1
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Nakamura R, Iwai T, Takanezawa Y, Shirahata T, Konishi N, Ohshiro Y, Uraguchi S, Tanabe M, Kobayashi Y, Sakamoto K, Nakahara T, Yamamoto M, Kiyono M. Oleanolic acid-3-glucoside, a synthetic oleanane-type saponin, ameliorates methylmercury-induced dysfunction of synaptic transmission in mice. Toxicology 2024; 506:153867. [PMID: 38906242 DOI: 10.1016/j.tox.2024.153867] [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: 04/11/2024] [Revised: 06/07/2024] [Accepted: 06/17/2024] [Indexed: 06/23/2024]
Abstract
Methylmercury (MeHg) is widely distributed in nature and is known to cause neurotoxic effects. This study aimed to examine the anti-MeHg activity of oleanolic acid-3-glucoside (OA3Glu), a synthetic oleanane-type saponin derivative, by evaluating its effects on motor function, pathology, and electrophysiological properties in a mouse model of MeHg poisoning. Mice were orally administered 2 or 4 mg·kg-1·d-1 MeHg with or without 100 µg·kg-1·d-1 OA3Glu 5x/week for four weeks. Motor function was evaluated using beam-walking and dynamic weight-bearing (DWB) tests. High-dose MeHg exposure significantly increased the frequency of stepping off the hind leg while crossing the beam in the beam-walking test, and increased weight on forelegs when moving freely in the DWB test. OA3Glu treatment alleviated motor abnormality caused by high-dose MeHg exposure in both motor function tests. Additionally, OA3Glu treatment reduced the number of contracted Purkinje cells frequently observed in the cerebellum of MeHg-treated groups, although cerebrum histology was similar in all experimental groups. The synaptic potential amplitude in the cerebellum decreased as MeHg exposure increased, which was restored by OA3Glu treatment. Even in the cerebrum, where the effects of MeHg were not observed, the amplitude of the field potential was suppressed with increasing MeHg exposure but was restored with OA3Glu treatment. Taken together, the study findings suggest that OA3Glu improves neurotransmission and movement disorders associated with MeHg exposure via protection of Purkinje cells in the cerebellum while ameliorating pre/post-synaptic deficits in the cerebral cortex in which no changes were observed at the tissue level, potentially providing a treatment to mitigate MeHg toxicity.
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Affiliation(s)
- Ryosuke Nakamura
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Takashi Iwai
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Yasukazu Takanezawa
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Tatsuya Shirahata
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Naruki Konishi
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Yuka Ohshiro
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Shimpei Uraguchi
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Mitsuo Tanabe
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Yoshinori Kobayashi
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Kenji Sakamoto
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan; Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Tsutomu Nakahara
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Megumi Yamamoto
- Department of Environment and Public Health, National Institute for Minamata Disease, 4058-18, Hama, Minamata, Kumamoto 867-0008, Japan
| | - Masako Kiyono
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan.
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2
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Piotrowski D, Clemensson EKH, Nguyen HP, Mark MD. Phenotypic analysis of ataxia in spinocerebellar ataxia type 6 mice using DeepLabCut. Sci Rep 2024; 14:8571. [PMID: 38609436 PMCID: PMC11014858 DOI: 10.1038/s41598-024-59187-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/08/2024] [Indexed: 04/14/2024] Open
Abstract
This study emphasizes the benefits of open-source software such as DeepLabCut (DLC) and R to automate, customize and enhance data analysis of motor behavior. We recorded 2 different spinocerebellar ataxia type 6 mouse models while performing the classic beamwalk test, tracked multiple body parts using the markerless pose-estimation software DLC and analyzed the tracked data using self-written scripts in the programming language R. The beamwalk analysis script (BAS) counts and classifies minor and major hindpaw slips with an 83% accuracy compared to manual scoring. Nose, belly and tail positions relative to the beam, as well as the angle at the tail base relative to the nose and tail tip were determined to characterize motor deficits in greater detail. Our results found distinct ataxic abnormalities such as an increase in major left hindpaw slips and a lower belly and tail position in both SCA6 ataxic mouse models compared to control mice at 18 months of age. Furthermore, a more detailed analysis of various body parts relative to the beam revealed an overall lower body position in the SCA684Q compared to the CT-longQ27PC mouse line at 18 months of age, indicating a more severe ataxic deficit in the SCA684Q group.
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Affiliation(s)
- Dennis Piotrowski
- Behavioral Neuroscience, Faculty for Biology and Biotechnology, Ruhr-University Bochum, ND7/32, Universitätsstr. 150, 44780, Bochum, Germany
| | - Erik K H Clemensson
- Department of Human Genetics, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Huu Phuc Nguyen
- Department of Human Genetics, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Melanie D Mark
- Behavioral Neuroscience, Faculty for Biology and Biotechnology, Ruhr-University Bochum, ND7/32, Universitätsstr. 150, 44780, Bochum, Germany.
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3
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Anderson R, Das MR, Chang Y, Farenhem K, Schmitz CO, Jain A. CAG repeat expansions create splicing acceptor sites and produce aberrant repeat-containing RNAs. Mol Cell 2024; 84:702-714.e10. [PMID: 38295802 PMCID: PMC10923110 DOI: 10.1016/j.molcel.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Revised: 11/07/2023] [Accepted: 01/08/2024] [Indexed: 02/04/2024]
Abstract
Expansions of CAG trinucleotide repeats cause several rare neurodegenerative diseases. The disease-causing repeats are translated in multiple reading frames and without an identifiable initiation codon. The molecular mechanism of this repeat-associated non-AUG (RAN) translation is not known. We find that expanded CAG repeats create new splice acceptor sites. Splicing of proximal donors to the repeats produces unexpected repeat-containing transcripts. Upon splicing, depending on the sequences surrounding the donor, CAG repeats may become embedded in AUG-initiated open reading frames. Canonical AUG-initiated translation of these aberrant RNAs may account for proteins that have been attributed to RAN translation. Disruption of the relevant splice donors or the in-frame AUG initiation codons is sufficient to abrogate RAN translation. Our findings provide a molecular explanation for the abnormal translation products observed in CAG trinucleotide repeat expansion disorders and add to the repertoire of mechanisms by which repeat expansion mutations disrupt cellular functions.
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Affiliation(s)
- Rachel Anderson
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Michael R Das
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Yeonji Chang
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
| | - Kelsey Farenhem
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Cameron O Schmitz
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Ankur Jain
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA.
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4
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Wang D, Honda S, Shin MK, Watase K, Mizusawa H, Ishikawa K, Shimizu S. Subcellular localization and ER-mediated cytotoxic function of α1A and α1ACT in spinocerebellar ataxia type 6. Biochem Biophys Res Commun 2024; 695:149481. [PMID: 38211534 DOI: 10.1016/j.bbrc.2024.149481] [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: 12/20/2023] [Accepted: 01/04/2024] [Indexed: 01/13/2024]
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a polyglutamine (polyQ) disease, which is caused by the elongation of CAG repeats encoding polyQ in the CACNA1A gene. The CACNA1A gene encodes two proteins, namely, α1A (a subunit of the plasma membrane calcium channel), which is translated in its entire length, and α1ACT, which is translated from the second cistron, and both proteins have a polyQ tract. The α1A-polyQ and α1ACT-polyQ proteins with an elongated polyQ stretch have been reported to form aggregates in cells and induce neuronal cell death, but the subcellular localization of these proteins and their cytotoxic properties remain unclear. In this study, we first analyzed SCA6 model mice and found that α1A-polyQlong localized mainly to the Golgi apparatus, whereas a portion of α1ACT-polyQlong localized to the nucleus. Analysis using Neuro2a cells also showed similar subcellular localizations of these proteins, and a proportion of both proteins localized to the endoplasmic reticulum (ER). Cytotoxic studies demonstrated that both proteins induce both the ER stress response and apoptosis, indicating that they are able to induce ER stress-induced apoptosis.
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Affiliation(s)
- Di Wang
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan; Department of Personalized Genomic Medicine for Health, Graduate School of Medicine, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Shinya Honda
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Min Kyoung Shin
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kei Watase
- Center for Brain Integration Research, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Hidehiro Mizusawa
- Center for Brain Integration Research, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan
| | - Kinya Ishikawa
- Department of Personalized Genomic Medicine for Health, Graduate School of Medicine, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
| | - Shigeomi Shimizu
- Department of Pathological Cell Biology, Medical Research Institute, Tokyo Medical and Dental University (TMDU), 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
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5
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Leung TCS, Fields E, Rana N, Shen RYL, Bernstein AE, Cook AA, Phillips DE, Watt AJ. Mitochondrial damage and impaired mitophagy contribute to disease progression in SCA6. Acta Neuropathol 2024; 147:26. [PMID: 38286873 PMCID: PMC10824820 DOI: 10.1007/s00401-023-02680-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/18/2023] [Accepted: 12/27/2023] [Indexed: 01/31/2024]
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a neurodegenerative disease that manifests in midlife and progressively worsens with age. SCA6 is rare, and many patients are not diagnosed until long after disease onset. Whether disease-causing cellular alterations differ at different disease stages is currently unknown, but it is important to answer this question in order to identify appropriate therapeutic targets across disease duration. We used transcriptomics to identify changes in gene expression at disease onset in a well-established mouse model of SCA6 that recapitulates key disease features. We observed both up- and down-regulated genes with the major down-regulated gene ontology terms suggesting mitochondrial dysfunction. We explored mitochondrial function and structure and observed that changes in mitochondrial structure preceded changes in function, and that mitochondrial function was not significantly altered at disease onset but was impaired later during disease progression. We also detected elevated oxidative stress in cells at the same disease stage. In addition, we observed impairment in mitophagy that exacerbates mitochondrial dysfunction at late disease stages. In post-mortem SCA6 patient cerebellar tissue, we observed metabolic changes that are consistent with mitochondrial impairments, supporting our results from animal models being translatable to human disease. Our study reveals that mitochondrial dysfunction and impaired mitochondrial degradation likely contribute to disease progression in SCA6 and suggests that these could be promising targets for therapeutic interventions in particular for patients diagnosed after disease onset.
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Affiliation(s)
| | - Eviatar Fields
- Department of Biology, McGill University, Montreal, QC, Canada
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Namrata Rana
- Department of Biology, McGill University, Montreal, QC, Canada
| | | | | | - Anna A Cook
- Department of Biology, McGill University, Montreal, QC, Canada
| | | | - Alanna J Watt
- Department of Biology, McGill University, Montreal, QC, Canada.
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6
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Cook AA, Leung TCS, Rice M, Nachman M, Zadigue-Dube É, Watt AJ. Endosomal dysfunction contributes to cerebellar deficits in spinocerebellar ataxia type 6. eLife 2023; 12:RP90510. [PMID: 38084749 PMCID: PMC10715727 DOI: 10.7554/elife.90510] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a rare disease that is characterized by cerebellar dysfunction. Patients have progressive motor coordination impairment, and postmortem brain tissue reveals degeneration of cerebellar Purkinje cells and a reduced level of cerebellar brain-derived neurotrophic factor (BDNF). However, the pathophysiological changes underlying SCA6 are not fully understood. We carried out RNA-sequencing of cerebellar vermis tissue in a mouse model of SCA6, which revealed widespread dysregulation of genes associated with the endo-lysosomal system. Since disruption to endosomes or lysosomes could contribute to cellular deficits, we examined the endo-lysosomal system in SCA6. We identified alterations in multiple endosomal compartments in the Purkinje cells of SCA6 mice. Early endosomes were enlarged, while the size of the late endosome compartment was reduced. We also found evidence for impaired trafficking of cargo to the lysosomes. As the proper functioning of the endo-lysosomal system is crucial for the sorting and trafficking of signaling molecules, we wondered whether these changes could contribute to previously identified deficits in signaling by BDNF and its receptor tropomyosin kinase B (TrkB) in SCA6. Indeed, we found that the enlarged early endosomes in SCA6 mice accumulated both BDNF and TrkB. Furthermore, TrkB recycling to the cell membrane in recycling endosomes was reduced, and the late endosome transport of BDNF for degradation was impaired. Therefore, mis-trafficking due to aberrant endo-lysosomal transport and function could contribute to SCA6 pathophysiology through alterations to BDNF-TrkB signaling, as well as mishandling of other signaling molecules. Deficits in early endosomes and BDNF localization were rescued by chronic administration of a TrkB agonist, 7,8-dihydroxyflavone, that we have previously shown restores motor coordination and cerebellar TrkB expression. The endo-lysosomal system is thus both a novel locus of pathophysiology in SCA6 and a promising therapeutic target.
