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Odierna GL, Vucic S, Dyer M, Dickson T, Woodhouse A, Blizzard C. How do we get from hyperexcitability to excitotoxicity in amyotrophic lateral sclerosis? Brain 2024; 147:1610-1621. [PMID: 38408864 PMCID: PMC11068114 DOI: 10.1093/brain/awae039] [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: 07/17/2023] [Revised: 11/15/2023] [Accepted: 12/10/2023] [Indexed: 02/28/2024] Open
Abstract
Amyotrophic lateral sclerosis is a devastating neurodegenerative disease that, at present, has no effective cure. Evidence of increased circulating glutamate and hyperexcitability of the motor cortex in patients with amyotrophic lateral sclerosis have provided an empirical support base for the 'dying forward' excitotoxicity hypothesis. The hypothesis postulates that increased activation of upper motor neurons spreads pathology to lower motor neurons in the spinal cord in the form of excessive glutamate release, which triggers excitotoxic processes. Many clinical trials have focused on therapies that target excitotoxicity via dampening neuronal activation, but not all are effective. As such, there is a growing tension between the rising tide of evidence for the 'dying forward' excitotoxicity hypothesis and the failure of therapies that target neuronal activation. One possible solution to these contradictory outcomes is that our interpretation of the current evidence requires revision in the context of appreciating the complexity of the nervous system and the limitations of the neurobiological assays we use to study it. In this review we provide an evaluation of evidence relevant to the 'dying forward' excitotoxicity hypothesis and by doing so, identify key gaps in our knowledge that need to be addressed. We hope to provide a road map from hyperexcitability to excitotoxicity so that we can better develop therapies for patients suffering from amyotrophic lateral sclerosis. We conclude that studies of upper motor neuron activity and their synaptic output will play a decisive role in the future of amyotrophic lateral sclerosis therapy.
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Affiliation(s)
- G Lorenzo Odierna
- Tasmanian School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
| | - Steve Vucic
- Brain and Nerve Research Center, The University of Sydney, Sydney 2050, Australia
| | - Marcus Dyer
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
- Department of Pharmaceutical and Pharmacological Sciences, Center for Neurosciences, Vrije Universiteit Brussel (VUB), 1090 Brussels, Belgium
| | - Tracey Dickson
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
| | - Adele Woodhouse
- The Wicking Dementia Centre, University of Tasmania, Hobart, TAS 7000, Australia
| | - Catherine Blizzard
- Tasmanian School of Medicine, University of Tasmania, Hobart, TAS 7000, Australia
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS 7000, Australia
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2
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Sellier C, Corcia P, Vourc'h P, Dupuis L. C9ORF72 hexanucleotide repeat expansion: From ALS and FTD to a broader pathogenic role? Rev Neurol (Paris) 2024; 180:417-428. [PMID: 38609750 DOI: 10.1016/j.neurol.2024.03.008] [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: 03/20/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024]
Abstract
The major gene underlying monogenic forms of amyotrophic lateral sclerosis (ALS) and fronto-temporal dementia (FTD) is C9ORF72. The causative mutation in C9ORF72 is an abnormal hexanucleotide (G4C2) repeat expansion (HRE) located in the first intron of the gene. The aim of this review is to propose a comprehensive update on recent developments on clinical, biological and therapeutics aspects related to C9ORF72 in order to highlight the current understanding of genotype-phenotype correlations, and also on biological machinery leading to neuronal death. We will particularly focus on the broad phenotypic presentation of C9ORF72-related diseases, that goes well beyond the classical phenotypes observed in ALS and FTD patients. Last, we will comment the possible therapeutical hopes for patients carrying a C9ORF72 HRE.
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Affiliation(s)
- C Sellier
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France
| | - P Corcia
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Centre constitutif de coordination SLA, CHU de Bretonneau, 2, boulevard Tonnelle, 37044 Tours cedex 1, France
| | - P Vourc'h
- UMR 1253 iBrain, Inserm, université de Tours, Tours, France; Service de biochimie et biologie moléculaire, CHU de Tours, Tours, France
| | - L Dupuis
- Centre de recherches en biomédecine de Strasbourg, UMR-S1329, Inserm, université de Strasbourg, Strasbourg, France.
