1
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Rezende TJR, Adanyaguh I, Barsottini OGP, Bender B, Cendes F, Coutinho L, Deistung A, Dogan I, Durr A, Fernandez-Ruiz J, Göricke SL, Grisoli M, Hernandez-Castillo CR, Lenglet C, Mariotti C, Martinez ARM, Massuyama BK, Mochel F, Nanetti L, Nigri A, Ono SE, Öz G, Pedroso JL, Reetz K, Synofzik M, Teive H, Thomopoulos SI, Thompson PM, Timmann D, van de Warrenburg BPC, van Gaalen J, França MC, Harding IH. Genotype-specific spinal cord damage in spinocerebellar ataxias: an ENIGMA-Ataxia study. J Neurol Neurosurg Psychiatry 2024; 95:682-690. [PMID: 38383154 DOI: 10.1136/jnnp-2023-332696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 01/17/2024] [Indexed: 02/23/2024]
Abstract
BACKGROUND Spinal cord damage is a feature of many spinocerebellar ataxias (SCAs), but well-powered in vivo studies are lacking and links with disease severity and progression remain unclear. Here we characterise cervical spinal cord morphometric abnormalities in SCA1, SCA2, SCA3 and SCA6 using a large multisite MRI dataset. METHODS Upper spinal cord (vertebrae C1-C4) cross-sectional area (CSA) and eccentricity (flattening) were assessed using MRI data from nine sites within the ENIGMA-Ataxia consortium, including 364 people with ataxic SCA, 56 individuals with preataxic SCA and 394 nonataxic controls. Correlations and subgroup analyses within the SCA cohorts were undertaken based on disease duration and ataxia severity. RESULTS Individuals in the ataxic stage of SCA1, SCA2 and SCA3, relative to non-ataxic controls, had significantly reduced CSA and increased eccentricity at all examined levels. CSA showed large effect sizes (d>2.0) and correlated with ataxia severity (r<-0.43) and disease duration (r<-0.21). Eccentricity correlated only with ataxia severity in SCA2 (r=0.28). No significant spinal cord differences were evident in SCA6. In preataxic individuals, CSA was significantly reduced in SCA2 (d=1.6) and SCA3 (d=1.7), and the SCA2 group also showed increased eccentricity (d=1.1) relative to nonataxic controls. Subgroup analyses confirmed that CSA and eccentricity are abnormal in early disease stages in SCA1, SCA2 and SCA3. CSA declined with disease progression in all, whereas eccentricity progressed only in SCA2. CONCLUSIONS Spinal cord abnormalities are an early and progressive feature of SCA1, SCA2 and SCA3, but not SCA6, which can be captured using quantitative MRI.
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Affiliation(s)
- Thiago Junqueira Ribeiro Rezende
- Department of Neurology, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Isaac Adanyaguh
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | | | - Benjamin Bender
- Department of Diagnostic and Interventional Neuroradiology, University Hospital Tübingen, Tübingen, Germany
| | - Fernando Cendes
- Department of Neurology, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Leo Coutinho
- Graduate program of Internal Medicine, Internal Medicine Department, Hospital de Clínicas, Federal University of Paraná, Curitiba, Brazil
| | - Andreas Deistung
- University Clinic and Outpatient Clinic for Radiology, Department for Radiation Medicine, University Hospital Halle (Saale), University Medicine Halle, Halle (Saale), Germany
| | - Imis Dogan
- Department of Neurology, RWTH Aachen University, Aachen, Germany
- JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Research Center Jülich GmbH, Jülich, Germany
| | - Alexandra Durr
- Sorbonne Université, Paris Brain Institute (ICM), Pitié-Salpêtrière Hospital, AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Paris, France
| | - Juan Fernandez-Ruiz
- Neuropsychology Laboratory, Department of Physiology, Faculty of Medicine, National Autonomous University of Mexico, Mexico City, Mexico
| | - Sophia L Göricke
- Institute of Diagnostic and Interventional Radiology and Neuroradiology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Marina Grisoli
- Department of Neuroradiology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | | | - Christophe Lenglet
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Caterina Mariotti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Alberto R M Martinez
- Department of Neurology, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Breno K Massuyama
- Department of Neurology, Federal University of São Paulo, São Paulo, SP, Brazil
| | - Fanny Mochel
- Assistance Publique-Hôpitaux de Paris, Pitié-Salpêtrière University Hospital, Paris, France
| | - Lorenzo Nanetti
- Unit of Medical Genetics and Neurogenetics, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Anna Nigri
- Department of Neuroradiology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Sergio E Ono
- Clínica DAPI - Diagnóstico Avançado Por Imagem, Curitiba, Brazil
| | - Gülin Öz
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - José Luiz Pedroso
- Department of Neurology, Federal University of São Paulo, São Paulo, SP, Brazil
| | - Kathrin Reetz
