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Hensman Moss DJ, Robertson N, Farmer R, Scahill RI, Haider S, Tessari MA, Flynn G, Fischer DF, Wild EJ, Macdonald D, Tabrizi SJ. Quantification of huntingtin protein species in Huntington's disease patient leukocytes using optimised electrochemiluminescence immunoassays. PLoS One 2017; 12:e0189891. [PMID: 29272284 PMCID: PMC5741241 DOI: 10.1371/journal.pone.0189891] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 12/01/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Huntington's disease (HD) is an autosomal dominant neurodegenerative condition caused by an expanded CAG repeat in the gene encoding huntingtin (HTT). Optimizing peripheral quantification of huntingtin throughout the course of HD is valuable not only to illuminate the natural history and pathogenesis of disease, but also to detect peripheral effects of drugs in clinical trial. RATIONALE We previously demonstrated that mutant HTT (mHTT) was significantly elevated in purified HD patient leukocytes compared with controls and that these levels track disease progression. Our present study investigates whether the same result can be achieved with a simpler and more scalable collection technique that is more suitable for clinical trials. METHODS We collected whole blood at 133 patient visits in two sample sets and generated peripheral blood mononuclear cells (PBMCs). Levels of mHTT, as well as N-, and C-terminal and mid-region huntingtin were measured in the PBMCs using ELISA-based Meso Scale Discovery (MSD) electrochemiluminescence immunoassay platforms, and we evaluated the relationship between different HTT species, disease stage, and brain atrophy on magnetic resonance imaging. CONCLUSIONS The assays were sensitive and accurate. We confirm our previous findings that mHTT increases with advancing disease stage in patient PBMCs, this time using a simple collection protocol and scalable assay.
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Long JD, Mills JA, Leavitt BR, Durr A, Roos RA, Stout JC, Reilmann R, Landwehrmeyer B, Gregory S, Scahill RI, Langbehn DR, Tabrizi SJ. Survival End Points for Huntington Disease Trials Prior to a Motor Diagnosis. JAMA Neurol 2017; 74:1352-1360. [PMID: 28975278 PMCID: PMC5710578 DOI: 10.1001/jamaneurol.2017.2107] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 06/13/2017] [Indexed: 01/29/2023]
Abstract
Importance Predictive genetic testing in Huntington disease (HD) enables therapeutic trials in HTT gene expansion mutation carriers prior to a motor diagnosis. Progression-free survival (PFS) is the composite of a motor diagnosis or a progression event, whichever comes first. Objective To determine if PFS provides feasible sample sizes for trials with mutation carriers who have not yet received a motor diagnosis. Design, Setting, and Participants This study uses data from the 2-phase, longitudinal cohort studies called Track and from a longitudinal cohort study called the Cooperative Huntington Observational Research Trial (COHORT). Track had 167 prediagnosis mutation carriers and 156 noncarriers, whereas COHORT had 366 prediagnosis mutation carriers and noncarriers. Track studies were conducted at 4 sites in 4 countries (Canada, France, England, and the Netherlands) from which data were collected from January 17, 2008, through November 17, 2014. The COHORT was conducted at 38 sites in 3 countries (Australia, Canada, and the United States) from which data were collected from February 14, 2006, through December 31, 2009. Results from the Track data were externally validated with data from the COHORT. The required sample size was estimated for a 2-arm prediagnosis clinical trial. Data analysis took place from May 1, 2016, to June 10, 2017. Main Outcomes and Measures The primary end point is PFS. Huntington disease progression events are defined for the Unified Huntington's Disease Rating Scale total motor score, total functional capacity, symbol digit modalities test, and Stroop word test. Results Of Track's 167 prediagnosis mutation carriers, 93 (55.6%) were women, and the mean (SD) age was 40.06 (8.92) years; of the 156 noncarriers, 87 (55.7%) were women, and the mean (SD) age was 45.58 (10.30) years. Of the 366 COHORT participants, 229 (62.5%) were women and the mean (SD) age was 42.21 (12.48) years. The PFS curves of the Track mutation carriers showed good external validity with the COHORT mutation carriers after adjusting for initial progression. For required sample size, PFS with a motor diagnosis or total motor score progression required about 4 times fewer participants than a motor diagnosis alone. Including additional cognitive progression events further reduced the number. For example, a 3-year trial with 10% attrition and a treatment effect of 50% requires a total of 661 with motor diagnosis as the survival end point but only 177 with a total motor score PFS. Conclusions and Relevance Reasonably sized prediagnosis Huntington disease trials can be planned with PFS, and there is evidence of generalizability of this approach.