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3
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Sun L, Wang Q, Ai J. The underlying roles and neurobiological mechanisms of music-based intervention in Alzheimer's disease: A comprehensive review. Ageing Res Rev 2024; 96:102265. [PMID: 38479478 DOI: 10.1016/j.arr.2024.102265] [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: 07/15/2023] [Revised: 02/25/2024] [Accepted: 03/04/2024] [Indexed: 03/19/2024]
Abstract
Non-pharmacological therapy has gained popularity in the intervention of Alzheimer's disease (AD) due to its apparent therapeutic effectiveness and the limitation of biological drug. A wealth of research indicates that music interventions can enhance cognition, mood and behavior in individuals with AD. Nonetheless, the underlying mechanisms behind these improvements have yet to be fully and systematically delineated. This review aims to holistically review how music-based intervention (MBI) ameliorates abnormal emotion, cognition decline, and behavioral changes in AD patients. We cover several key dimensions: the regulation of MBIs on cerebral blood flow (CBF), their impact on neurotransmission (including GABAergic and monoaminergic transmissions), modulation of synaptic plasticity, and hormonal release. Additionally, we summarize the clinical applications and limitations of active music-based intervention (AMBI), passive music-based intervention (PMBI), and hybrid music-based intervention (HMBI). This thorough analysis enhances our understanding of the role of MBI in AD and supports the development of non-pharmacological therapeutic strategies.
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Affiliation(s)
- Liyang Sun
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China), College of Pharmacy of Harbin Medical University, 157 Baojian Road, Harbin 150086, China
| | - Qin Wang
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China), College of Pharmacy of Harbin Medical University, 157 Baojian Road, Harbin 150086, China; Department of Breast Surgery, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin 150040, China; Heilongjiang Academy of Medical Sciences, 157 Baojian Road, Harbin 150086, China
| | - Jing Ai
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China), College of Pharmacy of Harbin Medical University, 157 Baojian Road, Harbin 150086, China; National Key Laboratory of Frigid Zone Cardiovascular Diseases, 157 Baojian Road, Harbin 150086, China.
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4
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McKeever PM, Sababi AM, Sharma R, Khuu N, Xu Z, Shen SY, Xiao S, McGoldrick P, Orouji E, Ketela T, Sato C, Moreno D, Visanji N, Kovacs GG, Keith J, Zinman L, Rogaeva E, Goodarzi H, Bader GD, Robertson J. Single-nucleus multiomic atlas of frontal cortex in amyotrophic lateral sclerosis with a deep learning-based decoding of alternative polyadenylation mechanisms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573083. [PMID: 38187588 PMCID: PMC10769403 DOI: 10.1101/2023.12.22.573083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The understanding of how different cell types contribute to amyotrophic lateral sclerosis (ALS) pathogenesis is limited. Here we generated a single-nucleus transcriptomic and epigenomic atlas of the frontal cortex of ALS cases with C9orf72 (C9) hexanucleotide repeat expansions and sporadic ALS (sALS). Our findings reveal shared pathways in C9-ALS and sALS, characterized by synaptic dysfunction in excitatory neurons and a disease-associated state in microglia. The disease subtypes diverge with loss of astrocyte homeostasis in C9-ALS, and a more substantial disturbance of inhibitory neurons in sALS. Leveraging high depth 3'-end sequencing, we found a widespread switch towards distal polyadenylation (PA) site usage across ALS subtypes relative to controls. To explore this differential alternative PA (APA), we developed APA-Net, a deep neural network model that uses transcript sequence and expression levels of RNA-binding proteins (RBPs) to predict cell-type specific APA usage and RBP interactions likely to regulate APA across disease subtypes.
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5
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Chen ZS, Ou M, Taylor S, Dafinca R, Peng SI, Talbot K, Chan HYE. Mutant GGGGCC RNA prevents YY1 from binding to Fuzzy promoter which stimulates Wnt/β-catenin pathway in C9ALS/FTD. Nat Commun 2023; 14:8420. [PMID: 38110419 PMCID: PMC10728118 DOI: 10.1038/s41467-023-44215-w] [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: 11/10/2022] [Accepted: 12/05/2023] [Indexed: 12/20/2023] Open
Abstract
The GGGGCC hexanucleotide repeat expansion mutation in the chromosome 9 open reading frame 72 (C9orf72) gene is a major genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9ALS/FTD). In this study, we demonstrate that the zinc finger (ZF) transcriptional regulator Yin Yang 1 (YY1) binds to the promoter region of the planar cell polarity gene Fuzzy to regulate its transcription. We show that YY1 interacts with GGGGCC repeat RNA via its ZF and that this interaction compromises the binding of YY1 to the FuzzyYY1 promoter sites, resulting in the downregulation of Fuzzy transcription. The decrease in Fuzzy protein expression in turn activates the canonical Wnt/β-catenin pathway and induces synaptic deficits in C9ALS/FTD neurons. Our findings demonstrate a C9orf72 GGGGCC RNA-initiated perturbation of YY1-Fuzzy transcriptional control that implicates aberrant Wnt/β-catenin signalling in C9ALS/FTD-associated neurodegeneration. This pathogenic cascade provides a potential new target for disease-modifying therapy.
