1
|
Pressl C, Mätlik K, Kus L, Darnell P, Luo JD, Paul MR, Weiss AR, Liguore W, Carroll TS, Davis DA, McBride J, Heintz N. Selective vulnerability of layer 5a corticostriatal neurons in Huntington's disease. Neuron 2024; 112:924-941.e10. [PMID: 38237588 DOI: 10.1016/j.neuron.2023.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 08/18/2023] [Accepted: 12/13/2023] [Indexed: 01/30/2024]
Abstract
The properties of the cell types that are selectively vulnerable in Huntington's disease (HD) cortex, the nature of somatic CAG expansions of mHTT in these cells, and their importance in CNS circuitry have not been delineated. Here, we employed serial fluorescence-activated nuclear sorting (sFANS), deep molecular profiling, and single-nucleus RNA sequencing (snRNA-seq) of motor-cortex samples from thirteen predominantly early stage, clinically diagnosed HD donors and selected samples from cingulate, visual, insular, and prefrontal cortices to demonstrate loss of layer 5a pyramidal neurons in HD. Extensive mHTT CAG expansions occur in vulnerable layer 5a pyramidal cells, and in Betz cells, layers 6a and 6b neurons that are resilient in HD. Retrograde tracing experiments in macaque brains identify layer 5a neurons as corticostriatal pyramidal cells. We propose that enhanced somatic mHTT CAG expansion and altered synaptic function act together to cause corticostriatal disconnection and selective neuronal vulnerability in HD cerebral cortex.
Collapse
Affiliation(s)
- Christina Pressl
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Kert Mätlik
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Laura Kus
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Paul Darnell
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA
| | - Ji-Dung Luo
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - Matthew R Paul
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - Alison R Weiss
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - William Liguore
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - Thomas S Carroll
- Bioinformatics Resource Center, The Rockefeller University, New York, NY, USA
| | - David A Davis
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jodi McBride
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, USA
| | - Nathaniel Heintz
- Laboratory of Molecular Biology, The Rockefeller University, New York, NY, USA.
| |
Collapse
|
2
|
Pérot JB, Brouillet E, Flament J. The contribution of preclinical magnetic resonance imaging and spectroscopy to Huntington's disease. Front Aging Neurosci 2024; 16:1306312. [PMID: 38414634 PMCID: PMC10896846 DOI: 10.3389/fnagi.2024.1306312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 01/24/2024] [Indexed: 02/29/2024] Open
Abstract
Huntington's disease is an inherited disorder characterized by psychiatric, cognitive, and motor symptoms due to degeneration of medium spiny neurons in the striatum. A prodromal phase precedes the onset, lasting decades. Current biomarkers include clinical score and striatal atrophy using Magnetic Resonance Imaging (MRI). These markers lack sensitivity for subtle cellular changes during the prodromal phase. MRI and MR spectroscopy offer different contrasts for assessing metabolic, microstructural, functional, or vascular alterations in the disease. They have been used in patients and mouse models. Mouse models can be of great interest to study a specific mechanism of the degenerative process, allow better understanding of the pathogenesis from the prodromal to the symptomatic phase, and to evaluate therapeutic efficacy. Mouse models can be divided into three different constructions: transgenic mice expressing exon-1 of human huntingtin (HTT), mice with an artificial chromosome expressing full-length human HTT, and knock-in mouse models with CAG expansion inserted in the murine htt gene. Several studies have used MRI/S to characterized these models. However, the multiplicity of modalities and mouse models available complicates the understanding of this rich corpus. The present review aims at giving an overview of results obtained using MRI/S for each mouse model of HD, to provide a useful resource for the conception of neuroimaging studies using mouse models of HD. Finally, despite difficulties in translating preclinical protocols to clinical applications, many biomarkers identified in preclinical models have already been evaluated in patients. This review also aims to cover this aspect to demonstrate the importance of MRI/S for studying HD.
Collapse
Affiliation(s)
- Jean-Baptiste Pérot
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
- Institut du Cerveau – Paris Brain Institute – ICM, Sorbonne Université, Paris, France
| | - Emmanuel Brouillet
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
| | - Julien Flament
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center, Commissariat à l’Energie Atomique et aux Energies Alternatives, Centre National de la Recherche Scientifique, Université Paris-Saclay, Fontenay-aux-Roses, France
| |
Collapse
|
3
|
Hu B, Younes L, Bu X, Liu CF, Ratnanather JT, Paulsen J, Georgiou-Karistianis N, Miller MI, Ross C, Faria AV. Mixed longitudinal and cross-sectional analyses of deep gray matter and white matter using diffusion weighted images in premanifest and manifest Huntington's disease. Neuroimage Clin 2023; 39:103493. [PMID: 37582307 PMCID: PMC10448214 DOI: 10.1016/j.nicl.2023.103493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/29/2023] [Accepted: 08/07/2023] [Indexed: 08/17/2023]
Abstract
Changes in the brain of patients with Huntington's disease (HD) begin years before clinical onset, so it remains critical to identify biomarkers to track these early changes. Metrics derived from tensor modeling of diffusion-weighted MRIs (DTI), that indicate the microscopic brain structure, can add important information to regional volumetric measurements. This study uses two large-scale longitudinal, multicenter datasets, PREDICT-HD and IMAGE-HD, to trace changes in DTI of HD participants with a broad range of CAP scores (a product of CAG repeat expansion and age), including those with pre-manifest disease (i.e., prior to clinical onset). Utilizing a fully automated data-driven approach to study the whole brain divided in regions of interest, we traced changes in DTI metrics (diffusivity and fractional anisotropy) versus CAP scores, using sigmoidal and linear regression models. We identified points of inflection in the sigmoidal regression using change-point analysis. The deep gray matter showed more evident and earlier changes in DTI metrics over CAP scores, compared to the deep white matter. In the deep white matter, these changes were more evident and occurred earlier in superior and posterior areas, compared to anterior and inferior areas. The curves of mean diffusivity vs. age of HD participants within a fixed CAP score were different from those of controls, indicating that the disease has an additional effect to age on the microscopic brain structure. These results show the regional and temporal vulnerability of the white matter and deep gray matter in HD, with potential implications for experimental therapeutics.