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Affiliation(s)
- Anna A Cook
- Biology Department, McGill UniversityMontrealCanada
| | | | - Max Rice
- Biology Department, McGill UniversityMontrealCanada
- Department of Biological Sciences, Columbia UniversityNew YorkUnited States
| | - Maya Nachman
- Biology Department, McGill UniversityMontrealCanada
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7
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van der Heijden ME, Sillitoe RV. Cerebellar dysfunction in rodent models with dystonia, tremor, and ataxia. DYSTONIA 2023; 2:11515. [PMID: 38105800 PMCID: PMC10722573 DOI: 10.3389/dyst.2023.11515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Dystonia is a movement disorder characterized by involuntary co- or over-contractions of the muscles, which results in abnormal postures and movements. These symptoms arise from the pathophysiology of a brain-wide dystonia network. There is mounting evidence suggesting that the cerebellum is a central node in this network. For example, manipulations that target the cerebellum cause dystonic symptoms in mice, and cerebellar neuromodulation reduces these symptoms. Although numerous findings provide insight into dystonia pathophysiology, they also raise further questions. Namely, how does cerebellar pathophysiology cause the diverse motor abnormalities in dystonia, tremor, and ataxia? Here, we describe recent work in rodents showing that distinct cerebellar circuit abnormalities could define different disorders and we discuss potential mechanisms that determine the behavioral presentation of cerebellar diseases.
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Affiliation(s)
- Meike E. van der Heijden
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, United States
| | - Roy V. Sillitoe
- Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX, United States
- Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX, United States
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX, United States
- Development, Disease Models & Therapeutics Graduate Program, Baylor College of Medicine, Houston, TX, United States
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8
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Anderson R, Das M, Chang Y, Farenhem K, Jain A. CAG repeat expansions create splicing acceptor sites and produce aberrant repeat-containing RNAs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.16.562581. [PMID: 37904984 PMCID: PMC10614865 DOI: 10.1101/2023.10.16.562581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Expansions of CAG trinucleotide repeats cause several rare neurodegenerative diseases. The disease-causing repeats are translated in multiple reading frames, without an identifiable initiation codon. The molecular mechanism of this repeat-associated non-AUG (RAN) translation is not known. We find that expanded CAG repeats create new splice acceptor sites. Splicing of proximal donors to the repeats produces unexpected repeat-containing transcripts. Upon splicing, depending on the sequences surrounding the donor, CAG repeats may become embedded in AUG-initiated open reading frames. Canonical AUG-initiated translation of these aberrant RNAs accounts for proteins that are attributed to RAN translation. Disruption of the relevant splice donors or the in-frame AUG initiation codons is sufficient to abrogate RAN translation. Our findings provide a molecular explanation for the abnormal translation products observed in CAG trinucleotide repeat expansion disorders and add to the repertoire of mechanisms by which repeat expansion mutations disrupt cellular functions.
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Affiliation(s)
- Rachel Anderson
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Michael Das
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Yeonji Chang
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
| | - Kelsey Farenhem
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
| | - Ankur Jain
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
- Department of Biology, Massachusetts Institute of Technology, 31 Ames Street, Cambridge, MA 02139, USA
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9
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Gosalia H, Karsan N, Goadsby PJ. Genetic Mechanisms of Migraine: Insights from Monogenic Migraine Mutations. Int J Mol Sci 2023; 24:12697. [PMID: 37628876 PMCID: PMC10454024 DOI: 10.3390/ijms241612697] [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: 07/06/2023] [Revised: 08/01/2023] [Accepted: 08/06/2023] [Indexed: 08/27/2023] Open
Abstract
Migraine is a disabling neurological disorder burdening patients globally. Through the increasing development of preclinical and clinical experimental migraine models, advancing appreciation of the extended clinical phenotype, and functional neuroimaging studies, we can further our understanding of the neurobiological basis of this highly disabling condition. Despite increasing understanding of the molecular and chemical architecture of migraine mechanisms, many areas require further investigation. Research over the last three decades has suggested that migraine has a strong genetic basis, based on the positive family history in most patients, and this has steered exploration into possibly implicated genes. In recent times, human genome-wide association studies and rodent genetic migraine models have facilitated our understanding, but most migraine seems polygenic, with the monogenic migraine mutations being considerably rarer, so further large-scale studies are required to elucidate fully the genetic underpinnings of migraine and the translation of these to clinical practice. The monogenic migraine mutations cause severe aura phenotypes, amongst other symptoms, and offer valuable insights into the biology of aura and the relationship between migraine and other conditions, such as vascular disease and sleep disorders. This review will provide an outlook of what is known about some monogenic migraine mutations, including familial hemiplegic migraine, familial advanced sleep-phase syndrome, and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.
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Affiliation(s)
- Helin Gosalia
- Headache Group, The Wolfson Sensory, Pain and Rehabilitation Centre, NIHR King’s Clinical Research Facility, & SLaM Biomedical Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (H.G.); (N.K.)
| | - Nazia Karsan
- Headache Group, The Wolfson Sensory, Pain and Rehabilitation Centre, NIHR King’s Clinical Research Facility, & SLaM Biomedical Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (H.G.); (N.K.)
| | - Peter J. Goadsby
- Headache Group, The Wolfson Sensory, Pain and Rehabilitation Centre, NIHR King’s Clinical Research Facility, & SLaM Biomedical Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (H.G.); (N.K.)
- Department of Neurology, University of California, Los Angeles, CA 90095, USA
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10
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Huang H, Shakkottai VG. Targeting Ion Channels and Purkinje Neuron Intrinsic Membrane Excitability as a Therapeutic Strategy for Cerebellar Ataxia. Life (Basel) 2023; 13:1350. [PMID: 37374132 DOI: 10.3390/life13061350] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/03/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
In degenerative neurological disorders such as Parkinson's disease, a convergence of widely varying insults results in a loss of dopaminergic neurons and, thus, the motor symptoms of the disease. Dopamine replacement therapy with agents such as levodopa is a mainstay of therapy. Cerebellar ataxias, a heterogeneous group of currently untreatable conditions, have not been identified to have a shared physiology that is a target of therapy. In this review, we propose that perturbations in cerebellar Purkinje neuron intrinsic membrane excitability, a result of ion channel dysregulation, is a common pathophysiologic mechanism that drives motor impairment and vulnerability to degeneration in cerebellar ataxias of widely differing genetic etiologies. We further propose that treatments aimed at restoring Purkinje neuron intrinsic membrane excitability have the potential to be a shared therapy in cerebellar ataxia akin to levodopa for Parkinson's disease.
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Affiliation(s)
- Haoran Huang
- Medical Scientist Training Program, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Vikram G Shakkottai
- Department of Neurology, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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11
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Figueroa KP, Anderson CJ, Paul S, Dansithong W, Gandelman M, Scoles DR, Pulst SM. Slc9a6 mutation causes Purkinje cell loss and ataxia in the shaker rat. Hum Mol Genet 2023; 32:1647-1659. [PMID: 36621975 PMCID: PMC10162436 DOI: 10.1093/hmg/ddad004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 12/29/2022] [Accepted: 01/05/2023] [Indexed: 01/10/2023] Open
Abstract
The shaker rat carries a naturally occurring mutation leading to progressive ataxia characterized by Purkinje cell (PC) loss. We previously reported on fine-mapping the shaker locus to the long arm of the rat X chromosome. In this work, we sought to identify the mutated gene underlying the shaker phenotype and confirm its identity by functional complementation. We fine-mapped the candidate region and analyzed cerebellar transcriptomes, identifying a XM_217630.9 (Slc9a6):c.[191_195delinsA] variant in the Slc9a6 gene that segregated with disease. We generated an adeno-associated virus (AAV) targeting Slc9a6 expression to PCs using the mouse L7-6 (L7) promoter. We administered the AAV prior to the onset of PC degeneration through intracerebroventricular injection and found that it reduced the shaker motor, molecular and cellular phenotypes. Therefore, Slc9a6 is mutated in shaker and AAV-based gene therapy may be a viable therapeutic strategy for Christianson syndrome, also caused by Slc9a6 mutation.
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Affiliation(s)
- Karla P Figueroa
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Collin J Anderson
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
- School of Medical Sciences, University of Sydney, Camperdown NSW 2006, Australia
- School of Biomedical Engineering University of Sydney, Darlington NSW 2008, Australia
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Mandi Gandelman
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Daniel R Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84132, USA
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12
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Hamanaka K, Yamauchi D, Koshimizu E, Watase K, Mogushi K, Ishikawa K, Mizusawa H, Tsuchida N, Uchiyama Y, Fujita A, Misawa K, Mizuguchi T, Miyatake S, Matsumoto N. Genome-wide identification of tandem repeats associated with splicing variation across 49 tissues in humans. Genome Res 2023; 33:435-447. [PMID: 37307504 PMCID: PMC10078293 DOI: 10.1101/gr.277335.122] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Accepted: 02/22/2023] [Indexed: 03/29/2023]
Abstract
Tandem repeats (TRs) are one of the largest sources of polymorphism, and their length is associated with gene regulation. Although previous studies reported several tandem repeats regulating gene splicing in cis (spl-TRs), no large-scale study has been conducted. In this study, we established a genome-wide catalog of 9537 spl-TRs with a total of 58,290 significant TR-splicing associations across 49 tissues (false discovery rate 5%) by using Genotype-Tissue expression (GTex) Project data. Regression models explaining splicing variation by using spl-TRs and other flanking variants suggest that at least some of the spl-TRs directly modulate splicing. In our catalog, two spl-TRs are known loci for repeat expansion diseases, spinocerebellar ataxia 6 (SCA6) and 12 (SCA12). Splicing alterations by these spl-TRs were compatible with those observed in SCA6 and SCA12. Thus, our comprehensive spl-TR catalog may help elucidate the pathomechanism of genetic diseases.
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Affiliation(s)
- Kohei Hamanaka
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
| | | | - Eriko Koshimizu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
| | - Kei Watase
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Kaoru Mogushi
- Intractable Disease Research Center, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Kinya Ishikawa
- The Center for Personalized Medicine for Healthy Aging, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hidehiro Mizusawa
- Department of Neurology, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8551, Japan
| | - Naomi Tsuchida
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
- Department of Rare Disease Genomics, Yokohama City University Hospital, Yokohama, Kanagawa 236-0004, Japan
| | - Yuri Uchiyama
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
- Department of Rare Disease Genomics, Yokohama City University Hospital, Yokohama, Kanagawa 236-0004, Japan
| | - Atsushi Fujita
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
| | - Kazuharu Misawa
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
| | - Takeshi Mizuguchi
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan
- Clinical Genetics Department, Yokohama City University Hospital, Yokohama, Kanagawa 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa 236-0004, Japan;
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13
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Biswas DD, El Haddad L, Sethi R, Huston ML, Lai E, Abdelbarr MM, Mhandire DZ, ElMallah MK. Neuro-respiratory pathology in spinocerebellar ataxia. J Neurol Sci 2022; 443:120493. [PMID: 36410186 PMCID: PMC9808489 DOI: 10.1016/j.jns.2022.120493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 10/22/2022] [Accepted: 11/09/2022] [Indexed: 11/15/2022]
Abstract
The spinocerebellar ataxias (SCA) are a heterogeneous group of neurodegenerative disorders with an autosomal dominant inheritance. Symptoms include poor coordination and balance, peripheral neuropathy, impaired vision, incontinence, respiratory insufficiency, dysphagia, and dysarthria. Although many patients with SCA have respiratory-related complications, the exact mechanism and extent of this pathology remain unclear. This review aims to provide an update on the recent clinical and preclinical scientific findings on neuropathology causing respiratory insufficiency in SCA.
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Affiliation(s)
- Debolina D Biswas
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Léa El Haddad
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Ronit Sethi
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Meredith L Huston
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Elias Lai
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Mariam M Abdelbarr
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Doreen Z Mhandire
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA
| | - Mai K ElMallah
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Duke University Medical Center, Box 2644, Durham, NC 27710, USA.
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14
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Cook AA, Jayabal S, Sheng J, Fields E, Leung TCS, Quilez S, McNicholas E, Lau L, Huang S, Watt AJ. Activation of TrkB-Akt signaling rescues deficits in a mouse model of SCA6. SCIENCE ADVANCES 2022; 8:eabh3260. [PMID: 36112675 PMCID: PMC9481119 DOI: 10.1126/sciadv.abh3260] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/29/2022] [Indexed: 06/01/2023]
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a neurodegenerative disease resulting in motor coordination deficits and cerebellar pathology. Expression of brain-derived neurotrophic factor (BDNF) is reduced in postmortem tissue from SCA6 patients. Here, we show that levels of cerebellar BDNF and its receptor, tropomyosin receptor kinase B (TrkB), are reduced at an early disease stage in a mouse model of SCA6 (SCA684Q/84Q). One month of exercise elevated cerebellar BDNF expression and improved ataxia and cerebellar Purkinje cell firing rate deficits. A TrkB agonist, 7,8-dihydroxyflavone (7,8-DHF), likewise improved motor coordination and Purkinje cell firing rate and elevated downstream Akt signaling. Prolonged 7,8-DHF administration persistently improved ataxia when treatment commenced near disease onset but was ineffective when treatment was started late. These data suggest that 7,8-DHF, which is orally bioavailable and crosses the blood-brain barrier, is a promising therapeutic for SCA6 and argue for the importance of early intervention for SCA6.
