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Raghunathan N, Sankaran S, Miteu GD. A comprehensive review of iPS cell line-based disease modelling of the polyglutamine spinocerebellar ataxias 2 and 3: a focus on the research outcomes. Ann Med Surg (Lond) 2024; 86:3487-3498. [PMID: 38846892 PMCID: PMC11152827 DOI: 10.1097/ms9.0000000000001984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/07/2024] [Indexed: 06/09/2024] Open
Abstract
Spinocerebellar ataxias (SCAs) are a rare autosomal dominant neurodegenerative disorder. To date, approximately 50 different subtypes of SCAs have been characterized. The prevalent types of SCAs are usually of PolyQ origin, wherein the disease pathology is a consequence of multiple glutamine residues being encoded onto the disease proteins, causing expansions. SCAs 2 and 3 are the most frequently diagnosed subtypes, wherein affected patients exhibit certain characteristic physiological manifestations, such as gait ataxia and dysarthria. Nevertheless, other clinical signs were exclusive to these subtypes. Recently, multiple molecular diagnostic methods have been developed to identify and characterize these subtypes. Despite these advancements, the molecular pathology of SCAs remains unknown. To further understand the mechanisms involved in neurodegenerative SCAs 2 and 3, patient-derived induced pluripotent stem cell (iPSC)-based modelling is a compelling avenue to pursue. We cover the present state of iPSC-based in-vitro illness modelling of SCA subtypes 2 and 3 below, along with a list of cell lines created, and the relevance of research outcomes to personalized autologous therapy.
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Affiliation(s)
| | | | - Goshen D. Miteu
- School of Biosciences, Biotechnology, University of Nottingham, England, UK
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, North Dakota, USA
- Department of Biochemistry, Caleb University, Lagos, Nigeria
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2
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Watchon M, Robinson KJ, Luu L, An Y, Yuan KC, Plenderleith SK, Cheng F, Don EK, Nicholson GA, Lee A, Laird AS. Treatment with sodium butyrate induces autophagy resulting in therapeutic benefits for spinocerebellar ataxia type 3. FASEB J 2024; 38:e23429. [PMID: 38258931 DOI: 10.1096/fj.202300963rr] [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: 05/12/2023] [Revised: 12/21/2023] [Accepted: 01/03/2024] [Indexed: 01/24/2024]
Abstract
Spinocerebellar ataxia type 3 (SCA3, also known as Machado Joseph disease) is a fatal neurodegenerative disease caused by the expansion of the trinucleotide repeat region within the ATXN3/MJD gene. Mutation of ATXN3 causes formation of ataxin-3 protein aggregates, neurodegeneration, and motor deficits. Here we investigated the therapeutic potential and mechanistic activity of sodium butyrate (SB), the sodium salt of butyric acid, a metabolite naturally produced by gut microbiota, on cultured SH-SY5Y cells and transgenic zebrafish expressing human ataxin-3 containing 84 glutamine (Q) residues to model SCA3. SCA3 SH-SY5Y cells were found to contain high molecular weight ataxin-3 species and detergent-insoluble protein aggregates. Treatment with SB increased the activity of the autophagy protein quality control pathway in the SCA3 cells, decreased the presence of ataxin-3 aggregates and presence of high molecular weight ataxin-3 in an autophagy-dependent manner. Treatment with SB was also beneficial in vivo, improving swimming performance, increasing activity of the autophagy pathway, and decreasing the presence of insoluble ataxin-3 protein species in the transgenic SCA3 zebrafish. Co-treating the SCA3 zebrafish with SB and chloroquine, an autophagy inhibitor, prevented the beneficial effects of SB on zebrafish swimming, indicating that the improved swimming performance was autophagy-dependent. To understand the mechanism by which SB induces autophagy we performed proteomic analysis of protein lysates from the SB-treated and untreated SCA3 SH-SY5Y cells. We found that SB treatment had increased activity of Protein Kinase A and AMPK signaling, with immunoblot analysis confirming that SB treatment had increased levels of AMPK protein and its substrates. Together our findings indicate that treatment with SB can increase activity of the autophagy pathway process and that this has beneficial effects in vitro and in vivo. While our results suggested that this activity may involve activity of a PKA/AMPK-dependent process, this requires further confirmation. We propose that treatment with sodium butyrate warrants further investigation as a potential treatment for neurodegenerative diseases underpinned by mechanisms relating to protein aggregation including SCA3.
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Affiliation(s)
- Maxinne Watchon
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Katherine J Robinson
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Luan Luu
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Yousun An
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Kristy C Yuan
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Stuart K Plenderleith
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Flora Cheng
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Emily K Don
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Garth A Nicholson
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
- ANZAC Research Institute, Concord Repatriation Hospital, Concord, New South Wales, Australia
| | - Albert Lee
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Angela S Laird
- Motor Neuron Disease Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, New South Wales, Australia
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Autophagy Function and Benefits of Autophagy Induction in Models of Spinocerebellar Ataxia Type 3. Cells 2023; 12:cells12060893. [PMID: 36980234 PMCID: PMC10047838 DOI: 10.3390/cells12060893] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/20/2023] [Accepted: 03/07/2023] [Indexed: 03/17/2023] Open
Abstract
Background: Spinocerebellar ataxia 3 (SCA3, also known as Machado Joseph disease) is a fatal neurodegenerative disease caused by the expansion of the trinucleotide repeat region within the ATXN3/MJD gene. The presence of this genetic expansion results in an ataxin-3 protein containing a polyglutamine repeat region, which renders the ataxin-3 protein aggregation prone. Formation of ataxin-3 protein aggregates is linked with neuronal loss and, therefore, the development of motor deficits. Methods: Here, we investigated whether the autophagy protein quality control pathway, which is important in the process of protein aggregate removal, is impaired in a cell culture and zebrafish model of SCA3. Results: We found that SH-SY5Y cells expressing human ataxin-3 containing polyglutamine expansion exhibited aberrant levels of autophagy substrates, including increased p62 and decreased LC3II (following bafilomycin treatment), compared to the controls. Similarly, transgenic SCA3 zebrafish showed signs of autophagy impairment at early disease stages (larval), as well as p62 accumulation at advanced age stages (18 months old). We then examined whether treating with compounds known to induce autophagy activity, would aid removal of human ataxin-3 84Q and improve the swimming of the SCA3 zebrafish larvae. We found that treatment with loperamide, trehalose, rapamycin, and MG132 each improved the swimming of the SCA3 zebrafish compared to the vehicle-treated controls. Conclusion: We propose that signs of autophagy impairment occur in the SH-SY5Y model of SCA3 and SCA3 zebrafish at larval and advanced age stages. Treatment of the larval SCA3 zebrafish with various compounds with autophagy induction capacity was able to produce the improved swimming of the zebrafish, suggesting the potential benefit of autophagy-inducing compounds for the treatment of SCA3.
