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MacIver CL, Jones D, Green K, Szewczyk-Krolikowski K, Doring A, Tax CMW, Peall KJ. White Matter Microstructural Changes Using Ultra-Strong Diffusion Gradient MRI in Adult-Onset Idiopathic Focal Cervical Dystonia. Neurology 2024; 103:e209695. [PMID: 39110927 PMCID: PMC11319067 DOI: 10.1212/wnl.0000000000209695] [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: 02/08/2024] [Accepted: 05/28/2024] [Indexed: 08/15/2024] Open
Abstract
BACKGROUND AND OBJECTIVES Adult-onset idiopathic focal cervical dystonia (AOIFCD) involves abnormal posturing of the cervical musculature and, in some individuals, an associated head tremor. Existing neuroimaging studies have implicated key motor networks. However, measures used to date lack specificity toward underlying pathophysiologic differences. We aim to assess white matter motor pathways for localized, microstructural differences, which may aid in understanding underlying mechanisms. METHODS Individuals diagnosed with AOIFCD and an age- and sex-matched control group were prospectively recruited through the Welsh Movement Disorders Research Network. All participants underwent in-depth clinical phenotyping and MRI (structural and diffusion sequences) using ultra-strong diffusion gradients. Tractography (whole-tract median values) and tractometry (along tract profiling) were performed for key white matter motor pathways assessing diffusion kurtosis imaging (DKI), neurite orientation dispersion and density imaging (NODDI), and standard model parameters. Groups were compared using linear model analysis with Bonferroni multiple comparison correction. RESULTS Fifty participants with AOIFCD and 30 healthy control participants were recruited, with 46 with AOIFCD and 30 healthy controls included for analysis (33 without head tremor, 13 with head tremor). Significant differences were observed in the anterior thalamic radiations (lower mid-tract fractional anisotropy [estimate = -0.046, p = 3.07 × 10-3], radial kurtosis [estimate = -0.165, p = 1.42 × 10-4], f-intra-axonal signal fraction [estimate = -0.044, p = 2.78 × 10-3], p2 orientation coherence [estimate = -0.043, p = 1.64 × 10-3], higher Orientation Dispersion Index [ODI, estimate = 0.023, p = 2.22 × 10-3]) and thalamopremotor tracts (higher mid-tract mean kurtosis [estimate = 0.064, p = 7.56 × 10-4], lower Neurite Density Index [estimate = 0.062, p = 2.1 × 10-3], higher distal tract ODI [estimate = 0.062, p = 3.1 × 10-3], lower f [estimate = -0.1, p = 2.3 × 10-3], and striatopremotor tracts [proximal lower f: estimate = -0.075, p = 1.06 × 10-3]). These measures correlated with clinical measures: dystonia duration (right thalamopremotor distal ODI: r = -0.9, p = 1.29 × 10-14), psychiatric symptoms (obsessive compulsive symptoms: left anterior thalamic radiation p2 r = 0.92, p = 2.797 × 10-11), sleep quality (Sleep Disorders Questionnaire Score: left anterior thalamic radiation ODI: r = -0.84, p = 4.84 × 10-11), pain (left anterior thalamic radiation ODI: r = -0.89, p = 1.4 × 10-13), and cognitive functioning (paired associated learning task p2, r = 0.94, p = 6.68 × 10-20). DISCUSSION Overall, localized microstructural differences were identified within tracts linking the prefrontal and premotor cortices with thalamic and basal ganglia regions, suggesting pathophysiologic processes involve microstructural aberrances of motor system modulatory pathways, particularly involving intra-axonal and fiber orientation dispersion measures.
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Affiliation(s)
- Claire L MacIver
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Derek Jones
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Katy Green
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Konrad Szewczyk-Krolikowski
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Andre Doring
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Chantal M W Tax
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
| | - Kathryn J Peall
- From the Cardiff University Brain Research Imaging Centre (C.L.M., D.J., K.G., A.D., C.M.W.T.), Cardiff University; Neuroscience and Mental Health Research Institute (C.L.M., K.J.P.), Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine; North Bristol NHS Trust (K.S.-K.), United Kingdom; and Image Sciences Institute (C.M.W.T.), University Medical Center Utrecht, the Netherlands
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Loução R, Burkhardt J, Wirths J, Kabbasch C, Dembek TA, Heiden P, Cirak S, Al-Fatly B, Treuer H, Visser-Vandewalle V, Hoevels M, Koy A. Diffusion tensor imaging in pediatric patients with dystonia. Neuroimage 2024; 287:120507. [PMID: 38244876 DOI: 10.1016/j.neuroimage.2024.120507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 12/15/2023] [Accepted: 01/03/2024] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND Childhood-onset dystonia is often progressive and severely impairs a child´s life. The pathophysiology is very heterogeneous and treatment responses vary in patients with dystonia. Factors influencing treatment effects remain to be elucidated. We hypothesize that differences in brain connectivity and fiber coherence contribute to the heterogeneity in treatment response among pediatric patients with inherited and acquired dystonia. METHODS Twenty patients with childhood-onset dystonia were retrospectively recruited including twelve patients with inherited or idiopathic, and eight patients with acquired dystonia (mean age 10 years; 8 female/12 male). Fiber density between the internal part of the globus pallidus and selective target regions, as well as the diffusion measures of fractional anisotropy (FA) and mean diffusivity (MD) were analyzed and compared between different etiologies. RESULTS Patients with acquired dystonia presented higher fiber density to the premotor cortex and putamen and lower FA values in the thalamus compared to patients with inherited/idiopathic dystonia. MD in the premotor cortex was higher in patients with acquired dystonia, while it was lower in the thalamus. CONCLUSION Diffusion MRI reveals microstructural and network alterations in patients with dystonia of different etiologies.
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Affiliation(s)
- Ricardo Loução
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany; Department of Neurosurgery, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.
| | - Julia Burkhardt
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Jochen Wirths
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Christoph Kabbasch
- Department of Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Till A Dembek
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Petra Heiden
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany; Department of Neurosurgery, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Sebahattin Cirak
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Bassam Al-Fatly
- Department of Neurology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Harald Treuer
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Veerle Visser-Vandewalle
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Mauritius Hoevels
- Department of Stereotactic and Functional Neurosurgery, Faculty of Medicine and University Hospital Cologne, Kerpener Straße 62, Cologne 50937, Germany
| | - Anne Koy
- Department of Neurology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
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Battistella G, Simonyan K. Clinical Implications of Dystonia as a Neural Network Disorder. ADVANCES IN NEUROBIOLOGY 2023; 31:223-240. [PMID: 37338705 DOI: 10.1007/978-3-031-26220-3_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
Isolated dystonia is a neurological disorder of diverse etiology, multifactorial pathophysiology, and wide spectrum of clinical presentations. We review the recent neuroimaging advances that led to the conceptualization of dystonia as a neural network disorder and discuss how current knowledge is shaping the identification of biomarkers of dystonia and the development of novel pharmacological therapies.
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Affiliation(s)
- Giovanni Battistella
- Department of Otolaryngology - Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, USA
| | - Kristina Simonyan
- Department of Otolaryngology - Head and Neck Surgery, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, USA.
- Department of Neurology, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA.
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4
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MacIver CL, Tax CMW, Jones DK, Peall KJ. Structural magnetic resonance imaging in dystonia: A systematic review of methodological approaches and findings. Eur J Neurol 2022; 29:3418-3448. [PMID: 35785410 PMCID: PMC9796340 DOI: 10.1111/ene.15483] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 01/02/2023]
Abstract
BACKGROUND AND PURPOSE Structural magnetic resonance techniques have been widely applied in neurological disorders to better understand tissue changes, probing characteristics such as volume, iron deposition and diffusion. Dystonia is a hyperkinetic movement disorder, resulting in abnormal postures and pain. Its pathophysiology is poorly understood, with normal routine clinical imaging in idiopathic forms. More advanced tools provide an opportunity to identify smaller scale structural changes which may underpin pathophysiology. This review aims to provide an overview of methodological approaches undertaken in structural brain imaging of dystonia cohorts, and to identify commonly identified pathways, networks or regions that are implicated in pathogenesis. METHODS Structural magnetic resonance imaging studies of idiopathic and genetic forms of dystonia were systematically reviewed. Adhering to strict inclusion and exclusion criteria, PubMed and Embase databases were searched up to January 2022, with studies reviewed for methodological quality and key findings. RESULTS Seventy-seven studies were included, involving 1945 participants. The majority of studies employed diffusion tensor imaging (DTI) (n = 45) or volumetric analyses (n = 37), with frequently implicated areas of abnormality in the brainstem, cerebellum, basal ganglia and sensorimotor cortex and their interconnecting white matter pathways. Genotypic and motor phenotypic variation emerged, for example fewer cerebello-thalamic tractography streamlines in genetic forms than idiopathic and higher grey matter volumes in task-specific than non-task-specific dystonias. DISCUSSION Work to date suggests microstructural brain changes in those diagnosed with dystonia, although the underlying nature of these changes remains undetermined. Employment of techniques such as multiple diffusion weightings or multi-exponential relaxometry has the potential to enhance understanding of these differences.
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Affiliation(s)
- Claire L. MacIver
- Neuroscience and Mental Health Research InstituteDivision of Psychological Medicine and Clinical NeurosciencesCardiff University School of MedicineCardiffUK,Cardiff University Brain Imaging Centre (CUBRIC)Cardiff UniversityCardiffUK
| | - Chantal M. W. Tax
- Cardiff University Brain Imaging Centre (CUBRIC)Cardiff UniversityCardiffUK,Image Sciences InstituteUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Derek K. Jones
- Cardiff University Brain Imaging Centre (CUBRIC)Cardiff UniversityCardiffUK
| | - Kathryn J. Peall
- Neuroscience and Mental Health Research InstituteDivision of Psychological Medicine and Clinical NeurosciencesCardiff University School of MedicineCardiffUK
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5
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Yellajoshyula D, Rogers AE, Kim AJ, Kim S, Pappas SS, Dauer WT. A pathogenic DYT-THAP1 dystonia mutation causes hypomyelination and loss of YY1 binding. Hum Mol Genet 2022; 31:1096-1104. [PMID: 34686877 PMCID: PMC8976427 DOI: 10.1093/hmg/ddab310] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/27/2021] [Accepted: 10/19/2021] [Indexed: 12/24/2022] Open
Abstract
Dystonia is a disabling disease that manifests as prolonged involuntary twisting movements. DYT-THAP1 is an inherited form of isolated dystonia caused by mutations in THAP1 encoding the transcription factor THAP1. The phe81leu (F81L) missense mutation is representative of a category of poorly understood mutations that do not occur on residues critical for DNA binding. Here, we demonstrate that the F81L mutation (THAP1F81L) impairs THAP1 transcriptional activity and disrupts CNS myelination. Strikingly, THAP1F81L exhibits normal DNA binding but causes a significantly reduced DNA binding of YY1, its transcriptional partner that also has an established role in oligodendrocyte lineage progression. Our results suggest a model of molecular pathogenesis whereby THAP1F81L normally binds DNA but is unable to efficiently organize an active transcription complex.