Collapse
Affiliation(s)
- Beini Hu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Laurent Younes
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, USA
| | - Xuan Bu
- Department of Radiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Chin-Fu Liu
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - J Tilak Ratnanather
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Jane Paulsen
- Department of Psychiatry, Neurology, Psychological Brain Sciences, University of Iowa, USA; Department Neurology, University of Wisconsin-Madison, USA
| | - Nellie Georgiou-Karistianis
- School of Psychological Sciences and Turner Institute of Brain and Mental Health, Monash University, Australia
| | - Michael I Miller
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Christopher Ross
- Department of Psychiatry, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Andreia V Faria
- Department of Radiology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
| |
Collapse
|
4
|
Pérot JB, Célestine M, Palombo M, Dhenain M, Humbert S, Brouillet E, Flament J. Longitudinal multimodal MRI characterization of a knock-in mouse model of Huntington's disease reveals early gray and white matter alterations. Hum Mol Genet 2022; 31:3581-3596. [PMID: 35147158 PMCID: PMC9616570 DOI: 10.1093/hmg/ddac036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 01/19/2022] [Accepted: 01/31/2022] [Indexed: 11/24/2022] Open
Abstract
Pathogenesis of the inherited neurodegenerative disorder Huntington's disease (HD) is progressive with a long presymptomatic phase in which subtle changes occur up to 15 years before the onset of symptoms. Thus, there is a need for early, functional biomarker to better understand disease progression and to evaluate treatment efficacy far from onset. Recent studies have shown that white matter may be affected early in mutant HTT gene carriers. A previous study performed on 12 months old Ki140CAG mice showed reduced glutamate level measured by Chemical Exchange Saturation Transfer of glutamate (gluCEST), especially in the corpus callosum. In this study, we scanned longitudinally Ki140CAG mice with structural MRI, diffusion tensor imaging, gluCEST and magnetization transfer imaging, in order to assess white matter integrity over the life of this mouse model characterized by slow progression of symptoms. Our results show early defects of diffusion properties in the anterior part of the corpus callosum at 5 months of age, preceding gluCEST defects in the same region at 8 and 12 months that spread to adjacent regions. At 12 months, frontal and piriform cortices showed reduced gluCEST, as well as the pallidum. MT imaging showed reduced signal in the septum at 12 months. Cortical and striatal atrophy then appear at 18 months. Vulnerability of the striatum and motor cortex, combined with alterations of anterior corpus callosum, seems to point out the potential role of white matter in the brain dysfunction that characterizes HD and the pertinence of gluCEST and DTI as biomarkers in HD.
Collapse
Affiliation(s)
- Jean-Baptiste Pérot
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Fontenay -aux-Roses 92260, France
| | - Marina Célestine
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Fontenay -aux-Roses 92260, France
| | - Marco Palombo
- Department of Computer Science, Centre for Medical Image Computing, University College London, London WC1E 6BT, UK
| | - Marc Dhenain
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Fontenay -aux-Roses 92260, France
| | - Sandrine Humbert
- Université Grenoble Alpes, INSERM, U1216, Grenoble Institut Neurosciences, Grenoble 38000 , France
| | - Emmanuel Brouillet
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Fontenay -aux-Roses 92260, France
| | - Julien Flament
- Laboratoire des Maladies Neurodégénératives, Molecular Imaging Research Center (MIRCen), Université Paris-Saclay, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), Centre National de la Recherche Scientifique (CNRS), Fontenay -aux-Roses 92260, France
| |
Collapse
|
5
|
Oh SL, Chen CM, Wu YR, Valdes Hernandez M, Tsai CC, Cheng JS, Chen YL, Wu YM, Lin YC, Wang JJ. Fixel-Based Analysis Effectively Identifies White Matter Tract Degeneration in Huntington's Disease. Front Neurosci 2021; 15:711651. [PMID: 34588947 PMCID: PMC8473742 DOI: 10.3389/fnins.2021.711651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
Microstructure damage in white matter might be linked to regional and global atrophy in Huntington's Disease (HD). We hypothesize that degeneration of subcortical regions, including the basal ganglia, is associated with damage of white matter tracts linking these affected regions. We aim to use fixel-based analysis to identify microstructural changes in the white matter tracts. To further assess the associated gray matter damage, diffusion tensor-derived indices were measured from regions of interest located in the basal ganglia. Diffusion weighted images were acquired from 12 patients with HD and 12 healthy unrelated controls using a 3 Tesla scanner. Reductions in fixel-derived metrics occurs in major white matter tracts, noticeably in corpus callosum, internal capsule, and the corticospinal tract, which were closely co-localized with the regions of increased diffusivity in basal ganglia. These changes in diffusion can be attributed to potential axonal degeneration. Fixel-based analysis is effective in studying white matter tractography and fiber changes in HD.
Collapse
Affiliation(s)
- Sher Li Oh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Chiung-Mei Chen
- Department of Neurology, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yih-Ru Wu
- Department of Neurology, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Maria Valdes Hernandez
- Row Fogo Centre for Research into Ageing and the Brain, Department of Neuroimaging Sciences, The University of Edinburgh, Edinburgh, United Kingdom.,Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, United Kingdom
| | - Chih-Chien Tsai
- Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan
| | - Jur-Shan Cheng
- Clinical Informatics and Medical Statistics Research Center, College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Emergency Medicine, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yao-Liang Chen
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Yi-Ming Wu
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Chun Lin
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Jiun-Jie Wang
- Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan.,Department of Diagnostic Radiology, Chang Gung Memorial Hospital, Keelung, Taiwan.,Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan.,Medical Imaging Research Center, Institute for Radiological Research, Linkou Chang Gung Memorial Hospital, Chang Gung University, Taoyuan, Taiwan
| |
Collapse
|
6
|
Casella C, Kleban E, Rosser AE, Coulthard E, Rickards H, Fasano F, Metzler-Baddeley C, Jones DK. Multi-compartment analysis of the complex gradient-echo signal quantifies myelin breakdown in premanifest Huntington's disease. Neuroimage Clin 2021; 30:102658. [PMID: 33865029 PMCID: PMC8079666 DOI: 10.1016/j.nicl.2021.102658] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 12/04/2022]
Abstract
White matter (WM) alterations have been identified as a relevant pathological feature of Huntington's disease (HD). Increasing evidence suggests that WM changes in this disorder are due to alterations in myelin-associated biological processes. Multi-compartmental analysis of the complex gradient-echo MRI signal evolution in WM has been shown to quantify myelin in vivo, therefore pointing to the potential of this technique for the study of WM myelin changes in health and disease. This study first characterized the reproducibility of metrics derived from the complex multi-echo gradient-recalled echo (mGRE) signal across the corpus callosum in healthy participants, finding highest reproducibility in the posterior callosal segment. Subsequently, the same analysis pipeline was applied in this callosal region in a sample of premanifest HD patients (n = 19) and age, sex and education matched healthy controls (n = 21). In particular, we focused on two myelin-associated derivatives: i. the myelin water signal fraction (fm), a parameter dependent on myelin content; and ii. The difference in frequency between myelin and intra-axonal water pools (Δω), a parameter dependent on the ratio between the inner and the outer axonal radii. fm was found to be lower in HD patients (β = -0.13, p = 0.03), while Δω did not show a group effect. Performance in tests of working memory, executive function, social cognition and movement was also assessed, and a greater age-related decline in executive function was detected in HD patients (β = -0.06, p = 0.006), replicating previous evidence of executive dysfunction in HD. Finally, the correlation between fm, executive function, and proximity to disease onset was explored in patients, and a positive correlation between executive function and fm was detected (r = 0.542; p = 0.02). This study emphasises the potential of complex mGRE signal analysis for aiding understanding of HD pathogenesis and progression. Moreover, expanding on evidence from pathology and animal studies, it provides novel in vivo evidence supporting myelin breakdown as an early feature of HD.