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Hauser S, Helm J, Kraft M, Korneck M, Hübener-Schmid J, Schöls L. Allele-specific targeting of mutant ataxin-3 by antisense oligonucleotides in SCA3-iPSC-derived neurons. MOLECULAR THERAPY. NUCLEIC ACIDS 2022; 27:99-108. [PMID: 34938609 PMCID: PMC8649108 DOI: 10.1016/j.omtn.2021.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 11/16/2021] [Indexed: 12/01/2022]
Abstract
Spinocerebellar ataxia type 3 (SCA3) is caused by an expanded polyglutamine stretch in ataxin-3. While wild-type ataxin-3 has important functions, e.g., as a deubiquitinase, downregulation of mutant ataxin-3 is likely to slow down the course of this fatal disease. We established a screening platform with human neurons of patients and controls derived from induced pluripotent stem cells to test antisense oligonucleotides (ASOs) for their effects on ataxin-3 expression. We identified an ASO that suppressed mutant and wild-type ataxin-3 levels by >90% after a singular treatment. Next, we screened pairs of ASOs designed to selectively target the mutant or the wild-type allele by taking advantage of a SNP (c.987G > C) in ATXN3 that is present in most SCA3 patients. We found ASOmut4 to reduce levels of mutant ataxin-3 by 80% after 10 days while leaving expression of wild-type ataxin-3 largely unaffected. In a long-term study we proved this effect to last for about 4 weeks after a single treatment without signs of neurotoxicity. This study provides proof of principle that allele-specific lowering of poly(Q)-expanded ataxin-3 by selective ASOs is feasible and long lasting, with sparing of wild-type ataxin-3 expression in a human cell culture model that is genetically identical to SCA3 patients.
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Affiliation(s)
- Stefan Hauser
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany.,Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
| | - Jacob Helm
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany.,Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany.,Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Melanie Kraft
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany.,Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
| | - Milena Korneck
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany.,Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany.,Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Jeannette Hübener-Schmid
- Institute of Medical Genetics and Applied Genomics and Center of Rare Diseases, University of Tübingen, 72076 Tübingen, Germany
| | - Ludger Schöls
- German Center for Neurodegenerative Diseases (DZNE), 72076 Tübingen, Germany.,Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany
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5
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Hou PS, Kuo HC. Central nervous system organoids for modeling neurodegenerative diseases. IUBMB Life 2022; 74:812-825. [PMID: 35102668 DOI: 10.1002/iub.2595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/18/2021] [Accepted: 12/02/2021] [Indexed: 11/07/2022]
Abstract
Recent advances in induced pluripotent stem cell (iPSC) technology have allowed researchers to generate neurodegenerative disease-specific iPSCs and use the cells to derive a variety of relevant cell populations for laboratory modeling and drug testing. Nevertheless, these efforts have faced challenges related to immaturity and lack of complex developmental niches in the derived cell populations, limiting the utility of these in vitro models of neurodegenerative disease. Such limitations may be overcome by using human iPSC technology to generate three-dimensional (3D) brain organoids, which better recapitulate in vivo tissue architecture than traditional neuronal cultures to provide more complex and representative disease models and drug testing systems. In this review, we focus on the application of pluripotent stem cell-derived central nervous system (CNS) organoids to model neurodegenerative diseases. We first summarize recent progress in generating and characterizing various CNS organoids from pluripotent stem cells. We then review the application of CNS organoids for modeling several different human neurodegenerative diseases. We also describe several novel pathological mechanisms and drugs that were studied using patient iPSC-derived CNS organoids. Finally, we discuss remaining challenges and emerging opportunities for the use of 3D brain organoids for in vitro modeling of CNS development and neurodegeneration.
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Affiliation(s)
- Pei-Shan Hou
- Institute of Anatomy and Cell Biology, National Yang-Ming Chiao-Tung University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming Chiao-Tung University, Taipei, Taiwan
| | - Hung-Chih Kuo
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.,Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei, Taiwan
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Patient-Specific iPSCs-Based Models of Neurodegenerative Diseases: Focus on Aberrant Calcium Signaling. Int J Mol Sci 2022; 23:ijms23020624. [PMID: 35054808 PMCID: PMC8776084 DOI: 10.3390/ijms23020624] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 02/04/2023] Open
Abstract
The development of cell reprogramming technologies became a breakthrough in the creation of new models of human diseases, including neurodegenerative pathologies. The iPSCs-based models allow for the studying of both hereditary and sporadic cases of pathologies and produce deep insight into the molecular mechanisms underlying neurodegeneration. The use of the cells most vulnerable to a particular pathology makes it possible to identify specific pathological mechanisms and greatly facilitates the task of selecting the most effective drugs. To date, a large number of studies on patient-specific models of neurodegenerative diseases has been accumulated. In this review, we focused on the alterations of such a ubiquitous and important intracellular regulatory pathway as calcium signaling. Here, we reviewed and analyzed the data obtained from iPSCs-based models of different neurodegenerative disorders that demonstrated aberrant calcium signaling.
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Tzou FY, Wen JK, Yeh JY, Huang SY, Chen GC, Chan CC. Drosophila as a model to study autophagy in neurodegenerative diseases and digestive tract. IUBMB Life 2021; 74:339-360. [PMID: 34874101 DOI: 10.1002/iub.2583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/08/2021] [Accepted: 11/15/2021] [Indexed: 12/20/2022]
Abstract
Autophagy regulates cellular homeostasis by degrading and recycling cytosolic components and damaged organelles. Disruption of autophagic flux has been shown to induce or facilitate neurodegeneration and accumulation of autophagic vesicles is overt in neurodegenerative diseases. The fruit fly Drosophila has been used as a model system to identify new factors that regulate physiology and disease. Here we provide a historical perspective of how the fly models have offered mechanistic evidence to understand the role of autophagy in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Charcot-Marie-Tooth neuropathy, and polyglutamine disorders. Autophagy also plays a pivotal role in maintaining tissue homeostasis and protecting organism health. The gastrointestinal tract regulates organism health by modulating food intake, energy balance, and immunity. Growing evidence is strengthening the link between autophagy and digestive tract health in recent years. Here, we also discuss how the fly models have advanced the understanding of digestive physiology regulated by autophagy.