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Affiliation(s)
| | - Abigail E Rogers
- Molecular Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Audrey J Kim
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sumin Kim
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Samuel S Pappas
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - William T Dauer
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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Yellajoshyula D, Pappas SS, Dauer WT. Oligodendrocyte and Extracellular Matrix Contributions to Central Nervous System Motor Function: Implications for Dystonia. Mov Disord 2022; 37:456-463. [PMID: 34989453 PMCID: PMC11152458 DOI: 10.1002/mds.28892] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/17/2021] [Accepted: 12/03/2021] [Indexed: 12/18/2022] Open
Abstract
The quest to elucidate nervous system function and dysfunction in disease has focused largely on neurons and neural circuits. However, fundamental aspects of nervous system development, function, and plasticity are regulated by nonneuronal elements, including glial cells and the extracellular matrix (ECM). The rapid rise of genomics and neuroimaging techniques in recent decades has highlighted neuronal-glial interactions and ECM as a key component of nervous system development, plasticity, and function. Abnormalities of neuronal-glial interactions have been understudied but are increasingly recognized to play a key role in many neurodevelopmental disorders. In this report, we consider the role of myelination and the ECM in the development and function of central nervous system motor circuits and the neurodevelopmental disease dystonia. © 2022 International Parkinson and Movement Disorder Society.
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Affiliation(s)
| | - Samuel S Pappas
- Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - William T Dauer
- Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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Huang X, Lin J, Shang H, Yang J. Voxel-based meta-analysis of gray matter abnormalities in idiopathic dystonia. J Neurol 2022; 269:2862-2873. [PMID: 35013788 DOI: 10.1007/s00415-022-10961-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/03/2022] [Accepted: 01/04/2022] [Indexed: 02/05/2023]
Abstract
BACKGROUND Neuroimaging studies have reported gray matter changes in patients with idiopathic dystonia but with considerable variations. Here, we aimed to investigate the convergence of dystonia-related gray matter changes across studies. METHODS The whole brain voxel-based morphometry studies comparing idiopathic dystonia and healthy controls were systematically searched in the PubMed, Web of Science and Embase. Meta-analysis of gray matter changes was performed using the anisotropic effect size-based signed differential mapping. RESULTS Twenty-eight studies comparing 701 idiopathic dystonia patients and 712 healthy controls were included in the meta-analysis. Compared to healthy controls, idiopathic dystonia patients showed increased gray matter in bilateral precentral and postcentral gyri, bilateral putamen and pallidum, right insula, and left supramarginal gyrus, while decreased gray matter in bilateral temporal poles, bilateral supplementary motor areas, right angular gyrus, inferior parietal gyrus and precuneus, left insula and inferior frontal gyrus. These findings remained robust in the jackknife sensitivity analysis, and no significant heterogeneity was detected. Subgroup analyses of different phenotypes of dystonia were performed to further confirm the above findings. CONCLUSION The meta-analysis showed that consistent widespread gray matter abnormalities were shared in different subtypes of idiopathic dystonia and were not restricted to the corticostriatal circuits.
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Affiliation(s)
- Xiang Huang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Junyu Lin
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Huifang Shang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jing Yang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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Domingo A, Yadav R, Shah S, Hendriks WT, Erdin S, Gao D, O'Keefe K, Currall B, Gusella JF, Sharma N, Ozelius LJ, Ehrlich ME, Talkowski ME, Bragg DC. Dystonia-specific mutations in THAP1 alter transcription of genes associated with neurodevelopment and myelin. Am J Hum Genet 2021; 108:2145-2158. [PMID: 34672987 PMCID: PMC8595948 DOI: 10.1016/j.ajhg.2021.09.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/27/2021] [Indexed: 12/28/2022] Open
Abstract
Dystonia is a neurologic disorder associated with an increasingly large number of genetic variants in many genes, resulting in characteristic disturbances in volitional movement. Dissecting the relationships between these mutations and their functional outcomes is critical in understanding the pathways that drive dystonia pathogenesis. Here we established a pipeline for characterizing an allelic series of dystonia-specific mutations. We used this strategy to investigate the molecular consequences of genetic variation in THAP1, which encodes a transcription factor linked to neural differentiation. Multiple pathogenic mutations associated with dystonia cluster within distinct THAP1 functional domains and are predicted to alter DNA-binding properties and/or protein interactions differently, yet the relative impact of these varied changes on molecular signatures and neural deficits is unclear. To determine the effects of these mutations on THAP1 transcriptional activity, we engineered an allelic series of eight alterations in a common induced pluripotent stem cell background and differentiated these lines into a panel of near-isogenic neural stem cells (n = 94 lines). Transcriptome profiling followed by joint analysis of the most robust signatures across mutations identified a convergent pattern of dysregulated genes functionally related to neurodevelopment, lysosomal lipid metabolism, and myelin. On the basis of these observations, we examined mice bearing Thap1-disruptive alleles and detected significant changes in myelin gene expression and reduction of myelin structural integrity relative to control mice. These results suggest that deficits in neurodevelopment and myelination are common consequences of dystonia-associated THAP1 mutations and highlight the potential role of neuron-glial interactions in the pathogenesis of dystonia.
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Affiliation(s)
- Aloysius Domingo
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Rachita Yadav
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Shivangi Shah
- The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - William T Hendriks
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Serkan Erdin
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Dadi Gao
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Kathryn O'Keefe
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Benjamin Currall
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - James F Gusella
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA
| | - Nutan Sharma
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Laurie J Ozelius
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Michelle E Ehrlich
- Departments of Neurology, Pediatrics, and Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Michael E Talkowski
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA; Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA.
| | - D Cristopher Bragg
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; The Collaborative Center for X-Linked Dystonia-Parkinsonism, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA.
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9
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Caffall ZF, Wilkes BJ, Hernández-Martinez R, Rittiner JE, Fox JT, Wan KK, Shipman MK, Titus SA, Zhang YQ, Patnaik S, Hall MD, Boxer MB, Shen M, Li Z, Vaillancourt DE, Calakos N. The HIV protease inhibitor, ritonavir, corrects diverse brain phenotypes across development in mouse model of DYT-TOR1A dystonia. Sci Transl Med 2021; 13:13/607/eabd3904. [PMID: 34408078 DOI: 10.1126/scitranslmed.abd3904] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 12/14/2020] [Accepted: 06/03/2021] [Indexed: 12/22/2022]
Abstract
Dystonias are a group of chronic movement-disabling disorders for which highly effective oral medications or disease-modifying therapies are lacking. The most effective treatments require invasive procedures such as deep brain stimulation. In this study, we used a high-throughput assay based on a monogenic form of dystonia, DYT1 (DYT-TOR1A), to screen a library of compounds approved for use in humans, the NCATS Pharmaceutical Collection (NPC; 2816 compounds), and identify drugs able to correct mislocalization of the disease-causing protein variant, ∆E302/3 hTorsinA. The HIV protease inhibitor, ritonavir, was among 18 compounds found to normalize hTorsinA mislocalization. Using a DYT1 knock-in mouse model to test efficacy on brain pathologies, we found that ritonavir restored multiple brain abnormalities across development. Ritonavir acutely corrected striatal cholinergic interneuron physiology in the mature brain and yielded sustained correction of diffusion tensor magnetic resonance imaging signals when delivered during a discrete early developmental window. Mechanistically, we found that, across the family of HIV protease inhibitors, efficacy correlated with integrated stress response activation. These preclinical results identify ritonavir as a drug candidate for dystonia with disease-modifying potential.
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Affiliation(s)
- Zachary F Caffall
- Department of Neurology, Duke University Medical Center, Durham, NC 27715, USA
| | - Bradley J Wilkes
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA
| | | | - Joseph E Rittiner
- Department of Neurology, Duke University Medical Center, Durham, NC 27715, USA
| | - Jennifer T Fox
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Kanny K Wan
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Miranda K Shipman
- Department of Neurology, Duke University Medical Center, Durham, NC 27715, USA
| | - Steven A Titus
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Ya-Qin Zhang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Samarjit Patnaik
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Matthew D Hall
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Matthew B Boxer
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - Zhuyin Li
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, USA
| | - David E Vaillancourt
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA.,Department of Neurology, Fixel Institute for Neurological Diseases, McKnight Brain Institute, University of Florida, Gainesville, FL 32611, USA
| | - Nicole Calakos
- Department of Neurology, Duke University Medical Center, Durham, NC 27715, USA. .,Department of Neurobiology, Duke University Medical Center, Durham, NC 27715, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC 27715, USA.,Duke Institute for Brain Sciences, Duke University, Durham, NC 27715, USA
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10
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Knorr S, Rauschenberger L, Pasos UR, Friedrich MU, Peach RL, Grundmann-Hauser K, Ott T, O'Leary A, Reif A, Tovote P, Volkmann J, Ip CW. The evolution of dystonia-like movements in TOR1A rats after transient nerve injury is accompanied by dopaminergic dysregulation and abnormal oscillatory activity of a central motor network. Neurobiol Dis 2021; 154:105337. [PMID: 33753289 DOI: 10.1016/j.nbd.2021.105337] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/08/2021] [Accepted: 03/17/2021] [Indexed: 12/25/2022] Open
Abstract
TOR1A is the most common inherited form of dystonia with still unclear pathophysiology and reduced penetrance of 30-40%. ∆ETorA rats mimic the TOR1A disease by expression of the human TOR1A mutation without presenting a dystonic phenotype. We aimed to induce dystonia-like symptoms in male ∆ETorA rats by peripheral nerve injury and to identify central mechanism of dystonia development. Dystonia-like movements (DLM) were assessed using the tail suspension test and implementing a pipeline of deep learning applications. Neuron numbers of striatal parvalbumin+, nNOS+, calretinin+, ChAT+ interneurons and Nissl+ cells were estimated by unbiased stereology. Striatal dopaminergic metabolism was analyzed via in vivo microdialysis, qPCR and western blot. Local field potentials (LFP) were recorded from the central motor network. Deep brain stimulation (DBS) of the entopeduncular nucleus (EP) was performed. Nerve-injured ∆ETorA rats developed long-lasting DLM over 12 weeks. No changes in striatal structure were observed. Dystonic-like ∆ETorA rats presented a higher striatal dopaminergic turnover and stimulus-induced elevation of dopamine efflux compared to the control groups. Higher LFP theta power in the EP of dystonic-like ∆ETorA compared to wt rats was recorded. Chronic EP-DBS over 3 weeks led to improvement of DLM. Our data emphasizes the role of environmental factors in TOR1A symptomatogenesis. LFP analyses indicate that the pathologically enhanced theta power is a physiomarker of DLM. This TOR1A model replicates key features of the human TOR1A pathology on multiple biological levels and is therefore suited for further analysis of dystonia pathomechanism.
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Affiliation(s)
- Susanne Knorr
- Department of Neurology, University Hospital of Würzburg, 97080, Germany
| | | | - Uri Ramirez Pasos
- Department of Neurology, University Hospital of Würzburg, 97080, Germany
| | | | - Robert L Peach
- Department of Neurology, University Hospital of Würzburg, 97080, Germany
| | - Kathrin Grundmann-Hauser
- Institute for Medical Genetics and Applied Genomics, University of Tübingen, 72076, Germany; Centre for Rare Diseases, University of Tübingen, 72076, Germany
| | - Thomas Ott
- Institute for Medical Genetics and Applied Genomics, University of Tübingen, 72076, Germany; Core Facility Transgenic Animals, University Hospital of Tübingen, 72076, Germany
| | - Aet O'Leary
- Department of Psychiatry, Psychosomatic Medicine, and Psychotherapy, University Hospital Frankfurt, 60528, Germany
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine, and Psychotherapy, University Hospital Frankfurt, 60528, Germany
| | - Philip Tovote
- Systems Neurobiology, Institute of Clinical Neurobiology, University Hospital of Würzburg, Versbacher Straße 5, 97080, Germany
| | - Jens Volkmann
- Department of Neurology, University Hospital of Würzburg, 97080, Germany
| | - Chi Wang Ip
- Department of Neurology, University Hospital of Würzburg, 97080, Germany.