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Affiliation(s)
- Anna A. Cook
- Biology Department, McGill University, Montreal, QC, Canada
| | - Sriram Jayabal
- Biology Department, McGill University, Montreal, QC, Canada
- Integrated Neuroscience Program, McGill University, Montreal, QC, Canada
- Department of Neurobiology, Stanford School of Medicine, Stanford, CA, USA
| | - Jacky Sheng
- Biology Department, McGill University, Montreal, QC, Canada
| | - Eviatar Fields
- Biology Department, McGill University, Montreal, QC, Canada
- Integrated Neuroscience Program, McGill University, Montreal, QC, Canada
| | | | - Sabrina Quilez
- Biology Department, McGill University, Montreal, QC, Canada
| | | | - Lois Lau
- Biology Department, McGill University, Montreal, QC, Canada
| | - Shixia Huang
- Department of Molecular and Cellular Biology, Department of Education, Innovation and Technology, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Alanna J. Watt
- Biology Department, McGill University, Montreal, QC, Canada
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15
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Chang HHV, Cook AA, Watt AJ, Cullen KE. Loss of Flocculus Purkinje Cell Firing Precision Leads to Impaired Gaze Stabilization in a Mouse Model of Spinocerebellar Ataxia Type 6 (SCA6). Cells 2022; 11:cells11172739. [PMID: 36078147 PMCID: PMC9454745 DOI: 10.3390/cells11172739] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/22/2022] [Accepted: 08/26/2022] [Indexed: 11/16/2022] Open
Abstract
Spinocerebellar Ataxia Type 6 (SCA6) is a mid-life onset neurodegenerative disease characterized by progressive ataxia, dysarthria, and eye movement impairment. This autosomal dominant disease is caused by the expansion of a CAG repeat tract in the CACNA1A gene that encodes the α1A subunit of the P/Q type voltage-gated Ca2+ channel. Mouse models of SCA6 demonstrate impaired locomotive function and reduced firing precision of cerebellar Purkinje in the anterior vermis. Here, to further assess deficits in other cerebellar-dependent behaviors, we characterized the oculomotor phenotype of a knock-in mouse model with hyper-expanded polyQ repeats (SCA684Q). We found a reduction in the efficacy of the vestibulo-ocular reflex (VOR) and optokinetic reflex (OKR) in SCA6 mutant mice, without a change in phase, compared to their litter-matched controls. Additionally, VOR motor learning was significantly impaired in SCA684Q mice. Given that the floccular lobe of the cerebellum plays a vital role in the generation of OKR and VOR calibration and motor learning, we investigated the firing behavior and morphology of floccular cerebellar Purkinje cells. Overall, we found a reduction in the firing precision of floccular lobe Purkinje cells but no morphological difference between SCA684Q and wild-type mice. Taken together, our findings establish that gaze stabilization and motor learning are impaired in SCA684Q mice and suggest that altered cerebellar output contributes to these deficits.
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Affiliation(s)
| | - Anna A. Cook
- Department of Biology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Alanna J. Watt
- Department of Biology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Kathleen E. Cullen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21205, USA
- Correspondence:
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16
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Barbé L, Finkbeiner S. Genetic and Epigenetic Interplay Define Disease Onset and Severity in Repeat Diseases. Front Aging Neurosci 2022; 14:750629. [PMID: 35592702 PMCID: PMC9110800 DOI: 10.3389/fnagi.2022.750629] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
Repeat diseases, such as fragile X syndrome, myotonic dystrophy, Friedreich ataxia, Huntington disease, spinocerebellar ataxias, and some forms of amyotrophic lateral sclerosis, are caused by repetitive DNA sequences that are expanded in affected individuals. The age at which an individual begins to experience symptoms, and the severity of disease, are partially determined by the size of the repeat. However, the epigenetic state of the area in and around the repeat also plays an important role in determining the age of disease onset and the rate of disease progression. Many repeat diseases share a common epigenetic pattern of increased methylation at CpG islands near the repeat region. CpG islands are CG-rich sequences that are tightly regulated by methylation and are often found at gene enhancer or insulator elements in the genome. Methylation of CpG islands can inhibit binding of the transcriptional regulator CTCF, resulting in a closed chromatin state and gene down regulation. The downregulation of these genes leads to some disease-specific symptoms. Additionally, a genetic and epigenetic interplay is suggested by an effect of methylation on repeat instability, a hallmark of large repeat expansions that leads to increasing disease severity in successive generations. In this review, we will discuss the common epigenetic patterns shared across repeat diseases, how the genetics and epigenetics interact, and how this could be involved in disease manifestation. We also discuss the currently available stem cell and mouse models, which frequently do not recapitulate epigenetic patterns observed in human disease, and propose alternative strategies to study the role of epigenetics in repeat diseases.
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Affiliation(s)
- Lise Barbé
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, CA, United States
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
- Department of Physiology, University of California, San Francisco, San Francisco, CA, United States
| | - Steve Finkbeiner
- Center for Systems and Therapeutics, Gladstone Institutes, San Francisco, CA, United States
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
- Department of Physiology, University of California, San Francisco, San Francisco, CA, United States
- *Correspondence: Steve Finkbeiner,
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17
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McIntosh CS, Li D, Wilton SD, Aung-Htut MT. Polyglutamine Ataxias: Our Current Molecular Understanding and What the Future Holds for Antisense Therapies. Biomedicines 2021; 9:1499. [PMID: 34829728 PMCID: PMC8615177 DOI: 10.3390/biomedicines9111499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 02/07/2023] Open
Abstract
Polyglutamine (polyQ) ataxias are a heterogenous group of neurological disorders all caused by an expanded CAG trinucleotide repeat located in the coding region of each unique causative gene. To date, polyQ ataxias encompass six disorders: spinocerebellar ataxia types 1, 2, 3, 6, 7, and 17 and account for a larger group of disorders simply known as polyglutamine disorders, which also includes Huntington's disease. These diseases are typically characterised by progressive ataxia, speech and swallowing difficulties, lack of coordination and gait, and are unfortunately fatal in nature, with the exception of SCA6. All the polyQ spinocerebellar ataxias have a hallmark feature of neuronal aggregations and share many common pathogenic mechanisms, such as mitochondrial dysfunction, impaired proteasomal function, and autophagy impairment. Currently, therapeutic options are limited, with no available treatments that slow or halt disease progression. Here, we discuss the common molecular and clinical presentations of polyQ spinocerebellar ataxias. We will also discuss the promising antisense oligonucleotide therapeutics being developed as treatments for these devastating diseases. With recent advancements and therapeutic approvals of various antisense therapies, it is envisioned that some of the studies reviewed may progress into clinical trials and beyond.
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Affiliation(s)
- Craig S. McIntosh
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Dunhui Li
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Steve D. Wilton
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - May T. Aung-Htut
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
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18
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Cendelin J, Cvetanovic M, Gandelman M, Hirai H, Orr HT, Pulst SM, Strupp M, Tichanek F, Tuma J, Manto M. Consensus Paper: Strengths and Weaknesses of Animal Models of Spinocerebellar Ataxias and Their Clinical Implications. THE CEREBELLUM 2021; 21:452-481. [PMID: 34378174 DOI: 10.1007/s12311-021-01311-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/21/2021] [Indexed: 01/02/2023]
Abstract
Spinocerebellar ataxias (SCAs) represent a large group of hereditary degenerative diseases of the nervous system, in particular the cerebellum, and other systems that manifest with a variety of progressive motor, cognitive, and behavioral deficits with the leading symptom of cerebellar ataxia. SCAs often lead to severe impairments of the patient's functioning, quality of life, and life expectancy. For SCAs, there are no proven effective pharmacotherapies that improve the symptoms or substantially delay disease progress, i.e., disease-modifying therapies. To study SCA pathogenesis and potential therapies, animal models have been widely used and are an essential part of pre-clinical research. They mainly include mice, but also other vertebrates and invertebrates. Each animal model has its strengths and weaknesses arising from model animal species, type of genetic manipulation, and similarity to human diseases. The types of murine and non-murine models of SCAs, their contribution to the investigation of SCA pathogenesis, pathological phenotype, and therapeutic approaches including their advantages and disadvantages are reviewed in this paper. There is a consensus among the panel of experts that (1) animal models represent valuable tools to improve our understanding of SCAs and discover and assess novel therapies for this group of neurological disorders characterized by diverse mechanisms and differential degenerative progressions, (2) thorough phenotypic assessment of individual animal models is required for studies addressing therapeutic approaches, (3) comparative studies are needed to bring pre-clinical research closer to clinical trials, and (4) mouse models complement cellular and invertebrate models which remain limited in terms of clinical translation for complex neurological disorders such as SCAs.
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Affiliation(s)
- Jan Cendelin
- Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University, alej Svobody 75, 323 00, Plzen, Czech Republic. .,Laboratory of Neurodegenerative Disorders, Biomedical Center, Faculty of Medicine in Pilsen, Charles University, alej Svobody 75, 323 00, Plzen, Czech Republic.
| | - Marija Cvetanovic
- Department of Neuroscience, Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Mandi Gandelman
- Department of Neurology, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Hirokazu Hirai
- Department of Neurophysiology and Neural Repair, Gunma University Graduate School of Medicine, 3-39-22, Gunma, 371-8511, Japan.,Viral Vector Core, Gunma University Initiative for Advanced Research (GIAR), Gunma, 371-8511, Japan
| | - Harry T Orr
- Department of Laboratory Medicine and Pathology, Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, 175 North Medical Drive East, Salt Lake City, UT, 84132, USA
| | - Michael Strupp
- Department of Neurology and German Center for Vertigo and Balance Disorders, Hospital of the Ludwig-Maximilians University, Munich, Campus Grosshadern, Marchioninistr. 15, 81377, Munich, Germany
| | - Filip Tichanek
- Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University, alej Svobody 75, 323 00, Plzen, Czech Republic.,Laboratory of Neurodegenerative Disorders, Biomedical Center, Faculty of Medicine in Pilsen, Charles University, alej Svobody 75, 323 00, Plzen, Czech Republic
| | - Jan Tuma
- Department of Pathophysiology, Faculty of Medicine in Pilsen, Charles University, alej Svobody 75, 323 00, Plzen, Czech Republic.,The Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, MC 7843, San Antonio, TX, 78229, USA
| | - Mario Manto
- Unité des Ataxies Cérébelleuses, Service de Neurologie, CHU-Charleroi, Charleroi, Belgium.,Service des Neurosciences, Université de Mons, UMons, Mons, Belgium
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19
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Hommersom MP, Buijsen RAM, van Roon-Mom WMC, van de Warrenburg BPC, van Bokhoven H. Human Induced Pluripotent Stem Cell-Based Modelling of Spinocerebellar Ataxias. Stem Cell Rev Rep 2021; 18:441-456. [PMID: 34031815 PMCID: PMC8930896 DOI: 10.1007/s12015-021-10184-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2021] [Indexed: 12/13/2022]
Abstract
Abstract Dominant spinocerebellar ataxias (SCAs) constitute a large group of phenotypically and genetically heterogeneous disorders that mainly present with dysfunction of the cerebellum as their main hallmark. Although animal and cell models have been highly instrumental for our current insight into the underlying disease mechanisms of these neurodegenerative disorders, they do not offer the full human genetic and physiological context. The advent of human induced pluripotent stem cells (hiPSCs) and protocols to differentiate these into essentially every cell type allows us to closely model SCAs in a human context. In this review, we systematically summarize recent findings from studies using hiPSC-based modelling of SCAs, and discuss what knowledge has been gained from these studies. We conclude that hiPSC-based models are a powerful tool for modelling SCAs as they contributed to new mechanistic insights and have the potential to serve the development of genetic therapies. However, the use of standardized methods and multiple clones of isogenic lines are essential to increase validity and reproducibility of the insights gained. Graphical Abstract ![]()
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Affiliation(s)
- Marina P Hommersom
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands
| | - Ronald A M Buijsen
- Department of Human Genetics, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
| | - Willeke M C van Roon-Mom
- Department of Human Genetics, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
| | - Bart P C van de Warrenburg
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands.
| | - Hans van Bokhoven
- Department of Human Genetics, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, The Netherlands. .,Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6500 HB, Nijmegen, Netherlands.
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20
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Nitschke L, Coffin SL, Xhako E, El-Najjar DB, Orengo JP, Alcala E, Dai Y, Wan YW, Liu Z, Orr HT, Zoghbi HY. Modulation of ATXN1 S776 phosphorylation reveals the importance of allele-specific targeting in SCA1. JCI Insight 2021; 6:144955. [PMID: 33554954 PMCID: PMC7934855 DOI: 10.1172/jci.insight.144955] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/23/2020] [Indexed: 11/20/2022] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is an adult-onset neurodegenerative disorder characterized by motor incoordination, mild cognitive decline, respiratory dysfunction, and early lethality. It is caused by the expansion of the polyglutamine (polyQ) tract in Ataxin-1 (ATXN1), which stabilizes the protein, leading to its toxic accumulation in neurons. Previously, we showed that serine 776 (S776) phosphorylation is critical for ATXN1 stability and contributes to its toxicity in cerebellar Purkinje cells. Still, the therapeutic potential of disrupting S776 phosphorylation on noncerebellar SCA1 phenotypes remains unstudied. Here, we report that abolishing S776 phosphorylation specifically on the polyQ-expanded ATXN1 of SCA1-knockin mice reduces ATXN1 throughout the brain and not only rescues the cerebellar motor incoordination but also improves respiratory function and extends survival while not affecting the hippocampal learning and memory deficits. As therapeutic approaches are likely to decrease S776 phosphorylation on polyQ-expanded and WT ATXN1, we further disrupted S776 phosphorylation on both alleles and observed an attenuated rescue, demonstrating a potential protective role of WT allele. This study not only highlights the role of S776 phosphorylation to regulate ATXN1 levels throughout the brain but also suggests distinct brain region–specific disease mechanisms and demonstrates the importance of developing allele-specific therapies for maximal benefits in SCA1.