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Affiliation(s)
- Fei-Yang Tzou
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Jung-Kun Wen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Jui-Yu Yeh
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Shu-Yi Huang
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Guang-Chao Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Chih-Chiang Chan
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
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8
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Pathophysiological interplay between O-GlcNAc transferase and the Machado-Joseph disease protein ataxin-3. Proc Natl Acad Sci U S A 2021; 118:2025810118. [PMID: 34785590 DOI: 10.1073/pnas.2025810118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2021] [Indexed: 11/18/2022] Open
Abstract
Aberrant O-GlcNAcylation, a protein posttranslational modification defined by the O-linked attachment of the monosaccharide N-acetylglucosamine (O-GlcNAc), has been implicated in neurodegenerative diseases. However, although many neuronal proteins are substrates for O-GlcNAcylation, this process has not been extensively investigated in polyglutamine disorders. We aimed to evaluate the enzyme O-GlcNAc transferase (OGT), which attaches O-GlcNAc to target proteins, in Machado-Joseph disease (MJD). MJD is a neurodegenerative condition characterized by ataxia and caused by the expansion of a polyglutamine stretch within the deubiquitinase ataxin-3, which then present increased propensity to aggregate. By analyzing MJD cell and animal models, we provide evidence that OGT is dysregulated in MJD, therefore compromising the O-GlcNAc cycle. Moreover, we demonstrate that wild-type ataxin-3 modulates OGT protein levels in a proteasome-dependent manner, and we present OGT as a substrate for ataxin-3. Targeting OGT levels and activity reduced ataxin-3 aggregates, improved protein clearance and cell viability, and alleviated motor impairment reminiscent of ataxia of MJD patients in zebrafish model of the disease. Taken together, our results point to a direct interaction between OGT and ataxin-3 in health and disease and propose the O-GlcNAc cycle as a promising target for the development of therapeutics in the yet incurable MJD.
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9
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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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He L, Chen Z, Peng L, Tang B, Jiang H. Human stem cell models of polyglutamine diseases: Sources for disease models and cell therapy. Exp Neurol 2020; 337:113573. [PMID: 33347831 DOI: 10.1016/j.expneurol.2020.113573] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 12/19/2022]
Abstract
Polyglutamine (polyQ) diseases are a group of neurodegenerative disorders involving expanded CAG repeats in pathogenic genes that are translated into extended polyQ tracts and lead to progressive neuronal degeneration in the affected brain. To date, there is no effective therapy for these diseases. Due to the complex pathologic mechanisms of these diseases, intensive research on the pathogenesis of their progression and potential treatment strategies is being conducted. However, animal models cannot recapitulate all aspects of neuronal degeneration. Pluripotent stem cells (PSCs), such as induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs), can be used to study the pathological mechanisms of polyQ diseases, and the ability of autologous stem cell transplantation to treat these diseases. Differentiated PSCs, neuronal precursor cells/neural progenitor cells (NPCs) and mesenchymal stem cells (MSCs) are valuable resources for preclinical and clinical cell transplantation therapies. Here, we discuss diverse stem cell models and their ability to generate neurons involved in polyQ diseases, such as medium spiny neurons (MSNs), cortical neurons, cerebellar Purkinje cells (PCs) and motor neurons. In addition, we discuss potential therapeutic approaches, including stem cell replacement therapy and gene therapy.
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Affiliation(s)
- Lang He
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhao Chen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China; National Clinical Research Center for Geriatric Diseases, Central South University, Changsha, Hunan, China
| | - Linliu Peng
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Beisha Tang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China; National Clinical Research Center for Geriatric Diseases, Central South University, Changsha, Hunan, China; Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China
| | - Hong Jiang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China; Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, Hunan, China; National Clinical Research Center for Geriatric Diseases, Central South University, Changsha, Hunan, China; Laboratory of Medical Genetics, Central South University, Changsha, Hunan, China.
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11
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The Role of iPSC Modeling Toward Projection of Autophagy Pathway in Disease Pathogenesis: Leader or Follower. Stem Cell Rev Rep 2020; 17:539-561. [PMID: 33245492 DOI: 10.1007/s12015-020-10077-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2020] [Indexed: 12/12/2022]
Abstract
Autophagy is responsible for degradation of non-essential or damaged cellular constituents and damaged organelles. The autophagy pathway maintains efficient cellular metabolism and reduces cellular stress by removing additional and pathogenic components. Dysfunctional autophagy underlies several diseases. Thus, several research groups have worked toward elucidating key steps in this pathway. Autophagy can be studied by animal modeling, chemical modulators, and in vitro disease modeling with induced pluripotent stem cells (iPSC) as a loss-of-function platform. The introduction of iPSC technology, which has the capability to maintain the genetic background, has facilitated in vitro modeling of some diseases. Furthermore, iPSC technology can be used as a platform to study defective cellular and molecular pathways during development and unravel novel steps in signaling pathways of health and disease. Different studies have used iPSC technology to explore the role of autophagy in disease pathogenesis which could not have been addressed by animal modeling or chemical inducers/inhibitors. In this review, we discuss iPSC models of autophagy-associated disorders where the disease is caused due to mutations in autophagy-related genes. We classified this group as "primary autophagy induced defects (PAID)". There are iPSC models of diseases in which the primary cause is not dysfunctional autophagy, but autophagy is impaired secondary to disease phenotypes. We call this group "secondary autophagy induced defects (SAID)" and discuss them. Graphical abstract.
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12
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Investigating developmental and disease mechanisms of the cerebellum with pluripotent stem cells. Mol Cell Neurosci 2020; 107:103530. [PMID: 32693017 DOI: 10.1016/j.mcn.2020.103530] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/15/2020] [Accepted: 07/15/2020] [Indexed: 01/02/2023] Open
Abstract
The cerebellum is a brain region located in the dorsal part of the anterior hindbrain, composed of a highly stereotyped neural circuit structure with small sets of neurons. The cerebellum is involved in a wide variety of functions such as motor control, learning, cognition and others. Damage to the cerebellum often leads to impairments in motor skills (cerebellar ataxia). Cerebellar ataxia can occur as a result of neurodegenerative diseases such as spinocerebellar ataxia. Recent advances in technologies related to pluripotent stem cells and their neural differentiation has enabled researchers to investigate the mechanisms of development and of disease in the human brain. Here, we review recent applications of leading-edge stem cell technologies to the mechanistic investigation of human cerebellar development and neurological diseases affecting the cerebellum.
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13
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Lee D, Lee YI, Lee YS, Lee SB. The Mechanisms of Nuclear Proteotoxicity in Polyglutamine Spinocerebellar Ataxias. Front Neurosci 2020; 14:489. [PMID: 32581673 PMCID: PMC7289180 DOI: 10.3389/fnins.2020.00489] [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: 02/22/2020] [Accepted: 04/20/2020] [Indexed: 12/29/2022] Open
Abstract
Polyglutamine (polyQ) spinocerebellar ataxias (SCAs) are the most prevalent subset of SCAs and share the aberrant expansion of Q-encoding CAG repeats within the coding sequences of disease-responsible genes as their common genetic cause. These polyQ SCAs (SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17) are inherited neurodegenerative diseases characterized by the progressive atrophy of the cerebellum and connected regions of the nervous system, which leads to loss of fine muscle movement coordination. Upon the expansion of polyQ repeats, the mutated proteins typically accumulate disproportionately in the neuronal nucleus, where they sequester various target molecules, including transcription factors and other nuclear proteins. However, it is not yet clearly understood how CAG repeat expansion takes place or how expanded polyQ proteins accumulate in the nucleus. In this article, we review the current knowledge on the molecular and cellular bases of nuclear proteotoxicity of polyQ proteins in SCAs and present our perspectives on the remaining issues surrounding these diseases.
