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Tchetchenian A, Zekelman L, Chen Y, Rushmore J, Zhang F, Yeterian EH, Makris N, Rathi Y, Meijering E, Song Y, O'Donnell LJ. Deep multimodal saliency parcellation of cerebellar pathways: Linking microstructure and individual function through explainable multitask learning. Hum Brain Mapp 2024; 45:e70008. [PMID: 39185598 PMCID: PMC11345609 DOI: 10.1002/hbm.70008] [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: 01/29/2024] [Revised: 07/18/2024] [Accepted: 08/10/2024] [Indexed: 08/27/2024] Open
Abstract
Parcellation of human cerebellar pathways is essential for advancing our understanding of the human brain. Existing diffusion magnetic resonance imaging tractography parcellation methods have been successful in defining major cerebellar fibre tracts, while relying solely on fibre tract structure. However, each fibre tract may relay information related to multiple cognitive and motor functions of the cerebellum. Hence, it may be beneficial for parcellation to consider the potential importance of the fibre tracts for individual motor and cognitive functional performance measures. In this work, we propose a multimodal data-driven method for cerebellar pathway parcellation, which incorporates both measures of microstructure and connectivity, and measures of individual functional performance. Our method involves first training a multitask deep network to predict various cognitive and motor measures from a set of fibre tract structural features. The importance of each structural feature for predicting each functional measure is then computed, resulting in a set of structure-function saliency values that are clustered to parcellate cerebellar pathways. We refer to our method as Deep Multimodal Saliency Parcellation (DeepMSP), as it computes the saliency of structural measures for predicting cognitive and motor functional performance, with these saliencies being applied to the task of parcellation. Applying DeepMSP to a large-scale dataset from the Human Connectome Project Young Adult study (n = 1065), we found that it was feasible to identify multiple cerebellar pathway parcels with unique structure-function saliency patterns that were stable across training folds. We thoroughly experimented with all stages of the DeepMSP pipeline, including network selection, structure-function saliency representation, clustering algorithm, and cluster count. We found that a 1D convolutional neural network architecture and a transformer network architecture both performed comparably for the multitask prediction of endurance, strength, reading decoding, and vocabulary comprehension, with both architectures outperforming a fully connected network architecture. Quantitative experiments demonstrated that a proposed low-dimensional saliency representation with an explicit measure of motor versus cognitive category bias achieved the best parcellation results, while a parcel count of four was most successful according to standard cluster quality metrics. Our results suggested that motor and cognitive saliencies are distributed across the cerebellar white matter pathways. Inspection of the final k = 4 parcellation revealed that the highest-saliency parcel was most salient for the prediction of both motor and cognitive performance scores and included parts of the middle and superior cerebellar peduncles. Our proposed saliency-based parcellation framework, DeepMSP, enables multimodal, data-driven tractography parcellation. Through utilising both structural features and functional performance measures, this parcellation strategy may have the potential to enhance the study of structure-function relationships of the cerebellar pathways.
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Affiliation(s)
- Ari Tchetchenian
- Biomedical Image Computing Group, School of Computer Science and EngineeringUniversity of New South Wales (UNSW)SydneyNew South WalesAustralia
| | - Leo Zekelman
- Department of Radiology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
- Harvard UniversityCambridgeMassachusettsUSA
| | - Yuqian Chen
- Department of Radiology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Jarrett Rushmore
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of RadiologyMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of Anatomy and NeurobiologyBoston University School of MedicineBostonMassachusettsUSA
| | - Fan Zhang
- School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina
| | | | - Nikos Makris
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of RadiologyMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
- Department of Psychiatry, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Yogesh Rathi
- Department of Radiology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
- Department of Psychiatry, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
| | - Erik Meijering
- Biomedical Image Computing Group, School of Computer Science and EngineeringUniversity of New South Wales (UNSW)SydneyNew South WalesAustralia
| | - Yang Song
- Biomedical Image Computing Group, School of Computer Science and EngineeringUniversity of New South Wales (UNSW)SydneyNew South WalesAustralia
| | - Lauren J. O'Donnell
- Department of Radiology, Brigham and Women's HospitalHarvard Medical SchoolBostonMassachusettsUSA
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Costa RG, Conceição A, Matos CA, Nóbrega C. The polyglutamine protein ATXN2: from its molecular functions to its involvement in disease. Cell Death Dis 2024; 15:415. [PMID: 38877004 PMCID: PMC11178924 DOI: 10.1038/s41419-024-06812-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 06/16/2024]
Abstract
A CAG repeat sequence in the ATXN2 gene encodes a polyglutamine (polyQ) tract within the ataxin-2 (ATXN2) protein, showcasing a complex landscape of functions that have been progressively unveiled over recent decades. Despite significant progresses in the field, a comprehensive overview of the mechanisms governed by ATXN2 remains elusive. This multifaceted protein emerges as a key player in RNA metabolism, stress granules dynamics, endocytosis, calcium signaling, and the regulation of the circadian rhythm. The CAG overexpansion within the ATXN2 gene produces a protein with an extended poly(Q) tract, inducing consequential alterations in conformational dynamics which confer a toxic gain and/or partial loss of function. Although overexpanded ATXN2 is predominantly linked to spinocerebellar ataxia type 2 (SCA2), intermediate expansions are also implicated in amyotrophic lateral sclerosis (ALS) and parkinsonism. While the molecular intricacies await full elucidation, SCA2 presents ATXN2-associated pathological features, encompassing autophagy impairment, RNA-mediated toxicity, heightened oxidative stress, and disruption of calcium homeostasis. Presently, SCA2 remains incurable, with patients reliant on symptomatic and supportive treatments. In the pursuit of therapeutic solutions, various studies have explored avenues ranging from pharmacological drugs to advanced therapies, including cell or gene-based approaches. These endeavours aim to address the root causes or counteract distinct pathological features of SCA2. This review is intended to provide an updated compendium of ATXN2 functions, delineate the associated pathological mechanisms, and present current perspectives on the development of innovative therapeutic strategies.
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Affiliation(s)
- Rafael G Costa
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal.
- PhD program in Biomedical Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal.
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal.
| | - André Conceição
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal
- PhD program in Biomedical Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), Coimbra, Portugal
- Champalimaud Research Program, Champalimaud Center for the Unknown, Lisbon, Portugal
| | - Carlos A Matos
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal
| | - Clévio Nóbrega
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal.
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve (UAlg), Faro, Portugal.