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Frost C, Mulick A, Scahill RI, Owen G, Aylward E, Leavitt BR, Durr A, Roos RAC, Borowsky B, Stout JC, Reilmann R, Langbehn DR, Tabrizi SJ, Sampaio C. Design optimization for clinical trials in early-stage manifest Huntington's disease. Mov Disord 2017; 32:1610-1619. [PMID: 28906031 DOI: 10.1002/mds.27122] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 06/22/2017] [Accepted: 07/03/2017] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES The purpose of this study was to inform the design of randomized clinical trials in early-stage manifest Huntington's disease through analysis of longitudinal data from TRACK-Huntington's Disease (TRACK-HD), a multicenter observational study. METHODS We compute sample sizes required for trials with candidate clinical, functional, and imaging outcomes, whose aims are to reduce rates of change. The calculations use a 2-stage approach: first using linear mixed models to estimate mean rates of change and components of variability from TRACK-HD data and second using these to predict sample sizes for a range of trial designs. RESULTS For each outcome, the primary drivers of the required sample size were the anticipated treatment effect and the duration of treatment. Extending durations from 1 to 2 years yielded large sample size reductions. Including interim visits and incorporating stratified randomization on predictors of outcome together with covariate adjustment gave more modest, but nontrivial, benefits. Caudate atrophy, expressed as a percentage of its baseline, was the outcome that gave smallest required sample sizes. DISCUSSION Here we consider potential required sample sizes for clinical trials estimated from naturalistic observation of longitudinal change. Choice among outcome measures for a trial must additionally consider their relevance to patients and the expected effect of the treatment under study. For all outcomes considered, our results provide compelling arguments for 2-year trials, and we also demonstrate the benefits of incorporating stratified randomization coupled with covariate adjustment, particularly for trials with caudate atrophy as the primary outcome. The benefits of enrichment are more debatable, with statistical benefits offset by potential recruitment difficulties and reduced generalizability. © 2017 International Parkinson and Movement Disorder Society.
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Minkova L, Gregory S, Scahill RI, Abdulkadir A, Kaller CP, Peter J, Long JD, Stout JC, Reilmann R, Roos RA, Durr A, Leavitt BR, Tabrizi SJ, Klöppel S. Cross-sectional and longitudinal voxel-based grey matter asymmetries in Huntington's disease. Neuroimage Clin 2017; 17:312-324. [PMID: 29527479 PMCID: PMC5842644 DOI: 10.1016/j.nicl.2017.10.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 10/18/2017] [Accepted: 10/23/2017] [Indexed: 11/22/2022]
Abstract
Huntington's disease (HD) is a progressive neurodegenerative disorder that can be genetically confirmed with certainty decades before clinical onset. This allows the investigation of functional and structural changes in HD many years prior to disease onset, which may reveal important mechanistic insights into brain function, structure and organization in general. While regional atrophy is present at early stages of HD, it is still unclear if both hemispheres are equally affected by neurodegeneration and how the extent of asymmetry affects domain-specific functional decline. Here, we used whole-brain voxel-based analysis to investigate cross-sectional and longitudinal hemispheric asymmetries in grey matter (GM) volume in 56 manifest HD (mHD), 83 pre-manifest HD (preHD), and 80 healthy controls (HC). Furthermore, a regression analysis was used to assess the relationship between neuroanatomical asymmetries and decline in motor and cognitive measures across the disease spectrum. The cross-sectional analysis showed striatal leftward-biased GM atrophy in mHD, but not in preHD, relative to HC. Longitudinally, no net 36-month change in GM asymmetries was found in any of the groups. In the regression analysis, HD-related decline in quantitative-motor (Q-Motor) performance was linked to lower GM volume in the left superior parietal cortex. These findings suggest a stronger disease effect targeting the left hemisphere, especially in those with declining motor performance. This effect did not change over a period of three years and may indicate a compensatory role of the right hemisphere in line with recent functional imaging studies.
