. Although still subjected to the sensitivity of the algorithms and biomarkers employed, our results might contribute to the development of preventive therapeutic interventions.
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Affiliation(s)
- Y. Iturria-Medina
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada H3A 2B4
| | - R. C. Sotero
- Department of Radiology and Hotchkiss Brain institute, University of Calgary, Calgary, Alberta, Canada T2N 4N1
| | - P. J. Toussaint
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada H3A 2B4
| | - J. M. Mateos-Pérez
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada H3A 2B4
| | - A. C. Evans
- Department of Neurology & Neurosurgery, McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4
- Ludmer Centre for NeuroInformatics and Mental Health, Montreal, Quebec, Canada H3A 2B4
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Canales-Rodríguez EJ, Daducci A, Sotiropoulos SN, Caruyer E, Aja-Fernández S, Radua J, Yurramendi Mendizabal JM, Iturria-Medina Y, Melie-García L, Alemán-Gómez Y, Thiran JP, Sarró S, Pomarol-Clotet E, Salvador R. Spherical Deconvolution of Multichannel Diffusion MRI Data with Non-Gaussian Noise Models and Spatial Regularization. PLoS One 2015; 10:e0138910. [PMID: 26470024 PMCID: PMC4607500 DOI: 10.1371/journal.pone.0138910] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/06/2015] [Indexed: 11/28/2022] Open
Abstract
Spherical deconvolution (SD) methods are widely used to estimate the intra-voxel white-matter fiber orientations from diffusion MRI data. However, while some of these methods assume a zero-mean Gaussian distribution for the underlying noise, its real distribution is known to be non-Gaussian and to depend on many factors such as the number of coils and the methodology used to combine multichannel MRI signals. Indeed, the two prevailing methods for multichannel signal combination lead to noise patterns better described by Rician and noncentral Chi distributions. Here we develop a Robust and Unbiased Model-BAsed Spherical Deconvolution (RUMBA-SD) technique, intended to deal with realistic MRI noise, based on a Richardson-Lucy (RL) algorithm adapted to Rician and noncentral Chi likelihood models. To quantify the benefits of using proper noise models, RUMBA-SD was compared with dRL-SD, a well-established method based on the RL algorithm for Gaussian noise. Another aim of the study was to quantify the impact of including a total variation (TV) spatial regularization term in the estimation framework. To do this, we developed TV spatially-regularized versions of both RUMBA-SD and dRL-SD algorithms. The evaluation was performed by comparing various quality metrics on 132 three-dimensional synthetic phantoms involving different inter-fiber angles and volume fractions, which were contaminated with noise mimicking patterns generated by data processing in multichannel scanners. The results demonstrate that the inclusion of proper likelihood models leads to an increased ability to resolve fiber crossings with smaller inter-fiber angles and to better detect non-dominant fibers. The inclusion of TV regularization dramatically improved the resolution power of both techniques. The above findings were also verified in human brain data.
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Affiliation(s)
- Erick J. Canales-Rodríguez
- FIDMAG Germanes Hospitalàries, C/ Dr. Antoni Pujadas, 38, 08830, Sant Boi de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
- * E-mail:
| | - Alessandro Daducci
- Signal Processing Lab (LTS5), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- University Hospital Center (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Stamatios N. Sotiropoulos
- Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), University of Oxford, John Radcliffe Hospital, Oxford, OX39DU, United Kingdom
| | - Emmanuel Caruyer
- CNRS—IRISA (UMR 6074), Inria, VisAGeS Project-Team, INSERM, VisAGeS U746, Université de Rennes 1, Campus de Beaulieu, 35042, Rennes Cedex, France
| | - Santiago Aja-Fernández
- Laboratorio de Procesado de Imagen (LPI), ETSI Telecomunicación, Universidad de Valladolid, Valladolid, Spain
| | - Joaquim Radua
- FIDMAG Germanes Hospitalàries, C/ Dr. Antoni Pujadas, 38, 08830, Sant Boi de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jesús M. Yurramendi Mendizabal
- Departamento de Ciencia de la Computación e Inteligencial Artificial, Universidad del País Vasco, Euskal Herriko Unibertsitatea, Spain
| | - Yasser Iturria-Medina
- McConnell Brain Imaging Center, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Lester Melie-García
