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Vassileff N, Spiers JG, Lee JD, Woodruff TM, Ebrahimie E, Mohammadi Dehcheshmeh M, Hill AF, Cheng L. A Panel of miRNA Biomarkers Common to Serum and Brain-Derived Extracellular Vesicles Identified in Mouse Model of Amyotrophic Lateral Sclerosis. Mol Neurobiol 2024; 61:5901-5915. [PMID: 38252383 PMCID: PMC11249427 DOI: 10.1007/s12035-023-03857-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 12/05/2023] [Indexed: 01/23/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease characterised by the deposition of aggregated proteins including TAR DNA-binding protein 43 (TDP-43) in vulnerable motor neurons and the brain. Extracellular vesicles (EVs) facilitate the spread of neurodegenerative diseases and can be easily accessed in the bloodstream. This study aimed to identify a panel of EV miRNAs that can capture the pathology occurring in the brain and peripheral circulation. EVs were isolated from the cortex (BDEVs) and serum (serum EVs) of 3 month-old and 6-month-old TDP-43*Q331K and TDP-43*WT mice. Following characterisation and miRNA isolation, the EVs underwent next-generation sequencing where 24 differentially packaged miRNAs were identified in the TDP-43*Q331K BDEVs and 7 in the TDP-43*Q331K serum EVs. Several miRNAs, including miR-183-5p, were linked to ALS. Additionally, miR-122-5p and miR-486b-5p were identified in both panels, demonstrating the ability of the serum EVs to capture the dysregulation occurring in the brain. This is the first study to identify miRNAs common to both the serum EVs and BDEVs in a mouse model of ALS.
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Affiliation(s)
- Natasha Vassileff
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
| | - Jereme G Spiers
- Clear Vision Research, Eccles Institute of Neuroscience, John Curtin School of Medical Research, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
- School of Medicine and Psychology, College of Health and Medicine, The Australian National University, Acton, ACT, Australia
| | - John D Lee
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Australia
| | - Trent M Woodruff
- School of Biomedical Sciences, The University of Queensland, St. Lucia, Australia
| | - Esmaeil Ebrahimie
- Genomics Research Platform, School of Agriculture, Biomedicine and Environment, La Trobe University, Melbourne, VIC, 3000, Australia
- School of Animal and Veterinary Sciences, The University of Adelaide, Adelaide, SA, 5371, Australia
- School of BioSciences, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | | | - Andrew F Hill
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia
- Institute for Health and Sport, Victoria University, Footscray, Victoria, Australia
| | - Lesley Cheng
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, Australia.
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2
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Cheung SW, Willis EF, Simmons DG, Bellingham MC, Noakes PG. Phagocytosis of aggrecan-positive perineuronal nets surrounding motor neurons by reactive microglia expressing MMP-9 in TDP-43 Q331K ALS model mice. Neurobiol Dis 2024; 200:106614. [PMID: 39067491 DOI: 10.1016/j.nbd.2024.106614] [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: 01/16/2024] [Revised: 07/22/2024] [Accepted: 07/23/2024] [Indexed: 07/30/2024] Open
Abstract
Perineuronal nets (PNNs) are extracellular matrix structures that surround excitable neurons and their proximal dendrites. PNNs play an important role in neuroprotection against oxidative stress. Oxidative stress within motor neurons can act as a trigger for neuronal death, and this has been implicated in motor neuron degeneration in amyotrophic lateral sclerosis (ALS). We therefore characterised PNNs around alpha motor neurons and the possible contributing cellular factors in the mutant TDP-43Q331K transgenic mouse, a slow onset ALS mouse model. PNNs around alpha motor neurons showed significant loss at mid-stage disease in TDP-43Q331K mice compared to wild type strain control mice. PNN loss coincided with an increased expression of matrix metallopeptidase-9 (MMP-9), an endopeptidase known to cleave PNNs, within the ventral horn. During mid-stage disease, increased numbers of microglia and astrocytes expressing MMP-9 were present in the ventral horn of TDP-43Q331K mice. In addition, TDP-43Q331K mice showed increased levels of aggrecan, a PNN component, in the ventral horn by microglia and astrocytes during this period. Elevated aggrecan levels within glia were accompanied by an increase in fractalkine expression, a chemotaxic protein responsible for the recruitment of microglia, in alpha motor neurons of onset and mid-stage TDP-43Q331K mice. Following PNN loss, alpha motor neurons in mid-stage TDP-43Q331K mice showed increased 3-nitrotyrosine expression, an indicator of protein oxidation. Together, our observations along with previous PNN research provide suggests a possible model whereby microglia and astrocytes expressing MMP-9 degrade PNNs surrounding alpha motor neurons in the TDP-43Q331K mouse. This loss of nets may expose alpha-motor neurons to oxidative damage leading to degeneration of the alpha motor neurons in the TDP-43Q331K ALS mouse model.
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Affiliation(s)
- Sang Won Cheung
- School of Biomedical Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Emily F Willis
- School of Biomedical Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - David G Simmons
- School of Biomedical Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Mark C Bellingham
- School of Biomedical Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Peter G Noakes
- School of Biomedical Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia; Queensland Brain Institute, The University of Queensland, St. Lucia, QLD 4072, Australia.
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3
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Clayton EL, Huggon L, Cousin MA, Mizielinska S. Synaptopathy: presynaptic convergence in frontotemporal dementia and amyotrophic lateral sclerosis. Brain 2024; 147:2289-2307. [PMID: 38451707 PMCID: PMC11224618 DOI: 10.1093/brain/awae074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 02/02/2024] [Accepted: 02/12/2024] [Indexed: 03/09/2024] Open
Abstract
Frontotemporal dementia and amyotrophic lateral sclerosis are common forms of neurodegenerative disease that share overlapping genetics and pathologies. Crucially, no significantly disease-modifying treatments are available for either disease. Identifying the earliest changes that initiate neuronal dysfunction is important for designing effective intervention therapeutics. The genes mutated in genetic forms of frontotemporal dementia and amyotrophic lateral sclerosis have diverse cellular functions, and multiple disease mechanisms have been proposed for both. Identification of a convergent disease mechanism in frontotemporal dementia and amyotrophic lateral sclerosis would focus research for a targetable pathway, which could potentially effectively treat all forms of frontotemporal dementia and amyotrophic lateral sclerosis (both familial and sporadic). Synaptopathies are diseases resulting from physiological dysfunction of synapses, and define the earliest stages in multiple neuronal diseases, with synapse loss a key feature in dementia. At the presynapse, the process of synaptic vesicle recruitment, fusion and recycling is necessary for activity-dependent neurotransmitter release. The unique distal location of the presynaptic terminal means the tight spatio-temporal control of presynaptic homeostasis is dependent on efficient local protein translation and degradation. Recently, numerous publications have shown that mutations associated with frontotemporal dementia and amyotrophic lateral sclerosis present with synaptopathy characterized by presynaptic dysfunction. This review will describe the complex local signalling and membrane trafficking events that occur at the presynapse to facilitate neurotransmission and will summarize recent publications linking frontotemporal dementia/amyotrophic lateral sclerosis genetic mutations to presynaptic function. This evidence indicates that presynaptic synaptopathy is an early and convergent event in frontotemporal dementia and amyotrophic lateral sclerosis and illustrates the need for further research in this area, to identify potential therapeutic targets with the ability to impact this convergent pathomechanism.
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Affiliation(s)
- Emma L Clayton
- UK Dementia Research Institute at King’s College London, London SE5 9RT, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, Maurice Wohl Clinical Neuroscience Institute, London SE5 9RT, UK
| | - Laura Huggon
- UK Dementia Research Institute at King’s College London, London SE5 9RT, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, Maurice Wohl Clinical Neuroscience Institute, London SE5 9RT, UK
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh EH8 9XD, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Sarah Mizielinska
- UK Dementia Research Institute at King’s College London, London SE5 9RT, UK
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, Maurice Wohl Clinical Neuroscience Institute, London SE5 9RT, UK
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Pandya VA, Patani R. The role of glial cells in amyotrophic lateral sclerosis. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2024; 176:381-450. [PMID: 38802179 DOI: 10.1016/bs.irn.2024.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) has traditionally been considered a neuron-centric disease. This view is now outdated, with increasing recognition of cell autonomous and non-cell autonomous contributions of central and peripheral nervous system glia to ALS pathomechanisms. With glial research rapidly accelerating, we comprehensively interrogate the roles of astrocytes, microglia, oligodendrocytes, ependymal cells, Schwann cells and satellite glia in nervous system physiology and ALS-associated pathology. Moreover, we highlight the inter-glial, glial-neuronal and inter-system polylogue which constitutes the healthy nervous system and destabilises in disease. We also propose classification based on function for complex glial reactive phenotypes and discuss the pre-requisite for integrative modelling to advance translation. Given the paucity of life-enhancing therapies currently available for ALS patients, we discuss the promising potential of harnessing glia in driving ALS therapeutic discovery.
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Affiliation(s)
- Virenkumar A Pandya
- University College London Medical School, London, United Kingdom; The Francis Crick Institute, London, United Kingdom.
| | - Rickie Patani
- The Francis Crick Institute, London, United Kingdom; Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology, Queen Square, London, United Kingdom.