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Affiliation(s)
- Larissa Nitschke
- Program in Integrative Molecular and Biomedical Sciences and.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
| | - Stephanie L Coffin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Program in Genetics and Genomics
| | - Eder Xhako
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Program in Genetics and Genomics
| | - Dany B El-Najjar
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
| | - James P Orengo
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Department of Neurology, and
| | - Elizabeth Alcala
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
| | - Yanwan Dai
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Ying-Wooi Wan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
| | - Zhandong Liu
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Harry T Orr
- Institute for Translational Neuroscience and Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
| | - Huda Y Zoghbi
- Program in Integrative Molecular and Biomedical Sciences and.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA.,Program in Genetics and Genomics.,Department of Neurology, and.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.,Howard Hughes Medical Institute, Houston, Texas, USA
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21
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Donaldson J, Powell S, Rickards N, Holmans P, Jones L. What is the Pathogenic CAG Expansion Length in Huntington's Disease? J Huntingtons Dis 2021; 10:175-202. [PMID: 33579866 PMCID: PMC7990448 DOI: 10.3233/jhd-200445] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Huntington's disease (HD) (OMIM 143100) is caused by an expanded CAG repeat tract in the HTT gene. The inherited CAG length is known to expand further in somatic and germline cells in HD subjects. Age at onset of the disease is inversely correlated with the inherited CAG length, but is further modulated by a series of genetic modifiers which are most likely to act on the CAG repeat in HTT that permit it to further expand. Longer repeats are more prone to expansions, and this expansion is age dependent and tissue-specific. Given that the inherited tract expands through life and most subjects develop disease in mid-life, this implies that in cells that degenerate, the CAG length is likely to be longer than the inherited length. These findings suggest two thresholds- the inherited CAG length which permits further expansion, and the intracellular pathogenic threshold, above which cells become dysfunctional and die. This two-step mechanism has been previously proposed and modelled mathematically to give an intracellular pathogenic threshold at a tract length of 115 CAG (95% confidence intervals 70- 165 CAG). Empirically, the intracellular pathogenic threshold is difficult to determine. Clues from studies of people and models of HD, and from other diseases caused by expanded repeat tracts, place this threshold between 60- 100 CAG, most likely towards the upper part of that range. We assess this evidence and discuss how the intracellular pathogenic threshold in manifest disease might be better determined. Knowing the cellular pathogenic threshold would be informative for both understanding the mechanism in HD and deploying treatments.
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Affiliation(s)
- Jasmine Donaldson
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, UK
| | - Sophie Powell
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, UK
| | - Nadia Rickards
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, UK
| | - Peter Holmans
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, UK
| | - Lesley Jones
- MRC Centre for Neuropsychiatric Genetics and Genomics, School of Medicine, Cardiff University, Cardiff, UK
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22
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Yeow SQZ, Loh KWZ, Soong TW. Calcium Channel Splice Variants and Their Effects in Brain and Cardiovascular Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1349:67-86. [DOI: 10.1007/978-981-16-4254-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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23
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Commentary to: "The Pathophysiology and Clinical Manifestations of Spinocerebellar Ataxia Type 6" by Rentiya et al., Cerebellum 2020;19(3):459-464). THE CEREBELLUM 2020; 20:484-485. [PMID: 33219436 DOI: 10.1007/s12311-020-01221-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/12/2020] [Indexed: 10/23/2022]
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24
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Zhou J, Brown AM, Lackey EP, Arancillo M, Lin T, Sillitoe RV. Purkinje cell neurotransmission patterns cerebellar basket cells into zonal modules defined by distinct pinceau sizes. eLife 2020; 9:55569. [PMID: 32990595 PMCID: PMC7561353 DOI: 10.7554/elife.55569] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 09/29/2020] [Indexed: 01/05/2023] Open
Abstract
Ramón y Cajal proclaimed the neuron doctrine based on circuit features he exemplified using cerebellar basket cell projections. Basket cells form dense inhibitory plexuses that wrap Purkinje cell somata and terminate as pinceaux at the initial segment of axons. Here, we demonstrate that HCN1, Kv1.1, PSD95 and GAD67 unexpectedly mark patterns of basket cell pinceaux that map onto Purkinje cell functional zones. Using cell-specific genetic tracing with an Ascl1CreERT2 mouse conditional allele, we reveal that basket cell zones comprise different sizes of pinceaux. We tested whether Purkinje cells instruct the assembly of inhibitory projections into zones, as they do for excitatory afferents. Genetically silencing Purkinje cell neurotransmission blocks the formation of sharp Purkinje cell zones and disrupts excitatory axon patterning. The distribution of pinceaux into size-specific zones is eliminated without Purkinje cell GABAergic output. Our data uncover the cellular and molecular diversity of a foundational synapse that revolutionized neuroscience.
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Affiliation(s)
- Joy Zhou
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States
| | - Amanda M Brown
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States
| | - Elizabeth P Lackey
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States
| | - Marife Arancillo
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States
| | - Tao Lin
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, United States.,Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, Houston, United States.,Program in Developmental Biology, Baylor College of Medicine, Houston, United States
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25
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Niewiadomska-Cimicka A, Hache A, Trottier Y. Gene Deregulation and Underlying Mechanisms in Spinocerebellar Ataxias With Polyglutamine Expansion. Front Neurosci 2020; 14:571. [PMID: 32581696 PMCID: PMC7296114 DOI: 10.3389/fnins.2020.00571] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/11/2020] [Indexed: 12/14/2022] Open
Abstract
Polyglutamine spinocerebellar ataxias (polyQ SCAs) include SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17 and constitute a group of adult onset neurodegenerative disorders caused by the expansion of a CAG repeat sequence located within the coding region of specific genes, which translates into polyglutamine tract in the corresponding proteins. PolyQ SCAs are characterized by degeneration of the cerebellum and its associated structures and lead to progressive ataxia and other diverse symptoms. In recent years, gene and epigenetic deregulations have been shown to play a critical role in the pathogenesis of polyQ SCAs. Here, we provide an overview of the functions of wild type and pathogenic polyQ SCA proteins in gene regulation, describe the extent and nature of gene expression changes and their pathological consequences in diseases, and discuss potential avenues to further investigate converging and distinct disease pathways and to develop therapeutic strategies.
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Affiliation(s)
- Anna Niewiadomska-Cimicka
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, Strasbourg, France
| | - Antoine Hache
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, Strasbourg, France
| | - Yvon Trottier
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch, France.,Centre National de la Recherche Scientifique, UMR7104, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, U964, Illkirch, France.,Université de Strasbourg, Strasbourg, France
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26
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Rare CACNA1A mutations leading to congenital ataxia. Pflugers Arch 2020; 472:791-809. [DOI: 10.1007/s00424-020-02396-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 01/03/2023]
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27
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Binda F, Pernaci C, Saxena S. Cerebellar Development and Circuit Maturation: A Common Framework for Spinocerebellar Ataxias. Front Neurosci 2020; 14:293. [PMID: 32300292 PMCID: PMC7145357 DOI: 10.3389/fnins.2020.00293] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 03/13/2020] [Indexed: 01/24/2023] Open
Abstract
Spinocerebellar ataxias (SCAs) affect the cerebellum and its afferent and efferent systems that degenerate during disease progression. In the cerebellum, Purkinje cells (PCs) are the most vulnerable and their prominent loss in the late phase of the pathology is the main characteristic of these neurodegenerative diseases. Despite the constant advancement in the discovery of affected molecules and cellular pathways, a comprehensive description of the events leading to the development of motor impairment and degeneration is still lacking. However, in the last years the possible causal role for altered cerebellar development and neuronal circuit wiring in SCAs has been emerging. Not only wiring and synaptic transmission deficits are a common trait of SCAs, but also preventing the expression of the mutant protein during cerebellar development seems to exert a protective role. By discussing this tight relationship between cerebellar development and SCAs, in this review, we aim to highlight the importance of cerebellar circuitry for the investigation of SCAs.
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Affiliation(s)
- Francesca Binda
- Department of Neurology, Center for Experimental Neurology, University Hospital of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Carla Pernaci
- Department of Neurology, Center for Experimental Neurology, University Hospital of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, Switzerland
| | - Smita Saxena
- Department of Neurology, Center for Experimental Neurology, University Hospital of Bern, Bern, Switzerland.,Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
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28
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Prestori F, Moccia F, D’Angelo E. Disrupted Calcium Signaling in Animal Models of Human Spinocerebellar Ataxia (SCA). Int J Mol Sci 2019; 21:ijms21010216. [PMID: 31892274 PMCID: PMC6981692 DOI: 10.3390/ijms21010216] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/22/2019] [Accepted: 12/24/2019] [Indexed: 12/12/2022] Open
Abstract
Spinocerebellar ataxias (SCAs) constitute a heterogeneous group of more than 40 autosomal-dominant genetic and neurodegenerative diseases characterized by loss of balance and motor coordination due to dysfunction of the cerebellum and its efferent connections. Despite a well-described clinical and pathological phenotype, the molecular and cellular events that underlie neurodegeneration are still poorly undaerstood. Emerging research suggests that mutations in SCA genes cause disruptions in multiple cellular pathways but the characteristic SCA pathogenesis does not begin until calcium signaling pathways are disrupted in cerebellar Purkinje cells. Ca2+ signaling in Purkinje cells is important for normal cellular function as these neurons express a variety of Ca2+ channels, Ca2+-dependent kinases and phosphatases, and Ca2+-binding proteins to tightly maintain Ca2+ homeostasis and regulate physiological Ca2+-dependent processes. Abnormal Ca2+ levels can activate toxic cascades leading to characteristic death of Purkinje cells, cerebellar atrophy, and ataxia that occur in many SCAs. The output of the cerebellar cortex is conveyed to the deep cerebellar nuclei (DCN) by Purkinje cells via inhibitory signals; thus, Purkinje cell dysfunction or degeneration would partially or completely impair the cerebellar output in SCAs. In the absence of the inhibitory signal emanating from Purkinje cells, DCN will become more excitable, thereby affecting the motor areas receiving DCN input and resulting in uncoordinated movements. An outstanding advantage in studying the pathogenesis of SCAs is represented by the availability of a large number of animal models which mimic the phenotype observed in humans. By mainly focusing on mouse models displaying mutations or deletions in genes which encode for Ca2+ signaling-related proteins, in this review we will discuss the several pathogenic mechanisms related to deranged Ca2+ homeostasis that leads to significant Purkinje cell degeneration and dysfunction.
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Affiliation(s)
- Francesca Prestori
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy;
- Correspondence:
| | - Francesco Moccia
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, 27100 Pavia, Italy;
| | - Egidio D’Angelo
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy;
- IRCCS Mondino Foundation, 27100 Pavia, Italy
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29
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Lalonde R, Strazielle C. Motor Performances of Spontaneous and Genetically Modified Mutants with Cerebellar Atrophy. THE CEREBELLUM 2019; 18:615-634. [PMID: 30820866 DOI: 10.1007/s12311-019-01017-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Chance discovery of spontaneous mutants with atrophy of the cerebellar cortex has unearthed genes involved in optimizing motor coordination. Rotorod, stationary beam, and suspended wire tests are useful in delineating behavioral phenotypes of spontaneous mutants with cerebellar atrophy such as Grid2Lc, Grid2ho, Rorasg, Agtpbp1pcd, Relnrl, and Dab1scm. Likewise, transgenic or null mutants serving as experimental models of spinocerebellar ataxia (SCA) are phenotyped with the same tests. Among experimental models of autosomal dominant SCA, rotorod deficits were reported in SCA1 to 3, SCA5 to 8, SCA14, SCA17, and SCA27 and stationary beam deficits in SCA1 to 3, SCA5, SCA6, SCA13, SCA17, and SCA27. Beam tests are sensitive to experimental therapies of various kinds including molecules affecting glutamate signaling, mesenchymal stem cells, anti-oligomer antibodies, lentiviral vectors carrying genes, interfering RNAs, or neurotrophic factors, and interbreeding with other mutants.