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Johnson EB, Gregory S, Johnson HJ, Durr A, Leavitt BR, Roos RA, Rees G, Tabrizi SJ, Scahill RI. Recommendations for the Use of Automated Gray Matter Segmentation Tools: Evidence from Huntington's Disease. Front Neurol 2017; 8:519. [PMID: 29066997 PMCID: PMC5641297 DOI: 10.3389/fneur.2017.00519] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 09/19/2017] [Indexed: 01/15/2023] Open
Abstract
The selection of an appropriate segmentation tool is a challenge facing any researcher aiming to measure gray matter (GM) volume. Many tools have been compared, yet there is currently no method that can be recommended above all others; in particular, there is a lack of validation in disease cohorts. This work utilizes a clinical dataset to conduct an extensive comparison of segmentation tools. Our results confirm that all tools have advantages and disadvantages, and we present a series of considerations that may be of use when selecting a GM segmentation method, rather than a ranking of these tools. Seven segmentation tools were compared using 3 T MRI data from 20 controls, 40 premanifest Huntington's disease (HD), and 40 early HD participants. Segmented volumes underwent detailed visual quality control. Reliability and repeatability of total, cortical, and lobular GM were investigated in repeated baseline scans. The relationship between each tool was also examined. Longitudinal within-group change over 3 years was assessed via generalized least squares regression to determine sensitivity of each tool to disease effects. Visual quality control and raw volumes highlighted large variability between tools, especially in occipital and temporal regions. Most tools showed reliable performance and the volumes were generally correlated. Results for longitudinal within-group change varied between tools, especially within lobular regions. These differences highlight the need for careful selection of segmentation methods in clinical neuroimaging studies. This guide acts as a primer aimed at the novice or non-technical imaging scientist providing recommendations for the selection of cohort-appropriate GM segmentation software.
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Byrne LM, Rodrigues FB, Blennow K, Durr A, Leavitt BR, Roos RAC, Scahill RI, Tabrizi SJ, Zetterberg H, Langbehn D, Wild EJ. Neurofilament light protein in blood as a potential biomarker of neurodegeneration in Huntington's disease: a retrospective cohort analysis. Lancet Neurol 2017; 16:601-609. [PMID: 28601473 PMCID: PMC5507767 DOI: 10.1016/s1474-4422(17)30124-2] [Citation(s) in RCA: 235] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND Blood biomarkers of neuronal damage could facilitate clinical management of and therapeutic development for Huntington's disease. We investigated whether neurofilament light protein NfL (also known as NF-L) in blood is a potential prognostic marker of neurodegeneration in patients with Huntington's disease. METHODS We did a retrospective analysis of healthy controls and carriers of CAG expansion mutations in HTT participating in the 3-year international TRACK-HD study. We studied associations between NfL concentrations in plasma and clinical and MRI neuroimaging findings, namely cognitive function, motor function, and brain volume (global and regional). We used random effects models to analyse cross-sectional associations at each study visit and to assess changes from baseline, with and without adjustment for age and CAG repeat count. In an independent London-based cohort of 37 participants (23 HTT mutation carriers and 14 controls), we further assessed whether concentrations of NfL in plasma correlated with those in CSF. FINDINGS Baseline and follow-up plasma samples were available from 97 controls and 201 individuals carrying HTT mutations. Mean concentrations of NfL in plasma at baseline were significantly higher in HTT mutation carriers than in controls (3·63 [SD 0·54] log pg/mL vs 2·68 [0·52] log pg/mL, p<0·0001) and the difference increased from one disease stage to the next. At any given timepoint, NfL concentrations in plasma correlated with clinical and MRI findings. In longitudinal analyses, baseline NfL concentration in plasma also correlated significantly with subsequent decline in cognition (symbol-digit modality test r=-0·374, p<0·0001; Stroop word reading r=-0·248, p=0·0033), total functional capacity (r=-0·289, p=0·0264), and brain atrophy (caudate r=0·178, p=0·0087; whole-brain r=0·602, p<0·0001; grey matter r=0·518, p<0·0001; white matter r=0·588, p<0·0001; and ventricular expansion r=-0·589, p<0·0001). All changes except Stroop word reading and total functional capacity remained significant after adjustment for age and CAG repeat count. In 104 individuals with premanifest Huntington's disease, NfL concentration in plasma at baseline was associated with subsequent clinical onset during the 3-year follow-up period (hazard ratio 3·29 per log pg/mL, 95% CI 1·48-7·34, p=0·0036). Concentrations of NfL in CSF and plasma were correlated in mutation carriers (r=0·868, p<0·0001). INTERPRETATION NfL in plasma shows promise as a potential prognostic blood biomarker of disease onset and progression in Huntington's disease. FUNDING Medical Research Council, GlaxoSmithKline, CHDI Foundation, Swedish Research Council, European Research Council, Wallenberg Foundation, and Wolfson Foundation.