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11
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Contemporary functional neuroanatomy and pathophysiology of dystonia. J Neural Transm (Vienna) 2021; 128:499-508. [PMID: 33486625 PMCID: PMC8099808 DOI: 10.1007/s00702-021-02299-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 01/01/2021] [Indexed: 12/11/2022]
Abstract
Dystonia is a disabling movement disorder characterized by abnormal postures or patterned and repetitive movements due to co-contraction of muscles in proximity to muscles desired for a certain movement. Important and well-established pathophysiological concepts are the impairment of sensorimotor integration, a loss of inhibitory control on several levels of the central nervous system and changes in synaptic plasticity. These mechanisms collectively contribute to an impairment of the gating function of the basal ganglia which results in an insufficient suppression of noisy activity and an excessive activation of cortical areas. In addition to this traditional view, a plethora of animal, genetic, imaging and electrophysiological studies highlight the role of the (1) cerebellum, (2) the cerebello-thalamic connection and (3) the functional interplay between basal ganglia and the cerebellum in the pathophysiology of dystonia. Another emerging topic is the better understanding of the microarchitecture of the striatum and its implications for dystonia. The striosomes are of particular interest as they likely control the dopamine release via inhibitory striato-nigral projections. Striosomal dysfunction has been implicated in hyperkinetic movement disorders including dystonia. This review will provide a comprehensive overview about the current understanding of the functional neuroanatomy and pathophysiology of dystonia and aims to move the traditional view of a ‘basal ganglia disorder’ to a network perspective with a dynamic interplay between cortex, basal ganglia, thalamus, brainstem and cerebellum.
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12
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Georgescu Margarint EL, Georgescu IA, Zahiu CDM, Tirlea SA, Şteopoaie AR, Zǎgrean L, Popa D, Zǎgrean AM. Reduced Interhemispheric Coherence in Cerebellar Kainic Acid-Induced Lateralized Dystonia. Front Neurol 2020; 11:580540. [PMID: 33329321 PMCID: PMC7719699 DOI: 10.3389/fneur.2020.580540] [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: 08/07/2020] [Accepted: 10/28/2020] [Indexed: 11/13/2022] Open
Abstract
The execution of voluntary muscular activity is controlled by the primary motor cortex, together with the cerebellum and basal ganglia. The synchronization of neural activity in the intracortical network is crucial for the regulation of movements. In certain motor diseases, such as dystonia, this synchrony can be altered in any node of the cerebello-cortical network. Questions remain about how the cerebellum influences the motor cortex and interhemispheric communication. This research aims to study the interhemispheric cortical communication between the motor cortices during dystonia, a neurological movement syndrome consisting of sustained or repetitive involuntary muscle contractions. We pharmacologically induced lateralized dystonia to adult male albino mice by administering low doses of kainic acid on the left cerebellar hemisphere. Using electrocorticography and electromyography, we investigated the power spectral densities, cortico-muscular, and interhemispheric coherence between the right and left motor cortices, before and during dystonia, for five consecutive days. Mice displayed lateralized abnormal motor signs, a reduced general locomotor activity, and a high score of dystonia. The results showed a progressive interhemispheric coherence decrease in low-frequency bands (delta, theta, beta) during the first 3 days. The cortico-muscular coherence of the affected side had a significant increase in gamma bands on days 3 and 4. In conclusion, lateralized cerebellar dysfunction during dystonia was associated with a loss of connectivity in the motor cortices, suggesting a possible cortical compensation to the initial disturbances induced by cerebellar left hemisphere kainate activation by blocking the propagation of abnormal oscillations to the healthy hemisphere. However, the cerebellum is part of several overly complex circuits, therefore other mechanisms can still be involved in this phenomenon.
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Affiliation(s)
| | - Ioana Antoaneta Georgescu
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Carmen Denise Mihaela Zahiu
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Stefan-Alexandru Tirlea
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Alexandru Rǎzvan Şteopoaie
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Leon Zǎgrean
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Daniela Popa
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
- Institut de biologie de l'Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Research University, Paris, France
| | - Ana-Maria Zǎgrean
- Division of Physiology and Neuroscience, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
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13
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Chirumamilla VC, Dresel C, Koirala N, Gonzalez-Escamilla G, Deuschl G, Zeuner KE, Muthuraman M, Groppa S. Structural brain network fingerprints of focal dystonia. Ther Adv Neurol Disord 2019; 12:1756286419880664. [PMID: 31798688 PMCID: PMC6859688 DOI: 10.1177/1756286419880664] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 09/10/2019] [Indexed: 01/02/2023] Open
Abstract
Background: Focal dystonias are severe and disabling movement disorders of a still unclear origin. The structural brain networks associated with focal dystonia have not been well characterized. Here, we investigated structural brain network fingerprints in patients with blepharospasm (BSP) compared with those with hemifacial spasm (HFS), and healthy controls (HC). The patients were also examined following treatment with botulinum neurotoxin (BoNT). Methods: This study included matched groups of 13 BSP patients, 13 HFS patients, and 13 HC. We measured patients using structural-magnetic resonance imaging (MRI) at baseline and after one month BoNT treatment, at time points of maximal and minimal clinical symptom representation, and HC at baseline. Group regional cross-correlation matrices calculated based on grey matter volume were included in graph-based network analysis. We used these to quantify global network measures of segregation and integration, and also looked at local connectivity properties of different brain regions. Results: The networks in patients with BSP were more segregated than in patients with HFS and HC (p < 0.001). BSP patients had increased connectivity in frontal and temporal cortices, including sensorimotor cortex, and reduced connectivity in the cerebellum, relative to both HFS patients and HC (p < 0.05). Compared with HC, HFS patients showed increased connectivity in temporal and parietal cortices and a decreased connectivity in the frontal cortex (p < 0.05). In BSP patients, the connectivity of the frontal cortex diminished after BoNT treatment (p < 0.05). In contrast, HFS patients showed increased connectivity in the temporal cortex and reduced connectivity in cerebellum after BoNT treatment (p < 0.05). Conclusions: Our results show that BSP patients display alterations in both segregation and integration in the brain at the network level. The regional differences identified in the sensorimotor cortex and cerebellum of these patients may play a role in the pathophysiology of focal dystonia. Moreover, symptomatic reduction of hyperkinesia by BoNT treatment was associated with different brain network fingerprints in both BSP and HFS patients.
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Affiliation(s)
- Venkata C Chirumamilla
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Christian Dresel
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Nabin Koirala
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Gabriel Gonzalez-Escamilla
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Günther Deuschl
- Department of Neurology, University Hospital Schleswig-Holstein, University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Kirsten E Zeuner
- Department of Neurology, University Hospital Schleswig-Holstein, University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Muthuraman Muthuraman
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sergiu Groppa
- Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience network (rmn), Johannes-Gutenberg-University Mainz, Langenbeckstr. 1, Mainz, 55131, Germany
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14
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Abstract
Dystonia is a neurological disorder characterized by involuntary, repetitive movements. Although the precise mechanisms of dystonia development remain unknown, the diversity of its clinical phenotypes is thought to be associated with multifactorial pathophysiology, which is linked not only to alterations of brain organization, but also environmental stressors and gene mutations. This chapter will present an overview of the pathophysiology of isolated dystonia through the lens of applications of major neuroimaging methodologies, with links to genetics and environmental factors that play a prominent role in symptom manifestation.
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15
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Weisheit CE, Pappas SS, Dauer WT. Inherited dystonias: clinical features and molecular pathways. HANDBOOK OF CLINICAL NEUROLOGY 2018; 147:241-254. [PMID: 29325615 DOI: 10.1016/b978-0-444-63233-3.00016-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recent decades have witnessed dramatic increases in understanding of the genetics of dystonia - a movement disorder characterized by involuntary twisting and abnormal posture. Hampered by a lack of overt neuropathology, researchers are investigating isolated monogenic causes to pinpoint common molecular mechanisms in this heterogeneous disease. Evidence from imaging, cellular, and murine work implicates deficiencies in dopamine neurotransmission, transcriptional dysregulation, and selective vulnerability of distinct neuronal populations to disease mutations. Studies of genetic forms of dystonia are also illuminating the developmental dependence of disease symptoms that is typical of many forms of the disease. As understanding of monogenic forms of dystonia grows, a clearer picture will develop of the abnormal motor circuitry behind this relatively common phenomenology. This chapter focuses on the current data covering the etiology and epidemiology, clinical presentation, and pathogenesis of four monogenic forms of isolated dystonia: DYT-TOR1A, DYT-THAP1, DYT-GCH1, and DYT-GNAL.
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Affiliation(s)
- Corinne E Weisheit
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Samuel S Pappas
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - William T Dauer
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States.
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16
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Blood AJ, Waugh JL, Münte TF, Heldmann M, Domingo A, Klein C, Breiter HC, Lee LV, Rosales RL, Brüggemann N. Increased insula-putamen connectivity in X-linked dystonia-parkinsonism. NEUROIMAGE-CLINICAL 2017. [PMID: 29527488 PMCID: PMC5842648 DOI: 10.1016/j.nicl.2017.10.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Preliminary evidence from postmortem studies of X-linked dystonia-parkinsonism (XDP) suggests tissue loss may occur first and/or most severely in the striatal striosome compartment, followed later by cell loss in the matrix compartment. However, little is known about how this relates to pathogenesis and pathophysiology. While MRI cannot visualize these striatal compartments directly in humans, differences in relative gradients of afferent cortical connectivity across compartments (weighted toward paralimbic versus sensorimotor cortex, respectively) can be used to infer potential selective loss in vivo. In the current study we evaluated relative connectivity of paralimbic versus sensorimotor cortex with the caudate and putamen in 17 individuals with XDP and 17 matched controls. Although caudate and putamen volumes were reduced in XDP, there were no significant reductions in either “matrix-weighted”, or “striosome-weighted” connectivity. In fact, paralimbic connectivity with the putamen was elevated, rather than reduced, in XDP. This was driven most strongly by elevated putamen connectivity with the anterior insula. There was no relationship of these findings to disease duration or striatal volume, suggesting insula and/or paralimbic connectivity in XDP may develop abnormally and/or increase in the years before symptom onset. Previous work suggested striosomes might degenerate preferentially in early XDP. We developed a DTI tractography method to assess striosome and matrix integrity. Striosomal afferents to putamen were elevated in XDP, despite reduced putamen volume. Connectivity was particularly elevated from the insula (two to three-fold). Striosome connectivity strength was not associated with disease duration.