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Affiliation(s)
- Robert Lalonde
- Department of Psychology, University of Rouen, 76821, Mont-Saint-Aignan Cedex, France.
| | - Catherine Strazielle
- Laboratory of Stress, Immunity, and Pathogens EA7300, and CHRU of Nancy, University of Lorraine, 54500, Vandoeuvre-les-Nancy, France
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30
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Nanou E, Catterall WA. Calcium Channels, Synaptic Plasticity, and Neuropsychiatric Disease. Neuron 2019; 98:466-481. [PMID: 29723500 DOI: 10.1016/j.neuron.2018.03.017] [Citation(s) in RCA: 276] [Impact Index Per Article: 55.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/06/2018] [Accepted: 03/09/2018] [Indexed: 12/14/2022]
Abstract
Voltage-gated calcium channels couple depolarization of the cell-surface membrane to entry of calcium, which triggers secretion, contraction, neurotransmission, gene expression, and other physiological responses. They are encoded by ten genes, which generate three voltage-gated calcium channel subfamilies: CaV1; CaV2; and CaV3. At synapses, CaV2 channels form large signaling complexes in the presynaptic nerve terminal, which are responsible for the calcium entry that triggers neurotransmitter release and short-term presynaptic plasticity. CaV1 channels form signaling complexes in postsynaptic dendrites and dendritic spines, where their calcium entry induces long-term potentiation. These calcium channels are the targets of mutations and polymorphisms that alter their function and/or regulation and cause neuropsychiatric diseases, including migraine headache, cerebellar ataxia, autism, schizophrenia, bipolar disorder, and depression. This article reviews the molecular properties of calcium channels, considers their multiple roles in synaptic plasticity, and discusses their potential involvement in this wide range of neuropsychiatric diseases.
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Affiliation(s)
- Evanthia Nanou
- Department of Pharmacology, University of Washington, Seattle, WA 98195-7280, USA
| | - William A Catterall
- Department of Pharmacology, University of Washington, Seattle, WA 98195-7280, USA.
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31
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Masi A, Narducci R, Mannaioni G. Harnessing ionic mechanisms to achieve disease modification in neurodegenerative disorders. Pharmacol Res 2019; 147:104343. [PMID: 31279830 DOI: 10.1016/j.phrs.2019.104343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/19/2019] [Accepted: 07/03/2019] [Indexed: 12/12/2022]
Abstract
Progressive neuronal death is the key pathogenic event leading to clinical symptoms in neurodegenerative disorders (NDDs). Neuroprotective treatments are virtually unavailable, partly because of the marked internal heterogeneity of the mechanisms underlying pathology. Targeted neuroprotection would require deep mechanistic knowledge across the entire aetiological spectrum of each NDD and the development of tailored treatments. Although ideal, this strategy appears challenging, as it would require a degree of characterization of both the disease and the patient that is currently unavailable. The alternate strategy is to search for commonalities across molecularly distinct NDD forms and exploit these for the development of drugs with broad-spectrum efficacy. In this view, mounting evidence points to ionic mechanisms (IMs) as targets with potential therapeutic efficacy across distinct NDD subtypes. The scope of this review is to present clinical and preclinical evidence supporting the link between disruption of IMs and neuronal death in specific NDDs and to critically revise past and ongoing attempts of harnessing IMs for the development of neuroprotective treatments.
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Affiliation(s)
- A Masi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy; School of Pharmacy, University of Camerino, Camerino, Italy.
| | - R Narducci
- Italian Institute of Technology (IIT), Department of Neuroscience and Brain Technologies, Genova, Italy
| | - G Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Florence, Italy; Toxicology Unit, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy
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32
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Sutherland HG, Albury CL, Griffiths LR. Advances in genetics of migraine. J Headache Pain 2019; 20:72. [PMID: 31226929 PMCID: PMC6734342 DOI: 10.1186/s10194-019-1017-9] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 05/24/2019] [Indexed: 02/06/2023] Open
Abstract
Background Migraine is a complex neurovascular disorder with a strong genetic component. There are rare monogenic forms of migraine, as well as more common polygenic forms; research into the genes involved in both types has provided insights into the many contributing genetic factors. This review summarises advances that have been made in the knowledge and understanding of the genes and genetic variations implicated in migraine etiology. Findings Migraine is characterised into two main types, migraine without aura (MO) and migraine with aura (MA). Hemiplegic migraine is a rare monogenic MA subtype caused by mutations in three main genes - CACNA1A, ATP1A2 and SCN1A - which encode ion channel and transport proteins. Functional studies in cellular and animal models show that, in general, mutations result in impaired glutamatergic neurotransmission and cortical hyperexcitability, which make the brain more susceptible to cortical spreading depression, a phenomenon thought to coincide with aura symptoms. Variants in other genes encoding ion channels and solute carriers, or with roles in regulating neurotransmitters at neuronal synapses, or in vascular function, can also cause monogenic migraine, hemiplegic migraine and related disorders with overlapping symptoms. Next-generation sequencing will accelerate the finding of new potentially causal variants and genes, with high-throughput bioinformatics analysis methods and functional analysis pipelines important in prioritising, confirming and understanding the mechanisms of disease-causing variants. With respect to common migraine forms, large genome-wide association studies (GWAS) have greatly expanded our knowledge of the genes involved, emphasizing the role of both neuronal and vascular pathways. Dissecting the genetic architecture of migraine leads to greater understanding of what underpins relationships between subtypes and comorbid disorders, and may have utility in diagnosis or tailoring treatments. Further work is required to identify causal polymorphisms and the mechanism of their effect, and studies of gene expression and epigenetic factors will help bridge the genetics with migraine pathophysiology. Conclusions The complexity of migraine disorders is mirrored by their genetic complexity. A comprehensive knowledge of the genetic factors underpinning migraine will lead to improved understanding of molecular mechanisms and pathogenesis, to enable better diagnosis and treatments for migraine sufferers.
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Affiliation(s)
- Heidi G Sutherland
- Genomics Research Centre, Institute of Health and Biomedical Innovation. School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Cassie L Albury
- Genomics Research Centre, Institute of Health and Biomedical Innovation. School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, Institute of Health and Biomedical Innovation. School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD, Australia.
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33
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Hashiguchi S, Doi H, Kunii M, Nakamura Y, Shimuta M, Suzuki E, Koyano S, Okubo M, Kishida H, Shiina M, Ogata K, Hirashima F, Inoue Y, Kubota S, Hayashi N, Nakamura H, Takahashi K, Katsumoto A, Tada M, Tanaka K, Sasaoka T, Miyatake S, Miyake N, Saitsu H, Sato N, Ozaki K, Ohta K, Yokota T, Mizusawa H, Mitsui J, Ishiura H, Yoshimura J, Morishita S, Tsuji S, Takeuchi H, Ishikawa K, Matsumoto N, Ishikawa T, Tanaka F. Ataxic phenotype with altered Ca V3.1 channel property in a mouse model for spinocerebellar ataxia 42. Neurobiol Dis 2019; 130:104516. [PMID: 31229688 DOI: 10.1016/j.nbd.2019.104516] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 06/06/2019] [Accepted: 06/19/2019] [Indexed: 11/16/2022] Open
Abstract
Spinocerebellar ataxia 42 (SCA42) is a neurodegenerative disorder recently shown to be caused by c.5144G > A (p.Arg1715His) mutation in CACNA1G, which encodes the T-type voltage-gated calcium channel CaV3.1. Here, we describe a large Japanese family with SCA42. Postmortem pathological examination revealed severe cerebellar degeneration with prominent Purkinje cell loss without ubiquitin accumulation in an SCA42 patient. To determine whether this mutation causes ataxic symptoms and neurodegeneration, we generated knock-in mice harboring c.5168G > A (p.Arg1723His) mutation in Cacna1g, corresponding to the mutation identified in the SCA42 family. Both heterozygous and homozygous mutants developed an ataxic phenotype from the age of 11-20 weeks and showed Purkinje cell loss at 50 weeks old. Degenerative change of Purkinje cells and atrophic thinning of the molecular layer were conspicuous in homozygous knock-in mice. Electrophysiological analysis of Purkinje cells using acute cerebellar slices from young mice showed that the point mutation altered the voltage dependence of CaV3.1 channel activation and reduced the rebound action potentials after hyperpolarization, although it did not significantly affect the basic properties of synaptic transmission onto Purkinje cells. Finally, we revealed that the resonance of membrane potential of neurons in the inferior olivary nucleus was decreased in knock-in mice, which indicates that p.Arg1723His CaV3.1 mutation affects climbing fiber signaling to Purkinje cells. Altogether, our study shows not only that a point mutation in CACNA1G causes an ataxic phenotype and Purkinje cell degeneration in a mouse model, but also that the electrophysiological abnormalities at an early stage of SCA42 precede Purkinje cell loss.
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Affiliation(s)
- Shunta Hashiguchi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Hiroshi Doi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Misako Kunii
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Yukihiro Nakamura
- Department of Pharmacology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Misa Shimuta
- Department of Pharmacology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Etsuko Suzuki
- Department of Pharmacology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Shigeru Koyano
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Masaki Okubo
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Hitaru Kishida
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Masaaki Shiina
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Kazuhiro Ogata
- Department of Biochemistry, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Fumiko Hirashima
- Department of Rehabilitation Medicine, Flower and Forest Tokyo Hospital, 2-3-6 Nishigahara, Kita-ku, Tokyo 114-0024, Japan
| | - Yukichi Inoue
- Department of Neurology, Toyama Prefectural Rehabilitation Hospital and Support Center for Children with Disabilities, 36 Shimoiino, Toyama 931-8517, Japan
| | - Shun Kubota
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Noriko Hayashi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Haruko Nakamura
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Keita Takahashi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Atsuko Katsumoto
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Mikiko Tada
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Kenichi Tanaka
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Toshikuni Sasaoka
- Department of Comparative and Experimental Medicine, Center for Bioresource-based Researches, Brain Research Institute, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata 951-8585, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Hirotomo Saitsu
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Nozomu Sato
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Kokoro Ozaki
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Kiyobumi Ohta
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Hidehiro Mizusawa
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Jun Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Jun Yoshimura
- Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Shinichi Morishita
- Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Hideyuki Takeuchi
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Kinya Ishikawa
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-0034, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan
| | - Taro Ishikawa
- Department of Pharmacology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461, Japan.
| | - Fumiaki Tanaka
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
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Du X, Wei C, Hejazi Pastor DP, Rao ER, Li Y, Grasselli G, Godfrey J, Palmenberg AC, Andrade J, Hansel C, Gomez CM. α1ACT Is Essential for Survival and Early Cerebellar Programming in a Critical Neonatal Window. Neuron 2019; 102:770-785.e7. [PMID: 30922876 DOI: 10.1016/j.neuron.2019.02.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 12/17/2018] [Accepted: 02/20/2019] [Indexed: 10/27/2022]
Abstract
Postnatal cerebellar development is a precisely regulated process involving well-orchestrated expression of neural genes. Neurological phenotypes associated with CACNA1A gene defects have been increasingly recognized, yet the molecular principles underlying this association remain elusive. By characterizing a dose-dependent CACNA1A gene deficiency mouse model, we discovered that α1ACT, as a transcription factor and secondary protein of CACNA1A mRNA, drives dynamic gene expression networks within cerebellar Purkinje cells and is indispensable for neonatal survival. Perinatal loss of α1ACT leads to motor dysfunction through disruption of neurogenesis and synaptic regulatory networks. However, its elimination in adulthood has minimal effect on the cerebellum. These findings shed light on the critical role of α1ACT in facilitating neuronal development in both mice and humans and support a rationale for gene therapies for calcium-channel-associated cerebellar disorders. Finally, we show that bicistronic expression may be common to the voltage-gated calcium channel (VGCC) gene family and may help explain complex genetic syndromes.
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Affiliation(s)
- Xiaofei Du
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Cenfu Wei
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | | | - Eshaan R Rao
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Yan Li
- Center for Research Informatics, University of Chicago, Chicago, IL 60637, USA
| | - Giorgio Grasselli
- Department of Neurobiology, University of Chicago, Chicago, IL 60637, USA; Center for Synaptic Neuroscience and Technology, Italian Institute of Technology (IIT), L.go R. Benzi 10, 16132 Genova, Italy
| | - Jack Godfrey
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Ann C Palmenberg
- Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jorge Andrade
- Center for Research Informatics, University of Chicago, Chicago, IL 60637, USA; Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
| | - Christian Hansel
- Department of Neurobiology, University of Chicago, Chicago, IL 60637, USA
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Pastor PDH, Du X, Fazal S, Davies AN, Gomez CM. Targeting the CACNA1A IRES as a Treatment for Spinocerebellar Ataxia Type 6. THE CEREBELLUM 2019; 17:72-77. [PMID: 29374372 DOI: 10.1007/s12311-018-0917-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We have discovered that the P/Q-type voltage-gated Ca2+ channel (VGCC) gene, CACNA1A, encodes both the α1A (Cav2.1) subunit and a newly recognized transcription factor, α1ACT, by means of a novel internal ribosomal entry site (IRES) within the α1A C-terminal coding region. α1ACT, when mutated with an expansion of the polyglutamine tract in the C-terminus, gives rise to spinocerebellar ataxia type 6 (SCA6). Because silencing of the entire CACNA1A gene would result in the loss of the essential Cav2.1 channel, the IRES controlling α1ACT expression is an excellent target for selective silencing of α1ACT as a therapeutic intervention for SCA6. We performed a high-throughput screen of FDA-approved small molecules using a dual luciferase reporter system and identified ten hits able to selectively inhibit the IRES. We identified four main candidates that showed selective suppression of α1ACT relative to α1A in HEK cells expressing a native CACNA1A vector. We previously pursued another avenue of molecular intervention through miRNA silencing. We studied three human miRNAs (miRNA-711, -3191-5p, -4786) that would potentially bind to sequences within the CACNA1A IRES region, based on an miRNA prediction program. Only miRNA-3191-5p was found to selectively inhibit the translation of α1ACT in cells. We developed a hyperacute model of SCA6 in mice by injecting a pathogenic form of the IRES-mediated α1ACT (AAV9-α1ACTQ33). Finally, we tested the effectiveness of the miRNA therapy by co-expressing either control miRNA or miRNA-3191-5p and found that miRNA-3191-5p decreased the levels of α1ACTQ33 and prevented the hyperacute disease in mice. These studies provide the proof of principle that a therapy directed at selectively preventing α1ACT expression could be used to treat SCA6.