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Salzinger A, Ramesh V, Das Sharma S, Chandran S, Thangaraj Selvaraj B. Neuronal Circuit Dysfunction in Amyotrophic Lateral Sclerosis. Cells 2024; 13:792. [PMID: 38786016 PMCID: PMC11120636 DOI: 10.3390/cells13100792] [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: 03/19/2024] [Revised: 04/27/2024] [Accepted: 04/30/2024] [Indexed: 05/25/2024] Open
Abstract
The primary neural circuit affected in Amyotrophic Lateral Sclerosis (ALS) patients is the corticospinal motor circuit, originating in upper motor neurons (UMNs) in the cerebral motor cortex which descend to synapse with the lower motor neurons (LMNs) in the spinal cord to ultimately innervate the skeletal muscle. Perturbation of these neural circuits and consequent loss of both UMNs and LMNs, leading to muscle wastage and impaired movement, is the key pathophysiology observed. Despite decades of research, we are still lacking in ALS disease-modifying treatments. In this review, we document the current research from patient studies, rodent models, and human stem cell models in understanding the mechanisms of corticomotor circuit dysfunction and its implication in ALS. We summarize the current knowledge about cortical UMN dysfunction and degeneration, altered excitability in LMNs, neuromuscular junction degeneration, and the non-cell autonomous role of glial cells in motor circuit dysfunction in relation to ALS. We further highlight the advances in human stem cell technology to model the complex neural circuitry and how these can aid in future studies to better understand the mechanisms of neural circuit dysfunction underpinning ALS.
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Affiliation(s)
- Andrea Salzinger
- UK Dementia Research Institute, University of Edinburgh, Edinburgh EH16 4SB, UK; (A.S.); (V.R.); (S.D.S.); (S.C.)
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Vidya Ramesh
- UK Dementia Research Institute, University of Edinburgh, Edinburgh EH16 4SB, UK; (A.S.); (V.R.); (S.D.S.); (S.C.)
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Shreya Das Sharma
- UK Dementia Research Institute, University of Edinburgh, Edinburgh EH16 4SB, UK; (A.S.); (V.R.); (S.D.S.); (S.C.)
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Siddharthan Chandran
- UK Dementia Research Institute, University of Edinburgh, Edinburgh EH16 4SB, UK; (A.S.); (V.R.); (S.D.S.); (S.C.)
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
- Anne Rowling Regenerative Neurology Clinic (ARRNC), University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Bhuvaneish Thangaraj Selvaraj
- UK Dementia Research Institute, University of Edinburgh, Edinburgh EH16 4SB, UK; (A.S.); (V.R.); (S.D.S.); (S.C.)
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
- Anne Rowling Regenerative Neurology Clinic (ARRNC), University of Edinburgh, Edinburgh EH16 4SB, UK
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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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7
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Lundt S, Zhang N, Polo-Parada L, Wang X, Ding S. Dietary NMN supplementation enhances motor and NMJ function in ALS. Exp Neurol 2024; 374:114698. [PMID: 38266764 DOI: 10.1016/j.expneurol.2024.114698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/15/2024] [Accepted: 01/20/2024] [Indexed: 01/26/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease that causes the degeneration of motor neurons in the motor cortex and spinal cord. Patients with ALS experience muscle weakness and atrophy in the limbs which eventually leads to paralysis and death. NAD+ is critical for energy metabolism, such as glycolysis and oxidative phosphorylation, but is also involved in non-metabolic cellular reactions. In the current study, we determined whether the supplementation of nicotinamide mononucleotide (NMN), an NAD+ precursor, in the diet had beneficial impacts on disease progression using a SOD1G93A mouse model of ALS. We found that the ALS mice fed with an NMN-supplemented diet (ALS+NMN mice) had modestly extended lifespan and exhibited delayed motor dysfunction. Using electrophysiology, we studied the effect of NMN on synaptic transmission at neuromuscular junctions (NMJs) in symptomatic of ALS mice (18 weeks old). ALS+NMN mice had larger end-plate potential (EPP) amplitudes and maintained better responses than ALS mice, and also had restored EPP facilitation. While quantal content was not affected by NMN, miniature EPP (mEPP) amplitude and frequency were elevated in ALS+NMN mice. NMN supplementation in diet also improved NMJ morphology, innervation, mitochondrial structure, and reduced reactive astrogliosis in the ventral horn of the lumbar spinal cord. Overall, our results indicate that dietary consumption of NMN can slow motor impairment, enhance NMJ function and improve healthspan of ALS mice.
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Affiliation(s)
- Samuel Lundt
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO 65211, United States of America; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, United States of America
| | - Nannan Zhang
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, United States of America
| | - Luis Polo-Parada
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, United States of America; Department of Medical, Physiology and Pharmacology, University of Missouri, Columbia, MO 65211, United States of America
| | - Xinglong Wang
- Department of Pharmacology & Toxicology, University of Arizona, Tucson, AZ 85721, United States of America
| | - Shinghua Ding
- Interdisciplinary Neuroscience Program, University of Missouri, Columbia, MO 65211, United States of America; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, United States of America; Department of Chemical and Biomedical Engineering, University of Missouri, Columbia, MO 65211, United States of America.
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Markovinovic A, Martín-Guerrero SM, Mórotz GM, Salam S, Gomez-Suaga P, Paillusson S, Greig J, Lee Y, Mitchell JC, Noble W, Miller CCJ. Stimulating VAPB-PTPIP51 ER-mitochondria tethering corrects FTD/ALS mutant TDP43 linked Ca 2+ and synaptic defects. Acta Neuropathol Commun 2024; 12:32. [PMID: 38395965 PMCID: PMC10885568 DOI: 10.1186/s40478-024-01742-x] [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: 09/20/2023] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are clinically linked major neurodegenerative diseases. Notably, TAR DNA-binding protein-43 (TDP43) accumulations are hallmark pathologies of FTD/ALS and mutations in the gene encoding TDP43 cause familial FTD/ALS. There are no cures for FTD/ALS. FTD/ALS display damage to a broad range of physiological functions, many of which are regulated by signaling between the endoplasmic reticulum (ER) and mitochondria. This signaling is mediated by the VAPB-PTPIP51 tethering proteins that serve to recruit regions of ER to the mitochondrial surface so as to facilitate inter-organelle communications. Several studies have now shown that disrupted ER-mitochondria signaling including breaking of the VAPB-PTPIP51 tethers are features of FTD/ALS and that for TDP43 and other familial genetic FTD/ALS insults, this involves activation of glycogen kinase-3β (GSK3β). Such findings have prompted suggestions that correcting damage to ER-mitochondria signaling and the VAPB-PTPIP51 interaction may be broadly therapeutic. Here we provide evidence to support this notion. We show that overexpression of VAPB or PTPIP51 to enhance ER-mitochondria signaling corrects mutant TDP43 induced damage to inositol 1,4,5-trisphosphate (IP3) receptor delivery of Ca2+ to mitochondria which is a primary function of the VAPB-PTPIP51 tethers, and to synaptic function. Moreover, we show that ursodeoxycholic acid (UDCA), an FDA approved drug linked to FTD/ALS and other neurodegenerative diseases therapy and whose precise therapeutic target is unclear, corrects TDP43 linked damage to the VAPB-PTPIP51 interaction. We also show that this effect involves inhibition of TDP43 mediated activation of GSK3β. Thus, correcting damage to the VAPB-PTPIP51 tethers may have therapeutic value for FTD/ALS and other age-related neurodegenerative diseases.
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Affiliation(s)
- Andrea Markovinovic
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK.
| | - Sandra M Martín-Guerrero
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Gábor M Mórotz
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Shaakir Salam
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Patricia Gomez-Suaga
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Sebastien Paillusson
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Jenny Greig
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Younbok Lee
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Jacqueline C Mitchell
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Christopher C J Miller
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK.
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Villavicencio-Tejo F, Olesen MA, Navarro L, Calisto N, Iribarren C, García K, Corsini G, Quintanilla RA. Gut-Brain Axis Deregulation and Its Possible Contribution to Neurodegenerative Disorders. Neurotox Res 2023; 42:4. [PMID: 38103074 DOI: 10.1007/s12640-023-00681-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 11/10/2023] [Accepted: 12/07/2023] [Indexed: 12/17/2023]
Abstract
The gut-brain axis is an essential communication pathway between the central nervous system (CNS) and the gastrointestinal tract. The human microbiota is composed of a diverse and abundant microbial community that compasses more than 100 trillion microorganisms that participate in relevant physiological functions such as host nutrient metabolism, structural integrity, maintenance of the gut mucosal barrier, and immunomodulation. Recent evidence in animal models has been instrumental in demonstrating the possible role of the microbiota in neurodevelopment, neuroinflammation, and behavior. Furthermore, clinical studies suggested that adverse changes in the microbiota can be considered a susceptibility factor for neurological disorders (NDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). In this review, we will discuss evidence describing the role of gut microbes in health and disease as a relevant risk factor in the pathogenesis of neurodegenerative disorders, including AD, PD, HD, and ALS.
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Affiliation(s)
- Francisca Villavicencio-Tejo
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, 5to Piso, San Miguel 8910060, Santiago, Chile
| | - Margrethe A Olesen
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, 5to Piso, San Miguel 8910060, Santiago, Chile
| | - Laura Navarro
- Laboratorio de Microbiología Molecular y Compuestos Bioactivos, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Nancy Calisto
- Laboratorio de Microbiología Molecular y Compuestos Bioactivos, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Cristian Iribarren
- Laboratorio de Patógenos Gastrointestinales, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Katherine García
- Laboratorio de Patógenos Gastrointestinales, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Gino Corsini
- Laboratorio de Microbiología Molecular y Compuestos Bioactivos, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Rodrigo A Quintanilla
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de La Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, El Llano Subercaseaux 2801, 5to Piso, San Miguel 8910060, Santiago, Chile.