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Affiliation(s)
- Davin Lee
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
| | - Yun-Il Lee
- Well Aging Research Center, Division of Biotechnology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Young-Sam Lee
- Well Aging Research Center, Division of Biotechnology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea.,Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Sung Bae Lee
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, South Korea
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Chen YS, Hong ZX, Lin SZ, Harn HJ. Identifying Therapeutic Targets for Spinocerebellar Ataxia Type 3/Machado-Joseph Disease through Integration of Pathological Biomarkers and Therapeutic Strategies. Int J Mol Sci 2020; 21:ijms21093063. [PMID: 32357546 PMCID: PMC7246822 DOI: 10.3390/ijms21093063] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 04/21/2020] [Accepted: 04/24/2020] [Indexed: 12/13/2022] Open
Abstract
Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is a progressive motor disease with no broadly effective treatment. However, most current therapies are based on symptoms rather than the underlying disease mechanisms. In this review, we describe potential therapeutic strategies based on known pathological biomarkers and related pathogenic processes. The three major conclusions from the current studies are summarized as follows: (i) for the drugs currently being tested in clinical trials; a weak connection was observed between drugs and SCA3/MJD biomarkers. The only two exceptions are the drugs suppressing glutamate-induced calcium influx and chemical chaperon. (ii) For most of the drugs that have been tested in animal studies, there is a direct association with pathological biomarkers. We further found that many drugs are associated with inducing autophagy, which is supported by the evidence of deficient autophagy biomarkers in SCA3/MJD, and that there may be more promising therapeutics. (iii) Some reported biomarkers lack relatively targeted drugs. Low glucose utilization, altered amino acid metabolism, and deficient insulin signaling are all implicated in SCA3/MJD, but there have been few studies on treatment strategies targeting these abnormalities. Therapeutic strategies targeting multiple pathological SCA3/MJD biomarkers may effectively block disease progression and preserve neurological function.
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Affiliation(s)
- Yu-Shuan Chen
- Bioinnovation Center, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
- Department of Medical Research, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
- Correspondence: (Y.-S.C.); (H.-J.H.); Tel.: +886-3-856-1825 (Y.-S.C. & H.-J.H.); Fax: +886-3-856-0977 (H.-J.H.)
| | - Zhen-Xiang Hong
- Bioinnovation Center, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
| | - Shinn-Zong Lin
- Bioinnovation Center, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
- Department of Neurosurgery, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
| | - Horng-Jyh Harn
- Bioinnovation Center, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
- Department of Pathology, Hualien Tzu Chi Hospital, Tzu Chi University, Buddhist Tzu Chi Medical Foundation, Hualien 97002, Taiwan
- Correspondence: (Y.-S.C.); (H.-J.H.); Tel.: +886-3-856-1825 (Y.-S.C. & H.-J.H.); Fax: +886-3-856-0977 (H.-J.H.)
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15
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Induced Pluripotent Stem Cell (iPSC)-Based Neurodegenerative Disease Models for Phenotype Recapitulation and Drug Screening. Molecules 2020; 25:molecules25082000. [PMID: 32344649 PMCID: PMC7221979 DOI: 10.3390/molecules25082000] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases represent a significant unmet medical need in our aging society. There are no effective treatments for most of these diseases, and we know comparatively little regarding pathogenic mechanisms. Among the challenges faced by those involved in developing therapeutic drugs for neurodegenerative diseases, the syndromes are often complex, and small animal models do not fully recapitulate the unique features of the human nervous system. Human induced pluripotent stem cells (iPSCs) are a novel technology that ideally would permit us to generate neuronal cells from individual patients, thereby eliminating the problem of species-specificity inherent when using animal models. Specific phenotypes of iPSC-derived cells may permit researchers to identify sub-types and to distinguish among unique clusters and groups. Recently, iPSCs were used for drug screening and testing for neurologic disorders including Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), spinocerebellar atrophy (SCA), and Zika virus infection. However, there remain many challenges still ahead, including how one might effectively recapitulate sporadic disease phenotypes and the selection of ideal phenotypes and for large-scale drug screening. Fortunately, quite a few novel strategies have been developed that might be combined with an iPSC-based model to solve these challenges, including organoid technology, single-cell RNA sequencing, genome editing, and deep learning artificial intelligence. Here, we will review current applications and potential future directions for iPSC-based neurodegenerative disease models for critical drug screening.
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Seranova E, Palhegyi AM, Verma S, Dimova S, Lasry R, Naama M, Sun C, Barrett T, Rosenstock TR, Kumar D, Cohen MA, Buganim Y, Sarkar S. Human Induced Pluripotent Stem Cell Models of Neurodegenerative Disorders for Studying the Biomedical Implications of Autophagy. J Mol Biol 2020; 432:2754-2798. [PMID: 32044344 DOI: 10.1016/j.jmb.2020.01.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 12/12/2022]
Abstract
Autophagy is an intracellular degradation process that is essential for cellular survival, tissue homeostasis, and human health. The housekeeping functions of autophagy in mediating the clearance of aggregation-prone proteins and damaged organelles are vital for post-mitotic neurons. Improper functioning of this process contributes to the pathology of myriad human diseases, including neurodegeneration. Impairment in autophagy has been reported in several neurodegenerative diseases where pharmacological induction of autophagy has therapeutic benefits in cellular and transgenic animal models. However, emerging studies suggest that the efficacy of autophagy inducers, as well as the nature of the autophagy defects, may be context-dependent, and therefore, studies in disease-relevant experimental systems may provide more insights for clinical translation to patients. With the advancements in human stem cell technology, it is now possible to establish disease-affected cellular platforms from patients for investigating disease mechanisms and identifying candidate drugs in the appropriate cell types, such as neurons that are otherwise not accessible. Towards this, patient-derived human induced pluripotent stem cells (hiPSCs) have demonstrated considerable promise in constituting a platform for effective disease modeling and drug discovery. Multiple studies have utilized hiPSC models of neurodegenerative diseases to study autophagy and evaluate the therapeutic efficacy of autophagy inducers in neuronal cells. This review provides an overview of the regulation of autophagy, generation of hiPSCs via cellular reprogramming, and neuronal differentiation. It outlines the findings in various neurodegenerative disorders where autophagy has been studied using hiPSC models.