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3
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Al-Arab N, Hannoun S. White matter integrity assessment in spinocerebellar ataxia type 2 (SCA2) patients. Clin Radiol 2024; 79:67-72. [PMID: 37953094 DOI: 10.1016/j.crad.2023.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 10/10/2023] [Accepted: 10/15/2023] [Indexed: 11/14/2023]
Abstract
AIM To assess the burden of white matter (WM) damage in the cerebrum and cerebellum of spinocerebellar ataxia type 2 (SCA2) patients in an attempt to identify key regions affected by the neurodegenerative processes using diffusion tensor imaging (DTI). MATERIALS AND METHODS Nine SCA2 patients and 16 age-matched healthy controls were examined twice (SCA2 patients 3.6 ± 0.7 years and controls 3.3 ± 1.0 years apart) on the same 1.5 T scanner by acquiring T1-weighted and diffusion-weighted (b-value = 1,000 s/mm2) images. Using tract-based spatial statistics, DTI analysis on fractional anisotropy (FA), mean diffusivity (MD), axial (AD)/radial (RD) diffusivity was performed. RESULTS At baseline magnetic resonance imaging (MRI), FA was significantly decreased in SCA2 patients in the corticospinal tracts, inferior and superior cerebellar peduncles, middle cerebellar peduncles, cerebral peduncles, right superior and posterior corona radiata. RD was only significantly increased in SCA2 patients in the middle cerebellar peduncles. No significant AD and MD changes were observed. Tract-based spatial statistics (TBSS) analysis between SCA2 patients at baseline and at follow-up showed no significant changes in any of the DTI metrics. CONCLUSIONS DTI is a sensitive tool for following the progression of WM neurodegeneration and severity assessment in patients with SCA2. These findings add to a better understanding of the neurological underpinnings of the symptoms experienced by SCA2 patients.
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Affiliation(s)
- N Al-Arab
- Department of Diagnostic Radiology, American University of Beirut Medical Center, Beirut, Lebanon
| | - S Hannoun
- Medical Imaging Sciences Program, Division of Health Professions, Faculty of Public Health, American University of Beirut, Beirut, Lebanon; Abu-Haidar Neuroscience Institute, Faculty of Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
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Stezin A, Bhardwaj S, Khokhar S, Hegde S, Jain S, Bharath RD, Saini J, Pal PK. In vivo microstructural white matter changes in early spinocerebellar ataxia 2. Acta Neurol Scand 2021; 143:326-332. [PMID: 33029780 DOI: 10.1111/ane.13359] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 09/24/2020] [Accepted: 10/05/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVE White matter (WM) integrity of Spinocerebellar ataxia 2 (SCA2) is poorly understood, more so in the early stages of SCA2. In this study, we evaluated the microstructural integrity of the WM tracts with an emphasis on the nature of in vivo pathological involvement in early SCA2. MATERIALS AND METHODS We evaluated the MRI images of 26 genetically proven SCA2 patients with disease duration <5 years and 24 age- and gender-matched healthy controls using tract-based spatial statistics (TBSS) to identify the WM tract changes and their clinico-genetic correlates (age at onset, duration of disease, ataxia severity and CAG repeat length) using standard methodology. RESULTS The mean age at onset and duration of disease were 28.7 ± 8.51 years and 3.5 ± 0.69 months, respectively. The mean CAG repeat length was 42.5 ± 4.6, and the ataxia severity score was 16.1 ± 4.9. Altered DTI scalars signifying degeneration was present in the bilateral anterior thalamic radiation (ATR), corticospinal tract (CST), inferior fronto-occipital fasciculus (IFOF), superior and inferior longitudinal fasciculus (SLF and ILF), uncinate fasciculus (UF), cingulum, corpus callosum (CC), forceps major and forceps minor (corrected p < .05). DTI scalars representing demyelination was seen in the superior cerebellar peduncle (SCP) and cerebellar WM. There was a significant correlation of SARA score with axial diffusivity of the bilateral cingulum, ATR, CST, forceps minor, IFOF, ILF, SLF and SCP on the right side (corrected p < .05). CONCLUSION Extensive WM involvement is present in early SCA2. The DTI scalars indicate degeneration and demyelination and may have clinical implications.
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Affiliation(s)
- Albert Stezin
- Department of Clinical Neurosciences, Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sujas Bhardwaj
- Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sunil Khokhar
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Shantala Hegde
- Department of Clinical Neuropsychology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Sanjeev Jain
- Department of Psychiatry National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Jitender Saini
- Department of Neuroimaging and Interventional Radiology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
| | - Pramod Kumar Pal
- Department of Neurology National Institute of Mental Health & Neurosciences (NIMHANS) Bangalore India
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5
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Nigri A, Sarro L, Mongelli A, Pinardi C, Porcu L, Castaldo A, Ferraro S, Grisoli M, Bruzzone MG, Gellera C, Taroni F, Mariotti C, Nanetti L. Progression of Cerebellar Atrophy in Spinocerebellar Ataxia Type 2 Gene Carriers: A Longitudinal MRI Study in Preclinical and Early Disease Stages. Front Neurol 2020; 11:616419. [PMID: 33384659 PMCID: PMC7770103 DOI: 10.3389/fneur.2020.616419] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
Spinocerebellar ataxias type 2 (SCA2) is an autosomal dominant inherited disease caused by expanded trinucleotide repeats (≥32 CAG) within the coding region of ATXN2 gene. Age of disease onset primarily depends on the length of the expanded region. The majority of subjects carrying the mutation remain free of clinical signs for few decades (“pre-symptomatic” stage), but in proximity of disease onset subtle neurophysiological, cognitive, and structural brain imaging changes may occur. Aims of the present study are to determine the time-window in which early clinical and neurodegenerative MRI changes may be identified, and to evaluate the rate of the disease progression in both preclinical and early disease phases. We performed a 1-year longitudinal study in 42 subjects: 14 SCA2 patients (mean age 39 years, disease duration 7 years, SARA score 9 points), 13 presymptomatic SCA2 subjects (preSCA2, mean age 39 years, expected time to disease onset 16 years), and 15 gene-negative healthy controls (mean age 33 years). All participants underwent genetic test, neurological examination, cognitive tests, and brain MRI. Evaluations were repeated at 1-year interval. Baseline MRI evaluations in SCA2 patients showed significant atrophy in cerebellum, brainstem, basal ganglia and cortex compared to controls, while preSCA2 subjects had isolated volume loss in the pons, and cortical thinning in specific frontal and parietal areas, namely rostral-middle-frontal and precuneus. One-year longitudinal follow-up demonstrated, in SCA2 patients, volume reduction in cerebellum, pons, superior cerebellar peduncles, and midbrain, and only in the cerebellum in preSCA2 subjects. No progression in clinical or cognitive measures was observed in preSCA2 subjects. The rate of volume loss in the cerebellum and subcortical regions greatly differed between patients and preSCA2. In conclusion, our pilot study demonstrated that MRI measures are highly sensitive to identify longitudinal structural changes in SCA2 patients, and in preSCA2 up to a decade before expected disease onset. These findings may contribute in the understanding of early neurodegenerative processes and may be useful in future therapeutical trials.