- The Neuroimaging Research Laboratory, Laboratoire de Recherche en Neuroimagerie: LREN, Department of Clinical Neurosciences, University Hospital Center (CHUV), Lausanne, Switzerland
| | - Yasser Alemán-Gómez
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
- Departamento de Bioingeniería e Ingeniería Aeroespacial. Universidad Carlos III de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
| | - Jean-Philippe Thiran
- Signal Processing Lab (LTS5), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- University Hospital Center (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland
| | - Salvador Sarró
- FIDMAG Germanes Hospitalàries, C/ Dr. Antoni Pujadas, 38, 08830, Sant Boi de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
| | - Edith Pomarol-Clotet
- FIDMAG Germanes Hospitalàries, C/ Dr. Antoni Pujadas, 38, 08830, Sant Boi de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
| | - Raymond Salvador
- FIDMAG Germanes Hospitalàries, C/ Dr. Antoni Pujadas, 38, 08830, Sant Boi de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, C/Dr Esquerdo, 46, 28007, Madrid, Spain
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Zeighami Y, Ulla M, Iturria-Medina Y, Dadar M, Zhang Y, Larcher KMH, Fonov V, Evans AC, Collins DL, Dagher A. Network structure of brain atrophy in de novo Parkinson's disease. eLife 2015; 4:e08440. [PMID: 26344547 PMCID: PMC4596689 DOI: 10.7554/elife.08440] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 09/05/2015] [Indexed: 01/01/2023] Open
Abstract
We mapped the distribution of atrophy in Parkinson's disease (PD) using magnetic resonance imaging (MRI) and clinical data from 232 PD patients and 117 controls from the Parkinson's Progression Markers Initiative. Deformation-based morphometry and independent component analysis identified PD-specific atrophy in the midbrain, basal ganglia, basal forebrain, medial temporal lobe, and discrete cortical regions. The degree of atrophy reflected clinical measures of disease severity. The spatial pattern of atrophy demonstrated overlap with intrinsic networks present in healthy brain, as derived from functional MRI. Moreover, the degree of atrophy in each brain region reflected its functional and anatomical proximity to a presumed disease epicenter in the substantia nigra, compatible with a trans-neuronal spread of the disease. These results support a network-spread mechanism in PD. Finally, the atrophy pattern in PD was also seen in healthy aging, where it also correlated with the loss of striatal dopaminergic innervation.
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Affiliation(s)
- Yashar Zeighami
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Miguel Ulla
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
- Service de Neurologie A, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Yasser Iturria-Medina
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Mahsa Dadar
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Yu Zhang
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | | | - Vladimir Fonov
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Alan C Evans
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - D Louis Collins
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Alain Dagher
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
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Iturria-Medina Y, Evans AC. On the central role of brain connectivity in neurodegenerative disease progression. Front Aging Neurosci 2015; 7:90. [PMID: 26052284 PMCID: PMC4439541 DOI: 10.3389/fnagi.2015.00090] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 05/01/2015] [Indexed: 12/12/2022] Open
Abstract
Increased brain connectivity, in all its variants, is often considered an evolutionary advantage by mediating complex sensorimotor function and higher cognitive faculties. Interaction among components at all spatial scales, including genes, proteins, neurons, local neuronal circuits and macroscopic brain regions, are indispensable for such vital functions. However, a growing body of evidence suggests that, from the microscopic to the macroscopic levels, such connections might also be a conduit for in intra-brain disease spreading. For instance, cell-to-cell misfolded proteins (MP) transmission and neuronal toxicity are prominent connectivity-mediated factors in aging and neurodegeneration. This article offers an overview of connectivity dysfunctions associated with neurodegeneration, with a specific focus on how these may be central to both normal aging and the neuropathologic degenerative progression.