- Department of Neurology, RWTH Aachen University, Aachen, Germany
- JARA-BRAIN Institute Molecular Neuroscience and Neuroimaging, Research Center Jülich GmbH, Jülich, Germany
| | - Matthis Synofzik
- Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research, Tübingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany
| | - Helio Teive
- Graduate program of Internal Medicine, Internal Medicine Department, Hospital de Clínicas, Federal University of Paraná, Curitiba, Brazil
- Movement Disorders Unit, Neurology Service, Internal Medicine Department, Hospital de Clínicas, Federal University of Paraná, Curitiba, Brazil
| | - Sophia I Thomopoulos
- Imaging Genetics Center, Mark and Mary Stevens Institute for Neuroimaging and Informatics, Keck School of Medicine, University of Southern California, Marina del Rey, CA, USA
| | - Paul M Thompson
- Imaging Genetics Center, Mark and Mary Stevens Institute for Neuroimaging and Informatics, Keck School of Medicine, University of Southern California, Marina del Rey, CA, USA
| | - Dagmar Timmann
- Department of Neurology and Center for Translational Neuro- and Behavioral Sciences (C-TNBS), Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Bart P C van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
- Department of Neurology, Rijnstate Hospital, Arnhem, Netherlands
| | - Judith van Gaalen
- Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, Netherlands
- Department of Neurology, Rijnstate Hospital, Arnhem, Netherlands
| | - Marcondes C França
- Department of Neurology, University of Campinas (UNICAMP), Campinas, Brazil
- Brazilian Institute of Neuroscience and Neurotechnology, Campinas, Brazil
| | - Ian H Harding
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Monash Biomedical Imaging, Monash University, Clayton, Victoria, Australia
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2
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Park YW, Joers JM, Guo B, Hutter D, Bushara K, Adanyeguh IM, Eberly LE, Öz G, Lenglet C. Corrigendum: Assessment of cerebral and cerebellar white matter microstructure in spinocerebellar ataxias 1, 2, 3, and 6 using diffusion MRI. Front Neurol 2022; 13:1038298. [PMID: 36247785 PMCID: PMC9559733 DOI: 10.3389/fneur.2022.1038298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 09/07/2022] [Indexed: 12/04/2022] Open
Affiliation(s)
- Young Woo Park
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
- *Correspondence: Young Woo Park
| | - James M. Joers
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Bin Guo
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Diane Hutter
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Khalaf Bushara
- Department of Neurology, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Isaac M. Adanyeguh
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Lynn E. Eberly
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Gülin Öz
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Christophe Lenglet
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
- Christophe Lenglet
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3
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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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Rossi M, van der Veen S, Merello M, Tijssen MAJ, van de Warrenburg B. Myoclonus-Ataxia Syndromes: A Diagnostic Approach. Mov Disord Clin Pract 2020; 8:9-24. [PMID: 33426154 DOI: 10.1002/mdc3.13106] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 09/30/2020] [Accepted: 10/14/2020] [Indexed: 12/30/2022] Open
Abstract
Background A myriad of disorders combine myoclonus and ataxia. Most causes are genetic and an increasing number of genes are being associated with myoclonus-ataxia syndromes (MAS), due to recent advances in genetic techniques. A proper etiologic diagnosis of MAS is clinically relevant, given the consequences for genetic counseling, treatment, and prognosis. Objectives To review the causes of MAS and to propose a diagnostic algorithm. Methods A comprehensive and structured literature search following PRISMA criteria was conducted to identify those disorders that may combine myoclonus with ataxia. Results A total of 135 causes of combined myoclonus and ataxia were identified, of which 30 were charted as the main causes of MAS. These include four acquired entities: opsoclonus-myoclonus-ataxia syndrome, celiac disease, multiple system atrophy, and sporadic prion diseases. The distinction between progressive myoclonus epilepsy and progressive myoclonus ataxia poses one of the main diagnostic dilemmas. Conclusions Diagnostic algorithms for pediatric and adult patients, based on clinical manifestations including epilepsy, are proposed to guide the differential diagnosis and corresponding work-up of the most important and frequent causes of MAS. A list of genes associated with MAS to guide genetic testing strategies is provided. Priority should be given to diagnose or exclude acquired or treatable disorders.