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Affiliation(s)
- Anna Nigri
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Lidia Sarro
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy.,Ospedale Martini, Turin, Italy
| | - Alessia Mongelli
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Chiara Pinardi
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Luca Porcu
- Laboratory of Methodology for Clinical Research, Oncology Department, Istituto di Ricerche Farmacologiche Mario Negri Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS), Milan, Italy
| | - Anna Castaldo
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Stefania Ferraro
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marina Grisoli
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Maria Grazia Bruzzone
- Department of Neuroradiology, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Cinzia Gellera
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Franco Taroni
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Caterina Mariotti
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
| | - Lorenzo Nanetti
- Department of Medical Genetics and Neurogenetics, Fondazione Istituto di Ricerca e Cura a Carattere Scientifico (IRCCS) Istituto Neurologico Carlo Besta, Milan, Italy
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Wan N, Chen Z, Wan L, Tang B, Jiang H. MR Imaging of SCA3/MJD. Front Neurosci 2020; 14:749. [PMID: 32848545 PMCID: PMC7417615 DOI: 10.3389/fnins.2020.00749] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/25/2020] [Indexed: 12/15/2022] Open
Abstract
Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a progressive autosomal dominantly inherited cerebellar ataxia characterized by the aggregation of polyglutamine-expanded protein within neuronal nuclei in the brain, which can lead to brain damage that precedes the onset of clinical manifestations. Magnetic resonance imaging (MRI) techniques such as morphometric MRI, diffusion tensor imaging (DTI), functional magnetic resonance imaging (fMRI), and magnetic resonance spectroscopy (MRS) have gained increasing attention as non-invasive and quantitative methods for the assessment of structural and functional alterations in clinical SCA3/MJD patients as well as preclinical carriers. Morphometric MRI has demonstrated typical patterns of atrophy or volume loss in the cerebellum and brainstem with extensive lesions in some supratentorial areas. DTI has detected widespread microstructural alterations in brain white matter, which indicate disrupted brain anatomical connectivity. Task-related fMRI has presented unusual brain activation patterns within the cerebellum and some extracerebellar tissue, reflecting the decreased functional connectivity of these brain regions in SCA3/MJD subjects. MRS has revealed abnormal neurochemical profiles, such as the levels or ratios of N-acetyl aspartate, choline, and creatine, in both clinical cases and preclinical cases before the alterations in brain anatomical structure. Moreover, a number of studies have reported correlations of MR imaging alterations with clinical and genetic features. The utility of these MR imaging techniques can help to identify preclinical SCA3/MJD carriers, monitor disease progression, evaluate response to therapeutic interventions, and illustrate the pathophysiological mechanisms underlying the occurrence, development, and prognosis of SCA3/MJD.
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Affiliation(s)
- Na Wan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhao Chen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
| | - Linlin Wan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
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7
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Cerebellar Astrocytes: Much More Than Passive Bystanders In Ataxia Pathophysiology. J Clin Med 2020; 9:jcm9030757. [PMID: 32168822 PMCID: PMC7141261 DOI: 10.3390/jcm9030757] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/06/2020] [Accepted: 03/09/2020] [Indexed: 12/22/2022] Open
Abstract
Ataxia is a neurodegenerative syndrome, which can emerge as a major element of a disease or represent a symptom of more complex multisystemic disorders. It comprises several forms with a highly variegated etiology, mainly united by motor, balance, and speech impairments and, at the tissue level, by cerebellar atrophy and Purkinje cells degeneration. For this reason, the contribution of astrocytes to this disease has been largely overlooked in the past. Nevertheless, in the last few decades, growing evidences are pointing to cerebellar astrocytes as crucial players not only in the progression but also in the onset of distinct forms of ataxia. Although the current knowledge on this topic is very fragmentary and ataxia type-specific, the present review will attempt to provide a comprehensive view of astrocytes’ involvement across the distinct forms of this pathology. Here, it will be highlighted how, through consecutive stage-specific mechanisms, astrocytes can lead to non-cell autonomous neurodegeneration and, consequently, to the behavioral impairments typical of this disease. In light of that, treating astrocytes to heal neurons will be discussed as a potential complementary therapeutic approach for ataxic patients, a crucial point provided the absence of conclusive treatments for this disease.
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8
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Mascalchi M, Vella A. Neuroimaging Biomarkers in SCA2 Gene Carriers. Int J Mol Sci 2020; 21:ijms21031020. [PMID: 32033120 PMCID: PMC7037189 DOI: 10.3390/ijms21031020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 12/12/2022] Open
Abstract
A variety of Magnetic Resonance (MR) and nuclear medicine (NM) techniques have been used in symptomatic and presymptomatic SCA2 gene carriers to explore, in vivo, the physiopathological biomarkers of the neurological dysfunctions characterizing the associated progressive disease that presents with a cerebellar syndrome, or less frequently, with a levodopa-responsive parkinsonian syndrome. Morphometry performed on T1-weighted images and diffusion MR imaging enable structural and microstructural evaluation of the brain in presymptomatic and symptomatic SCA2 gene carriers, in whom they show the typical pattern of olivopontocerebellar atrophy observed at neuropathological examination. Proton MR spectroscopy reveals, in the pons and cerebellum of SCA2 gene carriers, a more pronounced degree of abnormal neurochemical profile compared to other spinocerebellar ataxias with decreased NAA/Cr and Cho/Cr, increased mi/Cr ratios, and decreased NAA and increased mI concentrations. These neurochemical abnormalities are detectable also in presymtomatic gene carriers. Resting state functional MRI (rsfMRI) demonstrates decreased functional connectivity within the cerebellum and of the cerebellum with fronto-parietal cortices and basal ganglia in symptomatic SCA2 subjects. 18F-fluorodeoxyglucose Positron Emission Tomography (PET) shows a symmetric decrease of the glucose uptake in the cerebellar cortex, the dentate nucleus, the brainstem and the parahippocampal cortex. Single photon emission tomography and PET using several radiotracers have revealed almost symmetric nigrostriatal dopaminergic dysfunction irrespective of clinical signs of parkinsonism which are already present in presymtomatic gene carriers. Longitudinal small size studies have proven that morphometry and diffusion MR imaging can track neurodegeneration in SCA2, and hence serve as progression biomarkers. So far, such a capability has not been reported for proton MR spectroscopy, rsfMRI and NM techniques. A search for the best surrogate marker for future clinical trials represents the current challenge for the neuroimaging community.
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Affiliation(s)
- Mario Mascalchi
- Department of Clinical and Experimental Biomedical Sciences, University of Florence, 50121 Florence, Italy
- Correspondence: ; Tel.: +39-329-808-1701
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9
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Banez-Coronel M, Ranum LPW. Repeat-associated non-AUG (RAN) translation: insights from pathology. J Transl Med 2019; 99:929-942. [PMID: 30918326 PMCID: PMC7219275 DOI: 10.1038/s41374-019-0241-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 01/29/2019] [Indexed: 12/14/2022] Open
Abstract
More than 40 different neurological diseases are caused by microsatellite repeat expansions. Since the discovery of repeat-associated non-AUG (RAN) translation by Zu et al. in 2011, nine expansion disorders have been identified as RAN-positive diseases. RAN proteins are translated from different types of nucleotide repeat expansions and can be produced from both sense and antisense transcripts. In some diseases, RAN proteins have been shown to accumulate in affected brain regions. Here we review the pathological and molecular aspects associated with RAN protein accumulation for each particular disorder, the correlation between disease pathology and the available in vivo models and the common aspects shared by some of the newly discovered RAN proteins.