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Affiliation(s)
- Zhefan Stephen Chen
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
- Oxford Motor Neuron Disease Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Mingxi Ou
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Stephanie Taylor
- Oxford Motor Neuron Disease Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
| | - Ruxandra Dafinca
- Oxford Motor Neuron Disease Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK
| | - Shaohong Isaac Peng
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Kevin Talbot
- Oxford Motor Neuron Disease Centre, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, UK.
- Kavli Institute for Nanoscience Discovery, University of Oxford, Dorothy Crowfoot Hodgkin Building, South Parks Road, Oxford, OX1 3QU, UK.
| | - Ho Yin Edwin Chan
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
- Gerald Choa Neuroscience Institute, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China.
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6
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Sattler R, Traynor BJ, Robertson J, Van Den Bosch L, Barmada SJ, Svendsen CN, Disney MD, Gendron TF, Wong PC, Turner MR, Boxer A, Babu S, Benatar M, Kurnellas M, Rohrer JD, Donnelly CJ, Bustos LM, Van Keuren-Jensen K, Dacks PA, Sabbagh MN. Roadmap for C9ORF72 in Frontotemporal Dementia and Amyotrophic Lateral Sclerosis: Report on the C9ORF72 FTD/ALS Summit. Neurol Ther 2023; 12:1821-1843. [PMID: 37847372 PMCID: PMC10630271 DOI: 10.1007/s40120-023-00548-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 09/14/2023] [Indexed: 10/18/2023] Open
Abstract
A summit held March 2023 in Scottsdale, Arizona (USA) focused on the intronic hexanucleotide expansion in the C9ORF72 gene and its relevance in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS; C9ORF72-FTD/ALS). The goal of this summit was to connect basic scientists, clinical researchers, drug developers, and individuals affected by C9ORF72-FTD/ALS to evaluate how collaborative efforts across the FTD-ALS disease spectrum might break down existing disease silos. Presentations and discussions covered recent discoveries in C9ORF72-FTD/ALS disease mechanisms, availability of disease biomarkers and recent advances in therapeutic development, and clinical trial design for prevention and treatment for individuals affected by C9ORF72-FTD/ALS and asymptomatic pathological expansion carriers. The C9ORF72-associated hexanucleotide repeat expansion is an important locus for both ALS and FTD. C9ORF72-FTD/ALS may be characterized by loss of function of the C9ORF72 protein and toxic gain of functions caused by both dipeptide repeat (DPR) proteins and hexanucleotide repeat RNA. C9ORF72-FTD/ALS therapeutic strategies discussed at the summit included the use of antisense oligonucleotides, adeno-associated virus (AAV)-mediated gene silencing and gene delivery, and engineered small molecules targeting RNA structures associated with the C9ORF72 expansion. Neurofilament light chain, DPR proteins, and transactive response (TAR) DNA-binding protein 43 (TDP-43)-associated molecular changes were presented as biomarker candidates. Similarly, brain imaging modalities (i.e., magnetic resonance imaging [MRI] and positron emission tomography [PET]) measuring structural, functional, and metabolic changes were discussed as important tools to monitor individuals affected with C9ORF72-FTD/ALS, at both pre-symptomatic and symptomatic disease stages. Finally, summit attendees evaluated current clinical trial designs available for FTD or ALS patients and concluded that therapeutics relevant to FTD/ALS patients, such as those specifically targeting C9ORF72, may need to be tested with composite endpoints covering clinical symptoms of both FTD and ALS. The latter will require novel clinical trial designs to be inclusive of all patient subgroups spanning the FTD/ALS spectrum.
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Affiliation(s)
- Rita Sattler
- Barrow Neurological Institute, 2910 N Third Ave, Phoenix, AZ, 85013, USA.