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Affiliation(s)
- Elena Seranova
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Adina Maria Palhegyi
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Surbhi Verma
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom; Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Simona Dimova
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Rachel Lasry
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University Hadassah Medical School, Jerusalem, 91120, Israel
| | - Moriyah Naama
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University Hadassah Medical School, Jerusalem, 91120, Israel
| | - Congxin Sun
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Timothy Barrett
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Tatiana Rosado Rosenstock
- Department of Physiological Science, Santa Casa de São Paulo School of Medical Sciences, São Paulo, SP, 01221-020, Brazil
| | - Dhiraj Kumar
- Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Malkiel A Cohen
- Whitehead Institute for Biomedical Research, Cambridge, MA, 02142, USA
| | - Yosef Buganim
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University Hadassah Medical School, Jerusalem, 91120, Israel
| | - Sovan Sarkar
- Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
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17
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McLoughlin HS, Moore LR, Paulson HL. Pathogenesis of SCA3 and implications for other polyglutamine diseases. Neurobiol Dis 2019; 134:104635. [PMID: 31669734 DOI: 10.1016/j.nbd.2019.104635] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 09/30/2019] [Accepted: 10/03/2019] [Indexed: 12/14/2022] Open
Abstract
Tandem repeat diseases include the neurodegenerative disorders known as polyglutamine (polyQ) diseases, caused by CAG repeat expansions in the coding regions of the respective disease genes. The nine known polyQ disease include Huntington's disease (HD), dentatorubral-pallidoluysian atrophy (DRPLA), spinal bulbar muscular atrophy (SBMA), and six spinocerebellar ataxias (SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17). The underlying disease mechanism in the polyQ diseases is thought principally to reflect dominant toxic properties of the disease proteins which, when harboring a polyQ expansion, differentially interact with protein partners and are prone to aggregate. Among the polyQ diseases, SCA3 is the most common SCA, and second to HD in prevalence worldwide. Here we summarize current understanding of SCA3 disease mechanisms within the broader context of the broader polyQ disease field. We emphasize properties of the disease protein, ATXN3, and new discoveries regarding three potential pathogenic mechanisms: 1) altered protein homeostasis; 2) DNA damage and dysfunctional DNA repair; and 3) nonneuronal contributions to disease. We conclude with an overview of the therapeutic implications of recent mechanistic insights.
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Affiliation(s)
| | - Lauren R Moore
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Henry L Paulson
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.
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Pueraria lobata and Daidzein Reduce Cytotoxicity by Enhancing Ubiquitin-Proteasome System Function in SCA3-iPSC-Derived Neurons. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:8130481. [PMID: 31687087 PMCID: PMC6800904 DOI: 10.1155/2019/8130481] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/07/2019] [Accepted: 07/23/2019] [Indexed: 12/27/2022]
Abstract
Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disorder caused by a CAG repeat expansion within the ATXN3/MJD1 gene. The expanded CAG repeats encode a polyglutamine (polyQ) tract at the C-terminus of the ATXN3 protein. ATXN3 containing expanded polyQ forms aggregates, leading to subsequent cellular dysfunctions including an impaired ubiquitin-proteasome system (UPS). To investigate the pathogenesis of SCA3 and develop potential therapeutic strategies, we established induced pluripotent stem cell (iPSC) lines from SCA3 patients (SCA3-iPSC). Neurons derived from SCA3-iPSCs formed aggregates that are positive to the polyQ marker 1C2. Treatment with the proteasome inhibitor, MG132, on SCA3-iPSC-derived neurons downregulated proteasome activity, increased production of radical oxygen species (ROS), and upregulated the cleaved caspase 3 level and caspase 3 activity. This increased susceptibility to the proteasome inhibitor can be rescued by a Chinese herbal medicine (CHM) extract NH037 (from Pueraria lobata) and its constituent daidzein via upregulating proteasome activity and reducing protein ubiquitination, oxidative stress, cleaved caspase 3 level, and caspase 3 activity. Our results successfully recapitulate the key phenotypes of the neurons derived from SCA3 patients, as well as indicate the potential of NH037 and daidzein in the treatment for SCA3 patients.
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Naphade S, Tshilenge KT, Ellerby LM. Modeling Polyglutamine Expansion Diseases with Induced Pluripotent Stem Cells. Neurotherapeutics 2019; 16:979-998. [PMID: 31792895 PMCID: PMC6985408 DOI: 10.1007/s13311-019-00810-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Polyglutamine expansion disorders, which include Huntington's disease, have expanded CAG repeats that result in polyglutamine expansions in affected proteins. How this specific feature leads to distinct neuropathies in 11 different diseases is a fascinating area of investigation. Most proteins affected by polyglutamine expansions are ubiquitously expressed, yet their mechanisms of selective neurotoxicity are unknown. Induced pluripotent stem cells have emerged as a valuable tool to model diseases, understand molecular mechanisms, and generate relevant human neural and glia subtypes, cocultures, and organoids. Ideally, this tool will generate specific neuronal populations that faithfully recapitulate specific polyglutamine expansion disorder phenotypes and mimic the selective vulnerability of a given disease. Here, we review how induced pluripotent technology is used to understand the effects of the disease-causing polyglutamine protein on cell function, identify new therapeutic targets, and determine how polyglutamine expansion affects human neurodevelopment and disease. We will discuss ongoing challenges and limitations in our use of induced pluripotent stem cells to model polyglutamine expansion diseases.
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Affiliation(s)
- Swati Naphade
- Buck Institute for Research on Aging, 8001 Redwood Blvd, Novato, CA, 94945, USA
| | | | - Lisa M Ellerby
- Buck Institute for Research on Aging, 8001 Redwood Blvd, Novato, CA, 94945, USA.
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20
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Antisense oligonucleotide therapy rescues aggresome formation in a novel spinocerebellar ataxia type 3 human embryonic stem cell line. Stem Cell Res 2019; 39:101504. [PMID: 31374463 DOI: 10.1016/j.scr.2019.101504] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/11/2019] [Accepted: 07/15/2019] [Indexed: 01/01/2023] Open
Abstract
Spinocerebellar ataxia type 3 (SCA3) is a fatal, late-onset neurodegenerative disorder characterized by selective neuropathology in the brainstem, cerebellum, spinal cord, and substantia nigra. Here we report the first NIH-approved human embryonic stem cell (hESC) line derived from an embryo harboring the SCA3 mutation. Referred to as SCA3-hESC, this line is heterozygous for the mutant polyglutamine-encoding CAG repeat expansion in the ATXN3 gene. We observed relevant molecular hallmarks of the human disease at all differentiation stages from stem cells to cortical neurons, including robust ATXN3 aggregation and altered expression of key components of the protein quality control machinery. In addition, SCA3-hESCs exhibit nuclear accumulation of mutant ATXN3 and form p62-positive aggresomes. Finally, antisense oligonucleotide-mediated reduction of ATXN3 markedly suppressed aggresome formation. The SCA3-hESC line offers a unique and highly relevant human disease model that holds strong potential to advance understanding of SCA3 disease mechanisms and facilitate the evaluation of candidate therapies for SCA3.