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Affiliation(s)
- Anne J Blood
- Mood and Motor Control Laboratory, Massachusetts General Hospital (MGH), Charlestown, MA, USA; Laboratory of Neuroimaging and Genetics, MGH, Charlestown, MA, USA; Depts. of Neurology, MGH, Boston, MA, USA; Psychiatry, MGH, Boston, MA, USA; Martinos Center for Biomedical Imaging, Dept. of Radiology, MGH, Charlestown, MA, USA; Harvard Medical School, Boston, MA, USA.
| | - Jeff L Waugh
- Mood and Motor Control Laboratory, Massachusetts General Hospital (MGH), Charlestown, MA, USA; Depts. of Neurology, MGH, Boston, MA, USA; Martinos Center for Biomedical Imaging, Dept. of Radiology, MGH, Charlestown, MA, USA; Division of Child Neurology, Boston Children's Hospital, USA; Harvard Medical School, Boston, MA, USA
| | - Thomas F Münte
- Department of Neurology, University of Lübeck, Lübeck, Germany
| | - Marcus Heldmann
- Department of Neurology, University of Lübeck, Lübeck, Germany
| | - Aloysius Domingo
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Hans C Breiter
- Mood and Motor Control Laboratory, Massachusetts General Hospital (MGH), Charlestown, MA, USA; Laboratory of Neuroimaging and Genetics, MGH, Charlestown, MA, USA; Psychiatry, MGH, Boston, MA, USA; Warren Wright Adolescent Center, Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Lillian V Lee
- XDP Study Group, Philippine Children's Medical Center, Quezon City, Philippines
| | - Raymond L Rosales
- XDP Study Group, Philippine Children's Medical Center, Quezon City, Philippines; Department of Neurology and Psychiatry, Faculty of Medicine and Surgery, University of Santo Tomas, Manila, Philippines
| | - Norbert Brüggemann
- Department of Neurology, University of Lübeck, Lübeck, Germany; Institute of Neurogenetics, University of Lübeck, Lübeck, Germany.
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17
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Abstract
Dystonia is one of the most frequent movement disorders in childhood. It can impede normal motor development and cause significant motor disability. The diagnostic evaluation of childhood dystonia is challenging due to the phenotypic variability and heterogeneous etiologies. Evidence to guide the diagnostic evaluation and treatment is limited. Assessment is primarily directed by clinical history and distinctive examination findings. Neuroimaging is typically necessary to evaluate for acquired or complex inherited dystonias. A trial of levodopa can be both diagnostic and therapeutic in children with dopa-responsive dystonia. However, for the majority of children with early-onset dystonia, treatment is symptomatic with varying efficacy. There is a paucity of therapeutic trials for childhood dystonia and most treatment recommendations are consensus or expert opinion driven. This review summarizes the available evidence and guidelines on the diagnostic evaluation and pharmacological treatment of childhood-onset dystonia and provides practical frameworks to approach both issues based on best evidence.
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18
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Nibbeling EAR, Delnooz CCS, de Koning TJ, Sinke RJ, Jinnah HA, Tijssen MAJ, Verbeek DS. Using the shared genetics of dystonia and ataxia to unravel their pathogenesis. Neurosci Biobehav Rev 2017; 75:22-39. [PMID: 28143763 DOI: 10.1016/j.neubiorev.2017.01.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 12/09/2016] [Accepted: 01/24/2017] [Indexed: 12/13/2022]
Abstract
In this review we explore the similarities between spinocerebellar ataxias and dystonias, and suggest potentially shared molecular pathways using a gene co-expression network approach. The spinocerebellar ataxias are a group of neurodegenerative disorders characterized by coordination problems caused mainly by atrophy of the cerebellum. The dystonias are another group of neurological movement disorders linked to basal ganglia dysfunction, although evidence is now pointing to cerebellar involvement as well. Our gene co-expression network approach identified 99 shared genes and showed the involvement of two major pathways: synaptic transmission and neurodevelopment. These pathways overlapped in the two disorders, with a large role for GABAergic signaling in both. The overlapping pathways may provide novel targets for disease therapies. We need to prioritize variants obtained by whole exome sequencing in the genes associated with these pathways in the search for new pathogenic variants, which can than be used to help in the genetic counseling of patients and their families.
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Affiliation(s)
- Esther A R Nibbeling
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Cathérine C S Delnooz
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Tom J de Koning
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands; University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Richard J Sinke
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Hyder A Jinnah
- Departments of Neurology, Human Genetics and Pediatrics, Emory Clinic, Atlanta, USA
| | - Marina A J Tijssen
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, The Netherlands
| | - Dineke S Verbeek
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands.
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19
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Ismail FY, Fatemi A, Johnston MV. Cerebral plasticity: Windows of opportunity in the developing brain. Eur J Paediatr Neurol 2017; 21:23-48. [PMID: 27567276 DOI: 10.1016/j.ejpn.2016.07.007] [Citation(s) in RCA: 282] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 07/06/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND Neuroplasticity refers to the inherently dynamic biological capacity of the central nervous system (CNS) to undergo maturation, change structurally and functionally in response to experience and to adapt following injury. This malleability is achieved by modulating subsets of genetic, molecular and cellular mechanisms that influence the dynamics of synaptic connections and neural circuitry formation culminating in gain or loss of behavior or function. Neuroplasticity in the healthy developing brain exhibits a heterochronus cortex-specific developmental profile and is heightened during "critical and sensitive periods" of pre and postnatal brain development that enable the construction and consolidation of experience-dependent structural and functional brain connections. PURPOSE In this review, our primary goal is to highlight the essential role of neuroplasticity in brain development, and to draw attention to the complex relationship between different levels of the developing nervous system that are subjected to plasticity in health and disease. Another goal of this review is to explore the relationship between plasticity responses of the developing brain and how they are influenced by critical and sensitive periods of brain development. Finally, we aim to motivate researchers in the pediatric neuromodulation field to build on the current knowledge of normal and abnormal neuroplasticity, especially synaptic plasticity, and their dependence on "critical or sensitive periods" of neural development to inform the design, timing and sequencing of neuromodulatory interventions in order to enhance and optimize their translational applications in childhood disorders of the brain. METHODS literature review. RESULTS We discuss in details five patterns of neuroplasticity expressed by the developing brain: 1) developmental plasticity which is further classified into normal and impaired developmental plasticity as seen in syndromic autism spectrum disorders, 2) adaptive (experience-dependent) plasticity following intense motor skill training, 3) reactive plasticity to pre and post natal CNS injury or sensory deprivation, 4) excessive plasticity (loss of homeostatic regulation) as seen in dystonia and refractory epilepsy, 6) and finally, plasticity as the brain's "Achilles tendon" which induces brain vulnerability under certain conditions such as hypoxic ischemic encephalopathy and epileptic encephalopathy syndromes. We then explore the unique feature of "time-sensitive heightened plasticity responses" in the developing brain in the in the context of neuromodulation. CONCLUSION The different patterns of neuroplasticity and the unique feature of heightened plasticity during critical and sensitive periods are important concepts for researchers and clinicians in the field of pediatric neurology and neurodevelopmental disabilities. These concepts need to be examined systematically in the context of pediatric neuromodulation. We propose that critical and sensitive periods of brain development in health and disease can create "windows of opportunity" for neuromodulatory interventions that are not commonly seen in adult brain and probably augment plasticity responses and improve clinical outcomes.
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Affiliation(s)
- Fatima Yousif Ismail
- Department of neurology and developmental medicine, The Kennedy Krieger Institute, Johns Hopkins Medical Institutions, MD, USA; Department of pediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al- Ain, UAE.
| | - Ali Fatemi
- Departments of Neurology and Pediatrics, The Kennedy Krieger Institute, and Johns Hopkins University School of Medicine, MD, USA
| | - Michael V Johnston
- Departments of Neurology and Pediatrics, The Kennedy Krieger Institute, and Johns Hopkins University School of Medicine, MD, USA
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20
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Brüggemann N, Heldmann M, Klein C, Domingo A, Rasche D, Tronnier V, Rosales RL, Jamora RDG, Lee LV, Münte TF. Neuroanatomical changes extend beyond striatal atrophy in X-linked dystonia parkinsonism. Parkinsonism Relat Disord 2016; 31:91-97. [DOI: 10.1016/j.parkreldis.2016.07.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 07/09/2016] [Accepted: 07/22/2016] [Indexed: 01/09/2023]
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21
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Premi E, Diano M, Gazzina S, Cauda F, Gualeni V, Tinazzi M, Fiorio M, Liberini P, Lazzarini C, Archetti S, Biasiotto G, Turla M, Bertasi V, Cotelli M, Gasparotti R, Padovani A, Borroni B. Functional Connectivity Networks in Asymptomatic and Symptomatic DYT1 Carriers. Mov Disord 2016; 31:1739-1743. [PMID: 27453152 DOI: 10.1002/mds.26725] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 05/25/2016] [Accepted: 06/13/2016] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND DYT1 mutation is characterized by focal to generalized dystonia and incomplete penetrance. To explore the complex perturbations in the different neural networks and the mutual interactions among them, we studied symptomatic and asymptomatic DTY1 mutation carriers by resting-state functional MRI. METHODS A total of 7 symptomatic DYT1, 10 asymptomatic DYT1, and 26 healthy controls were considered. Resting-state functional MRI (Oxford Centre for Functional MRI of the Brain) [FMRIB] Software Library) (FSL) MELODIC, dual regression, (as a toolbox of FSL, with Nets is referred to "networks") (FSLNets) (http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FSLNets) was performed on 9 resting-state neural networks. RESULTS DYT1 mutation signature (symptomatic DYT1 and asymptomatic DYT1) was characterized by increased connectivity in the dorsal attention network and in the left fronto-parietal network. Functional correlates of symptomatic DYT1 patients (symptomatic DYT1 vs healthy controls) showed increased connectivity in the sensorimotor network. DISCUSSION This study argues that DYT1 dystonia is a network disorder, with crucial nodes in sensory-motor integration of posterior parietal structures. A better characterization of cortical networks involved in dystonia is crucial for possible neurophysiological therapeutic interventions. © 2016 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Enrico Premi
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Matteo Diano
- GCS fMRI Koelliker Hospital, Turin, Italy.,Department of Psychology, University of Turin, Turin, Italy
| | - Stefano Gazzina
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Franco Cauda
- GCS fMRI Koelliker Hospital, Turin, Italy.,Department of Psychology, University of Turin, Turin, Italy
| | - Vera Gualeni
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Michele Tinazzi
- Department of Neurological and Movement Sciences, University of Verona, Verona, Italy
| | - Mirta Fiorio
- Department of Neurological and Movement Sciences, University of Verona, Verona, Italy
| | - Paolo Liberini
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Clara Lazzarini
- Neurophysiology Department, University Hospital "Spedali Civili,", Brescia, Italy
| | - Silvana Archetti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.,Biotechnology Laboratory, Department of Diagnostic, "Spedali Civili" Hospital, Brescia, Italy
| | - Giorgio Biasiotto
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.,Biotechnology Laboratory, Department of Diagnostic, "Spedali Civili" Hospital, Brescia, Italy
| | | | | | - Maria Cotelli
- Neurology Unit, Valle Camonica Hospital, Brescia, Italy
| | | | - Alessandro Padovani
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Barbara Borroni
- Centre for Ageing Brain and Neurodegenerative Disorders, Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
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Bhagat SL, Qiu S, Caffall ZF, Wan Y, Pan Y, Rodriguiz RM, Wetsel WC, Badea A, Hochgeschwender U, Calakos N. Mouse model of rare TOR1A variant found in sporadic focal dystonia impairs domains affected in DYT1 dystonia patients and animal models. Neurobiol Dis 2016; 93:137-45. [PMID: 27168150 DOI: 10.1016/j.nbd.2016.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/25/2016] [Accepted: 05/05/2016] [Indexed: 12/13/2022] Open
Abstract
Rare de novo mutations in genes associated with inherited Mendelian disorders are potential contributors to sporadic disease. DYT1 dystonia is an autosomal dominant, early-onset, generalized dystonia associated with an in-frame, trinucleotide deletion (n. delGAG, p. ΔE 302/303) in the Tor1a gene. Here we examine the significance of a rare missense variant in the Tor1a gene (c. 613T>A, p. F205I), previously identified in a patient with sporadic late-onset focal dystonia, by modeling it in mice. Homozygous F205I mice have motor impairment, reduced steady-state levels of TorsinA, altered corticostriatal synaptic plasticity, and prominent brain imaging abnormalities in areas associated with motor function. Thus, the F205I variant causes abnormalities in domains affected in people and/or mouse models with the DYT1 Tor1a mutation (ΔE). Our findings establish the pathological significance of the F205I Tor1a variant and provide a model with both etiological and phenotypic relevance to further investigate dystonia mechanisms.