| | - Bryan J Traynor
- Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada
| | - Ludo Van Den Bosch
- VIB, Center for Brain & Disease Research, Laboratory of Neurobiology and KU Leuven, Leuven, Belgium
- Department of Neurosciences, Experimental Neurology and Leuven Brain Institute (LBI), University of Leuven, Leuven, Belgium
| | - Sami J Barmada
- Department of Neurology, Neuroscience Program, University of Michigan, Ann Arbor, MI, USA
| | - Clive N Svendsen
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Matthew D Disney
- Department of Chemistry, The Herbert Wertheim UF-Scripps Institute for Biomedical Research and Innovation, The Scripps Research Institute, Jupiter, FL, USA
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Philip C Wong
- Departments of Pathology and Neuroscience, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Martin R Turner
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Adam Boxer
- Department of Neurology, Memory and Aging Center, Weill Institute for Neurosciences, University of San Francisco, San Francisco, CA, USA
| | - Suma Babu
- Sean M. Healey and AMG Center for ALS and the Neurological Clinical Research Institute, Massachusetts General Hospital-Harvard Medical School, Boston, MA, USA
| | - Michael Benatar
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, 33129, USA
| | | | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Christopher J Donnelly
- LiveLikeLou Center for ALS Research, Brain Institute, University of Pittsburgh, Pittsburgh, USA
- Department of Neurobiology, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lynette M Bustos
- Barrow Neurological Institute, 2910 N Third Ave, Phoenix, AZ, 85013, USA
| | | | - Penny A Dacks
- The Association for Frontotemporal Degeneration and FTD Disorders Registry, King of Prussia, PA, USA
| | - Marwan N Sabbagh
- Barrow Neurological Institute, 2910 N Third Ave, Phoenix, AZ, 85013, USA.
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7
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Catanese A, Rajkumar S, Sommer D, Masrori P, Hersmus N, Van Damme P, Witzel S, Ludolph A, Ho R, Boeckers TM, Mulaw M. Multiomics and machine-learning identify novel transcriptional and mutational signatures in amyotrophic lateral sclerosis. Brain 2023; 146:3770-3782. [PMID: 36883643 PMCID: PMC10473564 DOI: 10.1093/brain/awad075] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/15/2023] [Accepted: 02/25/2023] [Indexed: 03/09/2023] Open
Abstract
Amyotrophic lateral sclerosis is a fatal and incurable neurodegenerative disease that mainly affects the neurons of the motor system. Despite the increasing understanding of its genetic components, their biological meanings are still poorly understood. Indeed, it is still not clear to which extent the pathological features associated with amyotrophic lateral sclerosis are commonly shared by the different genes causally linked to this disorder. To address this point, we combined multiomics analysis covering the transcriptional, epigenetic and mutational aspects of heterogenous human induced pluripotent stem cell-derived C9orf72-, TARDBP-, SOD1- and FUS-mutant motor neurons as well as datasets from patients' biopsies. We identified a common signature, converging towards increased stress and synaptic abnormalities, which reflects a unifying transcriptional program in amyotrophic lateral sclerosis despite the specific profiles due to the underlying pathogenic gene. In addition, whole genome bisulphite sequencing linked the altered gene expression observed in mutant cells to their methylation profile, highlighting deep epigenetic alterations as part of the abnormal transcriptional signatures linked to amyotrophic lateral sclerosis. We then applied multi-layer deep machine-learning to integrate publicly available blood and spinal cord transcriptomes and found a statistically significant correlation between their top predictor gene sets, which were significantly enriched in toll-like receptor signalling. Notably, the overrepresentation of this biological term also correlated with the transcriptional signature identified in mutant human induced pluripotent stem cell-derived motor neurons, highlighting novel insights into amyotrophic lateral sclerosis marker genes in a tissue-independent manner. Finally, using whole genome sequencing in combination with deep learning, we generated the first mutational signature for amyotrophic lateral sclerosis and defined a specific genomic profile for this disease, which is significantly correlated to ageing signatures, hinting at age as a major player in amyotrophic lateral sclerosis. This work describes innovative methodological approaches for the identification of disease signatures through the combination of multiomics analysis and provides novel knowledge on the pathological convergencies defining amyotrophic lateral sclerosis.