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Affiliation(s)
- Monica Banez-Coronel
- Center for NeuroGenetics, University of Florida, Gainesville, FL, 32610, USA
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, 32610, USA
| | - Laura P W Ranum
- Center for NeuroGenetics, University of Florida, Gainesville, FL, 32610, USA.
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, 32610, USA.
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
- McKnight Brain Institute, University of Florida, Gainesville, FL, 32610, USA.
- Genetics Institute, University of Florida, Gainesville, FL, 32610, USA.
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10
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Coarelli G, Brice A, Durr A. Recent advances in understanding dominant spinocerebellar ataxias from clinical and genetic points of view. F1000Res 2018; 7. [PMID: 30473770 PMCID: PMC6234732 DOI: 10.12688/f1000research.15788.1] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/02/2018] [Indexed: 12/12/2022] Open
Abstract
Abstract Spinocerebellar ataxias (SCAs) are rare types of cerebellar ataxia with a dominant mode of inheritance. To date, 47 SCA subtypes have been identified, and the number of genes implicated in SCAs is continually increasing. Polyglutamine (polyQ) expansion diseases (
ATXN1/SCA1,
ATXN2/SCA2,
ATXN3/SCA3,
CACNA1A/SCA6,
ATXN7/SCA7,
TBP/SCA17, and
ATN1/DRPLA) are the most common group of SCAs. No preventive or curative treatments are currently available, but various therapeutic approaches, including RNA-targeting treatments, such as antisense oligonucleotides (ASOs), are being developed. Clinical trials of ASOs in SCA patients are already planned. There is, therefore, a need to identify valid outcome measures for such studies. In this review, we describe recent advances towards identifying appropriate biomarkers, which are essential for monitoring disease progression and treatment efficacy. Neuroimaging biomarkers are the most powerful markers identified to date, making it possible to reduce sample sizes for clinical trials. Changes on brain MRI are already evident at the premanifest stage in SCA1 and SCA2 carriers and are correlated with CAG repeat size. Other potential biomarkers have also been developed, based on neurological examination, oculomotor study, cognitive assessment, and blood and cerebrospinal fluid analysis. Longitudinal studies based on multimodal approaches are required to establish the relationships between parameters and to validate the biomarkers identified.
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Affiliation(s)
- Giulia Coarelli
- Assistance Publique-Hôpitaux de Paris (AP-HP), Department of Neurology, Avicenne Hospital, Paris 13 University, Bobigny, 93000, France.,Institut du Cerveau et de la Moelle épinière, ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne University, Paris, 75013, France
| | - Alexis Brice
- Institut du Cerveau et de la Moelle épinière, ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne University, Paris, 75013, France.,Assistance Publique-Hôpitaux de Paris (AP-HP), Genetic department, Pitié-Salpêtrière University Hospital, Paris, 75013, France
| | - Alexandra Durr
- Institut du Cerveau et de la Moelle épinière, ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne University, Paris, 75013, France.,Assistance Publique-Hôpitaux de Paris (AP-HP), Genetic department, Pitié-Salpêtrière University Hospital, Paris, 75013, France
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11
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Lupo M, Olivito G, Iacobacci C, Clausi S, Romano S, Masciullo M, Molinari M, Cercignani M, Bozzali M, Leggio M. The cerebellar topography of attention sub-components in spinocerebellar ataxia type 2. Cortex 2018; 108:35-49. [PMID: 30121445 DOI: 10.1016/j.cortex.2018.07.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 06/07/2018] [Accepted: 07/16/2018] [Indexed: 01/10/2023]
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease characterized by a progressive cerebellar syndrome and multiple-domain cognitive impairments. The cerebellum is known to contribute to distinct functional networks related to higher-level functions. The aims of the present study were to investigate the different sub-components of attention and to analyse possible correlations between attention deficits and specific cerebellar regions in SCA2 patients. To this purpose, 11 SCA2 patients underwent an exhaustive attention battery that evaluated several attention sub-components. The SCA2 group performed below the normal range in tasks assessing selective attention, divided attention, and sustained attention, obtaining negative Z-scores. These results were confirmed by non-parametric Mann-Whitney U tests that showed significant differences between SCA2 and control subjects in the same sub-components of the attention battery, allowing us to speculate on cerebellar involvement when a high cognitive demand is required (i.e., multisensory integration, sequencing, prediction of events, and inhibition of inappropriate response behaviours). The voxel-based morphometry analysis showed a pattern of significantly reduced grey matter volume in specific cerebellar lobules. In particular, the SCA2 patients showed significant grey matter loss in bilateral regions of the anterior cerebellar hemisphere (IV) and in the posterior lobe (VI-IX) and posterior vermis (VI-IX). Statistical analysis found significant correlations between grey matter reductions in the VIIb/VIIIa cerebellar lobules and impairments in Sustained and Divided Attention tasks and between grey matter reduction in the vermal VI lobule and impairment in the Go/NoGo task. For the first time, the study demonstrated the involvement of specific cerebellar lobules in different sub-components of the attention domain, giving further support to the inclusion of the cerebellum within the attention network.
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Affiliation(s)
- Michela Lupo
- Ataxia Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy.