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21
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Abstract
The spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of autosomal dominantly inherited progressive disorders, the clinical hallmark of which is loss of balance and coordination accompanied by slurred speech; onset is most often in adult life. Genetically, SCAs are grouped as repeat expansion SCAs, such as SCA3/Machado-Joseph disease (MJD), and rare SCAs that are caused by non-repeat mutations, such as SCA5. Most SCA mutations cause prominent damage to cerebellar Purkinje neurons with consecutive cerebellar atrophy, although Purkinje neurons are only mildly affected in some SCAs. Furthermore, other parts of the nervous system, such as the spinal cord, basal ganglia and pontine nuclei in the brainstem, can be involved. As there is currently no treatment to slow or halt SCAs (many SCAs lead to premature death), the clinical care of patients with SCA focuses on managing the symptoms through physiotherapy, occupational therapy and speech therapy. Intense research has greatly expanded our understanding of the pathobiology of many SCAs, revealing that they occur via interrelated mechanisms (including proteotoxicity, RNA toxicity and ion channel dysfunction), and has led to the identification of new targets for treatment development. However, the development of effective therapies is hampered by the heterogeneity of the SCAs; specific therapeutic approaches may be required for each disease.
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22
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Buijsen RAM, Toonen LJA, Gardiner SL, van Roon-Mom WMC. Genetics, Mechanisms, and Therapeutic Progress in Polyglutamine Spinocerebellar Ataxias. Neurotherapeutics 2019; 16:263-286. [PMID: 30607747 PMCID: PMC6554265 DOI: 10.1007/s13311-018-00696-y] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Autosomal dominant cerebellar ataxias (ADCAs) are a group of neurodegenerative disorders characterized by degeneration of the cerebellum and its connections. All ADCAs have progressive ataxia as their main clinical feature, frequently accompanied by dysarthria and oculomotor deficits. The most common spinocerebellar ataxias (SCAs) are 6 polyglutamine (polyQ) SCAs. These diseases are all caused by a CAG repeat expansion in the coding region of a gene. Currently, no curative treatment is available for any of the polyQ SCAs, but increasing knowledge on the genetics and the pathological mechanisms of these polyQ SCAs has provided promising therapeutic targets to potentially slow disease progression. Potential treatments can be divided into pharmacological and gene therapies that target the toxic downstream effects, gene therapies that target the polyQ SCA genes, and stem cell replacement therapies. Here, we will provide a review on the genetics, mechanisms, and therapeutic progress in polyglutamine spinocerebellar ataxias.
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Affiliation(s)
- Ronald A M Buijsen
- Department of Human Genetics, LUMC, P.O. Box 9600, 2300 RC, Leiden, The Netherlands.
| | - Lodewijk J A Toonen
- Department of Human Genetics, LUMC, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
| | - Sarah L Gardiner
- Department of Human Genetics, LUMC, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
- Department of Neurology, LUMC, P.O. Box 9600, 2300 RC, Leiden, The Netherlands
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23
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Xu S, Sui S, Zhang X, Pang B, Wan L, Pang D. Modulation of autophagy in human diseases strategies to foster strengths and circumvent weaknesses. Med Res Rev 2019; 39:1953-1999. [PMID: 30820989 DOI: 10.1002/med.21571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/20/2019] [Accepted: 02/05/2019] [Indexed: 12/19/2022]
Abstract
Autophagy is central to the maintenance of intracellular homeostasis across species. Accordingly, autophagy disorders are linked to a variety of diseases from the embryonic stage until death, and the role of autophagy as a therapeutic target has been widely recognized. However, autophagy-associated therapy for human diseases is still in its infancy and is supported by limited evidence. In this review, we summarize the landscape of autophagy-associated diseases and current autophagy modulators. Furthermore, we investigate the existing autophagy-associated clinical trials, analyze the obstacles that limit their progress, offer tactics that may allow barriers to be overcome along the way and then discuss the therapeutic potential of autophagy modulators in clinical applications.
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Affiliation(s)
- Shouping Xu
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Shiyao Sui
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Xianyu Zhang
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Boran Pang
- Department of Surgery, Rui Jin Hospital, Shanghai Key Laboratory of Gastric Neoplasm, Shanghai Institute of Digestive Surgery, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lin Wan
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Da Pang
- Department of Breast Surgery, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
- Heilongjiang Academy of Medical Sciences, Harbin, Heilongjcontrary, induction of autophagy elongiang, China
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24
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Osinalde N, Duarri A, Ramirez J, Barrio R, Perez de Nanclares G, Mayor U. Impaired proteostasis in rare neurological diseases. Semin Cell Dev Biol 2018; 93:164-177. [PMID: 30355526 DOI: 10.1016/j.semcdb.2018.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 10/09/2018] [Accepted: 10/16/2018] [Indexed: 12/19/2022]
Abstract
Rare diseases are classified as such when their prevalence is 1:2000 or lower, but even if each of them is so infrequent, altogether more than 300 million people in the world suffer one of the ∼7000 diseases considered as rare. Over 1200 of these disorders are known to affect the brain or other parts of our nervous system, and their symptoms can affect cognition, motor function and/or social interaction of the patients; we refer collectively to them as rare neurological disorders or RNDs. We have focused this review on RNDs known to have compromised protein homeostasis pathways. Proteostasis can be regulated and/or altered by a chain of cellular mechanisms, from protein synthesis and folding, to aggregation and degradation. Overall, we provide a list comprised of above 215 genes responsible for causing more than 170 distinct RNDs, deepening on some representative diseases, including as well a clinical view of how those diseases are diagnosed and dealt with. Additionally, we review existing methodologies for diagnosis and treatment, discussing the potential of specific deubiquitinating enzyme inhibition as a future therapeutic avenue for RNDs.
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Affiliation(s)
- Nerea Osinalde
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), 01006 Vitoria-Gasteiz, Spain
| | - Anna Duarri
- Barcelona Stem Cell Bank, Center of Regenerative Medicine in Barcelona, 08908 Hospitalet de Llobregat, Barcelona, Spain
| | - Juanma Ramirez
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain
| | - Rosa Barrio
- Functional Genomics Unit, CIC bioGUNE, 48160 Derio, Spain
| | - Guiomar Perez de Nanclares
- Molecular (Epi)Genetics Laboratory, BioAraba National Health Institute, Hospital Universitario Araba-Txagorritxu, Vitoria-Gasteiz, Alava, Spain
| | - Ugo Mayor
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain; Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain.