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Affiliation(s)
- Srishti L Bhagat
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States; Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, United States
| | - Sunny Qiu
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States
| | - Zachary F Caffall
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States
| | - Yehong Wan
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States
| | - Yuanji Pan
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States
| | - Ramona M Rodriguiz
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, United States
| | - William C Wetsel
- Duke Institute of Brain Sciences, United States; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, United States
| | - Alexandra Badea
- Department of Radiology, Duke University Medical Center, Durham, NC 27710, United States
| | - Ute Hochgeschwender
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States
| | - Nicole Calakos
- Department of Neurology, Duke University Medical Center, Durham, NC 27710, United States; Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, United States; Duke Institute of Brain Sciences, United States.
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23
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Pavese N, Tai YF. Genetic and degenerative disorders primarily causing other movement disorders. HANDBOOK OF CLINICAL NEUROLOGY 2016; 135:507-523. [PMID: 27432681 DOI: 10.1016/b978-0-444-53485-9.00025-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this chapter, we will discuss the contributions of structural and functional imaging to the diagnosis and management of genetic and degenerative diseases that lead to the occurrence of movement disorders. We will mainly focus on Huntington's disease, Wilson's disease, dystonia, and neurodegeneration with brain iron accumulation, as they are the more commonly encountered clinical conditions within this group.
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Affiliation(s)
- Nicola Pavese
- Division of Brain Sciences, Imperial College London, UK; Aarhus University, Denmark.
| | - Yen F Tai
- Division of Brain Sciences, Imperial College London, UK
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24
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Weisheit CE, Dauer WT. A novel conditional knock-in approach defines molecular and circuit effects of the DYT1 dystonia mutation. Hum Mol Genet 2015; 24:6459-72. [PMID: 26370418 DOI: 10.1093/hmg/ddv355] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/01/2015] [Indexed: 01/15/2023] Open
Abstract
DYT1 dystonia, the most common inherited form of primary dystonia, is a neurodevelopmental disease caused by a dominant mutation in TOR1A. This mutation ('ΔE') removes a single glutamic acid from the encoded protein, torsinA. The effects of this mutation, at the molecular and circuit levels, and the reasons for its neurodevelopmental onset, remain incompletely understood. To uniquely address key questions of disease pathogenesis, we generated a conditional Tor1a knock-in allele that is converted from wild-type to DYT1 mutant ('induced' ΔE: Tor1a(i-ΔE)), following Cre recombination. We used this model to perform a gene dosage study exploring the effects of the ΔE mutation at the molecular, neuropathological and organismal levels. These analyses demonstrated that ΔE-torsinA is a hypomorphic allele and showed no evidence for any gain-of-function toxic properties. The unique capabilities of this model also enabled us to test a circuit-level hypothesis of DYT1 dystonia, which predicts that expression of the DYT1 genotype (Tor1a(ΔE/+)) selectively within hindbrain structures will produce an overtly dystonic animal. In contrast to this prediction, we find no effect of this anatomic-specific expression of the DYT1 genotype, a finding that has important implications for the interpretation of the human and mouse diffusion tensor-imaging studies upon which it is based. These studies advance understanding of the molecular effects of the ΔE mutation, challenge current concepts of the circuit dysfunction that characterize the disease and establish a powerful tool that will be valuable for future studies of disease pathophysiology.
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Affiliation(s)
| | - William T Dauer
- Department of Neurology and Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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25
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Karimi M, Perlmutter JS. The role of dopamine and dopaminergic pathways in dystonia: insights from neuroimaging. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2015; 5:280. [PMID: 25713747 PMCID: PMC4314610 DOI: 10.7916/d8j101xv] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 01/03/2015] [Indexed: 12/14/2022]
Abstract
Background Dystonia constitutes a heterogeneous group of movement abnormalities, characterized by sustained or intermittent muscle contractions causing abnormal postures. Overwhelming data suggest involvement of basal ganglia and dopaminergic pathways in dystonia. In this review, we critically evaluate recent neuroimaging studies that investigate dopamine receptors, endogenous dopamine release, morphology of striatum, and structural or functional connectivity in cortico-basal ganglia-thalamo-cortical and related cerebellar circuits in dystonia. Method A PubMed search was conducted in August 2014. Results Positron emission tomography (PET) imaging offers strong evidence for altered D2/D3 receptor binding and dopaminergic release in many forms of idiopathic dystonia. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) data reveal likely involvement of related cerebello-thalamo-cortical and sensory-motor networks in addition to basal ganglia. Discussion PET imaging of dopamine receptors or transmitter release remains an effective means to investigate dopaminergic pathways, yet may miss factors affecting dopamine homeostasis and related subcellular signaling cascades that could alter the function of these pathways. fMRI and DTI methods may reveal functional or anatomical changes associated with dysfunction of dopamine-mediated pathways. Each of these methods can be used to monitor target engagement for potential new treatments. PET imaging of striatal phosphodiesterase and development of new selective PET radiotracers for dopamine D3-specific receptors and Mechanistic target of rampamycin (mTOR) are crucial to further investigate dopaminergic pathways. A multimodal approach may have the greatest potential, using PET to identify the sites of molecular pathology and magnetic resonance methods to determine their downstream effects.
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Affiliation(s)
- Morvarid Karimi
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Joel S Perlmutter
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA ; Department of Radiology, Neurobiology, Physical Therapy and Occupational Therapy, Washington University in St. Louis, St. Louis, MO, USA
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26
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Sako W, Uluğ AM, Eidelberg D. Functional Imaging to Study Movement Disorders. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00012-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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27
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Vo A, Sako W, Dewey SL, Eidelberg D, Uluğ AM. 18FDG-microPET and MR DTI findings in Tor1a+/- heterozygous knock-out mice. Neurobiol Dis 2014; 73:399-406. [PMID: 25447231 DOI: 10.1016/j.nbd.2014.10.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 10/23/2014] [Accepted: 10/29/2014] [Indexed: 11/25/2022] Open
Abstract
TorsinA is an important protein in brain development, and plays a role in the regulation of neurite outgrowth and synaptic function. Patients with the most common form of genetic dystonia carry a mutation (DYT1) in one copy of the Tor1a gene, a 3-bp deletion, causing removal of a single glutamic acid from torsinA. Previous imaging studies have shown that abnormal cerebellar metabolism and damaged cerebello-thalamo-cortical pathway contribute to the pathophysiology of DYT1 dystonia. However, how a mutation in one copy of the Tor1a gene causes these abnormalities is not known. We studied Tor1a heterozygous knock-out mice in vivo with FDG-PET and ex vivo with diffusion tensor imaging. We found metabolic abnormalities in cerebellum, caudate-putamen, globus pallidus, sensorimotor cortex and subthalamic nucleus. We also found that FA was increased in caudate-putamen, sensorimotor cortex and brainstem. We compared our findings with a previous imaging study of the Tor1a knock-in mice. Our study suggested that having only one normal copy of Tor1a gene may be responsible for the metabolic abnormalities observed; having a copy of mutant Tor1a, on the other hand, may be responsible for white matter pathway damages seen in DYT1 dystonia subjects.
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Affiliation(s)
- An Vo
- Center for Neurosciences, The Feinstein Institute for Medical Research, NY 11030, USA
| | - Wataru Sako
- Center for Neurosciences, The Feinstein Institute for Medical Research, NY 11030, USA
| | - Stephen L Dewey
- Center for Neurosciences, The Feinstein Institute for Medical Research, NY 11030, USA; Department of Molecular Medicine, Hofstra University, NY 11549, USA; Department of Psychiatry, New York University, NY 10012, USA
| | - David Eidelberg
- Center for Neurosciences, The Feinstein Institute for Medical Research, NY 11030, USA
| | - Aziz M Uluğ
- Center for Neurosciences, The Feinstein Institute for Medical Research, NY 11030, USA; Department of Molecular Medicine, Hofstra University, NY 11549, USA; Department of Radiology, Albert Einstein College of Medicine, NY 10461, USA; Institute of Biomedical Engineering, Boğaziçi University, Istanbul, Turkey.
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28
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Lehéricy S, Tijssen MAJ, Vidailhet M, Kaji R, Meunier S. The anatomical basis of dystonia: current view using neuroimaging. Mov Disord 2014; 28:944-57. [PMID: 23893451 DOI: 10.1002/mds.25527] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 04/06/2013] [Accepted: 05/02/2013] [Indexed: 12/15/2022] Open
Abstract
This review will consider the knowledge that neuroimaging studies have provided to the understanding of the anatomy of dystonia. Major advances have occurred in the use of neuroimaging for dystonia in the past 2 decades. At present, the most developed imaging approaches include whole-brain or region-specific studies of structural or diffusion changes, functional imaging using fMRI or positron emission tomography (PET), and metabolic imaging using fluorodeoxyglucose PET. These techniques have provided evidence that regions other than the basal ganglia are involved in dystonia. In particular, there is increasing evidence that primary dystonia can be viewed as a circuit disorder, involving the basal ganglia-thalamo-cortical and cerebello-thalamo-cortical pathways. This suggests that a better understanding of the dysfunction in each region in the network and their interactions are important topics to address. Current views of interpretation of imaging data as cause or consequence of dystonia, and the postmortem correlates of imaging data are presented. The application of imaging as a tool to monitor therapy and its use as an outcome measure will be discussed. © 2013 Movement Disorder Society.
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Affiliation(s)
- Stéphane Lehéricy
- Institut du Cerveau et de la Moelle (ICM) epiniere, Centre de NeuroImagerie de Recherche (CENIR), Paris, France.
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29
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Oleas J, Yokoi F, DeAndrade MP, Pisani A, Li Y. Engineering animal models of dystonia. Mov Disord 2014; 28:990-1000. [PMID: 23893455 DOI: 10.1002/mds.25583] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 05/25/2013] [Accepted: 05/29/2013] [Indexed: 12/19/2022] Open
Abstract
Dystonia is a neurological disorder characterized by abnormal involuntary movements that are prolonged and often cause twisting and turning. Several genetically modified worms, fruit flies, and rodents have been generated as models of genetic dystonias, in particular DYT1, DYT11, and DYT12 dystonias. Although these models do not show overt dystonic symptoms, the rodent models exhibit motor deficits in specialized behavioral tasks, such as the rotarod and beam-walking tests. For example, in a rodent model of DYT12 dystonia, which is generally stress triggered, motor deficits are observed only after the animal is stressed. Moreover, in a rodent model of DYT1 dystonia, the motor and electrophysiological deficits can be rescued by trihexyphenidyl, a common anticholinergic medication used to treat dystonic symptoms in human patients. Biochemically, the DYT1 and DYT11 animal models also share some similarities to patients, such as a reduction in striatal D2 dopamine receptor and binding activities. In addition, conditional knockout mouse models for DYT1 and DYT11 dystonia demonstrate that loss of the causal dystonia-related proteins in the striatum leads to motor deficits. Interestingly, loss of the DYT1 dystonia causal protein in Purkinje cells shows an improvement in motor performance, suggesting that gene therapy targeting of the cerebellum or intervention in its downstream pathways may be useful. Finally, recent studies using DYT1 dystonia worm and mouse models led to a potential novel therapeutic agent, which is currently undergoing clinical trials. These results indicate that genetic animal models are powerful tools to elucidate the pathophysiology and to further develop new therapeutics for dystonia.