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Sahota VK, Stone A, Woodling NS, Spiers JG, Steinert JR, Partridge L, Augustin H. Plum modulates Myoglianin and regulates synaptic function in D. melanogaster. Open Biol 2023; 13:230171. [PMID: 37699519 PMCID: PMC10497343 DOI: 10.1098/rsob.230171] [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: 06/03/2023] [Accepted: 08/14/2023] [Indexed: 09/14/2023] Open
Abstract
Alterations in the neuromuscular system underlie several neuromuscular diseases and play critical roles in the development of sarcopenia, the age-related loss of muscle mass and function. Mammalian Myostatin (MST) and GDF11, members of the TGF-β superfamily of growth factors, are powerful regulators of muscle size in both model organisms and humans. Myoglianin (MYO), the Drosophila homologue of MST and GDF11, is a strong inhibitor of synaptic function and structure at the neuromuscular junction in flies. Here, we identified Plum, a transmembrane cell surface protein, as a modulator of MYO function in the larval neuromuscular system. Reduction of Plum in the larval body-wall muscles abolishes the previously demonstrated positive effect of attenuated MYO signalling on both muscle size and neuromuscular junction structure and function. In addition, downregulation of Plum on its own results in decreased synaptic strength and body weight, classifying Plum as a (novel) regulator of neuromuscular function and body (muscle) size. These findings offer new insights into possible regulatory mechanisms behind ageing- and disease-related neuromuscular dysfunctions in humans and identify potential targets for therapeutic interventions.
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Affiliation(s)
- Virender K. Sahota
- Department of Biological Sciences, Centre for Biomedical Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Aelfwin Stone
- Faculty of Medicine & Health Sciences, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Nathaniel S. Woodling
- Department of Biological Sciences, Centre for Biomedical Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Jereme G. Spiers
- Faculty of Medicine & Health Sciences, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Joern R. Steinert
- Faculty of Medicine & Health Sciences, Queen's Medical Centre, Nottingham NG7 2UH, UK
| | - Linda Partridge
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne 50931, Germany
| | - Hrvoje Augustin
- Department of Biological Sciences, Centre for Biomedical Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
- Institute of Healthy Ageing, and GEE, University College London, Darwin Building, Gower Street, London WC1E 6BT, UK
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Str. 9b, Cologne 50931, Germany
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11
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Piol D, Robberechts T, Da Cruz S. Lost in local translation: TDP-43 and FUS in axonal/neuromuscular junction maintenance and dysregulation in amyotrophic lateral sclerosis. Neuron 2023; 111:1355-1380. [PMID: 36963381 DOI: 10.1016/j.neuron.2023.02.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/21/2022] [Accepted: 02/16/2023] [Indexed: 03/26/2023]
Abstract
Key early features of amyotrophic lateral sclerosis (ALS) are denervation of neuromuscular junctions and axonal degeneration. Motor neuron homeostasis relies on local translation through controlled regulation of axonal mRNA localization, transport, and stability. Yet the composition of the local transcriptome, translatome (mRNAs locally translated), and proteome during health and disease remains largely unexplored. This review covers recent discoveries on axonal translation as a critical mechanism for neuronal maintenance/survival. We focus on two RNA binding proteins, transactive response DNA binding protein-43 (TDP-43) and fused in sarcoma (FUS), whose mutations cause ALS and frontotemporal dementia (FTD). Emerging evidence points to their essential role in the maintenance of axons and synapses, including mRNA localization, transport, and local translation, and whose dysfunction may contribute to ALS. Finally, we describe recent advances in omics-based approaches mapping compartment-specific local RNA and protein compositions, which will be invaluable to elucidate fundamental local processes and identify key targets for therapy development.
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Affiliation(s)
- Diana Piol
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium
| | - Tessa Robberechts
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium
| | - Sandrine Da Cruz
- VIB-KU Leuven Center for Brain and Disease Research, Department of Neurosciences, KU Leuven, Leuven Brain Institute, Leuven, Belgium.
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12
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Tu WY, Xu W, Zhang J, Qi S, Bai L, Shen C, Zhang K. C9orf72 poly-GA proteins impair neuromuscular transmission. Zool Res 2023; 44:331-340. [PMID: 36799225 PMCID: PMC10083233 DOI: 10.24272/j.issn.2095-8137.2022.356] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/15/2023] [Indexed: 02/18/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating motoneuron disease, in which lower motoneurons lose control of skeletal muscles. Degeneration of neuromuscular junctions (NMJs) occurs at the initial stage of ALS. Dipeptide repeat proteins (DPRs) from G4C2 repeat-associated non-ATG (RAN) translation are known to cause C9orf72-associated ALS (C9-ALS). However, DPR inclusion burdens are weakly correlated with neurodegenerative areas in C9-ALS patients, indicating that DPRs may exert cell non-autonomous effects, in addition to the known intracellular pathological mechanisms. Here, we report that poly-GA, the most abundant form of DPR in C9-ALS, is released from cells. Local administration of poly-GA proteins in peripheral synaptic regions causes muscle weakness and impaired neuromuscular transmission in vivo. The NMJ structure cannot be maintained, as evidenced by the fragmentation of postsynaptic acetylcholine receptor (AChR) clusters and distortion of presynaptic nerve terminals. Mechanistic study demonstrated that extracellular poly-GA sequesters soluble Agrin ligands and inhibits Agrin-MuSK signaling. Our findings provide a novel cell non-autonomous mechanism by which poly-GA impairs NMJs in C9-ALS. Thus, targeting NMJs could be an early therapeutic intervention for C9-ALS.
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Affiliation(s)
- Wen-Yo Tu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Wentao Xu
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Jianmin Zhang
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Shuyuan Qi
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Lei Bai
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
| | - Chengyong Shen
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China
- MOE Frontier Science, Center for Brain Research and Brain-Machine Integration, Zhejiang University, Hangzhou, Zhejiang 310058, China. E-mail:
| | - Kejing Zhang
- Zhejiang Provincial Key Laboratory of Pancreatic Disease, Department of Neurobiology, First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310020, China. E-mail:
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13
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Robbins M, Clayton EL. Synaptopathy in CHMP2B frontotemporal dementia highlights the synaptic vesicle cycle as a therapeutic target. Neural Regen Res 2023; 18:315-316. [PMID: 35900412 PMCID: PMC9396515 DOI: 10.4103/1673-5374.343905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Miranda Robbins
- MRC Laboratory of Molecular Biology; Department of Zoology, University of Cambridge, Cambridge, UK
| | - Emma L Clayton
- UK Dementia Research Institute at King's College London; Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Maurice Wohl Clinical Neuroscience Institute, London, UK
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14
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Lépine S, Castellanos-Montiel MJ, Durcan TM. TDP-43 dysregulation and neuromuscular junction disruption in amyotrophic lateral sclerosis. Transl Neurodegener 2022; 11:56. [PMID: 36575535 PMCID: PMC9793560 DOI: 10.1186/s40035-022-00331-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 11/29/2022] [Indexed: 12/28/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a disease characterized by upper and lower motor neuron (MN) loss with a signature feature of cytoplasmic aggregates containing TDP-43, which are detected in nearly all patients. Mutations in the gene that encodes TDP-43 (TARBDP) are known to result in both familial and sporadic ALS. In ALS, disruption of neuromuscular junctions (NMJs) constitutes a critical event in disease pathogenesis, leading to denervation atrophy, motor impairments and disability. Morphological defects and impaired synaptic transmission at NMJs have been reported in several TDP-43 animal models and in vitro, linking TDP-43 dysregulation to the loss of NMJ integrity in ALS. Through the lens of the dying-back and dying-forward hypotheses of ALS, this review discusses the roles of TDP-43 related to synaptic function, with a focus on the potential molecular mechanisms occurring within MNs, skeletal muscles and glial cells that may contribute to NMJ disruption in ALS.