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Affiliation(s)
- Yasser Iturria-Medina
- Montreal Neurological Institute Montreal, QC, Canada ; Ludmer Center for NeuroInformatics and Mental Health Montreal, QC, Canada
| | - Alan C Evans
- Montreal Neurological Institute Montreal, QC, Canada ; Ludmer Center for NeuroInformatics and Mental Health Montreal, QC, Canada
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Iturria-Medina Y, Sotero RC, Toussaint PJ, Evans AC. Epidemic spreading model to characterize misfolded proteins propagation in aging and associated neurodegenerative disorders. PLoS Comput Biol 2014; 10:e1003956. [PMID: 25412207 PMCID: PMC4238950 DOI: 10.1371/journal.pcbi.1003956] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 10/01/2014] [Indexed: 12/20/2022] Open
Abstract
Misfolded proteins (MP) are a key component in aging and associated neurodegenerative disorders. For example, misfolded Amyloid-ß (Aß) and tau proteins are two neuropathogenic hallmarks of Alzheimer's disease. Mechanisms underlying intra-brain MP propagation/deposition remain essentially uncharacterized. Here, is introduced an epidemic spreading model (ESM) for MP dynamics that considers propagation-like interactions between MP agents and the brain's clearance response across the structural connectome. The ESM reproduces advanced Aß deposition patterns in the human brain (explaining 46∼56% of the variance in regional Aß loads, in 733 subjects from the ADNI database). Furthermore, this model strongly supports a) the leading role of Aß clearance deficiency and early Aß onset age during Alzheimer's disease progression, b) that effective anatomical distance from Aß outbreak region explains regional Aß arrival time and Aß deposition likelihood, c) the multi-factorial impact of APOE e4 genotype, gender and educational level on lifetime intra-brain Aß propagation, and d) the modulatory impact of Aß propagation history on tau proteins concentrations, supporting the hypothesis of an interrelated pathway between Aß pathophysiology and tauopathy. To our knowledge, the ESM is the first computational model highlighting the direct link between structural brain networks, production/clearance of pathogenic proteins and associated intercellular transfer mechanisms, individual genetic/demographic properties and clinical states in health and disease. In sum, the proposed ESM constitutes a promising framework to clarify intra-brain region to region transference mechanisms associated with aging and neurodegenerative disorders. Misfolded proteins (MP) mechanisms are a characteristic pathogenic feature of most prevalent human neurodegenerative diseases, such as Alzheimer's disease (AD). Characterizing the mechanisms underlying intra-brain MP propagation and deposition still constitutes a major challenge. Here, we hypothesize that these complex mechanisms can be accurately described by epidemic spreading-like interactions between infectious-like agents (MP) and the brain's MP clearance response, which are constrained by the brain's connectional architecture. Consequently, we have developed a stochastic epidemic spreading model (ESM) of MP propagation/deposition that allows for reconstructing individual lifetime histories of intra-brain MP propagation, and the subsequent analysis of factors that promote propagation/deposition (e.g., MP production and clearance). Using 733 individual PET Amyloid-ß (Aß) datasets, we show that ESM explains advanced Aß deposition patterns in healthy and diseased (AD) brains. More importantly, it offers new avenues for our understanding of the mechanisms underlying MP mediated disorders. For instance, the results strongly support the growing body of evidence suggesting the leading role of a reduced Aβ clearance on AD progression and the modulatory impact of Aß mechanisms on tau proteins concentrations, which could imply a turning point for associated therapeutic mitigation strategies.
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Affiliation(s)
| | | | | | - Alan C. Evans
- Montreal Neurological Institute, Montreal, Quebec, Canada
- * E-mail: (YIM); (ACE)
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Li M, Chen H, Wang J, Liu F, Long Z, Wang Y, Iturria-Medina Y, Zhang J, Yu C, Chen H. Handedness- and hemisphere-related differences in small-world brain networks: a diffusion tensor imaging tractography study. Brain Connect 2014; 4:145-56. [PMID: 24564422 DOI: 10.1089/brain.2013.0211] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Previous behavioral and scanning studies have suggested that handedness is associated with differences in brain morphology as well as in anatomical and functional lateralization. However, little is known about the topological organization of the white matter (WM) structural networks related to handedness. We employed diffusion tensor imaging tractography to investigate handedness- and hemisphere-related differences in the topological organization of the human cortical anatomical network. After constructing left hemispheric/right hemispheric weighted structural networks in 32 right-handed and 24 left-handed healthy individuals, we analyzed the networks by graph theoretic analysis. We found that both the right and left hemispheric WM structural networks in the two groups possessed small-world attributes (high local clustering and short paths between nodes), findings which are consistent with recent results from whole-brain structural networks. In addition, the right hemisphere tended to be more efficient than the left hemisphere, suggesting a high efficiency of general information processing in the right hemisphere. Finally, we found that the right-handed subjects had significant asymmetries in small-world properties (normalized clustering coefficient γ, normalized path length λ, and small-worldness σ), while left-handed subjects had fewer asymmetries. Our findings from large-scale brain networks aid in understanding the structural substrates underlying handedness-related and hemisphere-related differences in cognition and behavior.