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Affiliation(s)
- Malco Rossi
- Movement Disorders Section Neuroscience Department Buenos Aires Argentina.,Argentine National Scientific and Technological Research Council (CONICET) Buenos Aires Argentina
| | - Sterre van der Veen
- Pontificia Universidad Católica Argentina (UCA) Buenos Aires Argentina.,Department of Neurology University of Groningen, University Medical Center Groningen Groningen The Netherlands
| | - Marcelo Merello
- Movement Disorders Section Neuroscience Department Buenos Aires Argentina.,Argentine National Scientific and Technological Research Council (CONICET) Buenos Aires Argentina.,Pontificia Universidad Católica Argentina (UCA) Buenos Aires Argentina
| | - Marina A J Tijssen
- Department of Neurology University of Groningen, University Medical Center Groningen Groningen The Netherlands.,Expertise Center Movement Disorders Groningen University Medical Center Groningen (UMCG) Groningen The Netherlands
| | - Bart van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition & Behaviour Radboud University Medical Center Nijmegen The Netherlands
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5
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Park YW, Joers JM, Guo B, Hutter D, Bushara K, Adanyeguh IM, Eberly LE, Öz G, Lenglet C. Assessment of Cerebral and Cerebellar White Matter Microstructure in Spinocerebellar Ataxias 1, 2, 3, and 6 Using Diffusion MRI. Front Neurol 2020; 11:411. [PMID: 32581994 PMCID: PMC7287151 DOI: 10.3389/fneur.2020.00411] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Accepted: 04/20/2020] [Indexed: 12/13/2022] Open
Abstract
Development of imaging biomarkers for rare neurodegenerative diseases such as spinocerebellar ataxia (SCA) is important to non-invasively track progression of disease pathology and monitor response to interventions. Diffusion MRI (dMRI) has been shown to identify cross-sectional degeneration of white matter (WM) microstructure and connectivity between healthy controls and patients with SCAs, using various analysis methods. In this paper, we present dMRI data in SCAs type 1, 2, 3, and 6 and matched controls, including longitudinal acquisitions at 12–24-month intervals in a subset of the cohort, with up to 5 visits. The SCA1 cohort also contained 3 premanifest patients at baseline, with 2 showing ataxia symptoms at the time of the follow-up scans. We focused on two aspects: first, multimodal evaluation of the dMRI data in a cross-sectional approach, and second, longitudinal trends in dMRI data in SCAs. Three different pipelines were used to perform cross-sectional analyses in WM: region of interest (ROI), tract-based spatial statistics (TBSS), and fixel-based analysis (FBA). We further analyzed longitudinal changes in dMRI metrics throughout the brain using ROI-based analysis. Both ROI and TBSS analyses identified higher mean (MD), axial (AD), and radial (RD) diffusivity and lower fractional anisotropy (FA) in the cerebellum for all SCAs compared to controls, as well as some cerebral alterations in SCA1, 2, and 3. FBA showed lower fiber density (FD) and fiber crossing (FC) regions similar to those identified by ROI and TBSS analyses. FBA also highlighted corticospinal tract (CST) abnormalities, which was not detected by the other two pipelines. Longitudinal ROI-based analysis showed significant increase in AD in the middle cerebellar peduncle (MCP) for patients with SCA1, suggesting that the MCP may be a good candidate region to monitor disease progression. The patient who remained symptom-free throughout the study displayed no microstructural abnormalities. On the other hand, the two patients who were at the premanifest stage at baseline, and showed ataxia symptoms in their follow-up visits, displayed AD values in the MCP that were already in the range of symptomatic patients with SCA1 at their baseline visit, demonstrating that microstructural abnormalities are detectable prior to the onset of ataxia.