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McColgan P, Razi A, Gregory S, Seunarine KK, Durr A, A.C. Roos R, Leavitt BR, Scahill RI, Clark CA, Langbehn DR, Rees G, Tabrizi SJ. Structural and functional brain network correlates of depressive symptoms in premanifest Huntington's disease. Hum Brain Mapp 2017; 38:2819-2829. [PMID: 28294457 PMCID: PMC5434856 DOI: 10.1002/hbm.23527] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/25/2016] [Accepted: 12/15/2016] [Indexed: 12/19/2022] Open
Abstract
Depression is common in premanifest Huntington's disease (preHD) and results in significant morbidity. We sought to examine how variations in structural and functional brain networks relate to depressive symptoms in premanifest HD and healthy controls. Brain networks were constructed using diffusion tractography (70 preHD and 81 controls) and resting state fMRI (92 preHD and 94 controls) data. A sub-network associated with depression was identified in a data-driven fashion and network-based statistics was used to investigate which specific connections correlated with depression scores. A replication analysis was then performed using data from a separate study. Correlations between depressive symptoms with increased functional connectivity and decreased structural connectivity were seen for connections in the default mode network (DMN) and basal ganglia in preHD. This study reveals specific connections in the DMN and basal ganglia that are associated with depressive symptoms in preHD. Hum Brain Mapp 38:2819-2829, 2017. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.
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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.
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Gregory S, Long JD, Klöppel S, Razi A, Scheller E, Minkova L, Papoutsi M, Mills JA, Durr A, Leavitt BR, Roos RAC, Stout JC, Scahill RI, Langbehn DR, Tabrizi SJ, Rees G. Operationalizing compensation over time in neurodegenerative disease. Brain 2017; 140:1158-1165. [PMID: 28334888 PMCID: PMC5382953 DOI: 10.1093/brain/awx022] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 10/26/2016] [Accepted: 12/21/2016] [Indexed: 12/22/2022] Open
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McColgan P, Gregory S, Razi A, Seunarine KK, Gargouri F, Durr A, Roos RAC, Leavitt BR, Scahill RI, Clark CA, Tabrizi SJ, Rees G, Coleman A, Decolongon J, Fan M, Petkau T, Jauffret C, Justo D, Lehericy S, Nigaud K, Valabrègue R, Choonderbeek A, Hart EPT, Hensman Moss DJ, Crawford H, Johnson E, Papoutsi M, Berna C, Reilmann R, Weber N, Stout J, Labuschagne I, Landwehrmeyer B, Orth M, Johnson H. White matter predicts functional connectivity in premanifest Huntington's disease. Ann Clin Transl Neurol 2017; 4:106-118. [PMID: 28168210 PMCID: PMC5288460 DOI: 10.1002/acn3.384] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/22/2016] [Accepted: 11/28/2016] [Indexed: 02/01/2023] Open
Abstract
Objectives The distribution of pathology in neurodegenerative disease can be predicted by the organizational characteristics of white matter in healthy brains. However, we have very little evidence for the impact these pathological changes have on brain function. Understanding any such link between structure and function is critical for understanding how underlying brain pathology influences the progressive behavioral changes associated with neurodegeneration. Here, we demonstrate such a link between structure and function in individuals with premanifest Huntington's. Methods Using diffusion tractography and resting state functional magnetic resonance imaging to characterize white matter organization and functional connectivity, we investigate whether characteristic patterns of white matter organization in the healthy human brain shape the changes in functional coupling between brain regions in premanifest Huntington's disease. Results We find changes in functional connectivity in premanifest Huntington's disease that link directly to underlying patterns of white