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Affiliation(s)
- Sarah Lépine
- grid.14709.3b0000 0004 1936 8649The Neuro’s Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, 3801 University Street, Montreal, QC H3A 2B4 Canada ,grid.14709.3b0000 0004 1936 8649Faculty of Medicine and Health Sciences, McGill University, 3605 De La Montagne, Montreal, QC H3G 2M1 Canada
| | - Maria José Castellanos-Montiel
- grid.14709.3b0000 0004 1936 8649The Neuro’s Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, 3801 University Street, Montreal, QC H3A 2B4 Canada
| | - Thomas Martin Durcan
- grid.14709.3b0000 0004 1936 8649The Neuro’s Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, 3801 University Street, Montreal, QC H3A 2B4 Canada
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15
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De Carvalho M, Swash M. Transcranial magnetic stimulation to monitor disease progression in ALS: a review. Amyotroph Lateral Scler Frontotemporal Degener 2022. [DOI: 10.1080/21678421.2022.2160649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Mamede De Carvalho
- Instituto de Fisiologia, Instituto de Medicina Molecular, Centro de Estudos Egas Moniz, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Department of Neurosciences and Mental Health, Centro Hospitalar Universitário Lisboa Norte, Lisboa, Portugal, and
| | - Michael Swash
- Instituto de Fisiologia, Instituto de Medicina Molecular, Centro de Estudos Egas Moniz, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Barts and the London School of Medicine, Queen Mary University of London, UK
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16
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Badiola-Mateos M, Osaki T, Kamm RD, Samitier J. In vitro modelling of human proprioceptive sensory neurons in the neuromuscular system. Sci Rep 2022; 12:21318. [PMID: 36494423 PMCID: PMC9734133 DOI: 10.1038/s41598-022-23565-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 11/02/2022] [Indexed: 12/13/2022] Open
Abstract
Proprioceptive sensory neurons (pSN) are an essential and undervalued part of the neuromuscular circuit. A protocol to differentiate healthy and amyotrophic lateral sclerosis (ALS) human neural stem cells (hNSC) into pSN, and their comparison with the motor neuron (MN) differentiation process from the same hNSC sources, facilitated the development of in vitro co-culture platforms. The obtained pSN spheroids cultured interact with human skeletal myocytes showing the formation of annulospiral wrapping-like structures between TrkC + neurons and a multinucleated muscle fibre, presenting synaptic bouton-like structures in the contact point. The comparative analysis of the genetic profile performed in healthy and sporadic ALS hNSC differentiated to pSN suggested that basal levels of ETV1, critical for motor feedback from pSN, were much lower for ALS samples and that the differences between healthy and ALS samples, suggest the involvement of pSN in ALS pathology development and progression.
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Affiliation(s)
- Maider Badiola-Mateos
- grid.424736.00000 0004 0536 2369Institute for Bioengineering of Catalonia (IBEC)—Barcelona Institute of Science and Technology, 08028 Barcelona, Spain ,grid.5841.80000 0004 1937 0247Department of Electronic and Biomedical Engineering, Universitat de Barcelona, 08028 Barcelona, Spain ,grid.116068.80000 0001 2341 2786Department of Biological Engineering, Massachusetts Institute of Technology (MIT), 500 Technology Square, MIT Building, Cambridge, MA 02139 USA ,grid.263145.70000 0004 1762 600XPresent Address: The BioRobotics Institute, Department of Excellence in Robotics and AI, Scuola Superiore Sant’Anna, 56127 Pisa, Italy
| | - Tatsuya Osaki
- grid.116068.80000 0001 2341 2786Department of Biological Engineering, Massachusetts Institute of Technology (MIT), 500 Technology Square, MIT Building, Cambridge, MA 02139 USA ,grid.26999.3d0000 0001 2151 536XPresent Address: Institute of Industrial Science, The University of Tokyo, 4-6-1, Komaba, Meguro-Ku, Tokyo, 153-8505 Japan
| | - Roger Dale Kamm
- grid.116068.80000 0001 2341 2786Department of Biological Engineering, Massachusetts Institute of Technology (MIT), 500 Technology Square, MIT Building, Cambridge, MA 02139 USA ,grid.116068.80000 0001 2341 2786Department of Mechanical Engineering, Massachusetts Institute of Technology, 500 Technology Square, MIT Building, Cambridge, MA 02139 USA
| | - Josep Samitier
- grid.424736.00000 0004 0536 2369Institute for Bioengineering of Catalonia (IBEC)—Barcelona Institute of Science and Technology, 08028 Barcelona, Spain ,grid.5841.80000 0004 1937 0247Department of Electronic and Biomedical Engineering, Universitat de Barcelona, 08028 Barcelona, Spain ,grid.512890.7Centro de Investigación Biomédica en Red (CIBER-BBN), 28029 Madrid, Spain
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17
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Gelon PA, Dutchak PA, Sephton CF. Synaptic dysfunction in ALS and FTD: anatomical and molecular changes provide insights into mechanisms of disease. Front Mol Neurosci 2022; 15:1000183. [PMID: 36263379 PMCID: PMC9575515 DOI: 10.3389/fnmol.2022.1000183] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 09/01/2022] [Indexed: 11/29/2022] Open
Abstract
Synaptic loss is a pathological feature of all neurodegenerative diseases including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). ALS is a disease of the cortical and spinal motor neurons resulting in fatal paralysis due to denervation of muscles. FTD is a form of dementia that primarily affects brain regions controlling cognition, language and behavior. Once classified as two distinct diseases, ALS and FTD are now considered as part of a common disease spectrum based on overlapping clinical, pathological and genetic evidence. At the cellular level, aggregation of common proteins and overlapping gene susceptibilities are shared in both ALS and FTD. Despite the convergence of these two fields of research, the underlying disease mechanisms remain elusive. However, recent discovers from ALS and FTD patient studies and models of ALS/FTD strongly suggests that synaptic dysfunction is an early event in the disease process and a unifying hallmark of these diseases. This review provides a summary of the reported anatomical and cellular changes that occur in cortical and spinal motor neurons in ALS and FTD tissues and models of disease. We also highlight studies that identify changes in the proteome and transcriptome of ALS and FTD models and provide a conceptual overview of the processes that contribute to synaptic dysfunction in these diseases. Due to space limitations and the vast number of publications in the ALS and FTD fields, many articles have not been discussed in this review. As such, this review focuses on the three most common shared mutations in ALS and FTD, the hexanucleuotide repeat expansion within intron 1 of chromosome 9 open reading frame 72 (C9ORF72), transactive response DNA binding protein 43 (TARDBP or TDP-43) and fused in sarcoma (FUS), with the intention of highlighting common pathways that promote synaptic dysfunction in the ALS-FTD disease spectrum.
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18
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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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19
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Davis LA, Fogarty MJ, Brown A, Sieck GC. Structure and Function of the Mammalian Neuromuscular Junction. Compr Physiol 2022; 12:3731-3766. [PMID: 35950651 PMCID: PMC10461538 DOI: 10.1002/cphy.c210022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The mammalian neuromuscular junction (NMJ) comprises a presynaptic terminal, a postsynaptic receptor region on the muscle fiber (endplate), and the perisynaptic (terminal) Schwann cell. As with any synapse, the purpose of the NMJ is to transmit signals from the nervous system to muscle fibers. This neural control of muscle fibers is organized as motor units, which display distinct structural and functional phenotypes including differences in pre- and postsynaptic elements of NMJs. Motor units vary considerably in the frequency of their activation (both motor neuron discharge rate and duration/duty cycle), force generation, and susceptibility to fatigue. For earlier and more frequently recruited motor units, the structure and function of the activated NMJs must have high fidelity to ensure consistent activation and continued contractile response to sustain vital motor behaviors (e.g., breathing and postural balance). Similarly, for higher force less frequent behaviors (e.g., coughing and jumping), the structure and function of recruited NMJs must ensure short-term reliable activation but not activation sustained for a prolonged period in which fatigue may occur. The NMJ is highly plastic, changing structurally and functionally throughout the life span from embryonic development to old age. The NMJ also changes under pathological conditions including acute and chronic disease. Such neuroplasticity often varies across motor unit types. © 2022 American Physiological Society. Compr Physiol 12:1-36, 2022.
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Affiliation(s)
- Leah A. Davis
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew J. Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Alyssa Brown
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Gary C. Sieck
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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20
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Lum JS, Berg T, Chisholm CG, Vendruscolo M, Yerbury JJ. Vulnerability of the spinal motor neuron presynaptic terminal sub-proteome in ALS. Neurosci Lett 2022; 778:136614. [PMID: 35367314 DOI: 10.1016/j.neulet.2022.136614] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 03/29/2022] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder, characterised by the loss of motor neurons and subsequent paralysis. Evidence indicates that synaptic alterations are associated with the early stages of ALS pathogenesis. A hallmark of ALS postmortem tissue is the presence of proteinaceous inclusions, indicative of disturbed protein homeostasis, particularly in spinal cord motor neurons. We recently demonstrated that spinal cord motor neurons contain a supersaturated proteome, as they possess proteins at concentrations that exceed their solubility limits, resulting in a metastable proteome conducive to protein misfolding and aggregation. Recent evidence indicates metastable sub-proteomes within neuronal compartments, such as the synapse, may be particularly vulnerable and underlie their involvement in the initial stages of neurodegenerative diseases. To investigate if the motor neuron presynaptic terminal possesses a metastable sub-proteome, we used human and mouse spinal cord motor neuron expression data to calculate supersaturation scores. Here, we found that both the human and mouse presynaptic terminal sub-proteomes have higher supersaturation scores than the entire motor neuron proteome. In addition, we observed that proteins down-regulated in ALS were over-represented in the synapse. These results provide support for the notion that the metastability of the sub-proteome within the motor neuron presynaptic terminal may be particularly susceptible to protein homeostasis disturbances in ALS, and may contribute to explaining the observed synaptic dysfunction in ALS.