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Affiliation(s)
- Young Woo Park
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - James M Joers
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Bin Guo
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Diane Hutter
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Khalaf Bushara
- Department of Neurology, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Isaac M Adanyeguh
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Lynn E Eberly
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States.,Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, MN, United States
| | - Gülin Öz
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
| | - Christophe Lenglet
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN, United States
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6
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Sinha S, Verma S, Singh A, Somvanshi P, Grover A. Simulation Based Investigation of Deleterious nsSNPs in ATXN2 Gene and Its Structural Consequence Toward Spinocerebellar Ataxia. J Cell Biochem 2017; 119:499-510. [PMID: 28612427 DOI: 10.1002/jcb.26209] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/12/2017] [Indexed: 12/11/2022]
Abstract
Spinocerebellar degeneration, termed as ataxia is a neurological disorder of central nervous system, characterized by limb in-coordination and a progressive gait. The patient also demonstrates specific symptoms of muscle weakness, slurring of speech, and decreased vibration senses. Expansion of polyglutamine trinucleotide (CAG) within ATXN2 gene with 35 or more repeats, results in spinocerebellar ataxia type-2. Protein ataxin-2 coded by ATXN2 gene has been reported to have a crucial role in translation of the genetic information through sequestering the histone acetyl transferases (HAT) resulting in a state of hypo-acetylation. In the present study, we have evaluated the outcome for 122 non synonymous single nucleotide polymorphisms (nsSNPs) reported within ATXN2 gene through computational tools such as SIFT, PolyPhen 2.0, PANTHER, I-mutant 2.0, Phd-SNP, Pmut, MutPred. The apo and mutant (L305V and Q339L) form of structures for the ataxin-2 protein were modeled for gaining insights toward 3D spatial arrangement. Further, molecular dynamics simulations and structural analysis were performed to observe the brunt of disease associated nsSNPs toward the strength and secondary properties of ataxin-2 protein structure. Our results showed that, L305V is a highly deleterious and disease causing point substitution. Analysis based on RMSD, RMSF, Rg, SASA, number of hydrogen bonds (NH bonds), covariance matrix trace, projection analysis for eigen vector demonstrated a significant instability and conformation along with rise in mutant flexibility values in comparison to the apo form of ataxin-2 protein. The study provides a blue print of computational methodologies to examine the ataxin-blend SNPs. J. Cell. Biochem. 119: 499-510, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Siddharth Sinha
- Department of Biotechnology, TERI University, New Delhi, 110070, India
| | - Sharad Verma
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Aditi Singh
- Department of Biotechnology, TERI University, New Delhi, 110070, India.,School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Pallavi Somvanshi
- Department of Biotechnology, TERI University, New Delhi, 110070, India
| | - Abhinav Grover
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
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7
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Sinha S, Goyal S, Somvanshi P, Grover A. Mechanistic Insights into the Binding of Class IIa HDAC Inhibitors toward Spinocerebellar Ataxia Type-2: A 3D-QSAR and Pharmacophore Modeling Approach. Front Neurosci 2017; 10:606. [PMID: 28119557 PMCID: PMC5223442 DOI: 10.3389/fnins.2016.00606] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 12/20/2016] [Indexed: 12/18/2022] Open
Abstract
Spinocerebellar ataxia (SCA-2) type-2 is a rare neurological disorder among the nine polyglutamine disorders, mainly caused by polyQ (CAG) trinucleotide repeats expansion within gene coding ataxin-2 protein. The expanded trinucleotide repeats within the ataxin-2 protein sequesters transcriptional cofactors i.e., CREB-binding protein (CBP), Ataxin-2 binding protein 1 (A2BP1) leading to a state of hypo-acetylation and transcriptional repression. Histone de-acetylases inhibitors (HDACi) have been reported to restore transcriptional balance through inhibition of class IIa HDAC's, that leads to an increased acetylation and transcription as demonstrated through in-vivo studies on mouse models of Huntington's. In this study, 61 di-aryl cyclo-propanehydroxamic acid derivatives were used for developing three dimensional (3D) QSAR and pharmacophore models. These models were then employed for screening and selection of anti-ataxia compounds. The chosen QSAR model was observed to be statistically robust with correlation coefficient (r2) value of 0.6774, cross-validated correlation coefficient (q2) of 0.6157 and co-relation coefficient for external test set (pred_r2) of 0.7570. A high F-test value of 77.7093 signified the robustness of the model. Two potential drug leads ZINC 00608101 (SEI) and ZINC 00329110 (ACI) were selected after a coalesce procedure of pharmacophore based screening using the pharmacophore model ADDRR.20 and structural analysis using molecular docking and dynamics simulations. The pharmacophore and the 3D-QSAR model generated were further validated for their screening and prediction ability using the enrichment factor (EF), goodness of hit (GH), and receiver operating characteristics (ROC) curve analysis. The compounds SEI and ACI exhibited a docking score of −10.097 and −9.182 kcal/mol, respectively. An evaluation of binding conformation of ligand-bound protein complexes was performed with MD simulations for a time period of 30 ns along with free energy binding calculations using the g_mmpbsa technique. Prediction of inhibitory activities of the two lead compounds SEI (7.53) and ACI (6.84) using the 3D-QSAR model reaffirmed their inhibitory characteristics as potential anti-ataxia compounds.