matter organization in healthy brains. Specifically, brain areas with strong structural connectivity show decreases in functional connectivity in premanifest Huntington's disease relative to controls, while regions with weak structural connectivity show increases in functional connectivity. Furthermore, we identify a pattern of dissociation in the strongest functional connections between anterior and posterior brain regions such that anterior functional connectivity increases in strength in premanifest Huntington's disease, while posterior functional connectivity decreases. Interpretation Our findings demonstrate that organizational principles of white matter underlie changes in functional connectivity in premanifest Huntington's disease. Furthermore, we demonstrate functional antero–posterior dissociation that is in keeping with the caudo–rostral gradient of striatal pathology in HD.
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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.
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Politis M, Lahiri N, Niccolini F, Su P, Wu K, Giannetti P, Scahill RI, Turkheimer FE, Tabrizi SJ, Piccini P. Corrigendum to "Increased central microglial activation associated with peripheral cytokine levels in premanifest Huntington's disease gene carriers" [Neurobiol. Dis. 83 (2015) 115-121]. Neurobiol Dis 2016; 98:162. [PMID: 27939917 DOI: 10.1016/j.nbd.2016.12.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Gregory S, Long JD, Klöppel S, Razi A, Scheller E, Minkova L, Papoutsi M, Mills JA, Stout J, Scahill RI, Langbehn DR, Tabrizi SJ, Rees G. D20 Operationalising compensation over time in neurodegenerative disease. J Neurol Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Johnson EB, Dürr A, Leavitt B, Roos RAC, Langbehn DR, Tabriz SJ, Scahill RI. D9 An evaluation of methods for the volumetric measurement of grey matter in huntington’s disease. J Neurol Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Gregory S, Klöppel S, Long JD, Razi A, Scheller E, Minkova L, Dürr A, Roos RAC, Leavitt BR, Mills JA, Stout J, Scahill RI, Langbehn DR, Rees G, Tabrizi SJ. D21 Longitudinal compensation in the cognitive network in huntington’s disease. J Neurol Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Crawford H, Langbehn DR, Scahill RI, Rees G, Tabrizi SJ, Orth M, Gregory S. D16 White matter microstructure and natural biological variation in huntington’s disease. J Neurol Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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McColgan P, Razi A, Seunarine KK, Gregory S, Durr A, Roos RAC, Scahill RI, Clark CA, Rees G, Tabrizi SJ. D18 Brain network breakdown and pathophysiological correlates in huntington’s disease. Journal of Neurology, Neurosurgery and Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Gregory S, Klöppel S, Scheller E, Minkova L, Razi A, Durr A, Roos RAC, Leavitt BR, Papoutsi M, Bernhard Landwehrmeyer G, Reilmann R, Borowsky B, Johnson H, Mills JA, Owen G, Stout J, Scahill RI, Long JD, Rees G, Tabrizi SJ. D22 Compensation in preclinical huntington’s disease: evidence from the track-on HD study. Journal of Neurology, Neurosurgery and Psychiatry 2016. [DOI: 10.1136/jnnp-2016-314597.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Orth M, Gregory S, Scahill RI, Mayer IS, Minkova L, Klöppel S, Seunarine KK, Boyd L, Borowsky B, Reilmann R, Bernhard Landwehrmeyer G, Leavitt BR, Roos RA, Durr A, Rees G, Rothwell JC, Langbehn D, Tabrizi SJ. Natural variation in sensory-motor white matter organization influences manifestations of Huntington's disease. Hum Brain Mapp 2016; 37:4615-4628. [PMID: 27477323 DOI: 10.1002/hbm.23332] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 07/19/2016] [Accepted: 07/22/2016] [Indexed: 12/31/2022] Open
Abstract