Collapse
Affiliation(s)
- Chiara Casella
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF 24 4HQ, UK.
| | - Elena Kleban
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF 24 4HQ, UK
| | - Anne E Rosser
- Department of Neurology and Psychological Medicine, Hayden Ellis Building, Maindy Road, Cardiff CF24 4HQ, UK; School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK
| | | | - Hugh Rickards
- Birmingham and Solihull Mental Health NHS Foundation Trust, 50 Summer Hill Road, Birmingham B1 3RB, UK; Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Fabrizio Fasano
- Siemens Healthcare Ltd, Camberly, UK; Siemens Healthcare GmbH, Erlangen, Germany
| | - Claudia Metzler-Baddeley
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF 24 4HQ, UK
| | - Derek K Jones
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Maindy Road, Cardiff, CF 24 4HQ, UK
| |
Collapse
|
7
|
Zeun P, Scahill RI, Tabrizi SJ, Wild EJ. Fluid and imaging biomarkers for Huntington's disease. Mol Cell Neurosci 2019; 97:67-80. [PMID: 30807825 DOI: 10.1016/j.mcn.2019.02.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/25/2019] [Accepted: 02/12/2019] [Indexed: 01/18/2023] Open
Abstract
Huntington's disease is a chronic progressive neurodegenerative condition for which there is no disease-modifying treatment. The known genetic cause of Huntington's disease makes it possible to identify individuals destined to develop the disease and instigate treatments before the onset of symptoms. Multiple trials are already underway that target the cause of HD, yet clinical measures are often insensitive to change over typical clinical trial duration. Robust biomarkers of drug target engagement, disease severity and progression are required to evaluate the efficacy of treatments and concerted efforts are underway to achieve this. Biofluid biomarkers have potential advantages of direct quantification of biological processes at the molecular level, whilst imaging biomarkers can quantify related changes at a structural level in the brain. The most robust biofluid and imaging biomarkers can offer complementary information, providing a more comprehensive evaluation of disease stage and progression to inform clinical trial design and endpoints.
Collapse
Affiliation(s)
- Paul Zeun
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Rachael I Scahill
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Sarah J Tabrizi
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| | - Edward J Wild
- Huntington's Disease Centre, University College London (UCL) Institute of Neurology, London WC1N 3BG, United Kingdom.
| |
Collapse
|
8
|
Gatto RG, Ye AQ, Colon-Perez L, Mareci TH, Lysakowski A, Price SD, Brady ST, Karaman M, Morfini G, Magin RL. Detection of axonal degeneration in a mouse model of Huntington's disease: comparison between diffusion tensor imaging and anomalous diffusion metrics. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 32:461-471. [PMID: 30771034 DOI: 10.1007/s10334-019-00742-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/31/2018] [Accepted: 01/29/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The goal of this work is to study the changes in white matter integrity in R6/2, a well-established animal model of Huntington's disease (HD) that are captured by ex vivo diffusion imaging (DTI) using a high field MRI (17.6 T). MATERIALS AND METHODS DTI and continuous time random walk (CTRW) models were used to fit changes in the diffusion-weighted signal intensity in the corpus callosum of controls and in R6/2 mice. RESULTS A significant 13% decrease in fractional anisotropy, a 7% increase in axial diffusion, and a 33% increase in radial diffusion were observed between R6/2 and control mice. No change was observed in the CTRW beta parameter, but a significant decrease in the alpha parameter (- 21%) was measured. Histological analysis of the corpus callosum showed a decrease in axonal organization, myelin alterations, and astrogliosis. Electron microscopy studies demonstrated ultrastructural changes in degenerating axons, such as an increase in tortuosity in the R6/2 mice. CONCLUSIONS DTI and CTRW diffusion models display quantitative changes associated with the microstructural alterations observed in the corpus callosum of the R6/2 mice. The observed increase in the diffusivity and decrease in the alpha CTRW parameter providing support for the use of these diffusion models for non-invasive detection of white matter alterations in HD.
Collapse
Affiliation(s)
- Rodolfo G Gatto
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA.,Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA
| | - Allen Q Ye
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA
| | - Luis Colon-Perez
- Department of Neurology and Behavior, University of California at Irvine, Irvine, CA, USA.,Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Thomas H Mareci
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| | - Anna Lysakowski
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Steven D Price
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Muge Karaman
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, IL, USA
| | - Gerardo Morfini
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA
| | - Richard L Magin
- Department of Bioengineering, University of Illinois at Chicago, 851 S Morgan St, 218 SEO (MC 063), Chicago, IL, 60607, USA.
| |
Collapse
|
9
|
Ciarochi JA, Johnson HJ, Calhoun VD, Liu J, Espinoza FA, Bockholt HJ, Misiura M, Caprihan A, Plis S, Paulsen JS, Turner JA. Concurrent Cross-Sectional and Longitudinal Analyses of Multivariate White Matter Profiles and Clinical Functioning in Pre-Diagnosis Huntington Disease. J Huntingtons Dis 2019; 8:199-219. [PMID: 30932891 DOI: 10.3233/jhd-180332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Gray matter (GM) atrophy in the striatum and across the brain is a consistently reported feature of the Huntington Disease (HD) prodrome. More recently, widespread prodromal white matter (WM) degradation has also been detected. However, longitudinal WM studies are limited and conflicting, and most analyses comparing WM and clinical functioning have also been cross-sectional. OBJECTIVE We simultaneously assessed changes in WM and cognitive and motor functioning at various prodromal HD stages. METHODS Data from 1,336 (1,047 prodromal, 289 control) PREDICT-HD participants were analyzed (3,700 sessions). MRI images were used to create GM, WM, and cerebrospinal fluid probability maps. Using source-based morphometry, independent component analysis was applied to WM probability maps to extract covarying spatial patterns and their subject profiles. WM profiles were analyzed in two sets of linear mixed model (LMM) analyses: one to compare WM profiles across groups cross-sectionally and longitudinally, and one to concurrently compare WM profiles and clinical variables cross-sectionally and longitudinally within each group. RESULTS Findings illustrate widespread prodromal changes in GM-adjacent-WM, with premotor, supplementary motor, middle frontal and striatal changes early in the prodrome that subsequently extend sub-gyrally with progression. Motor functioning agreed most with WM until the near-onset prodromal stage, when Stroop interference was the best WM indicator. Across groups, Trail-Making Test part A outperformed other cognitive variables in its similarity to WM, particularly cross-sectionally. CONCLUSIONS Results suggest that distinct regions coincide with cognitive compared to motor functioning. Furthermore, at different prodromal stages, distinct regions appear to align best with clinical functioning. Thus, the informativeness of clinical measures may vary according to the type of data available (cross-sectional or longitudinal) as well as age and CAG-number.