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Affiliation(s)
- Siddharth Sinha
- Department of Biotechnology, TERI University New Delhi, India
| | - Sukriti Goyal
- Department of Bioscience and Biotechnology, Banasthali University Tonk, India
| | | | - Abhinav Grover
- School of Biotechnology, Jawaharlal Nehru University New Delhi, India
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8
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Sinha S, Tyagi C, Goyal S, Jamal S, Somvanshi P, Grover A. Fragment based G-QSAR and molecular dynamics based mechanistic simulations into hydroxamic-based HDAC inhibitors against spinocerebellar ataxia. J Biomol Struct Dyn 2016; 34:2281-95. [PMID: 26510381 DOI: 10.1080/07391102.2015.1113386] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Expansion of polyglutamine (CAG) triplets within the coding gene ataxin 2 results in transcriptional repression, forming the molecular basis of the neurodegenerative disorder named spinocerebellar ataxia type-2 (SCA2). HDAC inhibitors (HDACi) have been elements of great interest in polyglutamine disorders such as Huntington's and Ataxia's. In this study, we have selected hydroxamic acid derivatives as HDACi and performed fragment-based G-QSAR, molecular docking studies and molecular dynamics simulations for elucidating the dynamic mode of action of HDACi with His-Asp catalytic dyad of HDAC4. The model was statistically validated to establish its predictive robustness. The model was statistically significant with r(2) value of .6297, cross-validated co-relation coefficient q(2) value of .5905 and pred_r(2) (predicted square co-relation coefficient) value of .85. An F-test value of 56.11 confirms absolute robustness of the model. Two combinatorial libraries comprising of 3180 compounds were created with hydroxamate moiety as the template and their pIC50 activities were predicted based on the G-QSAR model. The combinatorial library created was screened on the basis of predicted activity (pIC50), with two resultant top scoring compounds, HIC and DHC. The interaction of the compounds with His-Asp dyad in terms of H-bond interactions with His802, Asp840, Pro942, and Gly975 residues of HDAC4 was evaluated by docking and 20 ns long molecular dynamics simulations. This study provides valuable leads for structural substitutions required for hydroxamate moiety to exhibit enhanced inhibitory activity against HDAC4. The reported compounds demonstrated good binding and thus can be considered as potent therapeutic leads against ataxia.
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Affiliation(s)
- Siddharth Sinha
- a Department of Biotechnology , TERI University , 10 Institutional Area, Vasant Kunj, New Delhi 110070 , India
| | - Chetna Tyagi
- b Indian Agricultural Research Institute , PUSA Road, New Delhi 110012 , India
| | - Sukriti Goyal
- c Department of Bioscience and Biotechnology , Banasthali University , Tonk , Rajasthan 304022 , India
| | - Salma Jamal
- c Department of Bioscience and Biotechnology , Banasthali University , Tonk , Rajasthan 304022 , India
| | - Pallavi Somvanshi
- a Department of Biotechnology , TERI University , 10 Institutional Area, Vasant Kunj, New Delhi 110070 , India
| | - Abhinav Grover
- d School of Biotechnology , Jawaharlal Nehru University , New Delhi 110067 , India
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9
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A Case of Spinocerebellar Ataxia With a Reversible Splenium Lesion Due to Malnutrition and Vitamin Deficiency. J Clin Neuromuscul Dis 2015; 17:95-7. [PMID: 26583499 DOI: 10.1097/cnd.0000000000000092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Abstract
Heredoataxias are a group of genetic disorders with a cerebellar syndrome as the leading clinical manifestation. The current classification distinguishes heredoataxias according to the trait of inheritance into autosomal dominant, autosomal recessive, X-linked, and maternally inherited heredoataxias. The autosomal dominant heredoataxias are separated into spinocerebellar ataxias (SCA1-8, 10-15, 17-23, 25-30, and dentato-rubro-pallido-luysian atrophy), episodic ataxias (EA1-7), and autosomal dominant mitochondrial heredoataxias (Leigh syndrome, MIRAS, ADOAD, and AD-CPEO). The autosomal recessive ataxias are separated into Friedreich ataxia, ataxia due to vitamin E deficiency, ataxia due to Abeta-lipoproteinemia, Refsum disease, late-onset Tay-Sachs disease, cerebrotendineous xanthomatosis, spinocerebellar ataxia with axonal neuropathy, ataxia telangiectasia, ataxia telangiectasia-like disorder, ataxia with oculomotor apraxia 1 and 2, spastic ataxia of Charlevoix-Saguenay, Cayman ataxia, Marinesco-Sjögren syndrome, and autosomal recessive mitochondrial ataxias (AR-CPEO, SANDO, SCAE, AHS, IOSCA, MEMSA, LBSL CoQ-deficiency, PDC-deficiency). Only two of the heredoataxias, fragile X/tremor/ataxia syndrome, and XLSA/A are transmitted via an X-linked trait. Maternally inherited heredoataxias are due to point mutations in genes encoding for tRNAs, rRNAs, respiratory chain subunits or single large scale deletions/duplications of the mitochondrial DNA and include MELAS, MERRF, KSS, PS, MILS, NARP, and non-syndromic mitochondrial disorders. Treatment of heredoataxias is symptomatic and supportive and may have a beneficial effect in single patients.**Please see page 424 for abbreviation list.