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Affiliation(s)
- Meiling Li
- 1 Key Laboratory for Neuroinformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China , Chengdu, China
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Dacosta-Aguayo R, Graña M, Iturria-Medina Y, Fernández-Andújar M, López-Cancio E, Cáceres C, Bargalló N, Barrios M, Clemente I, Toran P, Forés R, Dávalos A, Auer T, Mataró M. Impairment of functional integration of the default mode network correlates with cognitive outcome at three months after stroke. Hum Brain Mapp 2014; 36:577-90. [PMID: 25324040 PMCID: PMC4312977 DOI: 10.1002/hbm.22648] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Revised: 08/14/2014] [Accepted: 09/23/2014] [Indexed: 01/05/2023] Open
Abstract
Resting‐state studies conducted with stroke patients are scarce. The study of brain activity and connectivity at rest provides a unique opportunity for the investigation of brain rewiring after stroke and plasticity changes. This study sought to identify dynamic changes in the functional organization of the default mode network (DMN) of stroke patients at three months after stroke. Eleven patients (eight male and three female; age range: 48–72) with right cortical and subcortical ischemic infarctions and 17 controls (eleven males and six females; age range: 57–69) were assessed by neurological and neuropsychological examinations and scanned with resting‐state functional magnetic ressonance imaging. First, we explored group differences in functional activity within the DMN by means of probabilistic independent component analysis followed by a dual regression approach. Second, we estimated functional connectivity between 11 DMN nodes both locally by means of seed‐based connectivity analysis, as well as globally by means of graph‐computation analysis. We found that patients had greater DMN activity in the left precuneus and the left anterior cingulate gyrus when compared with healthy controls (P < 0.05 family‐wise error corrected). Seed‐based connectivity analysis showed that stroke patients had significant impairment (P = 0.014; threshold = 2.00) in the connectivity between the following five DMN nodes: left superior frontal gyrus (lSFG) and posterior cingulate cortex (t = 2.01); left parahippocampal gyrus and right superior frontal gyrus (t = 2.11); left parahippocampal gyrus and lSFG (t = 2.39); right parietal and lSFG (t = 2.29). Finally, mean path length obtained from graph‐computation analysis showed positive correlations with semantic fluency test (rs = 0.454; P = 0.023), phonetic fluency test (rs = 0.523; P = 0.007) and the mini mental state examination (rs = 0.528; P = 0.007). In conclusion, the ability to regulate activity of the DMN appears to be a central part of normal brain function in stroke patients. Our study expands the understanding of the changes occurring in the brain after stroke providing a new avenue for investigating lesion‐induced network plasticity. Hum Brain Mapp 36:577–590, 2015. © 2014 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Rosalia Dacosta-Aguayo
- Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain; Group of Computational Intelligence, Department of CCIA, University of the Basque Country UPV/EHU, San Sebastian, Spain
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Pérez A, García-Pentón L, Canales-Rodríguez EJ, Lerma-Usabiaga G, Iturria-Medina Y, Román FJ, Davidson D, Alemán-Gómez Y, Acha J, Carreiras M. Brain morphometry of Dravet syndrome. Epilepsy Res 2014; 108:1326-34. [PMID: 25048308 DOI: 10.1016/j.eplepsyres.2014.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 06/06/2014] [Accepted: 06/28/2014] [Indexed: 01/12/2023]
Abstract
The aim of this study was to identify differential global and local brain structural patterns in Dravet Syndrome (DS) patients as compared with a control subject group, using brain morphometry techniques which provide a quantitative whole-brain structural analysis that allows for specific patterns to be generalized across series of individuals. Nine patients with the diagnosis of DS that tested positive for mutation in the SCN1A gene and nine well-matched healthy controls were investigated using voxel brain morphometry (VBM), cortical thickness and cortical gyrification measurements. Global volume reductions of gray matter (GM) and white matter (WM) were related to DS. Local volume reductions corresponding to several white matter regions in brainstem, cerebellum, corpus callosum, corticospinal tracts and association fibers (left inferior fronto-occipital fasciculus and left uncinate fasciculus) were also found. Furthermore, DS showed a reduced cortical folding in the right precentral gyrus. The present findings describe DS-related brain structure abnormalities probably linked to the expression of the SCN1A mutation.