| | - Giusy Olivito
- Ataxia Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; Neuroimaging Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Claudia Iacobacci
- Ataxia Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; PhD Program in Behavioral Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Silvia Clausi
- Ataxia Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Psychology, Sapienza University of Rome, Rome, Italy
| | - Silvia Romano
- Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), "Sapienza" University of Rome, Sant'Andrea Hospital, Rome, Italy
| | | | - Marco Molinari
- Neurorehabilitation 1 and Spinal Center, Robotic Neurorehabilitation Lab, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Mara Cercignani
- Neuroimaging Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; Clinical Imaging Science Center, Brighton and Sussex Medical School, Brighton, UK
| | - Marco Bozzali
- Neuroimaging Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; Clinical Imaging Science Center, Brighton and Sussex Medical School, Brighton, UK
| | - Maria Leggio
- Ataxia Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy; Department of Psychology, Sapienza University of Rome, Rome, Italy
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12
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Mascalchi M, Marzi C, Giannelli M, Ciulli S, Bianchi A, Ginestroni A, Tessa C, Nicolai E, Aiello M, Salvatore E, Soricelli A, Diciotti S. Histogram analysis of DTI-derived indices reveals pontocerebellar degeneration and its progression in SCA2. PLoS One 2018; 13:e0200258. [PMID: 30001379 PMCID: PMC6042729 DOI: 10.1371/journal.pone.0200258] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 06/24/2018] [Indexed: 12/16/2022] Open
Abstract
PURPOSE To assess the potential of histogram metrics of diffusion-tensor imaging (DTI)-derived indices in revealing neurodegeneration and its progression in spinocerebellar ataxia type 2 (SCA2). MATERIALS AND METHODS Nine SCA2 patients and 16 age-matched healthy controls, were examined twice (SCA2 patients 3.6±0.7 years and controls 3.3±1.0 years apart) on the same 1.5T scanner by acquiring T1-weighted and diffusion-weighted (b-value = 1000 s/mm2) images. Cerebrum and brainstem-cerebellum regions were segmented using FreeSurfer suite. Histogram analysis of DTI-derived indices, including mean diffusivity (MD), fractional anisotropy (FA), axial (AD) / radial (RD) diffusivity and mode of anisotropy (MO), was performed. RESULTS At baseline, significant differences between SCA2 patients and controls were confined to brainstem-cerebellum. Median values of MD/AD/RD and FA/MO were significantly (p<0.001) higher and lower, respectively, in SCA2 patients (1.11/1.30/1.03×10(-3) mm2/s and 0.14/0.19) than in controls (0.80/1.00/0.70×10(-3) mm2/s and 0.20/0.41). Also, peak location values of MD/AD/RD and FA were significantly (p<0.001) higher and lower, respectively, in SCA2 patients (0.91/1.11/0.81×10(-3) mm2/s and 0.12) than in controls (0.71/0.91/0.63×10(-3) mm2/s and 0.18). Peak height values of FA and MD/AD/RD/MO were significantly (p<0.001) higher and lower, respectively, in SCA2 patients (0.20 and 0.07/0.06/0.07×10(-3) mm2/s/year /0.07) than in controls (0.15 and 0.14/0.11/0.12/×10(-3) mm2/s/year /0.09). The rate of change of MD median values was significantly (p<0.001) higher (i.e., increased) in SCA2 patients (0.010×10(-3) mm2/s/year) than in controls (-0.003×10(-3) mm2/s/year) in the brainstem-cerebellum, whereas no significant difference was found for other indices and in the cerebrum. CONCLUSION Histogram analysis of DTI-derived indices is a relatively straightforward approach which reveals microstructural changes associated with pontocerebellar degeneration in SCA2 and the median value of MD is capable to track its progression.
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Affiliation(s)
- Mario Mascalchi
- “Mario Serio” Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
- * E-mail:
| | - Chiara Marzi
- Department of Electrical, Electronic, and Information Engineering “Guglielmo Marconi”, University of Bologna, Cesena, Italy
| | - Marco Giannelli
- Unit of Medical Physics, Pisa University Hospital “Azienda Ospedaliero-Universitaria Pisana”, Pisa, Italy
| | - Stefano Ciulli
- “Mario Serio” Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Andrea Bianchi
- “Mario Serio” Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Andrea Ginestroni
- Neuroradiology Unit, Azienda Ospedaliero Universitaria Careggi, Florence, Italy
| | - Carlo Tessa
- Department of Radiology and Nuclear Medicine, Versilia Hospital, AUSL 12 Viareggio, Lido di Camaiore (Lu), Italy
| | | | | | - Elena Salvatore
- Department of Neurological Sciences, University of Naples Federico II, Naples, Italy
| | | | - Stefano Diciotti
- Department of Electrical, Electronic, and Information Engineering “Guglielmo Marconi”, University of Bologna, Cesena, Italy
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13
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Zhu M, Xu Y, Wang H, Shen Z, Xie Z, Chen F, Gao Y, Chen X, Zhang Y, Wu Q, Li X, Yu J, Luo H, Wang K. Heroin Abuse Results in Shifted RNA Expression to Neurodegenerative Diseases and Attenuation of TNFα Signaling Pathway. Sci Rep 2018; 8:9231. [PMID: 29915338 PMCID: PMC6006288 DOI: 10.1038/s41598-018-27419-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/31/2018] [Indexed: 12/18/2022] Open
Abstract
Repeated administration of heroin results in the induction of physical dependence, which is characterized as a behavioral state of compulsive drug seeking and a high rate of relapse even after periods of abstinence. However, few studies have been dedicated to characterization of the long-term alterations in heroin-dependent patients (HDPs). Herein, we examined the peripheral blood from 810 HDPs versus 500 healthy controls (HCs) according to the inclusion criteria. Compared with the control group, significant decreases of albumin, triglyceride, and total cholesterol levels were identified in HDPs (P < 0.001) versus HCs coupled with an insignificant decrease in BMI. Meanwhile, RNA-sequencing analyses were performed on blood of 16 long-term HDPs and 25 HCs. The results showed that the TNFα signaling pathway and hematopoiesis related genes were inhibited in HDPs. We further compared the transcriptome data to those of SCA2 and posttraumatic stress disorder patients, identified neurodegenerative diseases related genes were commonly up-regulated in coupled with biological processes "vesicle transport", "mitochondria" and "splicing". Genes in the categories of "protein ubiquitination" were down-regulated indicating potential biochemical alterations shared by all three comparative to their controls. In summary, this is a leading study performing a series of through investigations and using delicate approaches. Results from this study would benefit the study of drug addiction overall and link long-term heroin abuse to neurodegenerative diseases.
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Affiliation(s)
- Mei Zhu
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Yu Xu
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Huawei Wang
- Department of Gastrointestinal surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Zongwen Shen
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
- Kunming Engineering Technology Center of Diagnosis and Treatment of Digestive Diseases, Kunming, 650032, Yunnan, China
| | - Zhenrong Xie
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
- Department of reproduction and genetics, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Fengrong Chen
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
- Department of reproduction and genetics, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Yunhong Gao
- Yunnan Drug Enforcement Commission Office, Kunming, 650032, Yunnan, China
- Yunnan Drug Enforcement Administration, Kunming, 650032, Yunnan, China
| | - Xin Chen
- Yunnan Drug Enforcement Commission Office, Kunming, 650032, Yunnan, China
- Yunnan Drug Enforcement Administration, Kunming, 650032, Yunnan, China
| | - Ying Zhang
- Yunnan Drug Enforcement Commission Office, Kunming, 650032, Yunnan, China
- Yunnan Drug Enforcement Administration, Kunming, 650032, Yunnan, China
| | - Qiang Wu
- Yunnan Drug Enforcement Commission Office, Kunming, 650032, Yunnan, China
- Yunnan Drug Enforcement Administration, Kunming, 650032, Yunnan, China
| | - Xuejun Li
- Yunnan Drug Enforcement Commission Office, Kunming, 650032, Yunnan, China
- Yunnan Drug Enforcement Administration, Kunming, 650032, Yunnan, China
| | - Juehua Yu
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China
| | - Huayou Luo
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China.
| | - Kunhua Wang
- Yunnan Institute of Digestive Disease, the First Affiliated Hospital of Kunming Medical University, Kunming, 650032, Yunnan, China.