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Koyano S, Yagishita S, Kuroiwa Y, Tanaka F, Uchihara T. Neuropathological staging of spinocerebellar ataxia type 2 by semiquantitative 1C2-positive neuron typing. Nuclear translocation of cytoplasmic 1C2 underlies disease progression of spinocerebellar ataxia type 2. Brain Pathol 2014; 24:599-606. [PMID: 24674145 DOI: 10.1111/bpa.12146] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 03/23/2014] [Indexed: 11/30/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is a hereditary neurodegenerative disorder caused by the expansion of the trinucleotide CAG repeats encoding elongated polyglutamine tract in ataxin-2, the SCA2 gene product. Polyglutamine diseases comprise nine genetic entities, including seven different forms of spinocerebellar ataxias, Huntington's disease, and spinal and bulbar muscular atrophy. These are pathologically characterized by neuronal loss and intranuclear aggregates or inclusions of mutant proteins including expanded polyglutamine in selected neuronal groups. Previously, we examined immunolocalization of ubiquitin, expanded polyglutamine (probed by 1C2 antibody), and ataxin-2 in genetically confirmed SCA2 patients. In the present study, we expanded this approach by distinguishing different patterns of subcellular 1C2 immunoreactivity ("granular cytoplasmic," "cytoplasmic and nuclear" and "nuclear with inclusions.") and by quantifying their regional frequencies in three autopsied SCA2 brains at different stage of the disease. Comparison with neuronal loss and gliosis revealed that overall 1C2 immunoreactivity was paralleled with their severity. Furthermore, appearance of granular cytoplasmic pattern corresponded to early stage, cytoplasmic and nuclear pattern to active stage, and nuclear with inclusions pattern to final stage. We conclude that this 1C2-immunoreactive typing may be useful for evaluating the overall severity and extent of affected regions and estimating the neuropathological stage of SCA2.
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Affiliation(s)
- Shigeru Koyano
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan; Laboratory of Structural Neuropathology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Singh A, Faruq M, Mukerji M, Dwivedi MK, Pruthi S, Kapoor S. Infantile onset spinocerebellar ataxia 2 (SCA2): a clinical report with review of previous cases. J Child Neurol 2014; 29:139-44. [PMID: 24300164 DOI: 10.1177/0883073813509015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Autosomal dominant cerebellar ataxia type I is a heterogeneous group of spinocerebellar ataxias with variable neurologic presentations, with age of onset varying from infancy to adulthood. Autosomal dominant cerebellar ataxia type I is composed mainly of 3 prevalent spinocerebellar ataxia types with different pathogenic loci, specifically spinocerebellar ataxia 1 (6p24-p23), spinocerebellar ataxia 2 (12q24.1), and spinocerebellar ataxia 3 (14q32.1). The shared pathogenic mutational event is the expansion of the CAG repeat that results in polyglutamine extended stretches in the encoded proteins. CAG repeat disorders generally show the phenomenon of anticipation, which is more often associated with paternal transmission. In this report, we describe a patient with infantile-onset spinocerebellar ataxia type 2 (~320 CAG repeat) who inherited the disease from his father (47 CAG repeats). We have summarized the clinical, neuroimaging, electroencephalographic (EEG), and molecular data of previous cases and attempt to highlight the most consistent findings. Our intent is to help treating clinicians to suspect this disorder and to offer timely genetic counseling for a currently potentially untreatable disorder.
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Affiliation(s)
- Ankur Singh
- 1Pediatric Research and Genetic Lab, MAMC Associated Lok Nayak Hospital, New Delhi, India
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13
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The spinocerebellar ataxias: clinical aspects and molecular genetics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 724:351-74. [PMID: 22411256 DOI: 10.1007/978-1-4614-0653-2_27] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Spinocerebellar ataxias (SCAs) are a highly heterogeneous group of inherited neurological disorders, based on clinical characterization alone with variable degrees of cerebellar ataxia often accompanied by additional cerebellar and noncerebellar symptoms which in most cases defy differentiation. Molecular causative deficits in at least 31 genes underlie the clinical symptoms in the SCAs by triggering cerebellar and, very frequently, brain stem dysfunction. The identification of the causative molecular deficits enables the molecular diagnosis of the different SCA subtypes and facilitates genetic counselling. Recent scientific advances are shedding light into developing therapeutic strategies. The scope of this chapter is to provide updated details of the spinocerebellar ataxias with particular emphasis on those aspects aimed at facilitating the clinical and genetic diagnoses.