While the HTT CAG-repeat expansion mutation causing Huntington's disease (HD) is highly correlated with the rate of pathogenesis leading to disease onset, considerable variance in age-at-onset remains unexplained. Therefore, other factors must influence the pathogenic process. We asked whether these factors were related to natural biological variation in the sensory-motor system. In 243 participants (96 premanifest and 35 manifest HD; 112 controls), sensory-motor structural MRI, tractography, resting-state fMRI, electrophysiology (including SEP amplitudes), motor score ratings, and grip force as sensory-motor performance were measured. Following individual modality analyses, we used principal component analysis (PCA) to identify patterns associated with sensory-motor performance, and manifest versus premanifest HD discrimination. We did not detect longitudinal differences over 12 months. PCA showed a pattern of loss of caudate, grey and white matter volume, cortical thickness in premotor and sensory cortex, and disturbed diffusivity in sensory-motor white matter tracts that was connected to CAG repeat length. Two further major principal components appeared in controls and HD individuals indicating that they represent natural biological variation unconnected to the HD mutation. One of these components did not influence HD while the other non-CAG-driven component of axial versus radial diffusivity contrast in white matter tracts were associated with sensory-motor performance and manifest HD. The first component reflects the expected CAG expansion effects on HD pathogenesis. One non-CAG-driven component reveals an independent influence on pathogenesis of biological variation in white matter tracts and merits further investigation to delineate the underlying mechanism and the potential it offers for disease modification. Hum Brain Mapp 37:4615-4628, 2016. © 2016 Wiley Periodicals, Inc.
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Labuschagne I, Cassidy AM, Scahill RI, Johnson EB, Rees E, O'Regan A, Queller S, Frost C, Leavitt BR, Dürr A, Roos R, Owen G, Borowsky B, Tabrizi SJ, Stout JC. Visuospatial Processing Deficits Linked to Posterior Brain Regions in Premanifest and Early Stage Huntington's Disease. J Int Neuropsychol Soc 2016; 22:595-608. [PMID: 27211109 DOI: 10.1017/s1355617716000321] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVES Visuospatial processing deficits have been reported in Huntington's disease (HD). To date, no study has examined associations between visuospatial cognition and posterior brain findings in HD. METHODS We compared 119 premanifest (55> and 64<10.8 years to expected disease onset) and 104 early symptomatic (59 stage-1 and 45 stage-2) gene carriers, with 110 controls on visual search and mental rotation performance at baseline and 12 months. In the disease groups, we also examined associations between task performance and disease severity, functional capacity and structural brain measures. RESULTS Cross-sectionally, there were strong differences between all disease groups and controls on visual search, and between diagnosed groups and controls on mental rotation accuracy. Only the premanifest participants close to onset took longer than controls to respond correctly to mental rotation. Visual search negatively correlated with disease burden and motor symptoms in diagnosed individuals, and positively correlated with functional capacity. Mental rotation ("same") was negatively correlated with motor symptoms in stage-2 individuals, and positively correlated with functional capacity. Visual search and mental rotation were associated with parieto-occipital (pre-/cuneus, calcarine, lingual) and temporal (posterior fusiform) volume and cortical thickness. Longitudinally, visual search deteriorated over 12 months in stage-2 individuals, with no evidence of declines in mental rotation. CONCLUSIONS Our findings provide evidence linking early visuospatial deficits to functioning and posterior cortical dysfunction in HD. The findings are important since large research efforts have focused on fronto-striatal mediated cognitive changes, with little attention given to aspects of cognition outside of these areas. (JINS, 2016, 22, 595-608).