Collapse
Affiliation(s)
| | - Hans J Johnson
- Department of Electrical and Computer Engineering, 1402 Seamans Center for the Engineering Arts and Science, The University of Iowa, Iowa City, IA, USA
| | - Vince D Calhoun
- The Mind Research Network, Albuquerque, NM, USA
- Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM, USA
| | - Jingyu Liu
- The Mind Research Network, Albuquerque, NM, USA
| | | | | | - Maria Misiura
- Department of Psychology, Georgia State University, Atlanta, GA, USA
| | | | - Sergey Plis
- The Mind Research Network, Albuquerque, NM, USA
| | - Jane S Paulsen
- Department of Psychiatry, Iowa Mental Health Clinical Research Center, University of Iowa, IA, USA
- Departments of Neurology and Psychology, University of Iowa, IA, USA
| | - Jessica A Turner
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
- Department of Psychology, Georgia State University, Atlanta, GA, USA
| |
Collapse
|
10
|
Fazio P, Paucar M, Svenningsson P, Varrone A. Novel Imaging Biomarkers for Huntington's Disease and Other Hereditary Choreas. Curr Neurol Neurosci Rep 2018; 18:85. [PMID: 30291526 PMCID: PMC6182636 DOI: 10.1007/s11910-018-0890-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF THE REVIEW Imaging biomarkers for neurodegenerative disorders are primarily developed with the goal to aid diagnosis, to monitor disease progression, and to assess the efficacy of disease-modifying therapies in support to clinical outcomes that may either show limited sensitivity or need extended time for their evaluation. This article will review the most recent concepts and findings in the field of neuroimaging applied to Huntington's disease and Huntington-like syndromes. Emphasis will be given to the discussion of potential pharmacodynamic biomarkers for clinical trials in Huntington's disease (HD) and of neuroimaging tools that can be used as diagnostic biomarkers in HD-like syndromes. RECENT FINDINGS Several magnetic resonance (MR) and positron emission tomography (PET) molecular imaging tools have been identified as potential pharmacodynamic biomarkers and others are in the pipeline after preclinical validation. MRI and 18F-fluorodeoxyglucose PET can be considered useful supportive diagnostic tools for the differentiation of other HD-like syndromes. New trials in HD have the primary goal to lower mutant huntingtin (mHTT) protein levels in the brain in order to reduce or alter the progression of the disease. MR and PET molecular imaging markers have been developed as tools to monitor disease progression and to evaluate treatment outcomes of disease-modifying trials in HD. These markers could be used alone or in combination for detecting structural and pharmacodynamic changes potentially associated with the lowering of mHTT.
Collapse
Affiliation(s)
- Patrik Fazio
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, R5:02 Karolinska University Hospital, SE-171 76, Stockholm, Sweden.
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden.
| | - Martin Paucar
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Per Svenningsson
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
- Department of Clinical Neuroscience, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm County Council, R5:02 Karolinska University Hospital, SE-171 76, Stockholm, Sweden
| |
Collapse
|
11
|
Zhang J, Gregory S, Scahill RI, Durr A, Thomas DL, Lehericy S, Rees G, Tabrizi SJ, Zhang H. In vivo characterization of white matter pathology in premanifest huntington's disease. Ann Neurol 2018; 84:497-504. [PMID: 30063250 PMCID: PMC6221120 DOI: 10.1002/ana.25309] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 07/24/2018] [Accepted: 07/28/2018] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Huntington's disease (HD) is a monogenic, fully penetrant neurodegenerative disorder, providing an ideal model for understanding brain changes occurring in the years prior to disease onset. Diffusion tensor imaging (DTI) studies show widespread white matter disorganization in the early premanifest stages (pre-HD). However, although DTI has proved informative, it provides only limited information about underlying changes in tissue properties. Neurite orientation dispersion and density imaging (NODDI) is a novel magnetic resonance imaging (MRI) technique for characterizing axonal pathology more specifically, providing metrics that separately quantify axonal density and axonal organization. Here, we provide the first in vivo characterization of white matter pathology in pre-HD using NODDI. METHODS Diffusion-weighted MRI data that support DTI and NODDI were acquired from 38 pre-HD and 45 control participants. Using whole-brain and region-of-interest analyses, NODDI metrics were compared between groups and correlated with clinical scores of disease progression. Whole-brain changes in DTI metrics were also examined. RESULTS The pre-HD group displayed widespread reductions in axonal density compared with control participants; this correlated with measures of clinical disease progression in the body and genu of the corpus callosum. There was also evidence in the pre-HD group of increased coherence of axonal packing in the white matter surrounding the basal ganglia. INTERPRETATION Our findings suggest that reduced axonal density is one of the major factors underlying white matter pathology in pre-HD, coupled with altered local organization in areas surrounding the basal ganglia. NODDI metrics show promise in providing more specific information about the biological processes underlying HD and neurodegeneration per se. Ann Neurol 2018;84:497-504.
Collapse
Affiliation(s)
- Jiaying Zhang
- Department of Computer Science and Centre for Medical Image ComputingUniversity College LondonLondonUnited Kingdom
| | - Sarah Gregory
- Huntington's Disease Research Centre, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
- Wellcome Trust Centre for Neuroimaging, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Rachael I. Scahill
- Huntington's Disease Research Centre, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
- Department of Neurodegenerative Disease, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Alexandra Durr
- ICM – Institut du Cerveau et de la Moelle Epinière, INSERM U1127, CNRS UMR7225, Sorbonne Universités – UPMC Université Paris VI UMR_S1127 and APHP, Genetic departmentPitié–Salpêtrière University HospitalParisFrance
| | - David L. Thomas
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
- Leonard Wolfson Experimental Neurology Centre, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Stéphane Lehericy
- Neuroimaging Research Center, Brain and Spinal Cord InstitutePierre and Marie Curie University, Inserm UMR1127, CNRS 7225ParisFrance
| | - Geraint Rees
- Wellcome Trust Centre for Neuroimaging, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Sarah J. Tabrizi
- Huntington's Disease Research Centre, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
- Wellcome Trust Centre for Neuroimaging, Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Hui Zhang
- Department of Computer Science and Centre for Medical Image ComputingUniversity College LondonLondonUnited Kingdom
| | | |
Collapse
|
12
|
Alpaugh M, Galleguillos D, Forero J, Morales LC, Lackey SW, Kar P, Di Pardo A, Holt A, Kerr BJ, Todd KG, Baker GB, Fouad K, Sipione S. Disease-modifying effects of ganglioside GM1 in Huntington's disease models. EMBO Mol Med 2018; 9:1537-1557. [PMID: 28993428 PMCID: PMC5666311 DOI: 10.15252/emmm.201707763] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by motor, cognitive and psychiatric problems. Previous studies indicated that levels of brain gangliosides are lower than normal in HD models and that administration of exogenous ganglioside GM1 corrects motor dysfunction in the YAC128 mouse model of HD In this study, we provide evidence that intraventricular administration of GM1 has profound disease-modifying effects across HD mouse models with different genetic background. GM1 administration results in decreased levels of mutant huntingtin, the protein that causes HD, and in a wide array of beneficial effects that include changes in levels of DARPP32, ferritin, Iba1 and GFAP, modulation of dopamine and serotonin metabolism, and restoration of normal levels of glutamate, GABA, L-Ser and D-Ser. Treatment with GM1 slows down neurodegeneration, white matter atrophy and body weight loss in R6/2 mice. Motor functions are significantly improved in R6/2 mice and restored to normal in Q140 mice, including gait abnormalities that are often resistant to treatments. Psychiatric-like and cognitive dysfunctions are also ameliorated by GM1 administration in Q140 and YAC128 mice. The widespread benefits of GM1 administration, at molecular, cellular and behavioural levels, indicate that this ganglioside has strong therapeutic and disease-modifying potential in HD.