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Affiliation(s)
| | - Xiaofei Du
- Department of Neurology, University of Chicago, Chicago, IL, 60637, USA
| | - Sarah Fazal
- Cellular Screening Center Core, University of Chicago, Chicago, IL, 60637, USA
| | - Andre N Davies
- Department of Medicine, University of Chicago, Chicago, IL, 60637, USA
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Tara E, Vitenzon A, Hess E, Khodakhah K. Aberrant cerebellar Purkinje cell activity as the cause of motor attacks in a mouse model of episodic ataxia type 2. Dis Model Mech 2018; 11:11/9/dmm034181. [PMID: 30279196 PMCID: PMC6177005 DOI: 10.1242/dmm.034181] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 07/30/2018] [Indexed: 11/20/2022] Open
Abstract
Many cerebellar-induced neurological disorders, such as ataxias and cerebellar-induced dystonias, are associated with abnormal Purkinje cell activity. In tottering mice, a well-established mouse model of episodic ataxia type 2 (EA2), cerebellar Purkinje cells are required for the initiation of motor attacks. How Purkinje cells contribute to the initiation of attacks is not known, and to date there are no reports on the activity of Purkinje cells during motor attacks in the tottering mice. Here, we show that tottering Purkinje cells exhibit high-frequency burst firing during attacks, reminiscent of other mouse models of cerebellar-induced motor dysfunction. We recorded the activity of Purkinje cells in awake head-restrained tottering mice at baseline, or during caffeine-induced attacks. During motor attacks, firing of Purkinje cells transformed to high-frequency burst firing. Interestingly, the extent to which the activity of Purkinje cells was erratic was correlated with the severity of the motor dysfunction. In support of a causal role for erratic activity in generating motor dysfunction, we found that direct infusion of the small conductance calcium-activated potassium (SK) channel activator NS309 into the cerebellum of tottering mice in the midst of an attack normalized the firing of Purkinje cells and aborted attacks. Conversely, we found that inducing high-frequency burst firing of Purkinje cells in wild-type animals is sufficient to produce severe motor signs. We report that erratic activity of wild-type Purkinje cells results in ataxia and dystonic postures. Moreover, this aberrant activity is the cause of motor attacks in the tottering mice. Summary: Here, we report that in the well-established mouse model of episodic ataxia type 2, tottering, the severe episodic motor signs are caused by highly erratic activity of Purkinje cells.
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Affiliation(s)
- Esra Tara
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ariel Vitenzon
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ellen Hess
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322-3090, USA
| | - Kamran Khodakhah
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Indelicato E, Nachbauer W, Karner E, Eigentler A, Wagner M, Unterberger I, Poewe W, Delazer M, Boesch S. The neuropsychiatric phenotype in CACNA1A mutations: a retrospective single center study and review of the literature. Eur J Neurol 2018; 26:66-e7. [PMID: 30063100 DOI: 10.1111/ene.13765] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 07/24/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND PURPOSE CACNA1A encodes the α1 subunit of the neuronal calcium channel P/Q. CACNA1A mutations underlie three allelic disorders: familial hemiplegic migraine type 1 (FHM1), episodic ataxia type 2 (EA2) and spinocerebellar ataxia type 6 (SCA6). A clear-cut genotype-phenotype correlation is often lacking since clinical manifestations may overlap. Several case reports have described cognitive and behavioral features in CACNA1A disorders, but studies in larger case series are lacking. METHODS Genetically confirmed CACNA1A cases were retrieved from the database of the ataxia outpatient clinic of the Department of Neurology at Innsbruck Medical University. Clinical charts and neuropsychological test results were retrospectively analyzed. In addition, a review of the literature including only genetically confirmed cases was performed. RESULTS Forty-four CACNA1A cases were identified in our database. Delayed psychomotor milestones and poor school performance were described in seven (four FHM1, three EA2) and eight (three FHM1, five EA2) patients, respectively. Psychiatric comorbidities were diagnosed in eight patients (two FHM1, six EA2). Neuropsychological testing was available for 23 patients (11 FHM1, 10 EA2, two SCA6). Various cognitive deficits were documented in 21 cases (all patients except one SCA6). Impairments were predominantly seen in figural memory, visuoconstructive abilities and verbal fluency. In the literature, an early psychomotor delay is described in several children with EA2 and FHM1, whilst reports of cognitive and psychiatric findings from adult cases are scarce. CONCLUSIONS Neuropsychiatric manifestations are common in episodic CACNA1A disorders. In the case of otherwise unexplained developmental delay and a positive family history, CACNA1A mutations should be considered in the differential diagnosis.
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Affiliation(s)
- E Indelicato
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - W Nachbauer
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - E Karner
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - A Eigentler
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - M Wagner
- Department of Neuroradiology, Innsbruck Medical University, Innsbruck, Austria
| | - I Unterberger
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - W Poewe
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - M Delazer
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
| | - S Boesch
- Department of Neurology, Innsbruck Medical University, Innsbruck, Austria
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Hoxha E, Balbo I, Miniaci MC, Tempia F. Purkinje Cell Signaling Deficits in Animal Models of Ataxia. Front Synaptic Neurosci 2018; 10:6. [PMID: 29760657 PMCID: PMC5937225 DOI: 10.3389/fnsyn.2018.00006] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/09/2018] [Indexed: 12/19/2022] Open
Abstract
Purkinje cell (PC) dysfunction or degeneration is the most frequent finding in animal models with ataxic symptoms. Mutations affecting intrinsic membrane properties can lead to ataxia by altering the firing rate of PCs or their firing pattern. However, the relationship between specific firing alterations and motor symptoms is not yet clear, and in some cases PC dysfunction precedes the onset of ataxic signs. Moreover, a great variety of ionic and synaptic mechanisms can affect PC signaling, resulting in different features of motor dysfunction. Mutations affecting Na+ channels (NaV1.1, NaV1.6, NaVβ4, Fgf14 or Rer1) reduce the firing rate of PCs, mainly via an impairment of the Na+ resurgent current. Mutations that reduce Kv3 currents limit the firing rate frequency range. Mutations of Kv1 channels act mainly on inhibitory interneurons, generating excessive GABAergic signaling onto PCs, resulting in episodic ataxia. Kv4.3 mutations are responsible for a complex syndrome with several neurologic dysfunctions including ataxia. Mutations of either Cav or BK channels have similar consequences, consisting in a disruption of the firing pattern of PCs, with loss of precision, leading to ataxia. Another category of pathogenic mechanisms of ataxia regards alterations of synaptic signals arriving at the PC. At the parallel fiber (PF)-PC synapse, mutations of glutamate delta-2 (GluD2) or its ligand Crbl1 are responsible for the loss of synaptic contacts, abolishment of long-term depression (LTD) and motor deficits. At the same synapse, a correct function of metabotropic glutamate receptor 1 (mGlu1) receptors is necessary to avoid ataxia. Failure of climbing fiber (CF) maturation and establishment of PC mono-innervation occurs in a great number of mutant mice, including mGlu1 and its transduction pathway, GluD2, semaphorins and their receptors. All these models have in common the alteration of PC output signals, due to a variety of mechanisms affecting incoming synaptic signals or the way they are processed by the repertoire of ionic channels responsible for intrinsic membrane properties. Although the PC is a final common pathway of ataxia, the link between specific firing alterations and neurologic symptoms has not yet been systematically studied and the alterations of the cerebellar contribution to motor signals are still unknown.
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Affiliation(s)
- Eriola Hoxha
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Turin, Italy.,Department of Neuroscience, University of Torino, Turin, Italy
| | - Ilaria Balbo
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Turin, Italy.,Department of Neuroscience, University of Torino, Turin, Italy
| | - Maria Concetta Miniaci
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Filippo Tempia
- Neuroscience Institute Cavalieri Ottolenghi (NICO), Turin, Italy.,Department of Neuroscience, University of Torino, Turin, Italy.,National Institute of Neuroscience (INN), Turin, Italy
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Aikawa T, Watanabe T, Miyazaki T, Mikuni T, Wakamori M, Sakurai M, Aizawa H, Ishizu N, Watanabe M, Kano M, Mizusawa H, Watase K. Alternative splicing in the C-terminal tail of Cav2.1 is essential for preventing a neurological disease in mice. Hum Mol Genet 2018; 26:3094-3104. [PMID: 28510727 DOI: 10.1093/hmg/ddx193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Accepted: 05/09/2017] [Indexed: 12/13/2022] Open
Abstract
Alternative splicing (AS) that occurs at the final coding exon (exon 47) of the Cav2.1 voltage-gated calcium channel (VGCC) gene produces two major isoforms in the brain, MPI and MPc. These isoforms differ in their splice acceptor sites; human MPI is translated into a polyglutamine tract associated with spinocerebellar ataxia type 6 (SCA6), whereas MPc splices to an immediate stop codon, resulting in a shorter cytoplasmic tail. To gain insight into the functional role of the AS in vivo and whether modulating the splice patterns at this locus can be a potential therapeutic strategy for SCA6, here we created knockin mice that exclusively express MPc by inserting the splice-site mutation. The resultant Cacna1aCtmKO/CtmKO mice developed non-progressive neurological phenotypes, featuring early-onset ataxia and absence seizure without significant alterations in the basic properties of the channel. Interactions of Cav2.1 with Cavβ4 and Rimbp2 were significantly reduced while those with GABAB2 were enhanced in the cerebellum of Cacna1aCtmKO/CtmKO mice. Treatment with the GABAB antagonist CGP35348 partially rescued the motor impairments seen in Cacna1aCtmKO/CtmKO mice. These results suggest that the carboxyl-terminal domain of Cav2.1 is not essential for maintaining the basic properties of the channel in the cerebellar Purkinje neurons but is involved in multiple interactions of Cav2.1 with other proteins, and plays an essential role in preventing a complex neurological disease.
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Affiliation(s)
- Tomonori Aikawa
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.,Core Research for Evolutional Science and Technology (CREST) of the Japan Science and Technology (JST), Tokyo 102-8666, Japan
| | - Takaki Watanabe
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Taisuke Miyazaki
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, Japan
| | - Takayasu Mikuni
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan.,Max Planck Florida Institute for Neuroscience, Max Planck Way Jupiter, FL 33458, USA
| | - Minoru Wakamori
- Department of Oral Biology, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan
| | - Miyano Sakurai
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Hidenori Aizawa
- Laboratory of Molecular Neuroscience, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
| | - Nobutaka Ishizu
- Department of Neurology, Tokyo National Hospital, Tokyo, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, Japan
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Hidehiro Mizusawa
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.,Core Research for Evolutional Science and Technology (CREST) of the Japan Science and Technology (JST), Tokyo 102-8666, Japan.,Department of Neurology and Neurological Science, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.,National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan
| | - Kei Watase
- Center for Brain Integration Research, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.,Core Research for Evolutional Science and Technology (CREST) of the Japan Science and Technology (JST), Tokyo 102-8666, Japan
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40
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Abstract
Spinocerebellar ataxias (SCAs) are a genetically diverse group of dominantly inherited disorders that share clinical features that result from dysfunction and degeneration of the cerebellum and its associated pathways. Although nearly 40 genes are currently recognized to result in SCA, shared mechanisms for disease pathogenesis exist among subsets of the SCAs. The most common SCAs result from a glutamine-encoding CAG repeat in the respective disease genes. This chapter discusses the varied genetic etiology of SCA and attempts to categorize these disorders based on shared mechanisms of disease. We also summarize evaluation and management for the SCAs.
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Affiliation(s)
- Andrew Mundwiler
- Department of Neurosciences, Spectrum Health, Grand Rapids, MI, United States; College of Human Medicine, Michigan State University, Grand Rapids, MI, United States
| | - Vikram G Shakkottai
- Department of Neurology, University of Michigan, Ann Arbor, MI, United States.
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41
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Du X, Gomez CM. Spinocerebellar [corrected] Ataxia Type 6: Molecular Mechanisms and Calcium Channel Genetics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1049:147-173. [PMID: 29427102 DOI: 10.1007/978-3-319-71779-1_7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Spinocerebellar ataxia (SCA) type 6 is an autosomal dominant disease affecting cerebellar degeneration. Clinically, it is characterized by pure cerebellar dysfunction, slowly progressive unsteadiness of gait and stance, slurred speech, and abnormal eye movements with late onset. Pathological findings of SCA6 include a diffuse loss of Purkinje cells, predominantly in the cerebellar vermis. Genetically, SCA6 is caused by expansion of a trinucleotide CAG repeat in the last exon of longest isoform CACNA1A gene on chromosome 19p13.1-p13.2. Normal alleles have 4-18 repeats, while alleles causing disease contain 19-33 repeats. Due to presence of a novel internal ribosomal entry site (IRES) with the mRNA, CACNA1A encodes two structurally unrelated proteins with distinct functions within an overlapping open reading frame (ORF) of the same mRNA: (1) α1A subunit of P/Q-type voltage gated calcium channel; (2) α1ACT, a newly recognized transcription factor, with polyglutamine repeat at C-terminal end. Understanding the function of α1ACT in physiological and pathological conditions may elucidate the pathogenesis of SCA6. More importantly, the IRES, as the translational control element of α1ACT, provides a potential therapeutic target for the treatment of SCA6.