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25
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Chang CY, Ting HC, Liu CA, Su HL, Chiou TW, Harn HJ, Lin SZ. Induced Pluripotent Stem Cells: A Powerful Neurodegenerative Disease Modeling Tool for Mechanism Study and Drug Discovery. Cell Transplant 2018; 27:1588-1602. [PMID: 29890847 PMCID: PMC6299199 DOI: 10.1177/0963689718775406] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 03/30/2018] [Accepted: 04/09/2018] [Indexed: 12/12/2022] Open
Abstract
Many neurodegenerative diseases are progressive, complex diseases without clear mechanisms or effective treatments. To study the mechanisms underlying these diseases and to develop treatment strategies, a reliable in vitro modeling system is critical. Induced pluripotent stem cells (iPSCs) have the ability to self-renew and possess the differentiation potential to become any kind of adult cell; thus, they may serve as a powerful material for disease modeling. Indeed, patient cell-derived iPSCs can differentiate into specific cell lineages that display the appropriate disease phenotypes and vulnerabilities. In this review, we highlight neuronal differentiation methods and the current development of iPSC-based neurodegenerative disease modeling tools for mechanism study and drug screening, with a discussion of the challenges and future inspiration for application.
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Affiliation(s)
- Chia-Yu Chang
- Bio-innovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
- Department of Medical Research, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Hsiao-Chien Ting
- Bio-innovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - Ching-Ann Liu
- Bio-innovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
- Department of Medical Research, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
| | - Hong-Lin Su
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan
| | - Tzyy-Wen Chiou
- Department of Life Science, National Dong Hwa University, Hualien, Taiwan
| | - Horng-Jyh Harn
- Bio-innovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
- Department of Pathology, Buddhist Tzu Chi General Hospital and Tzu Chi University, Hualien, Taiwan
| | - Shinn-Zong Lin
- Bio-innovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
- Department of Neurosurgery, Buddhist Tzu Chi General Hospital, Hualien, Taiwan
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26
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Ashraf NS, Duarte-Silva S, Shaw ED, Maciel P, Paulson HL, Teixeira-Castro A, Costa MDC. Citalopram Reduces Aggregation of ATXN3 in a YAC Transgenic Mouse Model of Machado-Joseph Disease. Mol Neurobiol 2018; 56:3690-3701. [PMID: 30187384 DOI: 10.1007/s12035-018-1331-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/22/2018] [Indexed: 01/20/2023]
Abstract
Machado-Joseph disease, also known as spinocerebellar ataxia type 3, is a fatal polyglutamine disease with no disease-modifying treatment. The selective serotonin reuptake inhibitor citalopram was shown in nematode and mouse models to be a compelling repurposing candidate for Machado-Joseph disease therapeutics. We sought to confirm the efficacy of citalopram to decrease ATXN3 aggregation in an unrelated mouse model of Machado-Joseph disease. Four-week-old YACMJD84.2 mice and non-transgenic littermates were given citalopram 8 mg/kg in drinking water or water for 10 weeks. At the end of treatment, brains were collected for biochemical and pathological analyses. Brains of citalopram-treated YACMJD84.2 mice showed an approximate 50% decrease in the percentage of cells containing ATXN3-positive inclusions in the substantia nigra and three examined brainstem nuclei compared to controls. No differences in ATXN3 inclusion load were observed in deep cerebellar nuclei of mice. Citalopram effect on ATXN3 aggregate burden was corroborated by immunoblotting analysis. While lysates from the brainstem and cervical spinal cord of citalopram-treated mice showed a decrease in all soluble forms of ATXN3 and a trend toward reduction of insoluble ATXN3, no differences in ATXN3 levels were found between cerebella of citalopram-treated and vehicle-treated mice. Citalopram treatment altered levels of select components of the cellular protein homeostatic machinery that may be expected to enhance the capacity to refold and/or degrade mutant ATXN3. The results here obtained in a second independent mouse model of Machado-Joseph disease further support citalopram as a potential drug to be repurposed for this fatal disorder.
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Affiliation(s)
- Naila S Ashraf
- Department of Neurology, Michigan Medicine, University of Michigan, A. Alfred Taubman Biomedical Sciences Research Building, 109 Zina Pitcher Place, Ann Arbor, MI, 48109-2200, USA
| | - Sara Duarte-Silva
- School of Medicine, University of Minho, Campus de Gualtar, Life and Health Sciences Research Institute (ICVS), Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Emily D Shaw
- Department of Neurology, Michigan Medicine, University of Michigan, A. Alfred Taubman Biomedical Sciences Research Building, 109 Zina Pitcher Place, Ann Arbor, MI, 48109-2200, USA
| | - Patrícia Maciel
- School of Medicine, University of Minho, Campus de Gualtar, Life and Health Sciences Research Institute (ICVS), Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Henry L Paulson
- Department of Neurology, Michigan Medicine, University of Michigan, A. Alfred Taubman Biomedical Sciences Research Building, 109 Zina Pitcher Place, Ann Arbor, MI, 48109-2200, USA
| | - Andreia Teixeira-Castro
- School of Medicine, University of Minho, Campus de Gualtar, Life and Health Sciences Research Institute (ICVS), Braga, Portugal. .,ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal. .,Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208, USA.
| | - Maria do Carmo Costa
- Department of Neurology, Michigan Medicine, University of Michigan, A. Alfred Taubman Biomedical Sciences Research Building, 109 Zina Pitcher Place, Ann Arbor, MI, 48109-2200, USA.
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27
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Promoter Variant Alters Expression of the Autophagic BECN1 Gene: Implications for Clinical Manifestations of Machado-Joseph Disease. THE CEREBELLUM 2018; 16:957-963. [PMID: 28699106 DOI: 10.1007/s12311-017-0875-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Autophagy is especially important in disorders where accumulation of the mutant protein is a hallmark, such as the Machado-Joseph disease/spinocerebellar ataxia type 3 (MJD/SCA3). We analyzed the promoter of the BECN1 gene, whose overexpression has been reported to exert neuroprotective effects in MJD, with the aim of finding variants that could be associated with expression levels of beclin-1 and could be tested as modifiers of onset and disease severity. A fragment encompassing the BECN1 promoter was sequenced in 95 MJD subjects and 120 controls. The impact of the variation detected on transcription factors (TFs) binding affinity was evaluated in silico and inferences concerning levels of expression were confirmed by fluorescence-based quantitative real-time PCR in a subset of 28 MJD subjects and 26 controls. Four previously described (rs60221525, rs116943570, rs34882610, and rs34037822) and one novel (c.-933delG) variants were identified. In silico analysis performed for the most frequent variants-rs60221525 C allele and rs116943570 T allele-predicted an impact of the presence of these alleles on TF binding affinity. BECN1 expression levels were in agreement with the in silico predictions, showing a tendency for decreased levels in samples with the rs60221525 C allele and for increased levels in samples with the rs116943570 T allele. MJD patients carrying the rs60221525 C allele presented a tendency for earlier estimated age at onset. Moreover, patients with the rs60221525 C allele presented a more severe clinical picture, compared to patients without this allele. The analysis of a larger number of patients from different cohorts, currently unavailable, would be required to confirm these results.