Collapse
Affiliation(s)
- Melanie Alpaugh
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Danny Galleguillos
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Juan Forero
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada
| | | | | | - Preeti Kar
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Alba Di Pardo
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Andrew Holt
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Bradley J Kerr
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, AB, Canada
| | - Kathryn G Todd
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Glen B Baker
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Karim Fouad
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.,Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada
| | - Simonetta Sipione
- Department of Pharmacology, University of Alberta, Edmonton, AB, Canada .,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
13
|
Wu D, Faria AV, Younes L, Mori S, Brown T, Johnson H, Paulsen JS, Ross CA, Miller MI. Mapping the order and pattern of brain structural MRI changes using change-point analysis in premanifest Huntington's disease. Hum Brain Mapp 2017; 38:5035-5050. [PMID: 28657159 PMCID: PMC5766002 DOI: 10.1002/hbm.23713] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 06/12/2017] [Accepted: 06/19/2017] [Indexed: 02/02/2023] Open
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder that progressively affects motor, cognitive, and emotional functions. Structural MRI studies have demonstrated brain atrophy beginning many years prior to clinical onset ("premanifest" period), but the order and pattern of brain structural changes have not been fully characterized. In this study, we investigated brain regional volumes and diffusion tensor imaging (DTI) measurements in premanifest HD, and we aim to determine (1) the extent of MRI changes in a large number of structures across the brain by atlas-based analysis, and (2) the initiation points of structural MRI changes in these brain regions. We adopted a novel multivariate linear regression model to detect the inflection points at which the MRI changes begin (namely, "change-points"), with respect to the CAG-age product (CAP, an indicator of extent of exposure to the effects of CAG repeat expansion). We used approximately 300 T1-weighted and DTI data from premanifest HD and control subjects in the PREDICT-HD study, with atlas-based whole brain segmentation and change-point analysis. The results indicated a distinct topology of structural MRI changes: the change-points of the volumetric measurements suggested a central-to-peripheral pattern of atrophy from the striatum to the deep white matter; and the change points of DTI measurements indicated the earliest changes in mean diffusivity in the deep white matter and posterior white matter. While interpretation needs to be cautious given the cross-sectional nature of the data, these findings suggest a spatial and temporal pattern of spread of structural changes within the HD brain. Hum Brain Mapp 38:5035-5050, 2017. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Dan Wu
- The Russell H. Morgan Department of Radiology and Radiological ScienceJohns Hopkins University School of MedicineBaltimoreMaryland
| | - Andreia V. Faria
- The Russell H. Morgan Department of Radiology and Radiological ScienceJohns Hopkins University School of MedicineBaltimoreMaryland
| | - Laurent Younes
- Center for Imaging Science, Johns Hopkins UniversityBaltimoreMaryland
- Institute for Computational Medicine, Johns Hopkins UniversityBaltimoreMaryland
- Department of Applied Mathematics and StatisticsJohns Hopkins UniversityBaltimoreMaryland
| | - Susumu Mori
- The Russell H. Morgan Department of Radiology and Radiological ScienceJohns Hopkins University School of MedicineBaltimoreMaryland
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger InstituteBaltimoreMaryland
| | - Timothy Brown
- Center for Imaging Science, Johns Hopkins UniversityBaltimoreMaryland
| | - Hans Johnson
- Department of Electrical and Computer EngineeringUniversity of IowaIowa CityIowa
| | - Jane S. Paulsen
- Departments of Psychiatry, Neurology, Psychology and NeurosciencesUniversity of IowaIowa CityIowa
| | - Christopher A. Ross
- Division of Neurobiology, Departments of Psychiatry, Neurology, Neuroscience and Pharmacology, and Program in Cellular and Molecular MedicineJohns Hopkins University School of MedicineBaltimoreMaryland
| | - Michael I. Miller
- Center for Imaging Science, Johns Hopkins UniversityBaltimoreMaryland
- Institute for Computational Medicine, Johns Hopkins UniversityBaltimoreMaryland
- Department of Biomedical EngineeringJohns Hopkins UniversityBaltimoreMaryland
| | | |
Collapse
|
14
|
McColgan P, Seunarine KK, Gregory S, Razi A, Papoutsi M, Long JD, Mills JA, Johnson E, Durr A, Roos RA, Leavitt BR, Stout JC, Scahill RI, Clark CA, Rees G, Tabrizi SJ. Topological length of white matter connections predicts their rate of atrophy in premanifest Huntington's disease. JCI Insight 2017; 2:92641. [PMID: 28422761 PMCID: PMC5396531 DOI: 10.1172/jci.insight.92641] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/16/2017] [Indexed: 12/11/2022] Open
Abstract
We lack a mechanistic explanation for the stereotyped pattern of white matter loss seen in Huntington’s disease (HD). While the earliest white matter changes are seen around the striatum, within the corpus callosum, and in the posterior white matter tracts, the order in which these changes occur and why these white matter connections are specifically vulnerable is unclear. Here, we use diffusion tractography in a longitudinal cohort of individuals yet to develop clinical symptoms of HD to identify a hierarchy of vulnerability, where the topological length of white matter connections between a brain area and its neighbors predicts the rate of atrophy over 24 months. This demonstrates a new principle underlying neurodegeneration in HD, whereby brain connections with the greatest topological length are the first to suffer damage that can account for the stereotyped pattern of white matter loss observed in premanifest HD. Diffusion tractography in a longitudinal cohort demonstrates that topological length of white matter connections can account for white matter loss patterns in premanifest Huntington’s disease.