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14
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Adanyeguh IM, Perlbarg V, Henry PG, Rinaldi D, Petit E, Valabregue R, Brice A, Durr A, Mochel F. Autosomal dominant cerebellar ataxias: Imaging biomarkers with high effect sizes. NEUROIMAGE-CLINICAL 2018; 19:858-867. [PMID: 29922574 PMCID: PMC6005808 DOI: 10.1016/j.nicl.2018.06.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/19/2018] [Accepted: 06/07/2018] [Indexed: 12/13/2022]
Abstract
Objective As gene-based therapies may soon arise for patients with spinocerebellar ataxia (SCA), there is a critical need to identify biomarkers of disease progression with effect sizes greater than clinical scores, enabling trials with smaller sample sizes. Methods We enrolled a unique cohort of patients with SCA1 (n = 15), SCA2 (n = 12), SCA3 (n = 20) and SCA7 (n = 10) and 24 healthy controls of similar age, sex and body mass index. We collected longitudinal clinical and imaging data at baseline and follow-up (mean interval of 24 months). We performed both manual and automated volumetric analyses. Diffusion tensor imaging (DTI) and a novel tractography method, called fixel-based analysis (FBA), were assessed at follow-up. Effect sizes were calculated for clinical scores and imaging parameters. Results Clinical scores worsened as atrophy increased over time (p < 0.05). However, atrophy of cerebellum and pons showed very large effect sizes (>1.2) compared to clinical scores (<0.8). FBA, applied for the first time to SCA, was sensitive to microstructural cross-sectional differences that were not captured by conventional DTI metrics, especially in the less studied SCA7 group. FBA also showed larger effect sizes than DTI metrics. Conclusion This study showed that volumetry outperformed clinical scores to measure disease progression in SCA1, SCA2, SCA3 and SCA7. Therefore, we advocate the use of volumetric biomarkers in therapeutic trials of autosomal dominant ataxias. In addition, FBA showed larger effect size than DTI to detect cross-sectional microstructural alterations in patients relative to controls. Biomarkers are needed to test upcoming therapies for spinocerebellar ataxia. As spinocerebellar ataxias are rare, biomarkers with high effect sizes are needed. We identified imaging biomarkers with higher effect sizes than clinical scores.
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Key Words
- Apparent fiber density
- CCFS, composite cerebellar functional severity score
- CFE, connectivity-based fixel enhancement
- CSD, constrained spherical deconvolution
- CST, corticospinal tract
- DTI, diffusion tensor imaging
- Diffusion imaging.
- FA, fractional anisotropy
- FBA, fixel-based analysis
- FC, fiber cross-section
- FD, fiber density
- FDC, fiber density and cross-section
- FOD, fiber orientation distribution
- FOV, Field of view
- Fixel analysis
- GRAPPA, generalized autocalibrating partial parallel acquisition
- Imaging biomarkers
- MPRAGE, magnetization-prepared rapid gradient-echo
- MRI, magnetic resonance imaging
- RD, radial diffusivity
- SARA, scale for the assessment and rating of ataxia
- SCA, spinocerebellar ataxias
- SNR, signal-to-noise ratio
- Spinocerebellar ataxia
- TBSS, tract-based spatial statistics
- TE, echo time
- TR, repetition time
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Affiliation(s)
- Isaac M Adanyeguh
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Vincent Perlbarg
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Bioinformatics and Biostatistics Core Facililty, iCONICS, Institut du Ceveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Pierre-Gilles Henry
- Center for Magnetic Resonance Research (CMRR), University of Minnesota, Minneapolis, MN, United States
| | - Daisy Rinaldi
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Elodie Petit
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Romain Valabregue
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; Center for NeuroImaging Research (CENIR), Institut du Cerveau et de la Moelle épinière, 75013 Paris, France
| | - Alexis Brice
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - Alexandra Durr
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; AP-HP, Pitié-Salpêtrière University Hospital, Department of Genetics, Paris, France
| | - Fanny Mochel
- INSERM U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France; AP-HP, Pitié-Salpêtrière University Hospital, Department of Genetics, Paris, France; University Pierre and Marie Curie, Neurometabolic Research Group, Paris, France.
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15
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Reetz K, Rodríguez-Labrada R, Dogan I, Mirzazade S, Romanzetti S, Schulz JB, Cruz-Rivas EM, Alvarez-Cuesta JA, Aguilera Rodríguez R, Gonzalez Zaldivar Y, Auburger G, Velázquez-Pérez L. Brain atrophy measures in preclinical and manifest spinocerebellar ataxia type 2. Ann Clin Transl Neurol 2018; 5:128-137. [PMID: 29468174 PMCID: PMC5817824 DOI: 10.1002/acn3.504] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/06/2017] [Accepted: 10/21/2017] [Indexed: 01/11/2023] Open
Abstract
Objective Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominantly inherited neurodegenerative disease mainly affecting the cerebellum and brainstem. In this Cuban-German research collaboration, we aimed to characterize atrophy patterns and associations with clinical measures in preclinical and manifest SCA2. Methods In this study, 16 nonmanifest SCA2 mutation carriers, 26 manifest patients with SCA2, and 18 healthy control subjects underwent magnetic resonance imaging, as well as genetic and clinical characterization including assessment of ataxia (Scale for the Assessment and Rating of Ataxia) and saccade velocity in Cuba were enrolled. Semiautomated quantitative volumetry of the cerebellum and brainstem, subdivided into the medulla oblongata, the pontine brainstem, and mesencephalon was performed. Additionally, the anteroposterior diameter of the pontine brainstem was measured. Results Analysis of volumetric data revealed degeneration of the cerebellum and brainstem, in particular of pontine volumes and the anteroposterior diameter of the pons, in both manifest SCA2 patients and individuals at risk for SCA2 compared to controls. Comparing patients with nonataxic preclinical SCA2 mutation carriers, we found more pronounced reductions of the pontine brainstem and cerebellum in manifest SCA2. Volumetric data further showed associations with CAG repeat length and predicted age of onset in preclinical SCA2 individuals, and by trend with ataxia signs in patients. Although saccade velocity was associated with reduction in the pontine brainstem in preclinical and manifest SCA2, reduced ability to suppress interfering stimuli measured by the Stroop task was related to cerebellar volume loss in patients. Interpretation Preclinical SCA2 mutation carriers exhibit brain abnormalities, which could be targeted as surrogate parameters for disease progression and in future preventive trials.