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Affiliation(s)
- Xiaofei Du
- Department of Neurology, The University of Chicago, Chicago, 60637, IL, USA
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42
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Miyazaki Y, Du X, Muramatsu SI, Gomez CM. An miRNA-mediated therapy for SCA6 blocks IRES-driven translation of the CACNA1A second cistron. Sci Transl Med 2017; 8:347ra94. [PMID: 27412786 DOI: 10.1126/scitranslmed.aaf5660] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/21/2016] [Indexed: 12/17/2022]
Abstract
Spinocerebellar ataxia type 6 (SCA6) is a dominantly inherited neurodegenerative disease characterized by slowly progressive ataxia and Purkinje cell degeneration. SCA6 is caused by a polyglutamine repeat expansion within a second CACNA1A gene product, α1ACT. α1ACT expression is under the control of an internal ribosomal entry site (IRES) present within the CACNA1A coding region. Whereas SCA6 allele knock-in mice show indistinguishable phenotypes from wild-type littermates, expression of SCA6-associated α1ACT (α1ACTSCA6) driven by a Purkinje cell-specific promoter in mice produces slowly progressive ataxia and cerebellar atrophy. We developed an early-onset SCA6 mouse model using an adeno-associated virus (AAV)-based gene delivery system to ectopically express CACNA1A IRES-driven α1ACTSCA6 to test the potential of CACNA1A IRES-targeting therapies. Mice expressing AAV9-mediated CACNA1A IRES-driven α1ACTSCA6 exhibited early-onset ataxia, motor deficits, and Purkinje cell degeneration. We identified miR-3191-5p as a microRNA (miRNA) that targeted CACNA1A IRES and preferentially inhibited the CACNA1A IRES-driven translation of α1ACT in an Argonaute 4 (Ago4)-dependent manner. We found that eukaryotic initiation factors (eIFs), eIF4AII and eIF4GII, interacted with the CACNA1A IRES to enhance α1ACT translation. Ago4-bound miR-3191-5p blocked the interaction of eIF4AII and eIF4GII with the CACNA1A IRES, attenuating IRES-driven α1ACT translation. Furthermore, AAV9-mediated delivery of miR-3191-5p protected mice from the ataxia, motor deficits, and Purkinje cell degeneration caused by CACNA1A IRES-driven α1ACTSCA6 We have established proof of principle that viral delivery of an miRNA can rescue a disease phenotype through modulation of cellular IRES activity in a mouse model.
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Affiliation(s)
- Yu Miyazaki
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Xiaofei Du
- Department of Neurology, University of Chicago, Chicago, IL 60637, USA
| | - Shin-Ichi Muramatsu
- Division of Neurology, Department of Medicine, Jichi Medical University, Tochigi 3290498, Japan. Center for Gene and Cell Therapy, Institute of Medical Science, University of Tokyo, Tokyo 1088639, Japan
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Rentiya Z, Khan NS, Ergun E, Ying SH, Desmond JE. Distinct cerebellar regions related to motor and cognitive performance in SCA6 patients. Neuropsychologia 2017; 107:25-30. [PMID: 29100951 PMCID: PMC5705404 DOI: 10.1016/j.neuropsychologia.2017.10.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 10/10/2017] [Accepted: 10/30/2017] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To demonstrate a correlation between anatomic regional changes in Spinocerebellar Ataxia type 6 (SCA6) patients and measures of cognitive performance on neuropsychological tests. METHODS Neurocognitive testing was conducted on 24 SCA6 and 28 control subjects. For each cognitive test, SCA6 patients were compared against the controls using Student's t-test. For the cerebellar patients, using voxel based morphometry, correlations between cerebellar gray matter volume at each voxel and performance on the neuropsychological exams were calculated using the Pearson correlation coefficient implemented in SPM8. RESULTS Compared to controls, SCA6 patients exhibited significantly impaired performance on the following cognitive tests: Rey-Auditory Verbal Learning Test Trial V, Controlled Oral Word Association phonemic test and semantic-verb test, Rey-Osterrieth Complex Figure copy test as well as immediate and delayed visuo-spatial memory recall test, Trail Making Test (TMT) Part A and Part B, Stroop Color Task completion time, Stroop Color-Word Task score, and Grooved Pegboard Test (GPT) Dominant and Non-Dominant Hand time. Correlations of gray matter density with cognitive test performance were determined for all SCA6 subjects. Using a p-value threshold of 0.001 and family-wise small volume error correction, significant correlations were found for GPT Non-Dominant, GPT Dominant, TMT Part A, and TMT Part B. CONCLUSION Different regional patterns of cerebellar involvement were found for the motoric GPT task and the executive version of the TMT. The results for the GPT strongly indicated that the integrity of medial superior hemispheric regions was associated with motor task performance, whereas executive cognitive function was localized in distinctly different inferior regions. This is the first VBM study to differentiate cognitive and motor contributions of the cerebellum.
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Affiliation(s)
- Zubir Rentiya
- Johns Hopkins University School of Medicine, Department Radiology, Neurology, Ophthalmology, United States.
| | - Noore-Sabah Khan
- Johns Hopkins University School of Medicine, Department Radiology, Neurology, Ophthalmology, United States.
| | - Ezgi Ergun
- Johns Hopkins Whiting School of Engineering, Department of Electrical and Computer Engineering, United States.
| | - Sarah H Ying
- Johns Hopkins University School of Medicine, Department Radiology, Neurology, Ophthalmology, United States.
| | - John E Desmond
- Johns Hopkins University School of Medicine, Department of Neurology, Neuroscience, Cognitive Science, United States.
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Rima M, Daghsni M, Lopez A, Fajloun Z, Lefrancois L, Dunach M, Mori Y, Merle P, Brusés JL, De Waard M, Ronjat M. Down-regulation of the Wnt/β-catenin signaling pathway by Cacnb4. Mol Biol Cell 2017; 28:3699-3708. [PMID: 29021340 PMCID: PMC5706996 DOI: 10.1091/mbc.e17-01-0076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 10/02/2017] [Accepted: 10/04/2017] [Indexed: 11/29/2022] Open
Abstract
The β4 isoform of the β-subunits of voltage-gated calcium channel regulates cell proliferation and cell cycle progression. Herein we show that coexpression of the β4-subunit with actors of the canonical Wnt/β-catenin signaling pathway in a hepatoma cell line inhibits Wnt-responsive gene transcription and decreases cell division, in agreement with the role of the Wnt pathway in cell proliferation. β4-subunit-mediated inhibition of Wnt signaling is observed in the presence of LiCl, an inhibitor of glycogen synthase kinase (GSK3) that promotes β-catenin translocation to the nucleus. Expression of β4-subunit mutants that lost the ability to translocate to the nucleus has no effect on Wnt signaling, suggesting that β4-subunit inhibition of Wnt signaling occurs downstream from GSK3 and requires targeting of β4-subunit to the nucleus. β4-subunit coimmunoprecipitates with the TCF4 transcription factor and overexpression of TCF4 reverses the effect of β4-subunit on the Wnt pathway. We thus propose that the interaction of nuclear β4-subunit with TCF4 prevents β-catenin binding to TCF4 and leads to the inhibition of the Wnt-responsive gene transcription. Thereby, our results show that β4-subunit is a TCF4 repressor and therefore appears as an interesting candidate for the regulation of this pathway in neurons where β4-subunit is specifically expressed.
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Affiliation(s)
- Mohamad Rima
- L'institut du thorax, INSER, CNRS, Université de Nantes, 44000 Nantes, France
- LabEx Ion Channels Science and Therapeutics, Valbone 06560, France
- Azm Center for Research in Biotechnology and Its Application, Lebanese University, 1300 Tripoli, Lebanon
| | - Marwa Daghsni
- L'institut du thorax, INSER, CNRS, Université de Nantes, 44000 Nantes, France
- Université de Tunis El Manar, Faculté de Médecine de Tunis, LR99ES10 Laboratoire de Génétique Humaine, 1007 Tunis, Tunisie
| | - Anaïs Lopez
- INSERM U1052, Team on Hepatocarcinogenesis and Viral Infections, Centre of Research in Cancerology of Lyon, Claude Bernard Lyon 1 University, 69100 Villeurbanne, France
- Hepatology Unit, Croix-Rousse Hospital, 69000 Lyon, France
| | - Ziad Fajloun
- Azm Center for Research in Biotechnology and Its Application, Lebanese University, 1300 Tripoli, Lebanon
| | - Lydie Lefrancois
- INSERM U1052, Team on Hepatocarcinogenesis and Viral Infections, Centre of Research in Cancerology of Lyon, Claude Bernard Lyon 1 University, 69100 Villeurbanne, France
- Hepatology Unit, Croix-Rousse Hospital, 69000 Lyon, France
| | - Mireia Dunach
- Departament de Bioquímica i Biologia Molecular, CEB, Facultat de Medicina, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - Yasuo Mori
- Department of Synthetic Chemistry and Biological Chemistry, Laboratory of Molecular Biology, Graduate School of Engineering, Kyoto University, 615-8510 Kyoto, Japan
| | - Philippe Merle
- INSERM U1052, Team on Hepatocarcinogenesis and Viral Infections, Centre of Research in Cancerology of Lyon, Claude Bernard Lyon 1 University, 69100 Villeurbanne, France
- Hepatology Unit, Croix-Rousse Hospital, 69000 Lyon, France
| | - Juan L Brusés
- Department of Natural Sciences, Mercy College, Dobbs Ferry, NY 10522
| | - Michel De Waard
- L'institut du thorax, INSER, CNRS, Université de Nantes, 44000 Nantes, France
- LabEx Ion Channels Science and Therapeutics, Valbone 06560, France
- Smartox Biotechnology, 38400 Saint-Martin d'Hères, France
| | - Michel Ronjat
- L'institut du thorax, INSER, CNRS, Université de Nantes, 44000 Nantes, France
- LabEx Ion Channels Science and Therapeutics, Valbone 06560, France
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45
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Bavassano C, Eigentler A, Stanika R, Obermair GJ, Boesch S, Dechant G, Nat R. Bicistronic CACNA1A Gene Expression in Neurons Derived from Spinocerebellar Ataxia Type 6 Patient-Induced Pluripotent Stem Cells. Stem Cells Dev 2017; 26:1612-1625. [PMID: 28946818 PMCID: PMC5684673 DOI: 10.1089/scd.2017.0085] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Spinocerebellar ataxia type 6 (SCA6) is an autosomal-dominant neurodegenerative disorder that is caused by a CAG trinucleotide repeat expansion in the CACNA1A gene. As one of the few bicistronic genes discovered in the human genome, CACNA1A encodes not only the α1A subunit of the P/Q type voltage-gated Ca2+ channel CaV2.1 but also the α1ACT protein, a 75 kDa transcription factor sharing the sequence of the cytoplasmic C-terminal tail of the α1A subunit. Isoforms of both proteins contain the polyglutamine (polyQ) domain that is expanded in SCA6 patients. Although certain SCA6 phenotypes appear to be specific for Purkinje neurons, other pathogenic effects of the SCA6 polyQ mutation can affect a broad spectrum of central nervous system (CNS) neuronal subtypes. We investigated the expression and function of CACNA1A gene products in human neurons derived from induced pluripotent stem cells from two SCA6 patients. Expression levels of CACNA1A encoding α1A subunit were similar between SCA6 and control neurons, and no differences were found in the subcellular distribution of CaV2.1 channel protein. The α1ACT immunoreactivity was detected in the majority of cell nuclei of SCA6 and control neurons. Although no SCA6 genotype-dependent differences in CaV2.1 channel function were observed, they were found in the expression levels of the α1ACT target gene Granulin (GRN) and in glutamate-induced cell vulnerability.