Collapse
Affiliation(s)
- Peter McColgan
- Huntington's Disease Centre, Department of Neurodegenerative Disease
| | - Kiran K Seunarine
- Developmental Imaging and Biophysics Section, UCL Institute of Child Health, London, United Kingdom
| | - Sarah Gregory
- Huntington's Disease Centre, Department of Neurodegenerative Disease
| | - Adeel Razi
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, London, United Kingdom.,Department of Electronic Engineering, NED University of Engineering and Technology, Karachi, Pakistan
| | - Marina Papoutsi
- Huntington's Disease Centre, Department of Neurodegenerative Disease
| | - Jeffrey D Long
- Department of Psychiatry.,Department of Biostatistics, University of Iowa, Iowa City, Iowa, USA
| | | | - Eileanoir Johnson
- Huntington's Disease Centre, Department of Neurodegenerative Disease
| | - Alexandra Durr
- APHP Department of Genetics, University Hospital Pitié-Salpêtrière, and ICM (Brain and Spine Institute) INSERM U1127, CNRS UMR7225, Sorbonne Universités - UPMC Paris VI UMR_S1127, Paris, France
| | - Raymund Ac Roos
- Department of Neurology, Leiden University Medical Centre, Leiden, Netherlands
| | - Blair R Leavitt
- Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, University of British Columbia, Vancouver British Columbia, Canada
| | - Julie C Stout
- School of Psychological Sciences, Monash University, Australia
| | - Rachael I Scahill
- Huntington's Disease Centre, Department of Neurodegenerative Disease
| | - Chris A Clark
- Developmental Imaging and Biophysics Section, UCL Institute of Child Health, London, United Kingdom
| | - Geraint Rees
- Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, London, United Kingdom
| | - Sarah J Tabrizi
- Huntington's Disease Centre, Department of Neurodegenerative Disease.,National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | -
- The Track-On HD Investigators are detailed in the Supplemental Acknowledgments
| |
Collapse
|
15
|
Son AI, Fu X, Suto F, Liu JS, Hashimoto-Torii K, Torii M. Proteome dynamics during postnatal mouse corpus callosum development. Sci Rep 2017; 7:45359. [PMID: 28349996 PMCID: PMC5368975 DOI: 10.1038/srep45359] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 02/27/2017] [Indexed: 02/08/2023] Open
Abstract
Formation of cortical connections requires the precise coordination of numerous discrete phases. This is particularly significant with regard to the corpus callosum, whose development undergoes several dynamic stages including the crossing of axon projections, elimination of exuberant projections, and myelination of established tracts. To comprehensively characterize the molecular events in this dynamic process, we set to determine the distinct temporal expression of proteins regulating the formation of the corpus callosum and their respective developmental functions. Mass spectrometry-based proteomic profiling was performed on early postnatal mouse corpus callosi, for which limited evidence has been obtained previously, using stable isotope of labeled amino acids in mammals (SILAM). The analyzed corpus callosi had distinct proteomic profiles depending on age, indicating rapid progression of specific molecular events during this period. The proteomic profiles were then segregated into five separate clusters, each with distinct trajectories relevant to their intended developmental functions. Our analysis both confirms many previously-identified proteins in aspects of corpus callosum development, and identifies new candidates in understudied areas of development including callosal axon refinement. We present a valuable resource for identifying new proteins integral to corpus callosum development that will provide new insights into the development and diseases afflicting this structure.
Collapse
Affiliation(s)
- Alexander I Son
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA
| | - Xiaoqin Fu
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA
| | - Fumikazu Suto
- Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo 187-8502, Japan
| | - Judy S Liu
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA.,Department of Pediatrics, Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20052, USA
| | - Kazue Hashimoto-Torii
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA.,Department of Pediatrics, Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20052, USA.,Department of Neurobiology and Kavli Institute for Neuroscience, School of Medicine, Yale University, New Haven, CT 06510, USA
| | - Masaaki Torii
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, DC 20010, USA.,Department of Pediatrics, Pharmacology and Physiology, School of Medicine and Health Sciences, The George Washington University, Washington, DC 20052, USA.,Department of Neurobiology and Kavli Institute for Neuroscience, School of Medicine, Yale University, New Haven, CT 06510, USA
| |
Collapse
|
16
|
Meng Y, Jiang J, Bachevalier J, Zhang X, Chan AWS. Developmental Whole Brain White Matter Alterations in Transgenic Huntington's Disease Monkey. Sci Rep 2017; 7:379. [PMID: 28336929 PMCID: PMC5428287 DOI: 10.1038/s41598-017-00381-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 02/23/2017] [Indexed: 11/17/2022] Open
Abstract
Transgenic Huntington’s disease monkey (HD monkey) model provides great opportunity for studying disease progression that could lead to new insight for developing biomarker, early intervention and novel therapeutics. Whole brain white matter integrity of HD-monkeys was examined longitudinally from 6 to 48 months using diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS). Progressive developmental white matter alterations in HD monkeys were widespread and were observed not only in fiber bundles connecting cortical areas to the striatum (e.g. striatal bundle and external capsule), but also in long association fiber pathways, commissural fibers, and subcortical fiber bundle. In all fiber tracts, the data indicate an arrest in white matter development around 23 months followed by slight decline until adulthood in HD monkeys. The microstructural changes parallel the progressive motor, memory and cognitive decline previously reported as HD monkeys aged. The findings revealed the widespread progressive temporal-spatial microstructural changes in HD monkey brains from infancy to adulthood, suggesting differentiated degenerations across different brain areas during brain development.
Collapse
Affiliation(s)
- Yuguang Meng
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Jie Jiang
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA.,Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA
| | - Jocelyne Bachevalier
- Department of Psychology, Emory University School of Medicine, Atlanta, Georgia, USA. .,Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA.
| | - Xiaodong Zhang
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA. .,Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA.
| | - Anthony W S Chan
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA. .,Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA.
| |
Collapse
|
17
|
The Complexity of Clinical Huntington's Disease: Developments in Molecular Genetics, Neuropathology and Neuroimaging Biomarkers. ADVANCES IN NEUROBIOLOGY 2017; 15:129-161. [PMID: 28674980 DOI: 10.1007/978-3-319-57193-5_5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder characterised by extensive neuronal loss in the striatum and cerebral cortex, and a triad of clinical symptoms affecting motor, cognitive/behavioural and mood functioning. The mutation causing HD is an expansion of a CAG tract in exon 1 of the HTT gene. This chapter provides a multifaceted overview of the clinical complexity of HD. We explore recent directions in molecular genetics including the identification of loci that are genetic modifiers of HD that could potentially reveal therapeutic targets beyond the HTT gene transcript and protein. The variability of clinical symptomatology in HD is considered alongside recent findings of variability in cellular and neurochemical changes in the striatum and cerebral cortex in human brain. We review evidence from structural neuroimaging methods of progressive changes of striatum, cerebral cortex and white matter in pre-symptomatic and symptomatic HD, with a particular focus on the potential identification of neuroimaging biomarkers that could be used to test promising disease-specific and modifying treatments. Finally we provide an overview of completed clinical trials in HD and future therapeutic developments.