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Affiliation(s)
- Jeremy S Lum
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Tracey Berg
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Christen G Chisholm
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Justin J Yerbury
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
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21
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Alteration of the Neuromuscular Junction and Modifications of Muscle Metabolism in Response to Neuron-Restricted Expression of the CHMP2Bintron5 Mutant in a Mouse Model of ALS-FTD Syndrome. Biomolecules 2022; 12:biom12040497. [PMID: 35454086 PMCID: PMC9025139 DOI: 10.3390/biom12040497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/12/2022] [Accepted: 03/21/2022] [Indexed: 02/04/2023] Open
Abstract
CHMP2B is a protein that coordinates membrane scission events as a core component of the ESCRT machinery. Mutations in CHMP2B are an uncommon cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), two neurodegenerative diseases with clinical, genetic, and pathological overlap. Different mutations have now been identified across the ALS-FTD spectrum. Disruption of the neuromuscular junction is an early pathogenic event in ALS. Currently, the links between neuromuscular junction functionality and ALS-associated genes, such as CHMP2B, remain poorly understood. We have previously shown that CHMP2B transgenic mice expressing the CHMP2Bintron5 mutant specifically in neurons develop a progressive motor phenotype reminiscent of ALS. In this study, we used complementary approaches (behavior, histology, electroneuromyography, and biochemistry) to determine the extent to which neuron-specific expression of CHMP2Bintron5 could impact the skeletal muscle characteristics. We show that neuronal expression of the CHMP2Bintron5 mutant is sufficient to trigger progressive gait impairment associated with structural and functional changes in the neuromuscular junction. Indeed, CHMP2Bintron5 alters the pre-synaptic terminal organization and the synaptic transmission that ultimately lead to a switch of fast-twitch glycolytic muscle fibers to more oxidative slow-twitch muscle fibers. Taken together these data indicate that neuronal expression of CHMP2Bintron5 is sufficient to induce a synaptopathy with molecular and functional changes in the motor unit reminiscent of those found in ALS patients.
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22
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Verma S, Khurana S, Vats A, Sahu B, Ganguly NK, Chakraborti P, Gourie-Devi M, Taneja V. Neuromuscular Junction Dysfunction in Amyotrophic Lateral Sclerosis. Mol Neurobiol 2022; 59:1502-1527. [PMID: 34997540 DOI: 10.1007/s12035-021-02658-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 11/18/2021] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurological disorder characterized by progressive degeneration of motor neurons leading to skeletal muscle denervation. Earlier studies have shown that motor neuron degeneration begins in motor cortex and descends to the neuromuscular junction (NMJ) in a dying forward fashion. However, accumulating evidences support that ALS is a distal axonopathy where early pathological changes occur at the NMJ, prior to onset of clinical symptoms and propagates towards the motor neuron cell body supporting "dying back" hypothesis. Despite several evidences, series of events triggering NMJ disassembly in ALS are still obscure. Neuromuscular junction is a specialized tripartite chemical synapse which involves a well-coordinated communication among the presynaptic motor neuron, postsynaptic skeletal muscle, and terminal Schwann cells. This review provides comprehensive insight into the role of NMJ in ALS pathogenesis. We have emphasized the molecular alterations in cellular components of NMJ leading to loss of effective neuromuscular transmission in ALS. Further, we provide a preview into research involved in exploring NMJ as potential target for designing effective therapies for ALS.
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Affiliation(s)
- Sagar Verma
- Department of Research, Sir Ganga Ram Hospital, Delhi, India.,Department of Biotechnology, Jamia Hamdard, Delhi, India
| | - Shiffali Khurana
- Department of Research, Sir Ganga Ram Hospital, Delhi, India.,Department of Biomedical Science, Bhaskaracharya College of Applied Sciences, University of Delhi, Delhi, India
| | - Abhishek Vats
- Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bandana Sahu
- Department of Research, Sir Ganga Ram Hospital, Delhi, India
| | | | | | | | - Vibha Taneja
- Department of Research, Sir Ganga Ram Hospital, Delhi, India.
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23
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The Neuromuscular Junction: Roles in Aging and Neuromuscular Disease. Int J Mol Sci 2021; 22:ijms22158058. [PMID: 34360831 PMCID: PMC8347593 DOI: 10.3390/ijms22158058] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 02/07/2023] Open
Abstract
The neuromuscular junction (NMJ) is a specialized synapse that bridges the motor neuron and the skeletal muscle fiber and is crucial for conversion of electrical impulses originating in the motor neuron to action potentials in the muscle fiber. The consideration of contributing factors to skeletal muscle injury, muscular dystrophy and sarcopenia cannot be restricted only to processes intrinsic to the muscle, as data show that these conditions incur denervation-like findings, such as fragmented NMJ morphology and corresponding functional changes in neuromuscular transmission. Primary defects in the NMJ also influence functional loss in motor neuron disease, congenital myasthenic syndromes and myasthenia gravis, resulting in skeletal muscle weakness and heightened fatigue. Such findings underscore the role that the NMJ plays in neuromuscular performance. Regardless of cause or effect, functional denervation is now an accepted consequence of sarcopenia and muscle disease. In this short review, we provide an overview of the pathologic etiology, symptoms, and therapeutic strategies related to the NMJ. In particular, we examine the role of the NMJ as a disease modifier and a potential therapeutic target in neuromuscular injury and disease.
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24
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Pikatza-Menoio O, Elicegui A, Bengoetxea X, Naldaiz-Gastesi N, López de Munain A, Gerenu G, Gil-Bea FJ, Alonso-Martín S. The Skeletal Muscle Emerges as a New Disease Target in Amyotrophic Lateral Sclerosis. J Pers Med 2021; 11:671. [PMID: 34357138 PMCID: PMC8307751 DOI: 10.3390/jpm11070671] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/09/2021] [Accepted: 07/14/2021] [Indexed: 01/02/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons (MNs) and severe muscle atrophy without effective treatment. Most research on ALS has been focused on the study of MNs and supporting cells of the central nervous system. Strikingly, the recent observations of pathological changes in muscle occurring before disease onset and independent from MN degeneration have bolstered the interest for the study of muscle tissue as a potential target for delivery of therapies for ALS. Skeletal muscle has just been described as a tissue with an important secretory function that is toxic to MNs in the context of ALS. Moreover, a fine-tuning balance between biosynthetic and atrophic pathways is necessary to induce myogenesis for muscle tissue repair. Compromising this response due to primary metabolic abnormalities in the muscle could trigger defective muscle regeneration and neuromuscular junction restoration, with deleterious consequences for MNs and thereby hastening the development of ALS. However, it remains puzzling how backward signaling from the muscle could impinge on MN death. This review provides a comprehensive analysis on the current state-of-the-art of the role of the skeletal muscle in ALS, highlighting its contribution to the neurodegeneration in ALS through backward-signaling processes as a newly uncovered mechanism for a peripheral etiopathogenesis of the disease.
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Affiliation(s)
- Oihane Pikatza-Menoio
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
| | - Amaia Elicegui
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
| | - Xabier Bengoetxea
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
| | - Neia Naldaiz-Gastesi
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
| | - Adolfo López de Munain
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
- Department of Neurology, Donostialdea Integrated Health Organization, Osakidetza Basque Health Service, 20014 Donostia/San Sebastián, Spain
- Department of Neurosciences, Faculty of Medicine and Nursery, University of the Basque Country UPV-EHU, 20014 Donostia/San Sebastián, Spain
| | - Gorka Gerenu
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
- Department of Physiology, University of the Basque Country UPV-EHU, 48940 Leioa, Spain
| | - Francisco Javier Gil-Bea
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
| | - Sonia Alonso-Martín
- Neuromuscular Diseases Group, Neurosciences Area, Biodonostia Health Research Institute, 20014 Donostia/San Sebastián, Spain; (O.P.-M.); (A.E.); (X.B.); (N.N.-G.); (A.L.d.M.); (G.G.); (F.J.G.-B.)
- CIBERNED, Carlos III Institute, Spanish Ministry of Economy & Competitiveness, 28031 Madrid, Spain
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25
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Alhindi A, Boehm I, Chaytow H. Small junction, big problems: Neuromuscular junction pathology in mouse models of amyotrophic lateral sclerosis (ALS). J Anat 2021; 241:1089-1107. [PMID: 34101196 PMCID: PMC9558162 DOI: 10.1111/joa.13463] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 01/31/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a motor neuron disease with an extremely heterogeneous clinical and genetic phenotype. In our efforts to find therapies for ALS, the scientific community has developed a plethora of mouse models, each with their own benefits and drawbacks. The peripheral nervous system, specifically the neuromuscular junction (NMJ), is known to be affected in ALS patients and shows marked dysfunction across mouse models. Evidence of pathology at the NMJ includes denervated NMJs, changes in endplate size and loss of terminal Schwann cells. This review compares the temporal disease progression with severity of disease at the NMJ in mouse models with the most commonly mutated genes in ALS patients (SOD1, C9ORF72, TARDBP and FUS). Despite variability, early NMJ dysfunction seems to be a common factor in models with SOD1, TARDBP and FUS mutations, while C9ORF72 models do not appear to follow the same pattern of pathology. Further work into determining the timing of NMJ pathology, particularly in newer ALS mouse models, will confirm its pivotal role in ALS pathogenesis and therefore highlight the NMJ as a potential therapeutic target.