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Yoon WT, Youn J, Cho JW. Is cerebral white matter involvement helpful in the diagnosis of dentatorubral-pallidoluysian atrophy? J Neurol 2012; 259:1694-7. [DOI: 10.1007/s00415-011-6401-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 12/25/2011] [Accepted: 12/25/2011] [Indexed: 10/14/2022]
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Affiliation(s)
- Georg W J Auburger
- Section Molecular Neurogenetics, Department of Neurology, Johann Wolfgang Goeche University Medical School, Frankfurt/Main, Germany.
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16
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Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominantly inherited, neurodegenerative disease. It can manifest either with a cerebellar syndrome or as Parkinson's syndrome, while later stages involve mainly brainstem, spinal cord and thalamus. This particular atrophy pattern resembles sporadic multi-system-atrophy (MSA) and results in some clinical features indicative of SCA2, such as early saccade slowing, early hyporeflexia, severe tremor of postural or action type, and early myoclonus. For treatment, levodopa is temporarily useful for rigidity/bradykinesia and for tremor, magnesium for muscle cramps, but neuroprotective therapy will depend on the elucidation of pathogenesis. The disease cause lies in the polyglutamine domain of the protein ataxin-2, which can expand in families over successive generations resulting in earlier onset age and faster progression. Genetic testing in SCA2 and other polyglutamine disorders like the well-studied Huntington's disease is now readily available for family planning. Although these disorders differ clinically and in the affected neuron populations, it is not understood how the different polyglutamine proteins mediate such tissue specificity. The neuronal intranuclear inclusion bodies described in other polyglutamine disorders are not frequent in SCA2. For the quite ubiquitously expressed ataxin-2, a subcellular localization at the Golgi, the endoplasmic reticulum and the plasma membrane, in interaction with proteins of mRNA translation and of endocytosis have been observed. As a first victim of SCA2 degeneration, cerebellar Purkinje neurons may be preferentially susceptible to alterations of these subcellular pathways, and therefore our review aims to portray the particular profile of the SCA2 disease process and correlate it to the specific features of ataxin-2.
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Affiliation(s)
- Isabel Lastres-Becker
- Molecular Neurogenetics, Department of Neurology, Klinikum, J. W. Goethe University, Frankfurt am Main, Germany
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Al-Ramahi I, Pérez AM, Lim J, Zhang M, Sorensen R, de Haro M, Branco J, Pulst SM, Zoghbi HY, Botas J. dAtaxin-2 mediates expanded Ataxin-1-induced neurodegeneration in a Drosophila model of SCA1. PLoS Genet 2007; 3:e234. [PMID: 18166084 PMCID: PMC2323314 DOI: 10.1371/journal.pgen.0030234] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Accepted: 11/15/2007] [Indexed: 02/02/2023] Open
Abstract
Spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of neurodegenerative disorders sharing atrophy of the cerebellum as a common feature. SCA1 and SCA2 are two ataxias caused by expansion of polyglutamine tracts in Ataxin-1 (ATXN1) and Ataxin-2 (ATXN2), respectively, two proteins that are otherwise unrelated. Here, we use a Drosophila model of SCA1 to unveil molecular mechanisms linking Ataxin-1 with Ataxin-2 during SCA1 pathogenesis. We show that wild-type Drosophila Ataxin-2 (dAtx2) is a major genetic modifier of human expanded Ataxin-1 (Ataxin-1[82Q]) toxicity. Increased dAtx2 levels enhance, and more importantly, decreased dAtx2 levels suppress Ataxin-1[82Q]-induced neurodegeneration, thereby ruling out a pathogenic mechanism by depletion of dAtx2. Although Ataxin-2 is normally cytoplasmic and Ataxin-1 nuclear, we show that both dAtx2 and hAtaxin-2 physically interact with Ataxin-1. Furthermore, we show that expanded Ataxin-1 induces intranuclear accumulation of dAtx2/hAtaxin-2 in both Drosophila and SCA1 postmortem neurons. These observations suggest that nuclear accumulation of Ataxin-2 contributes to expanded Ataxin-1-induced toxicity. We tested this hypothesis engineering dAtx2 transgenes with nuclear localization signal (NLS) and nuclear export signal (NES). We find that NLS-dAtx2, but not NES-dAtx2, mimics the neurodegenerative phenotypes caused by Ataxin-1[82Q], including repression of the proneural factor Senseless. Altogether, these findings reveal a previously unknown functional link between neurodegenerative disorders with common clinical features but different etiology.