Collapse
|
18
|
Scahill RI, Andre R, Tabrizi SJ, Aylward EH. Structural imaging in premanifest and manifest Huntington disease. HANDBOOK OF CLINICAL NEUROLOGY 2017; 144:247-261. [PMID: 28947121 DOI: 10.1016/b978-0-12-801893-4.00020-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Huntington disease (HD) neuropathology has a devastating effect on brain structure and consequently brain function; neuroimaging provides a means to assess these effects in gene carriers. In this chapter we first outline the unique utility of structural imaging in understanding HD and discuss some of the acquisition and analysis techniques currently available. We review the existing literature to summarize what we know so far about structural brain changes across the spectrum of disease from premanifest through to manifest disease. We then consider how these neuroimaging findings relate to patient function and nonimaging biomarkers, and can be used to predict disease onset. Finally we review the utility of imaging measures for assessment of treatment efficacy in clinical trials.
Collapse
Affiliation(s)
- Rachael I Scahill
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Ralph Andre
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, United Kingdom
| | - Sarah J Tabrizi
- Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London, United Kingdom.
| | - Elizabeth H Aylward
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington, Seattle, WA, United States
| |
Collapse
|
19
|
Harrington DL, Long JD, Durgerian S, Mourany L, Koenig K, Bonner-Jackson A, Paulsen JS, Rao SM. Cross-sectional and longitudinal multimodal structural imaging in prodromal Huntington's disease. Mov Disord 2016; 31:1664-1675. [PMID: 27620011 DOI: 10.1002/mds.26803] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/17/2016] [Accepted: 08/22/2016] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVES Diffusivity in white-matter tracts is abnormal throughout the brain in cross-sectional studies of prodromal Huntington's disease. To date, longitudinal changes have not been observed. The present study investigated cross-sectional and longitudinal changes in white-matter diffusivity in relationship to the phase of prodromal Huntington's progression, and compared them with changes in brain volumes and clinical variables that track disease progression. METHODS Diffusion MRI profiles were studied for 2 years in 37 gene-negative controls and 64 prodromal Huntington's disease participants in varied phases of disease progression. To estimate the relative importance of diffusivity metrics in the prodromal phase, group effects were rank ordered relative to those obtained from analyses of brain volumes, motor, cognitive, and sensory variables. RESULTS First, at baseline diffusivity was abnormal throughout all tracts, especially as individuals approached a manifest Huntington's disease diagnosis. Baseline diffusivity metrics in 6 tracts and basal ganglia volumes best distinguished among the groups. Second, group differences in longitudinal change in diffusivity were localized to the superior fronto-occipital fasciculus, most prominently in individuals closer to a diagnosis. Group differences were also observed in longitudinal changes of most brain volumes, but not clinical variables. Last, increases in motor symptoms across time were associated with greater changes in the superior fronto-occipital fasciculus diffusivity and corpus callosum, cerebrospinal fluid, and lateral ventricle volumes. CONCLUSIONS These novel findings provide new insights into changes within 2 years in different facets of brain structure and their clinical relevance to changes in symptomatology that is decisive for a manifest Huntington's diagnosis. © 2016 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Deborah L Harrington
- Department of Radiology, University of California, San Diego, La Jolla, California, USA.,Research Service, Veteran's Affairs San Diego Healthcare System, San Diego, California, USA
| | - Jeffrey D Long
- Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Sally Durgerian
- Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Lyla Mourany
- Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Katherine Koenig
- Imaging Sciences, Imaging Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Aaron Bonner-Jackson
- Lou Ruvo Center for Brain Health, Neurological Institute, Cleveland Clinic, Ohio, USA
| | - Jane S Paulsen
- Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | | | - Stephen M Rao
- Schey Center for Cognitive Neuroimaging, Neurological Institute, Cleveland Clinic, Cleveland, Ohio, USA
| |
Collapse
|
20
|
Reginold W, Itorralba J, Luedke AC, Fernandez-Ruiz J, Reginold J, Islam O, Garcia A. Tractography at 3T MRI of Corpus Callosum Tracts Crossing White Matter Hyperintensities. AJNR Am J Neuroradiol 2016; 37:1617-22. [PMID: 27127001 DOI: 10.3174/ajnr.a4788] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 02/16/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The impact of white matter hyperintensities on the diffusion characteristics of crossing tracts is unclear. This study used quantitative tractography at 3T MR imaging to compare, in the same individuals, the diffusion characteristics of corpus callosum tracts that crossed white matter hyperintensities with the diffusion characteristics of corpus callosum tracts that did not pass through white matter hyperintensities. MATERIALS AND METHODS Brain T2 fluid-attenuated inversion recovery-weighted and diffusion tensor 3T MR imaging scans were acquired in 24 individuals with white matter hyperintensities. Tractography data were generated by the Fiber Assignment by Continuous Tracking method. White matter hyperintensities and corpus callosum tracts were manually segmented. In the corpus callosum, the fractional anisotropy, radial diffusivity, and mean diffusivity of tracts crossing white matter hyperintensities were compared with the fractional anisotropy, radial diffusivity, and mean diffusivity of tracts that did not cross white matter hyperintensities. The cingulum, long association fibers, corticospinal/bulbar tracts, and thalamic projection fibers were included for comparison. RESULTS Within the corpus callosum, tracts that crossed white matter hyperintensities had decreased fractional anisotropy compared with tracts that did not pass through white matter hyperintensities (P = .002). Within the cingulum, tracts that crossed white matter hyperintensities had increased radial diffusivity compared with tracts that did not pass through white matter hyperintensities (P = .001). CONCLUSIONS In the corpus callosum and cingulum, tracts had worse diffusion characteristics when they crossed white matter hyperintensities. These results support a role for white matter hyperintensities in the disruption of crossing tracts.