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Affiliation(s)
- Alberto Catanese
- Institute of Anatomy and Cell Biology, Ulm University School of Medicine, 89081 Ulm, Germany
- Translational Protein Biochemistry, German Center for Neurodegenerative Diseases (DZNE), Ulm site, 89081 Ulm, Germany
| | - Sandeep Rajkumar
- Institute of Anatomy and Cell Biology, Ulm University School of Medicine, 89081 Ulm, Germany
| | - Daniel Sommer
- Institute of Anatomy and Cell Biology, Ulm University School of Medicine, 89081 Ulm, Germany
| | - Pegah Masrori
- Laboratory of Neurobiology, Center for Brain & Disease Research, VIB, 3000 Leuven, Belgium
- Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
- Experimental Neurology, Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Nicole Hersmus
- Laboratory of Neurobiology, Center for Brain & Disease Research, VIB, 3000 Leuven, Belgium
- Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
- Experimental Neurology, Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Philip Van Damme
- Laboratory of Neurobiology, Center for Brain & Disease Research, VIB, 3000 Leuven, Belgium
- Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium
- Experimental Neurology, Department of Neurosciences, Leuven Brain Institute, KU Leuven, 3000 Leuven, Belgium
| | - Simon Witzel
- Department of Neurology, Ulm University School of Medicine, 89081 Ulm, Germany
| | - Albert Ludolph
- Translational Protein Biochemistry, German Center for Neurodegenerative Diseases (DZNE), Ulm site, 89081 Ulm, Germany
- Department of Neurology, Ulm University School of Medicine, 89081 Ulm, Germany
| | - Ritchie Ho
- Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
- Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Tobias M Boeckers
- Institute of Anatomy and Cell Biology, Ulm University School of Medicine, 89081 Ulm, Germany
- Translational Protein Biochemistry, German Center for Neurodegenerative Diseases (DZNE), Ulm site, 89081 Ulm, Germany
| | - Medhanie Mulaw
- Unit for Single-Cell Genomics, Medical Faculty, Ulm University, 89081 Ulm, Germany
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8
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Aly A, Laszlo ZI, Rajkumar S, Demir T, Hindley N, Lamont DJ, Lehmann J, Seidel M, Sommer D, Franz-Wachtel M, Barletta F, Heumos S, Czemmel S, Kabashi E, Ludolph A, Boeckers TM, Henstridge CM, Catanese A. Integrative proteomics highlight presynaptic alterations and c-Jun misactivation as convergent pathomechanisms in ALS. Acta Neuropathol 2023; 146:451-475. [PMID: 37488208 PMCID: PMC10412488 DOI: 10.1007/s00401-023-02611-y] [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: 02/17/2023] [Revised: 07/05/2023] [Accepted: 07/06/2023] [Indexed: 07/26/2023]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease mainly affecting upper and lower motoneurons. Several functionally heterogeneous genes have been associated with the familial form of this disorder (fALS), depicting an extremely complex pathogenic landscape. This heterogeneity has limited the identification of an effective therapy, and this bleak prognosis will only improve with a greater understanding of convergent disease mechanisms. Recent evidence from human post-mortem material and diverse model systems has highlighted the synapse as a crucial structure actively involved in disease progression, suggesting that synaptic aberrations might represent a shared pathological feature across the ALS spectrum. To test this hypothesis, we performed the first comprehensive analysis of the synaptic proteome from post-mortem spinal cord and human iPSC-derived motoneurons carrying mutations in the major ALS genes. This integrated approach highlighted perturbations in the molecular machinery controlling vesicle release as a shared pathomechanism in ALS. Mechanistically, phosphoproteomic analysis linked the presynaptic vesicular phenotype to an accumulation of cytotoxic protein aggregates and to the pro-apoptotic activation of the transcription factor c-Jun, providing detailed insights into the shared pathobiochemistry in ALS. Notably, sub-chronic treatment of our iPSC-derived motoneurons with the fatty acid docosahexaenoic acid exerted a neuroprotective effect by efficiently rescuing the alterations revealed by our multidisciplinary approach. Together, this study provides strong evidence for the central and convergent role played by the synaptic microenvironment within the ALS spinal cord and highlights a potential therapeutic target that counteracts degeneration in a heterogeneous cohort of human motoneuron cultures.
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Affiliation(s)
- Amr Aly
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Zsofia I Laszlo
- Division of Cellular and Systems Medicine, School of Medicine, University of Dundee, Dundee, Scotland, UK
| | - Sandeep Rajkumar
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Tugba Demir
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Nicole Hindley
- Division of Cellular and Systems Medicine, School of Medicine, University of Dundee, Dundee, Scotland, UK
| | - Douglas J Lamont
- FingerPrints Proteomics Facility, Discovery Centre, School of Life Sciences, University of Dundee, Dundee, Scotland, UK
| | - Johannes Lehmann
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Mira Seidel
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | - Daniel Sommer
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
| | | | - Francesca Barletta
- Quantitative Biology Center (QBiC), University of Tübingen, 72076, Tübingen, Germany
| | - Simon Heumos
- Quantitative Biology Center (QBiC), University of Tübingen, 72076, Tübingen, Germany
- Biomedical Data Science, Department of Computer Science, University of Tübingen, 72076, Tübingen, Germany
| | - Stefan Czemmel
- Quantitative Biology Center (QBiC), University of Tübingen, 72076, Tübingen, Germany
| | - Edor Kabashi
- Laboratory of Translational Research for Neurological Disorders, Imagine Institute, Université de Paris, INSERM, UMR 1163, 75015, Paris, France
| | - Albert Ludolph
- Department of Neurology, Ulm University School of Medicine, Ulm, Germany
- German Center for Neurodegenerative Diseases (DZNE), Ulm Site, Germany
| | - Tobias M Boeckers
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
- German Center for Neurodegenerative Diseases (DZNE), Ulm Site, Germany
| | - Christopher M Henstridge
- Division of Cellular and Systems Medicine, School of Medicine, University of Dundee, Dundee, Scotland, UK.
| | - Alberto Catanese
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany.