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Affiliation(s)
- Abrar Alhindi
- Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Department of Anatomy, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Ines Boehm
- Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Helena Chaytow
- Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
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26
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Zebrafish, an In Vivo Platform to Screen Drugs and Proteins for Biomedical Use. Pharmaceuticals (Basel) 2021; 14:ph14060500. [PMID: 34073947 PMCID: PMC8225009 DOI: 10.3390/ph14060500] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/14/2021] [Accepted: 05/20/2021] [Indexed: 12/28/2022] Open
Abstract
The nearly simultaneous convergence of human genetics and advanced molecular technologies has led to an improved understanding of human diseases. At the same time, the demand for drug screening and gene function identification has also increased, albeit time- and labor-intensive. However, bridging the gap between in vitro evidence from cell lines and in vivo evidence, the lower vertebrate zebrafish possesses many advantages over higher vertebrates, such as low maintenance, high fecundity, light-induced spawning, transparent embryos, short generation interval, rapid embryonic development, fully sequenced genome, and some phenotypes similar to human diseases. Such merits have popularized the zebrafish as a model system for biomedical and pharmaceutical studies, including drug screening. Here, we reviewed the various ways in which zebrafish serve as an in vivo platform to perform drug and protein screening in the fields of rare human diseases, social behavior and cancer studies. Since zebrafish mutations faithfully phenocopy many human disorders, many compounds identified from zebrafish screening systems have advanced to early clinical trials, such as those for Adenoid cystic carcinoma, Dravet syndrome and Diamond-Blackfan anemia. We also reviewed and described how zebrafish are used to carry out environmental pollutant detection and assessment of nanoparticle biosafety and QT prolongation.
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27
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Molecular Mechanisms Underlying TDP-43 Pathology in Cellular and Animal Models of ALS and FTLD. Int J Mol Sci 2021; 22:ijms22094705. [PMID: 33946763 PMCID: PMC8125728 DOI: 10.3390/ijms22094705] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/22/2021] [Accepted: 04/28/2021] [Indexed: 02/03/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are neurodegenerative disorders that exist on a disease spectrum due to pathological, clinical and genetic overlap. In up to 97% of ALS cases and ~50% of FTLD cases, the primary pathological protein observed in affected tissues is TDP-43, which is hyperphosphorylated, ubiquitinated and cleaved. The TDP-43 is observed in aggregates that are abnormally located in the cytoplasm. The pathogenicity of TDP-43 cytoplasmic aggregates may be linked with both a loss of nuclear function and a gain of toxic functions. The cellular processes involved in ALS and FTLD disease pathogenesis include changes to RNA splicing, abnormal stress granules, mitochondrial dysfunction, impairments to axonal transport and autophagy, abnormal neuromuscular junctions, endoplasmic reticulum stress and the subsequent induction of the unfolded protein response. Here, we review and discuss the evidence for alterations to these processes that have been reported in cellular and animal models of TDP-43 proteinopathy.
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28
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Russo K, Wharton KA. BMP/TGF-β signaling as a modulator of neurodegeneration in ALS. Dev Dyn 2021; 251:10-25. [PMID: 33745185 DOI: 10.1002/dvdy.333] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/19/2022] Open
Abstract
This commentary focuses on the emerging intersection between BMP/TGF-β signaling roles in nervous system function and the amyotrophic lateral sclerosis (ALS) disease state. Future research is critical to elucidate the molecular underpinnings of this intersection of the cellular processes disrupted in ALS and those influenced by BMP/TGF-β signaling, including synapse structure, neurotransmission, plasticity, and neuroinflammation. Such knowledge promises to inform us of ideal entry points for the targeted modulation of dysfunctional cellular processes in an effort to abrogate ALS pathologies. It is likely that different interventions are required, either at discrete points in disease progression, or across multiple dysfunctional processes which together lead to motor neuron degeneration and death. We discuss the challenging, but intriguing idea that modulation of the pleiotropic nature of BMP/TGF-β signaling could be advantageous, as a way to simultaneously treat defects in more than one cell process across different forms of ALS.
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Affiliation(s)
- Kathryn Russo
- Department of Neuroscience, Brown University, Providence, Rhode Island, USA.,Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, USA
| | - Kristi A Wharton
- Robert J. and Nancy D. Carney Institute for Brain Science, Brown University, Providence, Rhode Island, USA.,Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, USA
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29
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de Jongh R, Spijkers XM, Pasteuning-Vuhman S, Vulto P, Pasterkamp RJ. Neuromuscular junction-on-a-chip: ALS disease modeling and read-out development in microfluidic devices. J Neurochem 2021; 157:393-412. [PMID: 33382092 DOI: 10.1111/jnc.15289] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 12/21/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disease affecting upper and lower motor neurons with no cure available. Clinical and animal studies reveal that the neuromuscular junction (NMJ), a synaptic connection between motor neurons and skeletal muscle fibers, is highly vulnerable in ALS and suggest that NMJ defects may occur at the early stages of the disease. However, mechanistic insight into how NMJ dysfunction relates to the onset and progression of ALS is incomplete, which hampers therapy development. This is, in part, caused by a lack of robust in vitro models. The ability to combine microfluidic and induced pluripotent stem cell (iPSC) technologies has opened up new avenues for studying molecular and cellular ALS phenotypes in vitro. Microfluidic devices offer several advantages over traditional culture approaches when modeling the NMJ, such as the spatial separation of different cell types and increased control over the cellular microenvironment. Moreover, they are compatible with 3D cell culture, which enhances NMJ functionality and maturity. Here, we review how microfluidic technology is currently being employed to develop more reliable in vitro NMJ models. To validate and phenotype such models, various morphological and functional read-outs have been developed. We describe and discuss the relevance of these read-outs and specifically illustrate how these read-outs have enhanced our understanding of NMJ pathology in ALS. Finally, we share our view on potential future directions and challenges.
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Affiliation(s)
- Rianne de Jongh
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Xandor M Spijkers
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.,Mimetas B.V., Organ-on-a-chip Company, Leiden, The Netherlands
| | - Svetlana Pasteuning-Vuhman
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Paul Vulto
- Mimetas B.V., Organ-on-a-chip Company, Leiden, The Netherlands
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
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30
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Buratti E. Trends in Understanding the Pathological Roles of TDP-43 and FUS Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1281:243-267. [PMID: 33433879 DOI: 10.1007/978-3-030-51140-1_15] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Following the discovery of TDP-43 and FUS involvement in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar dementia (FTLD), the major challenge in the field has been to understand their physiological functions, both in normal and disease conditions. The hope is that this knowledge will improve our understanding of disease and lead to the development of effective therapeutic options. Initially, the focus has been directed at characterizing the role of these proteins in the control of RNA metabolism, because the main function of TDP-43 and FUS is to bind coding and noncoding RNAs to regulate their life cycle within cells. As a result, we now have an in-depth picture of the alterations that occur in RNA metabolism following their aggregation in various ALS/FTLD models and, to a somewhat lesser extent, in patients' brains. In parallel, progress has been made with regard to understanding how aggregation of these proteins occurs in neurons, how it can spread in different brain regions, and how these changes affect various metabolic cellular pathways to result in neuronal death. The aim of this chapter will be to provide a general overview of the trending topics in TDP-43 and FUS investigations and to highlight what might represent the most promising avenues of research in the years to come.
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Affiliation(s)
- Emanuele Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy.
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31
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Castets P, Ham DJ, Rüegg MA. The TOR Pathway at the Neuromuscular Junction: More Than a Metabolic Player? Front Mol Neurosci 2020; 13:162. [PMID: 32982690 PMCID: PMC7485269 DOI: 10.3389/fnmol.2020.00162] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/05/2020] [Indexed: 12/18/2022] Open
Abstract
The neuromuscular junction (NMJ) is the chemical synapse connecting motor neurons and skeletal muscle fibers. NMJs allow all voluntary movements, and ensure vital functions like breathing. Changes in the structure and function of NMJs are hallmarks of numerous pathological conditions that affect muscle function including sarcopenia, the age-related loss of muscle mass and function. However, the molecular mechanisms leading to the morphological and functional perturbations in the pre- and post-synaptic compartments of the NMJ remain poorly understood. Here, we discuss the role of the metabolic pathway associated to the kinase TOR (Target of Rapamycin) in the development, maintenance and alterations of the NMJ. This is of particular interest as the TOR pathway has been implicated in aging, but its role at the NMJ is still ill-defined. We highlight the respective functions of the two TOR-associated complexes, TORC1 and TORC2, and discuss the role of localized protein synthesis and autophagy regulation in motor neuron terminals and sub-synaptic regions of muscle fibers and their possible effects on NMJ maintenance.
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Affiliation(s)
- Perrine Castets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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32
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Lee JD, McDonald TS, Fung JNT, Woodruff TM. Absence of Receptor for Advanced Glycation End Product (RAGE) Reduces Inflammation and Extends Survival in the hSOD1 G93A Mouse Model of Amyotrophic Lateral Sclerosis. Mol Neurobiol 2020; 57:4143-4155. [PMID: 32676989 DOI: 10.1007/s12035-020-02019-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/08/2020] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal and rapidly progressing motor neuron degenerative disease that is without effective treatment. The receptor for advanced glycation end products (RAGE) is a major component of the innate immune system that has been implicated in ALS pathogenesis. However, the contribution of RAGE signalling to the neuroinflammation that underlies ALS neurodegeneration remains unknown. The present study therefore generated SOD1G93A mice lacking RAGE and compared them with SOD1G93A transgenic ALS mice in respect to disease progression (i.e. body weight, survival and muscle strength), neuroinflammation and denervation markers in the spinal cord and tibialis anterior muscle. We found that complete absence of RAGE signalling exerted a protective effect on SOD1G93A pathology, slowing disease progression and significantly extending survival by ~ 3 weeks and improving motor function (rotarod and grip strength). This was associated with reduced microgliosis, cytokines, innate immune factors (complement, TLRs, inflammasomes), and oxidative stress in the spinal cord, and a reduction of denervation markers in the tibialis anterior muscle. We also documented that RAGE mRNA expression was significantly increased in the spinal cord and muscles of preclinical SOD1 and TDP43 models of ALS, supporting a widespread involvement for RAGE in ALS pathology. In summary, our results indicate that RAGE signalling drives neuroinflammation and contributes to neurodegeneration in ALS and highlights RAGE as a potential immune therapeutic target for ALS.