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28
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Wu YL, Chang JC, Lin WY, Li CC, Hsieh M, Chen HW, Wang TS, Liu CS, Liu KL. Treatment with Caffeic Acid and Resveratrol Alleviates Oxidative Stress Induced Neurotoxicity in Cell and Drosophila Models of Spinocerebellar Ataxia Type3. Sci Rep 2017; 7:11641. [PMID: 28912527 PMCID: PMC5599504 DOI: 10.1038/s41598-017-11839-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 08/18/2017] [Indexed: 11/09/2022] Open
Abstract
Spinocerebellar ataxia type 3 (SCA3) is caused by the expansion of a polyglutamine (polyQ) repeat in the protein ataxin-3 which is involved in susceptibility to mild oxidative stress induced neuronal death. Here we show that caffeic acid (CA) and resveratrol (Res) decreased reactive oxygen species (ROS), mutant ataxin-3 and apoptosis and increased autophagy in the pro-oxidant tert-butyl hydroperoxide (tBH)-treated SK-N-SH-MJD78 cells containing mutant ataxin-3. Furthermore, CA and Res improved survival and locomotor activity and decreased mutant ataxin-3 and ROS levels in tBH-treated SCA3 Drosophila. CA and Res also altered p53 and nuclear factor-κB (NF-κB) activation and expression in tBH-treated cell and fly models of SCA3, respectively. Blockade of NF-κB activation annulled the protective effects of CA and Res on apoptosis, ROS, and p53 activation in tBH-treated SK-N-SH-MJD78 cells, which suggests the importance of restoring NF-κB activity by CA and Res. Our findings suggest that CA and Res may be useful in the management of oxidative stress induced neuronal apoptosis in SCA3.
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Affiliation(s)
- Yu-Ling Wu
- Department of Nutrition, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Rd., Taichung, 40203, Taiwan
| | - Jui-Chih Chang
- Vascular and Genomic Center, Changhua Christian Hospital, Changhua, 50094, Taiwan
| | - Wei-Yong Lin
- Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, No.91, Hsueh-Shih Road, Taichung, 40402, Taiwan.,Department of Medical Research, China Medical University Hospital, Taichung, 40447, Taiwan
| | - Chien-Chun Li
- Department of Nutrition, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Rd., Taichung, 40203, Taiwan.,Department of Nutrition, Chung Shan Medical University Hospital, Taichung, 40203, Taiwan
| | - Mingli Hsieh
- Department of Life Science and Life Science Research Center, Tunghai University, Taichung, 40704, Taiwan
| | - Haw-Wen Chen
- Department of Nutrition, China Medical University, Taichung, 40402, Taiwan
| | - Tsu-Shing Wang
- Department of Biomedical Sciences, Chung Shan Medical University, Taichung, 40203, Taiwan
| | - Chin-San Liu
- Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, No.91, Hsueh-Shih Road, Taichung, 40402, Taiwan. .,Department of Neurology and Vascular and Genomic Center, Changhua Christian Hospital, Changhua, 50094, Taiwan.
| | - Kai-Li Liu
- Department of Nutrition, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Rd., Taichung, 40203, Taiwan. .,Department of Nutrition, Chung Shan Medical University Hospital, Taichung, 40203, Taiwan.
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29
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Induced Pluripotent Stem Cell Neuronal Models for the Study of Autophagy Pathways in Human Neurodegenerative Disease. Cells 2017; 6:cells6030024. [PMID: 28800101 PMCID: PMC5617970 DOI: 10.3390/cells6030024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/08/2017] [Accepted: 08/09/2017] [Indexed: 02/06/2023] Open
Abstract
Human induced pluripotent stem cells (hiPSCs) are invaluable tools for research into the causes of diverse human diseases, and have enormous potential in the emerging field of regenerative medicine. Our ability to reprogramme patient cells to become hiPSCs, and to subsequently direct their differentiation towards those classes of neurons that are vulnerable to stress, is revealing how genetic mutations cause changes at the molecular level that drive the complex pathogeneses of human neurodegenerative diseases. Autophagy dysregulation is considered to be a major contributor in neural decline during the onset and progression of many human neurodegenerative diseases, meaning that a better understanding of the control of non-selective and selective autophagy pathways (including mitophagy) in disease-affected classes of neurons is needed. To achieve this, it is essential that the methodologies commonly used to study autophagy regulation under basal and stressed conditions in standard cell-line models are accurately applied when using hiPSC-derived neuronal cultures. Here, we discuss the roles and control of autophagy in human stem cells, and how autophagy contributes to neural differentiation in vitro. We also describe how autophagy-monitoring tools can be applied to hiPSC-derived neurons for the study of human neurodegenerative disease in vitro.
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30
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Hwang SP, Lee DH. Autophagy mediates SUMO-induced degradation of a polyglutamine protein ataxin-3. Anim Cells Syst (Seoul) 2017; 21:169-176. [PMID: 30460066 PMCID: PMC6138331 DOI: 10.1080/19768354.2017.1330765] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/25/2017] [Accepted: 04/30/2017] [Indexed: 01/27/2023] Open
Abstract
Previously, we reported that small ubiquitin-like modifier-1 (SUMO-1) promotes the degradation of a polyglutamine (polyQ) protein ataxin-3 and proposed that proteasomes mediate the proteolysis. Here, we present evidence that autophagy is also responsible for SUMO-induced degradation of this polyQ protein. The autophagy inhibitor 3-MA increased the steady-state level of ataxin-3 and stabilized SUMO-modified ataxin-3 more prominently than the proteasome inhibitor MG132. Interestingly, SUMO-1 overexpression enhanced the co-localization of ataxin-3 and autophagy marker LC3 without increasing LC3 puncta formation suggesting that SUMO-1 is involved in the substrate recruitment rather than the induction of autophagy. To assess the importance of a putative SUMO-interacting motif (SIM) in ataxin-3 for SUMO-induced degradation, we constructed a SIM mutant of ataxin-3. Substitution of putative SIM (V165G) facilitated the degradation of polyQ-expanded ataxin-3, which is more resistant to SUMO-induced degradation than the normal ataxin-3. These results together indicate that SUMO-1 promotes the degradation of ataxin-3 via autophagy and the putative SIM of ataxin-3 plays a role in this process.
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Affiliation(s)
- Soo Pyung Hwang
- Department of Bio and Environmental Technology, College of Natural Sciences, Seoul Women's University, Seoul, South Korea
| | - Do Hee Lee
- Department of Bio and Environmental Technology, College of Natural Sciences, Seoul Women's University, Seoul, South Korea
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