- German Center for Neurodegenerative Diseases (DZNE), Ulm Site, Germany.
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9
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Broadhead MJ, Ayvazian-Hancock A, Doucet K, Kantelberg O, Motherwell L, Zhu F, Grant SGN, Horrocks MH, Miles GB. Synaptic expression of TAR-DNA-binding protein 43 in the mouse spinal cord determined using super-resolution microscopy. Front Mol Neurosci 2023; 16:1027898. [PMID: 37671010 PMCID: PMC10475998 DOI: 10.3389/fnmol.2023.1027898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 06/22/2023] [Indexed: 09/07/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is characterised by a loss of motor neurons in the brain and spinal cord that is preceded by early-stage changes in synapses that may be associated with TAR-DNA-Binding Protein 43 (TDP-43) pathology. Cellular inclusions of hyperphosphorylated TDP-43 (pTDP-43) are a key hallmark of neurodegenerative diseases such ALS. However, there has been little characterisation of the synaptic expression of TDP-43 inside subpopulations of spinal cord synapses. This study utilises a range of high-resolution and super-resolution microscopy techniques with immunolabelling, as well as an aptamer-based TDP-43 labelling strategy visualised with single-molecule localisation microscopy, to characterise and quantify the presence of pTDP-43 in populations of excitatory synapses near where motor neurons reside in the lateral ventral horn of the mouse lumbar spinal cord. We observe that TDP-43 is expressed in approximately half of spinal cord synapses as nanoscale clusters. Synaptic TDP-43 clusters are found most abundantly at synapses associated with VGLUT1-positive presynaptic terminals, compared to VGLUT2-associated synapses. Our nanoscopy techniques showed no difference in the subsynaptic expression of pTDP-43 in the ALS mouse model, SOD1G93a, compared to healthy controls, despite prominent structural deficits in VGLUT1-associated synapses in SOD1G93a mice. This research characterises the basic synaptic expression of TDP-43 with nanoscale precision and provides a framework with which to investigate the potential relationship between TDP-43 pathology and synaptic pathology in neurodegenerative diseases.
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Affiliation(s)
- Matthew J. Broadhead
- School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, United Kingdom
- Centre of Biophotonics, University of St. Andrews, St. Andrews, United Kingdom
- Edinburgh Super-Resolution Imaging Consortium, Heriot-Watt University, Edinburgh, United Kingdom
| | - Ani Ayvazian-Hancock
- School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, United Kingdom
- Centre of Biophotonics, University of St. Andrews, St. Andrews, United Kingdom
| | - Katherine Doucet
- School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, United Kingdom
- Centre of Biophotonics, University of St. Andrews, St. Andrews, United Kingdom
| | - Owen Kantelberg
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
| | - Lesley Motherwell
- School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, United Kingdom
- Centre of Biophotonics, University of St. Andrews, St. Andrews, United Kingdom
| | - Fei Zhu
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Seth G. N. Grant
- Genes to Cognition Program, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain (SIDB), Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Mathew H. Horrocks
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
- IRR Chemistry Hub, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh, United Kingdom
| | - Gareth B. Miles
- School of Psychology and Neuroscience, University of St. Andrews, St. Andrews, United Kingdom
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10
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Ghaffari LT, Trotti D, Haeusler AR. Differential response of C9orf72 transcripts following neuronal depolarization. iScience 2023; 26:106959. [PMID: 37332610 PMCID: PMC10272498 DOI: 10.1016/j.isci.2023.106959] [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: 01/24/2023] [Revised: 04/19/2023] [Accepted: 05/22/2023] [Indexed: 06/20/2023] Open
Abstract
The (G4C2)n nucleotide repeat expansion (NRE) mutation in C9orf72 is the most common genetic cause of ALS and FTD. The biological functions of C9orf72 are becoming understood, but it is unclear if this gene is regulated in a neural-specific manner. Neuronal activity is a crucial modifier of biological processes in health and neurodegenerative disease contexts. Here, we show that prolonged membrane depolarization in healthy human iPSC-cortical neurons leads to a significant downregulation of a transcript variant 3 (V3) of C9orf72, with a concomitant increase in variant 2 (V2), which leads to total C9orf72 RNA transcript levels remaining unchanged. However, the same response is not observed in cortical neurons derived from patients with the C9-NRE mutation. These findings reveal the impact of depolarization on C9orf72 transcripts, and how this response diverges in C9-NRE-carriers, which may have important implications in the underlying unique clinical associations of C9-NRE transcripts and disease pathogenesis.