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Affiliation(s)
- John D Lee
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
| | - Tanya S McDonald
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
| | - Jenny N T Fung
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
| | - Trent M Woodruff
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia. .,Queensland Brain Institute, the University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.
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33
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Jensen BK, Schuldi MH, McAvoy K, Russell KA, Boehringer A, Curran BM, Krishnamurthy K, Wen X, Westergard T, Ma L, Haeusler AR, Edbauer D, Pasinelli P, Trotti D. Synaptic dysfunction induced by glycine-alanine dipeptides in C9orf72-ALS/FTD is rescued by SV2 replenishment. EMBO Mol Med 2020; 12:e10722. [PMID: 32347002 PMCID: PMC7207170 DOI: 10.15252/emmm.201910722] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 03/23/2020] [Accepted: 03/26/2020] [Indexed: 12/16/2022] Open
Abstract
The most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is an intronic hexanucleotide repeat expansion in the C9orf72 gene. In disease, RNA transcripts containing this expanded region undergo repeat-associated non-AUG translation to produce dipeptide repeat proteins (DPRs), which are detected in brain and spinal cord of patients and are neurotoxic both in vitro and in vivo paradigms. We reveal here a novel pathogenic mechanism for the most abundantly detected DPR in ALS/FTD autopsy tissues, poly-glycine-alanine (GA). Previously, we showed motor dysfunction in a GA mouse model without loss of motor neurons. Here, we demonstrate that mobile GA aggregates are present within neurites, evoke a reduction in synaptic vesicle-associated protein 2 (SV2), and alter Ca2+ influx and synaptic vesicle release. These phenotypes could be corrected by restoring SV2 levels. In GA mice, loss of SV2 was observed without reduction of motor neuron number. Notably, reduction in SV2 was seen in cortical and motor neurons derived from patient induced pluripotent stem cell lines, suggesting synaptic alterations also occur in patients.
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Affiliation(s)
- Brigid K Jensen
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Martin H Schuldi
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
| | - Kevin McAvoy
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Katelyn A Russell
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Ashley Boehringer
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Bridget M Curran
- Department of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Karthik Krishnamurthy
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Xinmei Wen
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Thomas Westergard
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Le Ma
- Department of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Aaron R Haeusler
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE)MunichGermany
| | - Piera Pasinelli
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Davide Trotti
- Jefferson Weinberg ALS CenterDepartment of NeuroscienceVickie and Jack Farber Institute for NeuroscienceThomas Jefferson UniversityPhiladelphiaPAUSA
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Presynaptic Homeostasis Opposes Disease Progression in Mouse Models of ALS-Like Degeneration: Evidence for Homeostatic Neuroprotection. Neuron 2020; 107:95-111.e6. [PMID: 32380032 DOI: 10.1016/j.neuron.2020.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 03/06/2020] [Accepted: 04/06/2020] [Indexed: 12/11/2022]
Abstract
Progressive synapse loss is an inevitable and insidious part of age-related neurodegenerative disease. Typically, synapse loss precedes symptoms of cognitive and motor decline. This suggests the existence of compensatory mechanisms that can temporarily counteract the effects of ongoing neurodegeneration. Here, we demonstrate that presynaptic homeostatic plasticity (PHP) is induced at degenerating neuromuscular junctions, mediated by an evolutionarily conserved activity of presynaptic ENaC channels in both Drosophila and mouse. To assess the consequence of eliminating PHP in a mouse model of ALS-like degeneration, we generated a motoneuron-specific deletion of Scnn1a, encoding the ENaC channel alpha subunit. We show that Scnn1a is essential for PHP without adversely affecting baseline neural function or lifespan. However, Scnn1a knockout in a degeneration-causing mutant background accelerated motoneuron loss and disease progression to twice the rate observed in littermate controls with intact PHP. We propose a model of neuroprotective homeostatic plasticity, extending organismal lifespan and health span.
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35
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Pandya VA, Patani R. Decoding the relationship between ageing and amyotrophic lateral sclerosis: a cellular perspective. Brain 2020; 143:1057-1072. [PMID: 31851317 PMCID: PMC7174045 DOI: 10.1093/brain/awz360] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/13/2019] [Accepted: 09/21/2019] [Indexed: 12/13/2022] Open
Abstract
With an ageing population comes an inevitable increase in the prevalence of age-associated neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), a relentlessly progressive and universally fatal disease characterized by the degeneration of upper and lower motor neurons within the brain and spinal cord. Indeed, the physiological process of ageing causes a variety of molecular and cellular phenotypes. With dysfunction at the neuromuscular junction implicated as a key pathological mechanism in ALS, and each lower motor unit cell type vulnerable to its own set of age-related phenotypes, the effects of ageing might in fact prove a prerequisite to ALS, rendering the cells susceptible to disease-specific mechanisms. Moreover, we discuss evidence for overlap between age and ALS-associated hallmarks, potentially implicating cell type-specific ageing as a key contributor to this multifactorial and complex disease. With a dearth of disease-modifying therapy currently available for ALS patients and a substantial failure in bench to bedside translation of other potential therapies, the unification of research in ageing and ALS requires high fidelity models to better recapitulate age-related human disease and will ultimately yield more reliable candidate therapeutics for patients, with the aim of enhancing healthspan and life expectancy.
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Affiliation(s)
- Virenkumar A Pandya
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology, Queen Square, London, UK
- The Francis Crick Institute, London, UK
| | - Rickie Patani
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology, Queen Square, London, UK
- The Francis Crick Institute, London, UK
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36
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Sex-Specific Differences in Motor-Unit Remodeling in a Mouse Model of ALS. eNeuro 2020; 7:ENEURO.0388-19.2020. [PMID: 32033983 PMCID: PMC7044502 DOI: 10.1523/eneuro.0388-19.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/20/2020] [Accepted: 01/27/2020] [Indexed: 12/12/2022] Open
Abstract
Progressive loss of neuromuscular junctions (NMJs) is an early event in amyotrophic lateral sclerosis (ALS), preceding the global degeneration of motor axons and being accompanied by new axonal sprouting within the same axonal arbor. Some aspects of ALS onset and progression seem to be affected by sex in animal models of the disease. However, whether there are sex-specific differences in the pattern or time course of NMJ loss and repair within single motor axons remains unknown. We performed further analysis of a previously published in vivo dataset, obtained from male and female SOD1G37R mice. We found that NMJ losses are as frequent in male and female motor axons but, intriguingly, axonal sprouting is more frequent in female than male mice, resulting in a net increase of axonal arborization. Interestingly, these numerous new axonal branches in female mice are associated with a slightly faster decline in grip strength, increased NMJ denervation, and reduced α-motor neuron survival. Collectively, these results suggest that excessive axonal sprouting and motor-unit (MU) expansion in female SOD1G37R mice are maladaptive during ALS progression.
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Bose P, Tremblay E, Maios C, Narasimhan V, Armstrong GAB, Liao M, Parker JA, Robitaille R, Wen XY, Barden C, Drapeau P. The Novel Small Molecule TRVA242 Stabilizes Neuromuscular Junction Defects in Multiple Animal Models of Amyotrophic Lateral Sclerosis. Neurotherapeutics 2019; 16:1149-1166. [PMID: 31342410 PMCID: PMC6985319 DOI: 10.1007/s13311-019-00765-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder in which the neuromuscular junction progressively degenerates, leading to movement difficulties, paralysis, and eventually death. ALS is currently being treated by only two FDA-approved drugs with modest efficacy in slowing disease progression. Often, the translation of preclinical findings to bedside terminates prematurely as the evaluation of potential therapeutic compounds focuses on a single study or a single animal model. To circumscribe these issues, we screened 3,765 novel small molecule derivatives of pimozide, a recently identified repurposed neuroleptic for ALS, in Caenorhabditis elegans, confirmed the hits in zebrafish and validated the most active compounds in mouse genetic models. Out of the 27 small molecules identified from the high-throughput screen in worms, 4 were found to recover locomotor defects in C. elegans and genetic zebrafish models of ALS. TRVA242 was identified as the most potent compound as it significantly improved efficiency in rescuing locomotor, motorneuron, and neuromuscular junction synaptic deficits in a C. elegans TDP-43 model and in multiple zebrafish genetic (TDP-43, SOD1, and C9ORF72) models of ALS. The actions of TRVA242 were also conserved in a mammalian model as it also stabilized neuromuscular junction deficits in a mouse SOD1 model of ALS. Compounds such as TRVA242 therefore represent new potential therapeutics for the treatment of ALS.