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Affiliation(s)
- Janneth Oleas
- Department of Neurology, College of Medicine, University of Florida, Gainesville, Florida 32610, USA
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30
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Hess CW, Ofori E, Akbar U, Okun MS, Vaillancourt DE. The evolving role of diffusion magnetic resonance imaging in movement disorders. Curr Neurol Neurosci Rep 2013; 13:400. [PMID: 24046183 PMCID: PMC3824956 DOI: 10.1007/s11910-013-0400-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Significant advances have allowed diffusion magnetic resonance imaging (MRI) to evolve into a powerful tool in the field of movement disorders that can be used to study disease states and connectivity between brain regions. Diffusion MRI is a promising potential biomarker for Parkinson's disease and other forms of parkinsonism, and may allow the distinction of different forms of parkinsonism. Techniques such as tractography have contributed to our current thinking regarding the pathophysiology of dystonia and possible mechanisms of penetrance. Diffusion MRI measures could potentially assist in monitoring disease progression in Huntington's disease, and in uncovering the nature of the processes and structures involved the development of essential tremor. The ability to represent structural connectivity in vivo also makes diffusion MRI an ideal adjunctive tool for the surgical treatment of movement disorders. We review recent studies using diffusion MRI in movement disorders research and present the current state of the science as well as future directions.
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Affiliation(s)
- Christopher W. Hess
- Laboratory for Rehabilitation Neuroscience, University of Florida, Gainesville, FL, USA
- University of Florida Center for Movement Disorders & Neurorestoration, Gainesville, FL, USA
- Neurology Service, Malcom Randall VA Medical Center, Gainesville, FL, USA
| | - Edward Ofori
- Laboratory for Rehabilitation Neuroscience, University of Florida, Gainesville, FL, USA
| | - Umer Akbar
- University of Florida Center for Movement Disorders & Neurorestoration, Gainesville, FL, USA
| | - Michael S. Okun
- University of Florida Center for Movement Disorders & Neurorestoration, Gainesville, FL, USA
| | - David E. Vaillancourt
- Laboratory for Rehabilitation Neuroscience, University of Florida, Gainesville, FL, USA
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Lerner RP, Niethammer M, Eidelberg D. Understanding the anatomy of dystonia: determinants of penetrance and phenotype. Curr Neurol Neurosci Rep 2013; 13:401. [PMID: 24114145 PMCID: PMC3883436 DOI: 10.1007/s11910-013-0401-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The dystonias comprise a group of syndromes characterized by prolonged involuntary muscle contractions resulting in repetitive movements and abnormal postures. Primary dystonia has been associated with over 14 different genotypes, most of which follow an autosomal dominant inheritance pattern with reduced penetrance. Independent of etiology, the disease is characterized by extensive variability in disease phenotype and clinical severity. Recent neuroimaging studies investigating this phenomenon in manifesting and non-manifesting genetic carriers of dystonia have discovered microstructural integrity differences in the cerebello-thalamo-cortical tract in both groups related to disease penetrance. Further study suggests these differences to be specific to subrolandic white matter regions somatotopically related to clinical phenotype. Clinical severity was correlated to the degree of microstructural change. These findings suggest a mechanism for the penetrance and clinical variability observed in dystonia and may represent a novel therapeutic target for patients with refractory limb symptoms.
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Affiliation(s)
- Renata P Lerner
- Center for Neurosciences, The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY, 11030, USA
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32
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Prell T, Peschel T, Köhler B, Bokemeyer MH, Dengler R, Günther A, Grosskreutz J. Structural brain abnormalities in cervical dystonia. BMC Neurosci 2013; 14:123. [PMID: 24131497 PMCID: PMC3852757 DOI: 10.1186/1471-2202-14-123] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 10/09/2013] [Indexed: 12/13/2022] Open
Abstract
Background Idiopathic cervical dystonia is characterized by involuntary spasms, tremors or jerks. It is not restricted to a disturbance in the basal ganglia system because non-conventional voxel-based MRI morphometry (VBM) and diffusion tensor imaging (DTI) have detected numerous regional changes in the brains of patients. In this study scans of 24 patients with cervical dystonia and 24 age-and sex-matched controls were analysed using VBM, DTI and magnetization transfer imaging (MTI) using a voxel-based approach and a region-of-interest analysis. Results were correlated with UDRS, TWSTRS and disease duration. Results We found structural alterations in the basal ganglia; thalamus; motor cortex; premotor cortex; frontal, temporal and parietal cortices; visual system; cerebellum and brainstem of the patients with dystonia. Conclusions Cervical dystonia is a multisystem disease involving several networks such as the motor, sensory and visual systems.
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Affiliation(s)
- Tino Prell
- Hans-Berger Department of Neurology, Jena University Hospital, Erlanger Allee 101, 07747 Jena, Germany.
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Ramdhani RA, Simonyan K. Primary dystonia: conceptualizing the disorder through a structural brain imaging lens. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2013; 3. [PMID: 23610744 PMCID: PMC3629863 DOI: 10.7916/d8h70dj7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 03/08/2013] [Indexed: 12/14/2022]
Abstract
Background Dystonia is a hyperkinetic movement disorder characterized by involuntary, repetitive twisting movements. The anatomical structures and pathways implicated in its pathogenesis and their relationships to the neurophysiological paradigms of abnormal surround inhibition, maladaptive plasticity, and impaired sensorimotor integration remain unclear. Objective We review the use of high-resolution structural brain imaging using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) techniques for evaluating brain changes in primary torsion dystonia and their relationships to the pathophysiology of this disorder. Methods A PubMed search was conducted to identify relevant literature. Results VBM and DTI studies produced somewhat conflicting results across different forms of primary dystonia and reported increases, decreases, or both in gray matter volume and white matter integrity. However, despite the discrepancies, these studies are consistent in revealing brain abnormalities in dystonia that extend beyond the basal ganglia and involve the sensorimotor cortex and cerebellum. Discussion Although limited to date, structural magnetic resonance imaging (MRI) studies combined with functional brain imaging and neurophysiological modalities begin to establish structural-functional relationships at different levels of the abnormal basal ganglia, cortical, and cerebellar networks and provide clues into the pathophysiological mechanisms that underlie primary dystonia. Cross-disciplinary studies are needed for further investigations of the interplay between structural-functional brain abnormalities and environmental and genetic risk factors in dystonia patients.
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Affiliation(s)
- Ritesh A Ramdhani
- Departments of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States of America
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Hoffland BS, Kassavetis P, Bologna M, Teo JTH, Bhatia KP, Rothwell JC, Edwards MJ, van de Warrenburg BP. Cerebellum-dependent associative learning deficits in primary dystonia are normalized by rTMS and practice. Eur J Neurosci 2013; 38:2166-71. [DOI: 10.1111/ejn.12186] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 02/13/2013] [Indexed: 11/29/2022]
Affiliation(s)
| | - P. Kassavetis
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; UCL; Queen Square; London; WC1N 3BG; UK
| | - M. Bologna
- Neuromed Institute (IRCCS); Pozzilli (IS); Italy
| | - J. T. H. Teo
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; UCL; Queen Square; London; WC1N 3BG; UK
| | - K. P. Bhatia
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; UCL; Queen Square; London; WC1N 3BG; UK
| | - J. C. Rothwell
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; UCL; Queen Square; London; WC1N 3BG; UK
| | - M. J. Edwards
- Sobell Department of Motor Neuroscience and Movement Disorders; UCL Institute of Neurology; UCL; Queen Square; London; WC1N 3BG; UK
| | - B. P. van de Warrenburg
- Department of Neurology; Donders Centre for Neuroscience; Radboud University Nijmegen Medical Centre; Nijmegen; The Netherlands
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Filip P, Lungu OV, Bareš M. Dystonia and the cerebellum: a new field of interest in movement disorders? Clin Neurophysiol 2013; 124:1269-76. [PMID: 23422326 DOI: 10.1016/j.clinph.2013.01.003] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Revised: 01/06/2013] [Accepted: 01/08/2013] [Indexed: 11/17/2022]
Abstract
Although dystonia has traditionally been regarded as a basal ganglia dysfunction, recent provocative evidence has emerged of cerebellar involvement in the pathophysiology of this enigmatic disease. This review synthesizes the data suggesting that the cerebellum plays an important role in dystonia etiology, from neuroanatomical research of complex networks showing that the cerebellum is connected to a wide range of other central nervous system structures involved in movement control to animal models indicating that signs of dystonia are due to cerebellum dysfunction and completely disappear after cerebellectomy, and finally to clinical observations in secondary dystonia patients with various types of cerebellar lesions. We propose that dystonia is a large-scale dysfunction, involving not only cortico-basal ganglia-thalamo-cortical pathways, but the cortico-ponto-cerebello-thalamo-cortical loop as well. Even in the absence of traditional "cerebellar signs" in most dystonia patients, there are more subtle indications of cerebellar dysfunction. It is clear that as long as the cerebellum's role in dystonia genesis remains unexamined, it will be difficult to significantly improve the current standards of dystonia treatment or to provide curative treatment.
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Affiliation(s)
- Pavel Filip
- Central European Institute of Technology, CEITEC MU, Behavioral and Social Neuroscience Research Group, Masaryk University, Brno, Czech Republic
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van der Meer JN, Beukers RJ, van der Salm SMA, Caan MWA, Tijssen MAJ, Nederveen AJ. White matter abnormalities in gene-positive myoclonus-dystonia. Mov Disord 2012; 27:1666-72. [PMID: 23114862 DOI: 10.1002/mds.25128] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 06/14/2012] [Accepted: 07/03/2012] [Indexed: 11/09/2022] Open
Abstract
Myoclonus-dystonia is an autosomal dominantly inherited movement disorder clinically characterized by myoclonic jerks and dystonic movements of the upper body. Functional imaging and structural gray matter imaging studies in M-D suggest defective sensorimotor integration and an association between putaminal volume and severity of dystonia, possibly because of neuronal plasticity. As we expect changes in the connections between the cortical and subcortical regions, we performed a combination of white matter voxel-based morphometry (wVBM) and diffusion tensor imaging (DTI) to detect macro- and microstructural white matter changes, respectively, in DYT-11 mutations carriers (M-D). Sixteen clinically affected DYT-11 mutation carriers and 18 control subjects were scanned with 3-Tesla MRI to compare white matter volume, fractional anisotropy, and mean diffusivity between groups. In DYT11 mutation carriers, increased white matter volume and FA and decreased mean diffusivity were found in the subthalamic area of the brain stem, including the red nucleus. Furthermore, decreased mean diffusivity was found in the subgyral cortical sensorimotor areas. The white matter changes found in the subthalamic area of the brain stem, connecting the cerebellum with the thalamus, are compatible with the hypothesis that abnormal function in M-D involves a network that includes the cerebellum, brain stem, and basal ganglia. Whether these changes are causative or an effect of M-D requires further study.