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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]
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Johnson EB, Rees EM, Labuschagne I, Durr A, Leavitt BR, Roos RAC, Reilmann R, Johnson H, Hobbs NZ, Langbehn DR, Stout JC, Tabrizi SJ, Scahill RI. The impact of occipital lobe cortical thickness on cognitive task performance: An investigation in Huntington's Disease. Neuropsychologia 2015; 79:138-46. [PMID: 26519555 DOI: 10.1016/j.neuropsychologia.2015.10.033] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 10/07/2015] [Accepted: 10/26/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND The occipital lobe is an important visual processing region of the brain. Following consistent findings of early neural changes in the occipital lobe in Huntington's Disease (HD), we examined cortical thickness across four occipital regions in premanifest (preHD) and early HD groups compared with controls. Associations between cortical thickness in gene positive individuals and performance on six cognitive tasks, each with a visual component, were examined. In addition, the association between cortical thickness in gene positive participants and one non-visual motor task was also examined for comparison. METHODS Cortical thickness was determined using FreeSurfer on T1-weighted 3T MR datasets from controls (N=97), preHD (N=109) and HD (N=69) from the TRACK-HD study. Regression models were fitted to assess between-group differences in cortical thickness, and relationships between performance on the cognitive tasks, the motor task and occipital thickness were examined in a subset of gene-positive participants (N=141). RESULTS Thickness of the occipital cortex in preHD and early HD participants was reduced compared with controls. Regionally-specific associations between reduced cortical thickness and poorer performance were found for five of the six cognitive tasks, with the strongest associations in lateral occipital and lingual regions. No associations were found with the cuneus. The non-visual motor task was not associated with thickness of any region. CONCLUSIONS The heterogeneous pattern of associations found in the present study suggests that occipital thickness negatively impacts cognition, but only in regions that are linked to relatively advanced visual processing (e.g., lateral occipital, lingual regions), rather than in basic visual processing regions such as the cuneus. Our results show, for the first time, the functional implications of occipital atrophy highlighted in recent studies in HD.
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Hobbs NZ, Farmer RE, Rees EM, Cole JH, Haider S, Malone IB, Sprengelmeyer R, Johnson H, Mueller HP, Sussmuth SD, Roos RAC, Durr A, Frost C, Scahill RI, Landwehrmeyer B, Tabrizi SJ. Short-interval observational data to inform clinical trial design in Huntington's disease. J Neurol Neurosurg Psychiatry 2015; 86:1291-8. [PMID: 25669748 DOI: 10.1136/jnnp-2014-309768] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 01/07/2015] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To evaluate candidate outcomes for disease-modifying trials in Huntington's disease (HD) over 6-month, 9-month and 15-month intervals, across multiple domains. To present guidelines on rapid efficacy readouts for disease-modifying trials. METHODS 40 controls and 61 patients with HD, recruited from four EU sites, underwent 3 T MRI and standard clinical and cognitive assessments at baseline, 6 and 15 months. Neuroimaging analysis included global and regional change in macrostructure (atrophy and cortical thinning), and microstructure (diffusion metrics). The main outcome was longitudinal effect size (ES) for each outcome. Such ESs can be used to calculate sample-size requirements for clinical trials for hypothesised treatment efficacies. RESULTS Longitudinal changes in macrostructural neuroimaging measures such as caudate atrophy and ventricular expansion were significantly larger in HD than controls, giving rise to consistently large ES over the 6-month, 9-month and 15-month intervals. Analogous ESs for cortical metrics were smaller with wide CIs. Microstructural (diffusion) neuroimaging metrics ESs were also typically smaller over the shorter intervals, although caudate diffusivity metrics performed strongly over 9 and 15 months. Clinical and cognitive outcomes exhibited small longitudinal ESs, particularly over 6-month and 9-month intervals, with wide CIs, indicating a lack of precision. CONCLUSIONS To exploit the potential power of specific neuroimaging measures such as caudate atrophy in disease-modifying trials, we propose their use as (1) initial short-term readouts in early phase/proof-of-concept studies over 6 or 9 months, and (2) secondary end points in efficacy studies over longer periods such as 15 months.