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Affiliation(s)
- Kathrin Reetz
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Roberto Rodríguez-Labrada
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Imis Dogan
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Shahram Mirzazade
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Sandro Romanzetti
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Jörg B Schulz
- Department of Neurology RWTH Aachen University Pauwelsstr. 3052074 Aachen Germany.,JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging Forschungszentrum Jülich GmbH and RWTH Aachen University 52074 Aachen Germany
| | - Edilia M Cruz-Rivas
- Department of Imaging Clinical-Surgical Hospital "Lucía Iñiguez". Avenue "Celia Sanchez 1 Holguín Cuba
| | - Jose A Alvarez-Cuesta
- Department of Imaging Clinical-Surgical Hospital "Lucía Iñiguez". Avenue "Celia Sanchez 1 Holguín Cuba
| | - Raul Aguilera Rodríguez
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Yanetza Gonzalez Zaldivar
- Department Molecular Genetics Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
| | - Georg Auburger
- Experimental Neurology Goethe University Medical School 60590 Frankfurt/Main Germany
| | - Luis Velázquez-Pérez
- Department Clinical Neurophysiology Centre for the Research and Rehabilitation of Hereditary Ataxias Calle Libertad 26 Holguín 80100 Cuba
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17
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Wu X, Liao X, Zhan Y, Cheng C, Shen W, Huang M, Zhou Z, Wang Z, Qiu Z, Xing W, Liao W, Tang B, Shen L. Microstructural Alterations in Asymptomatic and Symptomatic Patients with Spinocerebellar Ataxia Type 3: A Tract-Based Spatial Statistics Study. Front Neurol 2017; 8:714. [PMID: 29312133 PMCID: PMC5744430 DOI: 10.3389/fneur.2017.00714] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 12/11/2017] [Indexed: 12/18/2022] Open
Abstract
Objective Spinocerebellar ataxia type 3 (SCA3) is the most commonly occurring type of autosomal dominant spinocerebellar ataxia. The present study aims to investigate progressive changes in white matter (WM) fiber in asymptomatic and symptomatic patients with SCA3. Methods A total of 62 participants were included in this study. Among them, 16 were asymptomatic mutation carriers (pre-SCA3), 22 were SCA3 patients with clinical symptoms, and 24 were normal controls (NC). Group comparison of tract-based spatial statistics was performed to identify microstructural abnormalities at different SCA3 disease stages. Results Decreased fractional anisotropy (FA) and increased mean diffusivity (MD) were found in the left inferior cerebellar peduncle and superior cerebellar peduncle (SCP) in the pre-SCA3 group compared with NC. The symptomatic SCA3 group showed brain-wide WM tracts impairment in both supratentorial and infratentorial networks, and the mean FA value of the WM skeleton showed a significantly negative correlation with the International Cooperative Ataxia Rating Scale (ICARS) scores. Specifically, FA of the bilateral posterior limb of the internal capsule negatively correlated with SCA3 disease duration. We also found that FA values in the right medial lemniscus and SCP negatively correlated with ICARS scores, whereas FA in the right posterior thalamic radiation positively correlated with Montreal Cognitive Assessment scores. In addition, MD in the middle cerebellar peduncle, left anterior limb of internal capsule, external capsule, and superior corona radiate positively correlated with ICARS scores in SCA3 patients. Conclusion WM microstructural changes are present even in the asymptomatic stages of SCA3. In individuals in which the disease has progressed to the symptomatic stage, the integrity of WM fibers across the whole brain is affected. Furthermore, abnormalities in WM tracts are closely related to SCA3 disease severity, including movement disorder and cognitive dysfunction. These findings can deepen our understanding of the neural basis of SCA3 dysfunction.
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Affiliation(s)
- Xinwei Wu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Xinxin Liao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Yafeng Zhan
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Cheng Cheng
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Wei Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Mufang Huang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhifan Zhou
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Zheng Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Zilong Qiu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Wu Xing
- Department of Radiology, Xiangya Hospital, Central South University, Changsha, China
| | - Weihua Liao
- Department of Radiology, Xiangya Hospital, Central South University, Changsha, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China.,State Key Laboratory of Medical Genetics, Changsha, China.,National Clinical Research Center for Geriatric Disease, Changsha, China.,Parkinson's Disease Center of Beijing Institute for Brain Disorders, Beijing, China.,Collaboration Innovation Center for Brain Science, Shanghai, China.,Collaboration Innovation Center for Genetics and Development, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China.,State Key Laboratory of Medical Genetics, Changsha, China.,National Clinical Research Center for Geriatric Disease, Changsha, China
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18
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Microstructural MRI Basis of the Cognitive Functions in Patients with Spinocerebellar Ataxia Type 2. Neuroscience 2017; 366:44-53. [DOI: 10.1016/j.neuroscience.2017.10.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 09/25/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022]
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19
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Velázquez-Pérez LC, Rodríguez-Labrada R, Fernandez-Ruiz J. Spinocerebellar Ataxia Type 2: Clinicogenetic Aspects, Mechanistic Insights, and Management Approaches. Front Neurol 2017; 8:472. [PMID: 28955296 PMCID: PMC5601978 DOI: 10.3389/fneur.2017.00472] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 08/25/2017] [Indexed: 12/14/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant cerebellar ataxia that occurs as a consequence of abnormal CAG expansions in the ATXN2 gene. Progressive clinical features result from the neurodegeneration of cerebellum and extra-cerebellar structures including the pons, the basal ganglia, and the cerebral cortex. Clinical, electrophysiological, and imaging approaches have been used to characterize the natural history of the disease, allowing its classification into four distinct stages, with special emphasis on the prodromal stage, which is characterized by a plethora of motor and non-motor features. Neuropathological investigations of brain tissue from SCA2 patients reveal a widespread involvement of multiple brain systems, mainly cerebellar and brainstem systems. Recent findings linking ataxin-2 intermediate expansions to other neurodegenerative diseases such as amyotrophic lateral sclerosis have provided insights into the ataxin-2-related toxicity mechanism in neurodegenerative diseases and have raised new ethical challenges to molecular predictive diagnosis of SCA2. No effective neuroprotective therapies are currently available for SCA2 patients, but some therapeutic options such as neurorehabilitation and some emerging neuroprotective drugs have shown palliative benefits.