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Affiliation(s)
- Layla T. Ghaffari
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Davide Trotti
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Aaron R. Haeusler
- Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
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11
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Zhang Y, Huang J, Yu K, Cui X. G-Quadruplexes Formation by the C9orf72 Nucleotide Repeat Expansion d(GGGGCC) n and Conformation Regulation by Fangchinoline. Molecules 2023; 28:4671. [PMID: 37375224 DOI: 10.3390/molecules28124671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
The G-quadruplex (GQ)-forming hexanucleotide repeat expansion (HRE) in the C9orf72 (C9) gene has been found to be the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (collectively, C9ALS/FTD), implying the great significance of modulating C9-HRE GQ structures in C9ALS/FTD therapeutic treatment strategies. In this study, we investigated the GQ structures formed by varied lengths of C9-HRE DNA sequences d(GGGGCC)4 (C9-24mer) and d(GGGGCC)8 (C9-48mer), and found that the C9-24mer forms anti-parallel GQ (AP-GQ) in the presence of potassium ions, while the long C9-48mer bearing eight guanine tracts forms unstacked tandem GQ consisting of two C9-24mer unimolecular AP-GQs. Moreover, the natural small molecule Fangchinoline was screened out in order to be able to stabilize and alter the C9-HRE DNA to parallel GQ topology. Further study of the interaction of Fangchinoline with the C9-HRE RNA GQ unit r(GGGGCC)4 (C9-RNA) revealed that it can also recognize and improve the thermal stability of C9-HRE RNA GQ. Finally, use of AutoDock simulation results indicated that Fangchinoline binds to the groove regions of the parallel C9-HRE GQs. These findings pave the way for further studies of GQ structures formed by pathologically related long C9-HRE sequences, and also provide a natural small-molecule ligand that modulates the structure and stability of C9-HRE GQ, both in DNA and RNA levels. Altogether, this work may contribute to therapeutic approaches of C9ALS/FTD which take the upstream C9-HRE DNA region, as well as the toxic C9-HRE RNA, as targets.
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Affiliation(s)
- Yun Zhang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Junliu Huang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Kainan Yu
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Xiaojie Cui
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
- Key Laboratory of Ecology and Environment in Minority Areas (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China
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12
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Gulino R. Synaptic Dysfunction and Plasticity in Amyotrophic Lateral Sclerosis. Int J Mol Sci 2023; 24:ijms24054613. [PMID: 36902042 PMCID: PMC10003601 DOI: 10.3390/ijms24054613] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/03/2023] Open
Abstract
Recent evidence has supported the hypothesis that amyotrophic lateral sclerosis (ALS) is a multi-step disease, as the onset of symptoms occurs after sequential exposure to a defined number of risk factors. Despite the lack of precise identification of these disease determinants, it is known that genetic mutations may contribute to one or more of the steps leading to ALS onset, the remaining being linked to environmental factors and lifestyle. It also appears evident that compensatory plastic changes taking place at all levels of the nervous system during ALS etiopathogenesis may likely counteract the functional effects of neurodegeneration and affect the timing of disease onset and progression. Functional and structural events of synaptic plasticity probably represent the main mechanisms underlying this adaptive capability, causing a significant, although partial and transient, resiliency of the nervous system affected by a neurodegenerative disease. On the other hand, the failure of synaptic functions and plasticity may be part of the pathological process. The aim of this review was to summarize what it is known today about the controversial involvement of synapses in ALS etiopathogenesis, and an analysis of the literature, although not exhaustive, confirmed that synaptic dysfunction is an early pathogenetic process in ALS. Moreover, it appears that adequate modulation of structural and functional synaptic plasticity may likely support function sparing and delay disease progression.