Collapse
Affiliation(s)
- W Reginold
- From the Departments of Medical Imaging (W.R.) Memory Clinics (W.R., A.G.), Division of Geriatric Medicine, Department of Medicine
| | - J Itorralba
- Centre for Neuroscience Studies (J.I., A.G., A.C.L.), Queen's University, Kingston, Ontario, Canada
| | - A C Luedke
- Centre for Neuroscience Studies (J.I., A.G., A.C.L.), Queen's University, Kingston, Ontario, Canada
| | - J Fernandez-Ruiz
- Facultad de Medicina, (J.F.-R.), Universidad Nacional Autonoma de Mexico, Coyoacán, Mexico
| | - J Reginold
- Life Sciences (J.R.), University of Toronto, Toronto, Ontario, Canada
| | - O Islam
- Department of Diagnostic Radiology (O.I.), Kingston General Hospital, Queen's University, Kingston, Ontario, Canada
| | - A Garcia
- Memory Clinics (W.R., A.G.), Division of Geriatric Medicine, Department of Medicine Centre for Neuroscience Studies (J.I., A.G., A.C.L.), Queen's University, Kingston, Ontario, Canada
| |
Collapse
|
21
|
Faria AV, Ratnanather JT, Tward DJ, Lee DS, van den Noort F, Wu D, Brown T, Johnson H, Paulsen JS, Ross CA, Younes L, Miller MI. Linking white matter and deep gray matter alterations in premanifest Huntington disease. Neuroimage Clin 2016; 11:450-460. [PMID: 27104139 PMCID: PMC4827723 DOI: 10.1016/j.nicl.2016.02.014] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 02/17/2016] [Accepted: 02/22/2016] [Indexed: 01/07/2023]
Abstract
Huntington disease (HD) is a fatal progressive neurodegenerative disorder for which only symptomatic treatment is available. A better understanding of the pathology, and identification of biomarkers will facilitate the development of disease-modifying treatments. HD is potentially a good model of a neurodegenerative disease for development of biomarkers because it is an autosomal-dominant disease with complete penetrance, caused by a single gene mutation, in which the neurodegenerative process can be assessed many years before onset of signs and symptoms of manifest disease. Previous MRI studies have detected abnormalities in gray and white matter starting in premanifest stages. However, the understanding of how these abnormalities are related, both in time and space, is still incomplete. In this study, we combined deep gray matter shape diffeomorphometry and white matter DTI analysis in order to provide a better mapping of pathology in the deep gray matter and subcortical white matter in premanifest HD. We used 296 MRI scans from the PREDICT-HD database. Atrophy in the deep gray matter, thalamus, hippocampus, and nucleus accumbens was analyzed by surface based morphometry, and while white matter abnormalities were analyzed in (i) regions of interest surrounding these structures, using (ii) tractography-based analysis, and using (iii) whole brain atlas-based analysis. We detected atrophy in the deep gray matter, particularly in putamen, from early premanifest stages. The atrophy was greater both in extent and effect size in cases with longer exposure to the effects of the CAG expansion mutation (as assessed by greater CAP-scores), and preceded detectible abnormalities in the white matter. Near the predicted onset of manifest HD, the MD increase was widespread, with highest indices in the deep and posterior white matter. This type of in-vivo macroscopic mapping of HD brain abnormalities can potentially indicate when and where therapeutics could be targeted to delay the onset or slow the disease progression.
Collapse
Affiliation(s)
- Andreia V Faria
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - J Tilak Ratnanather
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
| | - Daniel J Tward
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
| | - David Soobin Lee
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
| | - Frieda van den Noort
- MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Dan Wu
- The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Timothy Brown
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA
| | - Hans Johnson
- Department of Psychiatry, The University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Jane S Paulsen
- Department of Psychiatry, The University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Christopher A Ross
- Division of Neurobiology, Department of Psychiatry, and Departments of Neurology, Neuroscience and Pharmacology, Johns Hopkins University, Baltimore, MD, USA
| | - Laurent Younes
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, USA; Department of Applied Mathematics and Statistics, The Johns Hopkins University, Baltimore, MD, USA
| | - Michael I Miller
- Center for Imaging Science, The Johns Hopkins University, Baltimore, MD, USA; Institute for Computational Medicine, The Johns Hopkins University, Baltimore, MD, USA; Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
22
|
Gregory S, Cole JH, Farmer RE, Rees EM, Roos RA, Sprengelmeyer R, Durr A, Landwehrmeyer B, Zhang H, Scahill RI, Tabrizi SJ, Frost C, Hobbs NZ. Longitudinal Diffusion Tensor Imaging Shows Progressive Changes in White Matter in Huntington’s Disease. J Huntingtons Dis 2015; 4:333-46. [DOI: 10.3233/jhd-150173] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Sarah Gregory
- Wellcome Trust Centre for Neuroimaging, UCL, London, WC1N 3BG, UK
| | - James H. Cole
- UCL Institute of Neurology, University College London, UK
- Computational, Cognitive & Clinical Neuroimaging Laboratory, Department of Medicine, Imperial College London, UK
| | - Ruth E. Farmer
- Department of Medical Statistics, London School of Hygiene & Tropical Medicine London, UK
| | - Elin M. Rees
- UCL Institute of Neurology, University College London, UK
| | - Raymund A.C. Roos
- Department of Neurology, Leiden University Medical Centre, 2300RC Leiden, The Netherlands
| | | | - Alexandra Durr
- Department of Genetics and Cytogenetics, INSERM UMR S679, APHP Hôpital de la Salpêtrière, Paris, France
| | | | - Hui Zhang
- Centre for Medical Image Computing, University College London, UK
| | | | | | - Chris Frost
- Department of Medical Statistics, London School of Hygiene & Tropical Medicine London, UK
| | - Nicola Z. Hobbs
- UCL Institute of Neurology, University College London, UK
- IXICO Plc., London, UK
| |
Collapse
|
23
|
Ross CA, Aylward EH, Wild EJ, Langbehn DR, Long JD, Warner JH, Scahill RI, Leavitt BR, Stout JC, Paulsen JS, Reilmann R, Unschuld PG, Wexler A, Margolis RL, Tabrizi SJ. Huntington disease: natural history, biomarkers and prospects for therapeutics. Nat Rev Neurol 2014; 10:204-16. [PMID: 24614516 DOI: 10.1038/nrneurol.2014.24] [Citation(s) in RCA: 659] [Impact Index Per Article: 65.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Huntington disease (HD) can be seen as a model neurodegenerative disorder, in that it is caused by a single genetic mutation and is amenable to predictive genetic testing, with estimation of years to predicted onset, enabling the entire range of disease natural history to be studied. Structural neuroimaging biomarkers show that progressive regional brain atrophy begins many years before the emergence of diagnosable signs and symptoms of HD, and continues steadily during the symptomatic or 'manifest' period. The continued development of functional, neurochemical and other biomarkers raises hopes that these biomarkers might be useful for future trials of disease-modifying therapeutics to delay the onset and slow the progression of HD. Such advances could herald a new era of personalized preventive therapeutics. We describe the natural history of HD, including the timing of emergence of motor, cognitive and emotional impairments, and the techniques that are used to assess these features. Building on this information, we review recent progress in the development of biomarkers for HD, and potential future roles of these biomarkers in clinical trials.
Collapse
Affiliation(s)
- Christopher A Ross
- Division of Neurobiology, Johns Hopkins University, 600 North Wolfe Street, Baltimore, MD 21287, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | - Russell L Margolis
- Division of Neurobiology, Johns Hopkins University, 600 North Wolfe Street, Baltimore, MD 21287, USA
| | | |
Collapse
|