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Affiliation(s)
- Luis C Velázquez-Pérez
- Centre for the Research and Rehabilitation of Hereditary Ataxias, Holguín, Cuba.,Medical University of Holguín "Mariana Grajales", Holguín, Cuba
| | - Roberto Rodríguez-Labrada
- Centre for the Research and Rehabilitation of Hereditary Ataxias, Holguín, Cuba.,Physical Culture School, University of Holguin "Oscar Lucero", Holguín, Cuba
| | - Juan Fernandez-Ruiz
- Department of Physiology, Medicine School, UNAM, Cuernavaca, Mexico.,Psychology School, Universidad Veracruzana, Xalapa, Mexico
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20
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Olivito G, Cercignani M, Lupo M, Iacobacci C, Clausi S, Romano S, Masciullo M, Molinari M, Bozzali M, Leggio M. Neural substrates of motor and cognitive dysfunctions in SCA2 patients: A network based statistics analysis. NEUROIMAGE-CLINICAL 2017; 14:719-725. [PMID: 28393013 PMCID: PMC5377430 DOI: 10.1016/j.nicl.2017.03.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/07/2017] [Accepted: 03/24/2017] [Indexed: 01/04/2023]
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease characterized by a progressive cerebellar syndrome, which can be isolated or associated with extracerebellar signs. It has been shown that patients affected by SCA2 present also cognitive impairments and psychiatric symptoms. The cerebellum is known to modulate cortical activity and to contribute to distinct functional networks related to higher-level functions beyond motor control. It is therefore conceivable that one or more networks, rather than isolated regions, may be dysfunctional in cerebellar degenerative diseases and that an abnormal connectivity within specific cerebello-cortical regions might explain the widespread deficits typically observed in patients. In the present study, the network-based statistics (NBS) approach was used to assess differences in functional connectivity between specific cerebellar and cerebral “nodes” in SCA2 patients. Altered inter-nodal connectivity was found between more posterior regions in the cerebellum and regions in the cerebral cortex clearly related to cognition and emotion. Furthermore, more anterior cerebellar lobules showed altered inter-nodal connectivity with motor and somatosensory cerebral regions. The present data suggest that in SCA2 a cerebellar dysfunction affects long-distance cerebral regions and that the clinical symptoms may be specifically related with connectivity changes between motor and non-motor cerebello-cortical nodes. A cerebellar dysfunction affects long-distance cerebral regions in SCA2 patients. Connectivity changes affect sensorimotor and cognitive cerebello-cortical nodes. Cerebellar symptoms may be related to altered cerebello-cerebral connectivity.
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Affiliation(s)
- G Olivito
- Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy
| | - M Cercignani
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Clinical Imaging Science Center, Brighton and Sussex Medical School, Brighton, UK
| | - M Lupo
- Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy
| | - C Iacobacci
- Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Department of Psychology, Faculty of Medicine and Psychology, "Sapienza" University of Rome, Rome, Italy
| | - S Clausi
- Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Department of Psychology, Faculty of Medicine and Psychology, "Sapienza" University of Rome, Rome, Italy
| | - S Romano
- Department of Neurosciences, Mental Health and Sensory Organs (NESMOS), "Sapienza" University of Rome-Sant'Andrea Hospital, Rome, Italy
| | - M Masciullo
- SPInal REhabilitation Lab, IRCCS Fondazione Santa Lucia,Rome, Italy
| | - M Molinari
- Neurorehabilitation 1 and Spinal Center, Robotic Neurorehabilitation Lab, IRCCS Santa Lucia Foundation, Rome, Italy
| | - M Bozzali
- Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy
| | - M Leggio
- Ataxia Laboratory, IRCCS Santa Lucia Foundation, Rome, Italy; Department of Psychology, Faculty of Medicine and Psychology, "Sapienza" University of Rome, Rome, Italy
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21
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Hernandez-Castillo CR, Vaca-Palomares I, Barrios F, Martinez L, Boll MC, Fernandez-Ruiz J. Ataxia Severity Correlates with White Matter Degeneration in Spinocerebellar Ataxia Type 7. AJNR Am J Neuroradiol 2016; 37:2050-2054. [PMID: 27516240 DOI: 10.3174/ajnr.a4903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 05/26/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE There is a scarcity of information on the effect of white matter degeneration in patients with spinocerebellar ataxia type 7. Therefore, we investigated the WM integrity in a large group of patients with spinocerebellar ataxia type 7 by using Tract-Based Spatial Statistics. MATERIALS AND METHODS Thirty-three patients with a molecular diagnosis of spinocerebellar ataxia type 7 and their age- and sex-matched healthy controls participated in this study. The patients' ataxia severity was evaluated with the Scale for the Assessment and Rating of Ataxia. Voxelwise analyses of diffusion metrics, including fractional anisotropy and mean diffusivity, were performed with Tract-Based Spatial Statistics. The correlation between WM abnormalities and ataxia severity was then calculated. RESULTS Tract-Based Spatial Statistics analysis revealed WM abnormalities in the cerebellum and the cerebellar peduncles, as well as in other major cortical and subcortical pathways. Further analysis between the Scale for the Assessment and Rating of Ataxia score and WM mean diffusivity showed significant associations only in key areas related to motor control and visuospatial processing, including the cerebellar WM, the middle occipital WM, the superior cerebellar peduncle, and bilateral anterior thalamic radiation. No significant associations between fractional anisotropy and the Scale for the Assessment and Rating of Ataxia were found. CONCLUSIONS These results suggest a significant contribution of local cerebellar and cerebellar-midbrain connections to ataxic impairment in spinocerebellar ataxia type 7. The results also suggest an involvement of cortical WM abnormalities including tracts within the occipital and frontal cortices. These findings contribute to a more comprehensive view of the clinical impact of the white matter degeneration in spinocerebellar ataxia type 7.
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Affiliation(s)
- C R Hernandez-Castillo
- From the Consejo Nacional de Ciencia y Tecnologia-Instituto de Neuroetologia (C.R.H.-C.), Universidad Veracruzana, Veracruz, Mexico
| | - I Vaca-Palomares
- Departamento de Fisiologia (I.V.-P., J.F.-R.), Facultad de Medicina
| | - F Barrios
- Instituto de Neurobiologia (F.B.), Universidad Nacional Autonoma de Mexico, Mexico City, Mexico
| | - L Martinez
- Departamento de Neurogenética y Biologıa Molecular (L.M.)
| | - M-C Boll
- Laboratorio de Investigacion Clinica (M.-C.B.), Instituto Nacional de Neurología y Neurocirugía, "Manuel Velasco Suárez," Mexico City, México
| | - J Fernandez-Ruiz
- Departamento de Fisiologia (I.V.-P., J.F.-R.), Facultad de Medicina
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22
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Abstract
OBJECTIVES The aim of this study was to explore the relationship between cognitive and white matter deterioration in a group of participants with spinocerebellar ataxia type 2 (SCA2). METHODS Fourteen genetically confirmed participants with SCA2 and 14 aged-matched controls participated in the study. Diffusion tensor imaging tract-based spatial statistics were performed to analyze structural white matter integrity. Significant group differences in the mean diffusivity were correlated with SCA2 cognitive deficits. RESULTS Our analysis revealed higher mean diffusivity in the SCA2 group in cerebellar white matter, medial lemniscus, and middle cerebellar peduncle, among other regions. Cognitive scores correlated with white matter mean diffusivity in the parahippocampal area, inferior frontal and supramarginal gyri and the stria terminalis. CONCLUSIONS Our findings show significant correlations between white matter microstructural damage in key areas affected in SCA2 and cognitive deficits. These findings result in a more comprehensive understanding of the effect of the neurodegenerative process in people with SCA2.
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