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Affiliation(s)
- Rosario Gulino
- Department of Biomedical and Biotechnological Sciences, Physiology Section, University of Catania, 95123 Catania, Italy
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13
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Bauer CS, Webster CP, Shaw AC, Kok JR, Castelli LM, Lin YH, Smith EF, Illanes-Álvarez F, Higginbottom A, Shaw PJ, Azzouz M, Ferraiuolo L, Hautbergue GM, Grierson AJ, De Vos KJ. Loss of TMEM106B exacerbates C9ALS/FTD DPR pathology by disrupting autophagosome maturation. Front Cell Neurosci 2022; 16:1061559. [PMID: 36619668 PMCID: PMC9812496 DOI: 10.3389/fncel.2022.1061559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/22/2022] [Indexed: 12/23/2022] Open
Abstract
Disruption to protein homeostasis caused by lysosomal dysfunction and associated impairment of autophagy is a prominent pathology in amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD). The most common genetic cause of ALS/FTD is a G4C2 hexanucleotide repeat expansion in C9orf72 (C9ALS/FTD). Repeat-associated non-AUG (RAN) translation of G4C2 repeat transcripts gives rise to dipeptide repeat (DPR) proteins that have been shown to be toxic and may contribute to disease etiology. Genetic variants in TMEM106B have been associated with frontotemporal lobar degeneration with TDP-43 pathology and disease progression in C9ALS/FTD. TMEM106B encodes a lysosomal transmembrane protein of unknown function that is involved in various aspects of lysosomal biology. How TMEM106B variants affect C9ALS/FTD is not well understood but has been linked to changes in TMEM106B protein levels. Here, we investigated TMEM106B function in the context of C9ALS/FTD DPR pathology. We report that knockdown of TMEM106B expression exacerbates the accumulation of C9ALS/FTD-associated cytotoxic DPR proteins in cell models expressing RAN-translated or AUG-driven DPRs as well as in C9ALS/FTD-derived iAstrocytes with an endogenous G4C2 expansion by impairing autophagy. Loss of TMEM106B caused a block late in autophagy by disrupting autophagosome to autolysosome maturation which coincided with impaired lysosomal acidification, reduced cathepsin activity, and juxtanuclear clustering of lysosomes. Lysosomal clustering required Rab7A and coincided with reduced Arl8b-mediated anterograde transport of lysosomes to the cell periphery. Increasing Arl8b activity in TMEM106B-deficient cells not only restored the distribution of lysosomes, but also fully rescued autophagy and DPR protein accumulation. Thus, we identified a novel function of TMEM106B in autophagosome maturation via Arl8b. Our findings indicate that TMEM106B variants may modify C9ALS/FTD by regulating autophagic clearance of DPR proteins. Caution should therefore be taken when considering modifying TMEM106B expression levels as a therapeutic approach in ALS/FTD.
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Affiliation(s)
- Claudia S. Bauer
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Christopher P. Webster
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Allan C. Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Jannigje R. Kok
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Lydia M. Castelli
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Ya-Hui Lin
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Emma F. Smith
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Francisco Illanes-Álvarez
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Adrian Higginbottom
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Pamela J. Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Mimoun Azzouz
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Laura Ferraiuolo
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Guillaume M. Hautbergue
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Andrew J. Grierson
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
| | - Kurt J. De Vos
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
- Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom
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14
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Ghaffari LT, Trotti D, Haeusler AR, Jensen BK. Breakdown of the central synapses in C9orf72-linked ALS/FTD. Front Mol Neurosci 2022; 15:1005112. [PMID: 36187344 PMCID: PMC9523884 DOI: 10.3389/fnmol.2022.1005112] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 08/29/2022] [Indexed: 01/07/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, fatal neurodegenerative disease that leads to the death of motor and cortical neurons. The clinical manifestations of ALS are heterogenous, and efficacious treatments to significantly slow the progression of the disease are lacking. Cortical hyper-excitability is observed pre-symptomatically across disease-causative genetic variants, as well as in the early stages of sporadic ALS, and typically precedes motor neuron involvement and overt neurodegeneration. The causes of cortical hyper-excitability are not yet fully understood but is mainly agreed to be an early event. The identification of the nucleotide repeat expansion (GGGGCC)n in the C9ORF72 gene has provided evidence that ALS and another neurodegenerative disease, frontotemporal dementia (FTD), are part of a disease spectrum with common genetic origins. ALS and FTD are diseases in which synaptic dysfunction is reported throughout disease onset and stages of progression. It has become apparent that ALS/FTD-causative genes, such as C9ORF72, may have roles in maintaining the normal physiology of the synapse, as mutations in these genes often manifest in synaptic dysfunction. Here we review the dysfunctions of the central nervous system synapses associated with the nucleotide repeat expansion in C9ORF72 observed in patients, organismal, and cellular models of ALS and FTD.
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