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Affiliation(s)
- Carlo Bavassano
- 1 Institute for Neuroscience, Medical University of Innsbruck , Innsbruck, Austria
| | - Andreas Eigentler
- 1 Institute for Neuroscience, Medical University of Innsbruck , Innsbruck, Austria
| | - Ruslan Stanika
- 2 Division of Physiology, Medical University of Innsbruck , Innsbruck, Austria
| | - Gerald J Obermair
- 2 Division of Physiology, Medical University of Innsbruck , Innsbruck, Austria
| | - Sylvia Boesch
- 3 Department of Neurology, Medical University of Innsbruck , Innsbruck, Austria
| | - Georg Dechant
- 1 Institute for Neuroscience, Medical University of Innsbruck , Innsbruck, Austria
| | - Roxana Nat
- 1 Institute for Neuroscience, Medical University of Innsbruck , Innsbruck, Austria
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46
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Pflieger LT, Dansithong W, Paul S, Scoles DR, Figueroa KP, Meera P, Otis TS, Facelli JC, Pulst SM. Gene co-expression network analysis for identifying modules and functionally enriched pathways in SCA2. Hum Mol Genet 2017; 26:3069-3080. [PMID: 28525545 PMCID: PMC5886232 DOI: 10.1093/hmg/ddx191] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 04/22/2017] [Accepted: 05/11/2017] [Indexed: 12/22/2022] Open
Abstract
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease caused by CAG repeat expansion in the ATXN2 gene. The repeat resides in an encoded region of the gene resulting in polyglutamine (polyQ) expansion which has been assumed to result in gain of function, predominantly, for the ATXN2 protein. We evaluated temporal cerebellar expression profiles by RNA sequencing of ATXN2Q127 mice versus wild-type (WT) littermates. ATXN2Q127 mice are characterized by a progressive motor phenotype onset, and have progressive cerebellar molecular and neurophysiological (Purkinje cell firing frequency) phenotypes. Our analysis revealed previously uncharacterized early and progressive abnormal patterning of cerebellar gene expression. Weighted Gene Coexpression Network Analysis revealed four gene modules that were significantly correlated with disease status, composed primarily of genes associated with GTPase signaling, calcium signaling and cell death. Of these genes, few overlapped with differentially expressed cerebellar genes that we identified in Atxn2-/- knockout mice versus WT littermates, suggesting that loss-of-function is not a significant component of disease pathology. We conclude that SCA2 is a disease characterized by gain of function for ATXN2.
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Affiliation(s)
| | - Warunee Dansithong
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Daniel R. Scoles
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
| | - Pratap Meera
- Department of Neurobiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Thomas S. Otis
- Department of Neurobiology, University of California Los Angeles, Los Angeles, CA, USA
| | | | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, UT 84112, USA
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47
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Sutherland HG, Griffiths LR. Genetics of Migraine: Insights into the Molecular Basis of Migraine Disorders. Headache 2017; 57:537-569. [PMID: 28271496 DOI: 10.1111/head.13053] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 01/09/2017] [Indexed: 12/20/2022]
Abstract
Migraine is a complex, debilitating neurovascular disorder, typically characterized by recurring, incapacitating attacks of severe headache often accompanied by nausea and neurological disturbances. It has a strong genetic basis demonstrated by rare migraine disorders caused by mutations in single genes (monogenic), as well as familial clustering of common migraine which is associated with polymorphisms in many genes (polygenic). Hemiplegic migraine is a dominantly inherited, severe form of migraine with associated motor weakness. Family studies have found that mutations in three different ion channels genes, CACNA1A, ATP1A2, and SCN1A can be causal. Functional studies of these mutations has shown that they can result in defective regulation of glutamatergic neurotransmission and the excitatory/inhibitory balance in the brain, which lowers the threshold for cortical spreading depression, a wave of cortical depolarization thought to be involved in headache initiation mechanisms. Other putative genes for monogenic migraine include KCKN18, PRRT2, and CSNK1D, which can also be involved with other disorders. There are a number of primarily vascular disorders caused by mutations in single genes, which are often accompanied by migraine symptoms. Mutations in NOTCH3 causes cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a hereditary cerebrovascular disease that leads to ischemic strokes and dementia, but in which migraine is often present, sometimes long before the onset of other symptoms. Mutations in the TREX1 and COL4A1 also cause vascular disorders, but often feature migraine. With respect to common polygenic migraine, genome-wide association studies have now identified single nucleotide polymorphisms at 38 loci significantly associated with migraine risk. Functions assigned to the genes in proximity to these loci suggest that both neuronal and vascular pathways also contribute to the pathophysiology of common migraine. Further studies are required to fully understand these findings and translate them into treatment options for migraine patients.
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Affiliation(s)
- Heidi G Sutherland
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, QUT, Musk Ave, Kelvin Grove, QLD, 4059, Australia
| | - Lyn R Griffiths
- Genomics Research Centre, School of Biomedical Sciences, Institute of Health and Biomedical Innovation, QUT, Musk Ave, Kelvin Grove, QLD, 4059, Australia
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48
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Soga K, Ishikawa K, Furuya T, Iida T, Yamada T, Ando N, Ota K, Kanno-Okada H, Tanaka S, Shintaku M, Eishi Y, Mizusawa H, Yokota T. Gene dosage effect in spinocerebellar ataxia type 6 homozygotes: A clinical and neuropathological study. J Neurol Sci 2016; 373:321-328. [PMID: 28131213 DOI: 10.1016/j.jns.2016.12.051] [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: 10/09/2016] [Revised: 12/20/2016] [Accepted: 12/23/2016] [Indexed: 02/07/2023]
Abstract
Spinocerebellar ataxia type 6 (SCA6) is an autosomal dominant neurodegenerative disorder. However, it remains unclear whether SCA6 shows a gene dosage effect, defined by earlier age-of-onset in homozygotes than heterozygotes. Herein, we retrospectively analyzed four homozygous SCA6 subjects from our single institution cohort of 120 SCA6 subjects. We also performed a neuropathological investigation into an SCA6 individual with compound heterozygous expansions. In the 116 heterozygotes, there was an inverse correlation of age-of-onset with the number of CAG repeats in the expanded allele, and with the total number of CAG repeats, in both normal and expanded alleles. The age-of-onset in the four homozygotes was within the 95% confidence interval of the age-of-onset versus the repeat-lengths correlations determined in the 116 heterozygotes. Nevertheless, all homozygotes had earlier onset than their parents, and showed rapid disease progression. Neuropathology revealed neuronal loss, as well as α1A-calcium channel protein aggregates in Purkinje cells, a few α1A-calcium channel protein aggregates in the neocortex and basal ganglia, and neuronal loss in Clarke's column and the globus pallidus not seen in heterozygotes. These data suggest a mild clinical and neuropathological gene dosage effect in SCA6 subjects.
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Affiliation(s)
- Kazumasa Soga
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Kinya Ishikawa
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan; The Center for Personalized Medicine for Healthy Aging, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
| | - Tokuro Furuya
- Department of Neurology, Kawaguchi Kogyo General Hospital, 1-18-15 Aoki, Kawaguchi, Saitama 332-0031, Japan
| | - Tadatsune Iida
- Department of Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan; Department of Cellular Neurobiology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tetsuo Yamada
- Department of Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan; Laboratory of Pathology, Department of Clinical Laboratory Medicine, Bunkyo Gakuin University Graduate School of Health Care Science, 2-4-1 Mukogaoka, Bunkyo-ku, Tokyo 113-0023, Japan
| | - Noboru Ando
- Department of Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Kiyobumi Ota
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Hiromi Kanno-Okada
- Department of Cancer Pathology, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo 060-8638, Hokkaido, Japan; Department of Surgical Pathology, Hokkaido University Hospital, Hokkaido University, North 14, West 5, Kita-ku, Sapporo 060-8648, Hokkaido, Japan
| | - Shinya Tanaka
- Department of Cancer Pathology, Hokkaido University Graduate School of Medicine, North 15, West 7, Kita-ku, Sapporo 060-8638, Hokkaido, Japan
| | - Masayuki Shintaku
- Department of Pathology, Shiga Medical Center for Adults, 5-4-30 Moriyama, Moriyama, Shiga 524-8524, Japan
| | - Yoshinobu Eishi
- Department of Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Hidehiro Mizusawa
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan; The National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Takanori Yokota
- Department of Neurology and Neurological Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
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49
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Ljungberg L, Lang-Ouellette D, Yang A, Jayabal S, Quilez S, Watt AJ. Transient Developmental Purkinje Cell Axonal Torpedoes in Healthy and Ataxic Mouse Cerebellum. Front Cell Neurosci 2016; 10:248. [PMID: 27853421 PMCID: PMC5089982 DOI: 10.3389/fncel.2016.00248] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 10/10/2016] [Indexed: 12/13/2022] Open
Abstract
Information is carried out of the cerebellar cortical microcircuit via action potentials propagated along Purkinje cell axons. In several human neurodegenerative diseases, focal axonal swellings on Purkinje cells – known as torpedoes – have been associated with Purkinje cell loss. Interestingly, torpedoes are also reported to appear transiently during development in rat cerebellum. The function of Purkinje cell axonal torpedoes in health as well as in disease is poorly understood. We investigated the properties of developmental torpedoes in the postnatal mouse cerebellum of wild-type and transgenic mice. We found that Purkinje cell axonal torpedoes transiently appeared on axons of Purkinje neurons, with the largest number of torpedoes observed at postnatal day 11 (P11). This was after peak developmental apoptosis had occurred, when Purkinje cell counts in a lobule were static, suggesting that most developmental torpedoes appear on axons of neurons that persist into adulthood. We found that developmental torpedoes were not associated with a presynaptic GABAergic marker, indicating that they are not synapses. They were seldom found at axonal collateral branch points, and lacked microglia enrichment, suggesting that they are unlikely to be involved in axonal refinement. Interestingly, we found several differences between developmental torpedoes and disease-related torpedoes: developmental torpedoes occurred largely on myelinated axons, and were not associated with changes in basket cell innervation on their parent soma. Disease-related torpedoes are typically reported to contain neurofilament; while the majority of developmental torpedoes did as well, a fraction of smaller developmental torpedoes did not. These differences indicate that developmental torpedoes may not be functionally identical to disease-related torpedoes. To study this further, we used a mouse model of spinocerebellar ataxia type 6 (SCA6), and found elevated disease-related torpedo number at 2 years. However, we found normal levels of developmental torpedoes in these mice. Our findings suggest that the transient emergence of Purkinje cell axonal torpedoes during the second postnatal week in mice represents a normal morphological feature in the developing cerebellar microcircuit.
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Affiliation(s)
| | | | - Angela Yang
- Department of Biology, McGill University, Montreal QC, Canada
| | - Sriram Jayabal
- Department of Biology, McGill University, Montreal QC, Canada
| | - Sabrina Quilez
- Department of Biology, McGill University, Montreal QC, Canada
| | - Alanna J Watt
- Department of Biology, McGill University, Montreal QC, Canada
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50
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Jayabal S, Ljungberg L, Watt AJ. Transient cerebellar alterations during development prior to obvious motor phenotype in a mouse model of spinocerebellar ataxia type 6. J Physiol 2016; 595:949-966. [PMID: 27531396 DOI: 10.1113/jp273184] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 08/12/2016] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Spinocerebellar ataxia type 6 (SCA6) is a midlife-onset neurodegenerative disease caused by a CACNA1A mutation; CACNA1A is also implicated in cerebellar development. We have previously shown that when disease symptoms are present in midlife in SCA684Q/84Q mice, cerebellar Purkinje cells spike with reduced rate and precision. In contrast, we find that during postnatal development (P10-13), SCA684Q/84Q Purkinje cells spike with elevated rate and precision. Although surplus climbing fibres are linked to ataxia in other mouse models, we found surplus climbing fibre inputs on developing (P10-13) SCA684Q/84Q Purkinje cells when motor deficits were not detected. Developmental alterations were transient and were no longer observed in weanling (P21-24) SCA684Q/84Q Purkinje cells. Our results suggest that changes in the developing cerebellar circuit can occur without detectable motor abnormalities, and that changes in cerebellar development may not necessarily persist into adulthood. ABSTRACT Although some neurodegenerative diseases are caused by mutations in genes that are known to regulate neuronal development, surprisingly, patients may not present disease symptoms until adulthood. Spinocerebellar ataxia type 6 (SCA6) is one such midlife-onset disorder in which the mutated gene, CACNA1A, is implicated in cerebellar development. We wondered whether changes were observed in the developing cerebellum in SCA6 prior to the detection of motor deficits. To address this question, we used a transgenic mouse with a hyper-expanded triplet repeat (SCA684Q/84Q ) that displays late-onset motor deficits at 7 months, and measured cerebellar Purkinje cell synaptic and intrinsic properties during postnatal development. We found that firing rate and precision were enhanced during postnatal development in P10-13 SCA684Q/84Q Purkinje cells, and observed surplus multiple climbing fibre innervation without changes in inhibitory input or dendritic structure during development. Although excess multiple climbing fibre innervation has been associated with ataxic symptoms in several adult transgenic mice, we observed no detectable changes in cerebellar-related motor behaviour in developing SCA684Q/84Q mice. Interestingly, we found that developmental alterations were transient, as both Purkinje cell firing properties and climbing fibre innervation from weanling-aged (P21-24) SCA684Q/84Q mice were indistinguishable from litter-matched control mice. Our results demonstrate that significant alterations in neuronal circuit development may be observed without any detectable behavioural read-out, and that early changes in brain development may not necessarily persist into adulthood in midlife-onset diseases.
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Affiliation(s)
- Sriram Jayabal
- Department of Biology, McGill University, Montreal, H3G 0B1, Canada.,Integrated Program in Neuroscience, McGill University, Montreal, H3G 0B1, Canada
| | - Lovisa Ljungberg
- Department of Biology, McGill University, Montreal, H3G 0B1, Canada
| | - Alanna J Watt
- Department of Biology, McGill University, Montreal, H3G 0B1, Canada
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