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Affiliation(s)
- Johan N van der Meer
- Academic Medical Center, University of Amsterdam, Department of Clinical Neurophysiology, Amsterdam, The Netherlands
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McCarthy DM, Gioioso V, Zhang X, Sharma N, Bhide PG. Neurogenesis and neuronal migration in the forebrain of the TorsinA knockout mouse embryo. Dev Neurosci 2012; 34:366-78. [PMID: 23018676 DOI: 10.1159/000342260] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 07/26/2012] [Indexed: 01/07/2023] Open
Abstract
Early-onset generalized torsion dystonia, also known as DYT1 dystonia, is a childhood onset heritable neurological movement disorder involving painful, involuntary muscle contractions, sustained abnormal postures, and repetitive movements. It is caused by a GAG deletion in the Tor1A gene located on chromosome 9. TorsinA, the product of the Tor1A gene, is expressed throughout the brain beginning early in embryonic development. It plays a role in the regulation of nuclear envelope-cytoskeletal interactions, and presumably nuclear translocation. Since nuclear translocation, powered by cytoskeletal traction, is critical for cell proliferation and migration, we examined whether neurogenesis and neuronal migration are affected in Tor1A-/- mouse brain. Our data show that interkinetic nuclear migration and the pattern of migration of newly generated neurons are impaired in the dorsal forebrain of the Tor1A-/- embryo. However, neurogenesis is not altered significantly. The rate of migration of cells from explants of the medial ganglionic eminence is also impaired in the Tor1A-/- embryo. Thus, loss of torsinA results in subtle but significant alterations in cell proliferation and migration in the embryonic forebrain. These subtle developmental changes are consistent with a lack of significant changes in neuronal numbers, neuronal positioning or size of brain regions in DYT1 dystonia patients.
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Affiliation(s)
- Deirdre M McCarthy
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL 32303, USA
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Abstract
Dystonia has generally been considered a basal ganglia (BG) disorder. Early models hypothesized that dystonia occurred as the result of reduced mean discharge rates in the internal segment of the globus pallidus (GPi). Increasing evidence suggests a more systemwide disruption of the basal ganglia thalamic circuit (BGTC) resulting in altered firing patterns, synchronized oscillations, and widened receptive fields. A model of dystonia incorporating these changes within the BGTC is presented in which we postulate that this pathophysiology arises from disruptions within the striatum. Alterations in the cerebellothalamocortical (CBTC) pathway to the development of dystonia may also play a role. However, the contribution of CBTC abnormalities to dystonia remains unclear and may vary with different etiologies of dystonia. Finally, the relevance of established and emerging theories related to the pathophysiology of dystonia is addressed within the context of improving conventional approaches for deep brain stimulation (DBS) treatment strategies.
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Horovitz SG, Ford A, Najee-Ullah MA, Ostuni JL, Hallett M. Anatomical correlates of blepharospasm. Transl Neurodegener 2012; 1:12. [PMID: 23210426 PMCID: PMC3514098 DOI: 10.1186/2047-9158-1-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 06/07/2012] [Indexed: 11/10/2022] Open
Abstract
Background Focal dystonia is a neurological disorder characterized by unwanted muscle spasms. Blepharospasm is a focal dystonia producing an involuntary closure of the eyelid. Its etiology is unknown. Objective To investigate if there are structural changes in the white and grey matter of blepharospasm patients, and if the changes are related to disease features. Methods T1 and diffusion-weighted magnetic resonance imaging scans were collected from 14 female blepharospasm patients and 14 healthy matched controls. Grey matter volumes, fractional anisotropy (FA), and mean diffusivity maps were compared between the groups. Based on grey matter differences within the facial portion of the primary motor cortex, the corticobulbar tract was traced and compared between groups. Results Changes in grey matter in patients included the facial portion of the sensorimotor area and anterior cingulate gyrus. These changes did not correlate with disease duration. Corticobulbar tract volume and peak tract connectivity were decreased in patients compared with controls. There were no significant differences in FA or mean diffusivity between groups. Conclusions Grey matter changes within the primary sensorimotor and the anterior cingulate cortices in blepharospasm patients may help explain involuntary eyelid closure and the abnormal sensations often reported in this condition.
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Affiliation(s)
- Silvina G Horovitz
- Human Motor Control Section, Medical Neurology Branch, National Institute of Neurological Disorders and Stroke, 10 Center Drive, Bdg10/7D37, Bethesda, MD, USA.
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Cheng FB, Wan XH, Feng JC, Ma LY, Hou B, Feng F, Wang L, Yang YM. Subcellular distribution of THAP1 and alterations in the microstructure of brain white matter in DYT6 dystonia. Parkinsonism Relat Disord 2012; 18:978-82. [PMID: 22652465 DOI: 10.1016/j.parkreldis.2012.05.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 03/29/2012] [Accepted: 05/09/2012] [Indexed: 11/17/2022]
Abstract
BACKGROUND Mutations in the THAP1 gene have recently been identified as the cause of DYT6 primary dystonia. However, the changes in THAP1 gene function and in the microstructure of brain white matter have not been well-characterized. METHODS Four different mutations of THAP1 expression (clones F22fs71X, C54F, F25fs53X, and L180S) were transfected into HEK-293T cells. The subcellular distribution of THAP1 in each clone was identified using immunofluorescence microscopy and Western blot. Six patients who harbored these THAP1 mutations underwent diffusion tensor magnetic resonance imaging (DTI) of the brain. The fractional anisotropy (FA) and mean diffusivity (MD) were measured in twenty-four regions of interest (ROI). RESULTS In two truncated mutations (F22fs71X and F25fs53X), the subcellular distribution of THAP1 were both in the cytoplasm and nucleus. However, the subcellular distribution was detected almost in the nucleus in two missense mutations (C54F and L180S). In the DTI maps, the average values of fractional anisotropy (FA), a measure of axonal integrity and coherence, was reduced (p < 0.005) in the subgyral white matter of the sensorimotor cortex of the DYT1 carriers, comparing with controls. CONCLUSIONS Truncated THAP1 mutations (F22fs71X and F25fs53X) can alter the subcellular distributions, while some missense mutation (C54F and L180S) can not. The axonal integrity and coherence in the region of sensorimotor area of the brain was damaged in DYT6 dystonia.
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Affiliation(s)
- Fu Bo Cheng
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, 1# Shuaifuyuan, Wangfujing Street, Beijing, PR China
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Alvarez-Fischer D, Grundmann M, Lu L, Samans B, Fritsch B, Möller JC, Schaefer MKH, Hartmann A, Oertel WH, Bandmann O. Prolonged generalized dystonia after chronic cerebellar application of kainic acid. Brain Res 2012; 1464:82-8. [PMID: 22595488 DOI: 10.1016/j.brainres.2012.05.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 05/01/2012] [Accepted: 05/06/2012] [Indexed: 11/28/2022]
Abstract
Dystonia has traditionally been considered as a basal ganglia disorder, but there is growing evidence that impaired function of the cerebellum may also play a crucial part in the pathogenesis of this disorder. We now demonstrate that chronic application of kainic acid into the cerebellar vermis of rats results in a prolonged and generalized dystonic motor phenotype and provide detailed characterization of this new animal model for dystonia. c-fos expression, as a marker of neuronal activation, was increased not only in the cerebellum itself, but also in the ventro-anterior thalamus, further supporting the assumption of a disturbed neuronal network underlying the pathogenesis of this disorder. Preproenkephalin expression in the striatum was reduced, but prodynorphin expression remained unaltered, suggesting secondary changes in the indirect, but not in the direct basal ganglia pathway in our model system. Hsp70 expression was specifically increased in the Purkinje cell layer and the red nucleus. This new rat model of dystonia may be useful not only for further studies investigating the role of the cerebellum in the pathogenesis of dystonia, but also to assess compounds for their beneficial effect on dystonia in a rodent model of prolonged, generalized dystonia.
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Yokoi F, Dang MT, Yang G, Li J, Doroodchi A, Zhou T, Li Y. Abnormal nuclear envelope in the cerebellar Purkinje cells and impaired motor learning in DYT11 myoclonus-dystonia mouse models. Behav Brain Res 2012; 227:12-20. [PMID: 22040906 PMCID: PMC3242862 DOI: 10.1016/j.bbr.2011.10.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 10/10/2011] [Accepted: 10/16/2011] [Indexed: 11/22/2022]
Abstract
Myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonia. DYT11 M-D is caused by mutations in SGCE which codes for ɛ-sarcoglycan. SGCE is maternally imprinted and paternally expressed. Abnormal nuclear envelope has been reported in mouse models of DYT1 generalized torsion dystonia. However, it is not known whether similar alterations occur in DYT11 M-D. We developed a mouse model of DYT11 M-D using paternally inherited Sgce heterozygous knockout (Sgce KO) mice and reported that they had myoclonus and motor coordination and learning deficits in the beam-walking test. However, the specific brain regions that contribute to these phenotypes have not been identified. Since ɛ-sarcoglycan is highly expressed in the cerebellar Purkinje cells, here we examined the nuclear envelope in these cells using a transmission electron microscope and found that they are abnormal in Sgce KO mice. Our results put DYT11 M-D in a growing family of nuclear envelopathies. To analyze the effect of loss of ɛ-sarcoglycan function in the cerebellar Purkinje cells, we produced paternally inherited cerebellar Purkinje cell-specific Sgce conditional knockout (Sgce pKO) mice. Sgce pKO mice showed motor learning deficits, while they did not show abnormal nuclear envelope in the cerebellar Purkinje cells, robust motor deficits, or myoclonus. The results suggest that ɛ-sarcoglycan in the cerebellar Purkinje cells contributes to the motor learning, while loss of ɛ-sarcoglycan in other brain regions may contribute to nuclear envelope abnormality, myoclonus and motor coordination deficits.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Mai T. Dang
- Department of Neurology, Hospital of University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Guang Yang
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - JinDong Li
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Atbin Doroodchi
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Tong Zhou
- Clinical Immunology and Rheumatology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yuqing Li
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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Functional brain networks and abnormal connectivity in the movement disorders. Neuroimage 2011; 62:2261-70. [PMID: 22206967 DOI: 10.1016/j.neuroimage.2011.12.021] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 11/09/2011] [Accepted: 12/13/2011] [Indexed: 01/18/2023] Open
Abstract
Clinical manifestations of movement disorders, such as Parkinson's disease (PD) and dystonia, arise from neurophysiological changes within the cortico-striato-pallidothalamocortical (CSPTC) and cerebello-thalamo-cortical (CbTC) circuits. Neuroimaging techniques that probe connectivity within these circuits can be used to understand how these disorders develop as well as identify potential targets for medical and surgical therapies. Indeed, network analysis of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has identified abnormal metabolic networks associated with the cardinal motor symptoms of PD, such as akinesia and tremor, as well as PD-related cognitive dysfunction. More recent task-based and resting state functional magnetic resonance imaging studies have reproduced several of the altered connectivity patterns identified in these abnormal PD-related networks. A similar network analysis approach in dystonia revealed abnormal disease related metabolic patterns in both manifesting and non-manifesting carriers of dystonia mutations. Other multimodal imaging approaches using magnetic resonance diffusion tensor imaging in patients with primary genetic dystonia suggest abnormal connectivity within the CbTC circuits mediate the clinical manifestations of this inherited neurodevelopmental disorder. Ongoing developments in functional imaging and future studies in early patients are likely to enhance our understanding of these movement disorders and guide novel targets for future therapies.