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Affiliation(s)
- Alejandro Pérez
- Basque Center on Cognition Brain and Language, BCBL, Donostia-San Sebastián, Spain.
| | - Lorna García-Pentón
- Basque Center on Cognition Brain and Language, BCBL, Donostia-San Sebastián, Spain
| | - Erick J Canales-Rodríguez
- Centro de Investigación Biomédica en Red de Salud Mental (CIBERSam), 28007 Madrid, Spain; FIDMAG Germanes Hospitalàries, 08830, Sant Boi de Llobregat, Barcelona, Spain
| | | | | | - Francisco J Román
- Facultad de Psicología, Departamento de Psicología Biológica y de la Salud, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Doug Davidson
- Basque Center on Cognition Brain and Language, BCBL, Donostia-San Sebastián, Spain
| | - Yasser Alemán-Gómez
- Instituto de Investigación Sanitaria Gregorio Marañón, IiSGM, HGUGM, CIBERSAM, Madrid, Spain
| | - Joana Acha
- Euskal Herriko Unibertsitatea/Universidad del País Vasco EHU/UPV, Bilbao, Spain
| | - Manuel Carreiras
- Basque Center on Cognition Brain and Language, BCBL, Donostia-San Sebastián, Spain; Euskal Herriko Unibertsitatea/Universidad del País Vasco EHU/UPV, Bilbao, Spain; Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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García-Pentón L, Pérez Fernández A, Iturria-Medina Y, Gillon-Dowens M, Carreiras M. Anatomical connectivity changes in the bilingual brain. Neuroimage 2013; 84:495-504. [PMID: 24018306 DOI: 10.1016/j.neuroimage.2013.08.064] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/01/2013] [Accepted: 08/29/2013] [Indexed: 11/28/2022] Open
Abstract
How the brain deals with more than one language and whether we need different or extra brain language sub-networks to support more than one language remain unanswered questions. Here, we investigate structural brain network differences between early bilinguals and monolinguals. Using diffusion-weighted MRI (DW-MRI) tractography techniques and a network-based statistic (NBS) procedure, we found two structural sub-networks more connected by white matter (WM) tracts in bilinguals than in monolinguals; confirming WM brain plasticity in bilinguals. One of these sub-networks comprises left frontal and parietal/temporal regions, while the other comprises left occipital and parietal/temporal regions and also the right superior frontal gyrus. Most of these regions have been related to language processing and monitoring; suggesting that bilinguals develop specialized language sub-networks to deal with the two languages. Additionally, a complex network analysis showed that these sub-networks are more graph-efficient in bilinguals than monolinguals and this increase seems to be at the expense of a whole-network graph-efficiency decrease.
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Affiliation(s)
- Lorna García-Pentón
- Basque Center on Cognition, Brain and Language (BCBL), Mikeletegui 69, 2, 20009 Donostia-San Sebastian, Gipuzkoa, Spain.
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Abstract
Graph-based brain anatomical network analysis models the brain as a graph whose nodes represent structural/functional regions, whereas the links between them represent nervous fiber connections. Initial studies of brain anatomical networks using this approach were devoted to describe the key organizational principles of the normal brain, while current trends seem to be more focused on detecting network alterations associated to specific brain disorders. Anatomical networks reconstructed using diffusion-weighed magnetic resonance-imaging techniques can be particularly useful in predicting abnormal brain states in which the white matter structure and, subsequently, the interconnections between gray matter regions are altered (e.g., due to the presence of diseases such as schizophrenia, stroke, multiple sclerosis, and dementia). This article offers an overview from early gross connectional anatomy explorations until more recent advances on anatomical brain network reconstruction approaches, with a specific focus on how the latter move toward the prediction of abnormal brain states. While anatomical graph-based predictor approaches are still at an early stage, they bear promising implications for individualized clinical diagnosis of neurological and psychiatric disorders, as well as for neurodevelopmental evaluations and subsequent assisted creation of educational strategies related to specific cognitive disorders.
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