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Politis M, Lahiri N, Niccolini F, Su P, Wu K, Giannetti P, Scahill RI, Turkheimer FE, Tabrizi SJ, Piccini P. Increased central microglial activation associated with peripheral cytokine levels in premanifest Huntington's disease gene carriers. Neurobiol Dis 2015; 83:115-21. [PMID: 26297319 DOI: 10.1016/j.nbd.2015.08.011] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Revised: 07/19/2015] [Accepted: 08/12/2015] [Indexed: 01/27/2023] Open
Abstract
Previous studies have shown activation of the immune system and altered immune response in Huntington's disease (HD) gene carriers. Here, we hypothesized that peripheral and central immune responses could be concurrent pathophysiological events and represent a global innate immune response to the toxic effects of mutant huntingtin in HD gene carriers. We sought to investigate our hypothesis using [(11)C]PK11195 PET as a translocator protein (TSPO) marker of central microglial activation, together with assessment of peripheral plasma cytokine levels in a cohort of premanifest HD gene carriers who were more than a decade from predicted symptomatic conversion. Data were also compared to those from a group of healthy controls matched for age and gender. We found significantly increased peripheral plasma IL-1β levels in premanifest HD gene carriers compared to the group of normal controls (P=0.018). Premanifest HD gene carriers had increased TSPO levels in cortical, basal ganglia and thalamic brain regions (P<0.001). Increased microglial activation in somatosensory cortex correlated with higher plasma levels of IL-1β (rs=0.87, P=0.013), IL-6 (rs=0.85, P=0.013), IL-8 (rs=0.68, P=0.045) and TNF-α (rs=0.79; P=0.013). Our findings provide first in vivo evidence for an association between peripheral and central immune responses in premanifest HD gene carriers, and provide further supporting evidence for the role of immune dysfunction in the pathogenesis of HD.
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McColgan P, Seunarine KK, Razi A, Cole JH, Gregory S, Durr A, Roos RAC, Stout JC, Landwehrmeyer B, Scahill RI, Clark CA, Rees G, Tabrizi SJ. Selective vulnerability of Rich Club brain regions is an organizational principle of structural connectivity loss in Huntington's disease. Brain 2015; 138:3327-44. [PMID: 26384928 PMCID: PMC4620513 DOI: 10.1093/brain/awv259] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 07/21/2015] [Accepted: 07/22/2015] [Indexed: 01/05/2023] Open
Abstract
Huntington's disease can be predicted many years before symptom onset, and thus makes an ideal model for studying the earliest mechanisms of neurodegeneration. Diffuse patterns of structural connectivity loss occur in the basal ganglia and cortex early in the disease. However, the organizational principles that underlie these changes are unclear. By understanding such principles we can gain insight into the link between the cellular pathology caused by mutant huntingtin and its downstream effect at the macroscopic level. The 'rich club' is a pattern of organization established in healthy human brains, where specific hub 'rich club' brain regions are more highly connected to each other than other brain regions. We hypothesized that selective loss of rich club connectivity might represent an organizing principle underlying the distributed pattern of structural connectivity loss seen in Huntington's disease. To test this hypothesis we performed diffusion tractography and graph theoretical analysis in a pseudo-longitudinal study of 50 premanifest and 38 manifest Huntington's disease participants compared with 47 healthy controls. Consistent with our hypothesis we found that structural connectivity loss selectively affected rich club brain regions in premanifest and manifest Huntington's disease participants compared with controls. We found progressive network changes across controls, premanifest Huntington's disease and manifest Huntington's disease characterized by increased network segregation in the premanifest stage and loss of network integration in manifest disease. These regional and whole brain network differences were highly correlated with cognitive and motor deficits suggesting they have pathophysiological relevance. We also observed greater reductions in the connectivity of brain regions that have higher network traffic and lower clustering of neighbouring regions. This provides a potential mechanism that results in a characteristic pattern of structural connectivity loss targeting highly connected brain regions with high network traffic and low clustering of neighbouring regions. Our findings highlight the role of the rich club as a substrate for the structural connectivity loss seen in Huntington's disease and have broader implications for understanding the connection between molecular and systems level pathology in neurodegenerative disease.
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