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Yokoi F, Dang MT, Zhou T, Li Y. Abnormal nuclear envelopes in the striatum and motor deficits in DYT11 myoclonus-dystonia mouse models. Hum Mol Genet 2011; 21:916-25. [PMID: 22080833 DOI: 10.1093/hmg/ddr528] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
DYT11 myoclonus-dystonia (M-D) is a movement disorder characterized by myoclonic jerks with dystonic symptoms and caused by mutations in paternally expressed SGCE, which codes for ε-sarcoglycan. Paternally inherited Sgce heterozygous knock-out (KO) mice exhibit motor deficits and spontaneous myoclonus. Abnormal nuclear envelopes have been reported in cellular and mouse models of early-onset DYT1 generalized torsion dystonia; however, the relationship between the abnormal nuclear envelopes and motor symptoms are not clear. Furthermore, it is not known whether abnormal nuclear envelope exists in non-DYT1 dystonia. In the present study, abnormal nuclear envelopes in the striatal medium spiny neurons (MSNs) were found in Sgce KO mice. To analyze whether the loss of ε-sarcoglycan in the striatum alone causes abnormal nuclear envelopes, motor deficits or myoclonus, we produced paternally inherited striatum-specific Sgce conditional KO (Sgce sKO) mice and analyzed their phenotypes. Sgce sKO mice exhibited motor deficits in both beam-walking and accelerated rotarod tests, while they did not exhibit abnormal nuclear envelopes, alteration in locomotion, or myoclonus. The results suggest that the loss of ε-sarcoglycan in the striatum contributes to motor deficits, while it alone does not produce abnormal nuclear envelopes or myoclonus. Development of therapies targeting the striatum to compensate for the loss of ε-sarcoglycan function may rescue the motor deficits in DYT11 M-D patients.
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Affiliation(s)
- Fumiaki Yokoi
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL 32610-0236, USA
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Sadnicka A, Hoffland BS, Bhatia KP, van de Warrenburg BP, Edwards MJ. The cerebellum in dystonia - help or hindrance? Clin Neurophysiol 2011; 123:65-70. [PMID: 22078259 DOI: 10.1016/j.clinph.2011.04.027] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 03/21/2011] [Accepted: 04/05/2011] [Indexed: 10/15/2022]
Abstract
Dystonia has historically been considered a disorder of the basal ganglia. This review aims to critically examine the evidence for a role of the cerebellum in the pathophysiology of dystonia. We compare and attempt to link the information available from both clinical and experimental studies; work detailing cerebellar connectivity in primates; data that suggests a role for the cerebellum in the genesis of dystonia in murine models; clinical observation in humans with structural lesions and heredodegenerative disorders of the cerebellum; and imaging studies of patients with dystonia. The typical electrophysiological findings in dystonia are the converse to those found in cerebellar lesions. However, certain subtypes of dystonia mirror cerebellar patterns of increased cortical inhibition. Furthermore, altered cerebellar function can be demonstrated in adult onset focal dystonia with impaired cerebellar inhibition of motor cortex and abnormal eyeblink classical conditioning. We propose that abnormal, likely compensatory activity of the cerebellum is an important factor within pathophysiological models of dystonia. Work in this exciting area has only just begun but it is likely that the cerebellum will have a key place within future models of dystonia.
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Affiliation(s)
- A Sadnicka
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute for Neurology, Queen Square, London WC1N 3BG, UK
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Abstract
In the last 25 years there have been enormous advances in brain imaging. In addition to utility in diagnosis, these have led to novel insights into the pathogenesis of basal ganglia disease and the role of dopamine and the basal ganglia in normal health. The authors review highlights of this work, with a focus on advances in Parkinson's disease, the dystonias, Huntington's disease, and the role of dopamine in cognition and reward signaling. Emerging areas for future development include studies of functional connectivity, the analysis of default mode networks, studies of novel neurochemical pathways, methods to study disease pathogenesis, and the application of imaging techniques to investigate animal models of disease.
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Affiliation(s)
- A Jon Stoessl
- Pacific Parkinson's Research Centre, University of British Columbia & Vancouver Coastal Health, Vancouver, British Columbia, Canada.
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Abstract
The last 25 years have seen remarkable advances in our understanding of the genetic etiologies of dystonia, new approaches into dissecting underlying pathophysiology, and independent progress in identifying effective treatments. In this review we highlight some of these advances, especially the genetic findings that have taken us from phenomenological to molecular-based diagnoses. Twenty DYT loci have been designated and 10 genes identified, all based on linkage analyses in families. Hand in hand with these genetic findings, neurophysiological and imaging techniques have been employed that have helped illuminate the similarities and differences among the various etiological dystonia subtypes. This knowledge is just beginning to yield new approaches to treatment including those based on DYT1 animal models. Despite the lag in identifying genetically based therapies, effective treatments, including impressive benefits from deep brain stimulation and botulinum toxin chemodenervation, have marked the last 25 years. The challenge ahead includes continued advancement into understanding dystonia's many underlying causes and associated pathology and using this knowledge to advance treatment including preventing genetic disease expression.
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Affiliation(s)
- Laurie J Ozelius
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, New York, New York, USA
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Uluğ AM, Vo A, Argyelan M, Tanabe L, Schiffer WK, Dewey S, Dauer WT, Eidelberg D. Cerebellothalamocortical pathway abnormalities in torsinA DYT1 knock-in mice. Proc Natl Acad Sci U S A 2011; 108:6638-43. [PMID: 21464304 PMCID: PMC3081027 DOI: 10.1073/pnas.1016445108] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The factors that determine symptom penetrance in inherited disease are poorly understood. Increasingly, magnetic resonance diffusion tensor imaging (DTI) and PET are used to separate alterations in brain structure and function that are linked to disease symptomatology from those linked to gene carrier status. One example is DYT1 dystonia, a dominantly inherited movement disorder characterized by sustained muscle contractions, postures, and/or involuntary movements. This form of dystonia is caused by a 3-bp deletion (i.e., ΔE) in the TOR1A gene that encodes torsinA. Carriers of the DYT1 dystonia mutation, even if clinically nonpenetrant, exhibit abnormalities in cerebellothalamocortical (CbTC) motor pathways. However, observations in human gene carriers may be confounded by variability in genetic background and age. To address this problem, we implemented a unique multimodal imaging strategy in a congenic line of DYT1 mutant mice that contain the ΔE mutation in the endogenous mouse torsinA allele (i.e., DYT1 knock-in). Heterozygous knock-in mice and littermate controls underwent microPET followed by ex vivo high-field DTI and tractographic analysis. Mutant mice, which do not display abnormal movements, exhibited significant CbTC tract changes as well as abnormalities in brainstem regions linking cerebellar and basal ganglia motor circuits highly similar to those identified in human nonmanifesting gene carriers. Moreover, metabolic activity in the sensorimotor cortex of these animals was closely correlated with individual measures of CbTC pathway integrity. These findings further link a selective brain circuit abnormality to gene carrier status and demonstrate that DYT1 mutant torsinA has similar effects in mice and humans.
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Affiliation(s)
- Aziz M. Uluğ
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY 10461; and
| | - An Vo
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
| | - Miklos Argyelan
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
| | - Lauren Tanabe
- Departments of Neurology and Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Wynne K. Schiffer
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
| | - Stephen Dewey
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
| | - William T. Dauer
- Departments of Neurology and Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - David Eidelberg
- Center for Neurosciences, The Feinstein Institute for Medical Research, Manhasset, NY 11030
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Fiorio M, Weise D, Önal-Hartmann C, Zeller D, Tinazzi M, Classen J. Impairment of the rubber hand illusion in focal hand dystonia. Brain 2011; 134:1428-37. [PMID: 21378099 DOI: 10.1093/brain/awr026] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Patients with dystonia display a number of disturbances in the cognitive processing of movements, such as movement simulation and prediction, but whether these deficits point to a deeper rooted disturbance of perceptual bodily representations remains unknown. A useful way to investigate the sense of body ownership is the rubber hand paradigm, in which an illusion of ownership is established by synchronous stroking of the participants' real unseen hand and a visible fake hand, whereas similar asynchronous stroking does not bring about the illusion. This paradigm allows testing of both the subjective experience of feeling ownership over the rubber hand and the proprioceptive relocation of the real unseen hand towards the viewed rubber hand. Previous studies have mapped these different aspects onto two anatomically distinct neuronal substrates, with the ventral premotor cortex processing the illusory feeling of ownership and the inferior parietal lobule and cerebellum processing proprioceptive drift. We applied the rubber hand illusion task to healthy subjects and to patients affected by two different types of focal dystonia-one specifically affecting the hand (focal hand dystonia) and one not affecting the hand (torticollis and blepharospasm). Results showed that in patients with focal hand dystonia, the proprioceptive drift was selectively disrupted on the dystonic hand while the subjective experience of the illusion was retained. In the non-dystonic hand and in the other two groups (non-hand dystonia and healthy subjects), the rubber hand illusion resembled the typical pattern with synchronous stroking eliciting the illusion. These findings provide support for the contention that the mechanisms underlying the presence of the illusory feeling of ownership and the proprioceptive drift are different. Selective impairment of the limb recalibration on the dystonic hand points to underlying deficits in integrating the visual-tactile input with the proprioceptive information in order to update the current body position and may support a model linking dystonia to dysfunctions in a network comprising the inferior parietal cortex and the cerebellum.
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Affiliation(s)
- Mirta Fiorio
- Human Cortical Physiology and Motor Control Laboratory, Department of Neurology, University of Wuerzburg, D-97080 Wuerzburg, Germany.
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Neychev VK, Gross RE, Lehéricy S, Hess EJ, Jinnah HA. The functional neuroanatomy of dystonia. Neurobiol Dis 2011; 42:185-201. [PMID: 21303695 DOI: 10.1016/j.nbd.2011.01.026] [Citation(s) in RCA: 320] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 01/08/2011] [Accepted: 01/28/2011] [Indexed: 10/18/2022] Open
Abstract
Dystonia is a neurological disorder characterized by involuntary twisting movements and postures. There are many different clinical manifestations, and many different causes. The neuroanatomical substrates for dystonia are only partly understood. Although the traditional view localizes dystonia to basal ganglia circuits, there is increasing recognition that this view is inadequate for accommodating a substantial portion of available clinical and experimental evidence. A model in which several brain regions play a role in a network better accommodates the evidence. This network model accommodates neuropathological and neuroimaging evidence that dystonia may be associated with abnormalities in multiple different brain regions. It also accommodates animal studies showing that dystonic movements arise with manipulations of different brain regions. It is consistent with neurophysiological evidence suggesting defects in neural inhibitory processes, sensorimotor integration, and maladaptive plasticity. Finally, it may explain neurosurgical experience showing that targeting the basal ganglia is effective only for certain subpopulations of dystonia. Most importantly, the network model provides many new and testable hypotheses with direct relevance for new treatment strategies that go beyond the basal ganglia. This article is part of a Special Issue entitled "Advances in dystonia".
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