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Affiliation(s)
- Ismael Al-Ramahi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Departamento de Biología, Facultad de Ciencias-University Autonoma de Madrid, Madrid, Spain
| | - Alma M Pérez
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Janghoo Lim
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Minghang Zhang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Rie Sorensen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Maria de Haro
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Joana Branco
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Stefan M Pulst
- Division of Neurology, Cedars-Sinai Medical Center; Departments of Medicine and Neurobiology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Huda Y Zoghbi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas, United States of America
| | - Juan Botas
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- * To whom correspondence should be addressed. E-mail:
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Huynh DP, Nguyen DT, Pulst-Korenberg JB, Brice A, Pulst SM. Parkin is an E3 ubiquitin-ligase for normal and mutant ataxin-2 and prevents ataxin-2-induced cell death. Exp Neurol 2006; 203:531-41. [PMID: 17097639 PMCID: PMC2788988 DOI: 10.1016/j.expneurol.2006.09.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 09/12/2006] [Accepted: 09/18/2006] [Indexed: 11/18/2022]
Abstract
Expansion of the polyQ repeat in ataxin-2 results in degeneration of Purkinje neurons and other neuronal groups including the substantia nigra in patients with spinocerebellar ataxia type 2 (SCA2). In animal and cell models, overexpression of mutant ataxin-2 induces cell dysfunction and death, but little is known about steady-state levels of normal and mutant ataxin-2 and cellular mechanisms regulating their abundance. Based on preliminary findings that ataxin-2 interacted with parkin, an E3 ubiquitin ligase mutated in an autosomal recessive form of Parkinsonism, we sought to determine whether parkin played a role in regulating the steady-state levels of ataxin-2. Parkin interacted with the N-terminal half of normal and mutant ataxin-2, and ubiquitinated the full-length form of both wild-type and mutant ataxin-2. Parkin also regulated the steady-state levels of endogenous ataxin-2 in PC12 cells with regulatable parkin expression. Parkin reduced abnormalities in Golgi morphology induced by mutant ataxin-2 and decreased ataxin-2 induced cytotoxicity. In brains of SCA2 patients, parkin labeled cytoplasmic ataxin-2 aggregates in Purkinje neurons. These studies suggest a role for parkin in regulating the intracellular levels of both wild-type and mutant ataxin-2, and in rescuing cells from ataxin-2-induced cytotoxicity. The role of parkin variants in modifying the SCA2 phenotype and its use as a therapeutic target should be further investigated.
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Affiliation(s)
- Duong P. Huynh
- Rose Moss Laboratory for Parkinson and Neurodegenerative Diseases, Burns and Allen Research Institute, and Division of Neurology, Cedars-Sinai Medical Center, David Geffen School of Medicine at UCLA
- Department of Medicine, David Geffen School of Medicine at UCLA
| | - Dung T. Nguyen
- Rose Moss Laboratory for Parkinson and Neurodegenerative Diseases, Burns and Allen Research Institute, and Division of Neurology, Cedars-Sinai Medical Center, David Geffen School of Medicine at UCLA
| | - Johannes B. Pulst-Korenberg
- Rose Moss Laboratory for Parkinson and Neurodegenerative Diseases, Burns and Allen Research Institute, and Division of Neurology, Cedars-Sinai Medical Center, David Geffen School of Medicine at UCLA
| | - Alexis Brice
- INSERM U289 and Département de Génétique, Cytogénétique et Embryologie, Goupe Hospitalier Pitié-Salpêtrière, 47, Bd de l'Hôpital, 75651 Paris Cedex 13 France
| | - Stefan-M. Pulst
- Rose Moss Laboratory for Parkinson and Neurodegenerative Diseases, Burns and Allen Research Institute, and Division of Neurology, Cedars-Sinai Medical Center, David Geffen School of Medicine at UCLA
- Department of Neurobiology, David Geffen School of Medicine at UCLA
- Corresponding Author: Stefan-M Pulst, MD, 8700 Beverly Blvd, Davis Research Blvd, Room 2091, Phone: 310-423-5166 Fax: 310-423-0148,
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Masciullo M, Modoni A, Pomponi MG, Tartaglione T, Falsini B, Tonali P, Silvestri G. Evidence of white matter involvement in SCA 7. J Neurol 2006; 254:536-8. [PMID: 16988791 DOI: 10.1007/s00415-006-0274-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 02/21/2006] [Accepted: 02/23/2006] [Indexed: 10/24/2022]
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