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Affiliation(s)
- Poulomee Bose
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada
- Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM Tour Viger R09-482), 900 Rue Saint Denis, Montréal, Quebec, H2X 0A9, Canada
| | - Elsa Tremblay
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada
- FRQS Group de recherche sur le system nerveux centrale, Montreal, Canada
| | - Claudia Maios
- Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM Tour Viger R09-482), 900 Rue Saint Denis, Montréal, Quebec, H2X 0A9, Canada
| | - Vijay Narasimhan
- Zebrafish Centre for Advanced Drug Discovery and Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital and Department of Medicine and Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Gary A B Armstrong
- Department of Neurology and Neurosurgery, McGill University and Montreal Neurological Institute, Montreal, Canada
| | - Meijiang Liao
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada
- Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM Tour Viger R09-482), 900 Rue Saint Denis, Montréal, Quebec, H2X 0A9, Canada
| | - J Alex Parker
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada
- Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM Tour Viger R09-482), 900 Rue Saint Denis, Montréal, Quebec, H2X 0A9, Canada
| | - Richard Robitaille
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada
- FRQS Group de recherche sur le system nerveux centrale, Montreal, Canada
| | - Xiao Yan Wen
- Zebrafish Centre for Advanced Drug Discovery and Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital and Department of Medicine and Physiology, University of Toronto, Toronto, Ontario, Canada
| | | | - Pierre Drapeau
- Department of Neuroscience, Université de Montréal, Montréal, Quebec, Canada.
- Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM Tour Viger R09-482), 900 Rue Saint Denis, Montréal, Quebec, H2X 0A9, Canada.
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Peng JJ, Lin SH, Liu YT, Lin HC, Li TN, Yao CK. A circuit-dependent ROS feedback loop mediates glutamate excitotoxicity to sculpt the Drosophila motor system. eLife 2019; 8:47372. [PMID: 31318331 PMCID: PMC6682402 DOI: 10.7554/elife.47372] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/17/2019] [Indexed: 12/12/2022] Open
Abstract
Overproduction of reactive oxygen species (ROS) is known to mediate glutamate excitotoxicity in neurological diseases. However, how ROS burdens can influence neural circuit integrity remains unclear. Here, we investigate the impact of excitotoxicity induced by depletion of Drosophila Eaat1, an astrocytic glutamate transporter, on locomotor central pattern generator (CPG) activity, neuromuscular junction architecture, and motor function. We show that glutamate excitotoxicity triggers a circuit-dependent ROS feedback loop to sculpt the motor system. Excitotoxicity initially elevates ROS, thereby inactivating cholinergic interneurons and consequently changing CPG output activity to overexcite motor neurons and muscles. Remarkably, tonic motor neuron stimulation boosts muscular ROS, gradually dampening muscle contractility to feedback-enhance ROS accumulation in the CPG circuit and subsequently exacerbate circuit dysfunction. Ultimately, excess premotor excitation of motor neurons promotes ROS-activated stress signaling that alters neuromuscular junction architecture. Collectively, our results reveal that excitotoxicity-induced ROS can perturb motor system integrity through a circuit-dependent mechanism.
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Affiliation(s)
- Jhan-Jie Peng
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China.,Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei, Taiwan, Republic of China
| | - Shih-Han Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Yu-Tzu Liu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Hsin-Chieh Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Tsai-Ning Li
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China
| | - Chi-Kuang Yao
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, Republic of China.,Institute of Biochemical Sciences, College of Life Science, National Taiwan University, Taipei, Taiwan, Republic of China
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Xiao Y, Zhang J, Shu X, Bai L, Xu W, Wang A, Chen A, Tu WY, Wang J, Zhang K, Luo B, Shen C. Loss of mitochondrial protein CHCHD10 in skeletal muscle causes neuromuscular junction impairment. Hum Mol Genet 2019; 29:1784-1796. [PMID: 31261376 DOI: 10.1093/hmg/ddz154] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/11/2019] [Accepted: 06/21/2019] [Indexed: 12/12/2022] Open
Abstract
Abstract
The neuromuscular junction (NMJ) is a synapse between motoneurons and skeletal muscles to control motor behavior. Acetylcholine receptors (AChRs) are restricted at the synaptic region for proper neurotransmission. Mutations in the mitochondrial CHCHD10 protein have been identified in multiple neuromuscular disorders; however, the physiological roles of CHCHD10 at NMJs remain elusive. Here, we report that CHCHD10 is highly expressed at the postsynapse of NMJs in skeletal muscles. Muscle conditional knockout CHCHD10 mice showed motor defects, abnormal neuromuscular transmission and NMJ structure. Mechanistically, we found that mitochondrial CHCHD10 is required for ATP production, which facilitates AChR expression and promotes agrin-induced AChR clustering. Importantly, ATP could effectively rescue the reduction of AChR clusters in the CHCHD10-ablated muscles. Our study elucidates a novel physiological role of CHCHD10 at the peripheral synapse. It suggests that mitochondria dysfunction contributes to neuromuscular pathogenesis.
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Affiliation(s)
- Yatao Xiao
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
- Department of Neurobiology, Key laboratory of Medical Neurobiology of Zhejiang Province, School of Medicine, Zhejiang University, Zhejiang, China 310058
| | - Jianmin Zhang
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Xiaoqiu Shu
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Lei Bai
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Wentao Xu
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Ailian Wang
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Aizhong Chen
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Wen-Yo Tu
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Jianwen Wang
- The First Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Kejing Zhang
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
- Department of Neurobiology, Key laboratory of Medical Neurobiology of Zhejiang Province, School of Medicine, Zhejiang University, Zhejiang, China 310058
| | - Benyan Luo
- The First Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang, China 310003
| | - Chengyong Shen
- The First Affiliated Hospital, Institute of Translational Medicine, School of Medicine, Zhejiang University, Zhejiang, China 310003
- Department of Neurobiology, Key laboratory of Medical Neurobiology of Zhejiang Province, School of Medicine, Zhejiang University, Zhejiang, China 310058
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40
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Fogarty MJ, Gonzalez Porras MA, Mantilla CB, Sieck GC. Diaphragm neuromuscular transmission failure in aged rats. J Neurophysiol 2019; 122:93-104. [PMID: 31042426 PMCID: PMC6689786 DOI: 10.1152/jn.00061.2019] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/26/2019] [Accepted: 04/26/2019] [Indexed: 12/16/2022] Open
Abstract
In aging Fischer 344 rats, phrenic motor neuron loss, neuromuscular junction abnormalities, and diaphragm muscle (DIAm) sarcopenia are present by 24 mo of age, with larger fast-twitch fatigue-intermediate (type FInt) and fast-twitch fatigable (type FF) motor units particularly vulnerable. We hypothesize that in old rats, DIAm neuromuscular transmission deficits are specific to type FInt and/or FF units. In phrenic nerve/DIAm preparations from rats at 6 and 24 mo of age, the phrenic nerve was supramaximally stimulated at 10, 40, or 75 Hz. Every 15 s, the DIAm was directly stimulated, and the difference in forces evoked by nerve and muscle stimulation was used to estimate neuromuscular transmission failure. Neuromuscular transmission failure in the DIAm was observed at each stimulation frequency. In the initial stimulus trains, the forces evoked by phrenic nerve stimulation at 40 and 75 Hz were significantly less than those evoked by direct muscle stimulation, and this difference was markedly greater in 24-mo-old rats. During repetitive nerve stimulation, neuromuscular transmission failure at 40 and 75 Hz worsened to a greater extent in 24-mo-old rats compared with younger animals. Because type IIx and/or IIb DIAm fibers (type FInt and/or FF motor units) display greater susceptibility to neuromuscular transmission failure at higher frequencies of stimulation, these data suggest that the age-related loss of larger phrenic motor neurons impacts nerve conduction to muscle at higher frequencies and may contribute to DIAm sarcopenia in old rats. NEW & NOTEWORTHY Diaphragm muscle (DIAm) sarcopenia, phrenic motor neuron loss, and perturbations of neuromuscular junctions (NMJs) are well described in aged rodents and selectively affect FInt and FF motor units. Less attention has been paid to the motor unit-specific aspects of nerve-muscle conduction. In old rats, increased neuromuscular transmission failure occurred at stimulation frequencies where FInt and FF motor units exhibit conduction failures, along with decreased apposition of pre- and postsynaptic domains of DIAm NMJs of these units.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
| | | | - Carlos B Mantilla
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic , Rochester, Minnesota
| | - Gary C Sieck
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic , Rochester, Minnesota
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Lee JD, Liu N, Levin SC, Ottosson L, Andersson U, Harris HE, Woodruff TM. Therapeutic blockade of HMGB1 reduces early motor deficits, but not survival in the SOD1 G93A mouse model of amyotrophic lateral sclerosis. J Neuroinflammation 2019; 16:45. [PMID: 30782181 PMCID: PMC6380064 DOI: 10.1186/s12974-019-1435-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/13/2019] [Indexed: 12/13/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a fatal and rapidly progressing neurodegenerative disease without effective treatment. The receptor for advanced glycation end products (RAGE) and the toll-like receptor (TLR) system are major components of the innate immune system, which have been implicated in ALS pathology. Extracellularly released high-mobility group box 1 (HMGB1) is a pleiotropic danger-associated molecular pattern (DAMP), and is an endogenous ligand for both RAGE and TLR4. Methods The present study examined the effect of HMGB1 inhibition on disease progression in the preclinical SOD1G93A transgenic mouse model of ALS using a potent anti-HMGB1 antibody (2G7), which targets the extracellular DAMP form of HMGB1. Results We found that chronic intraperitoneal dosing of the anti-HMGB1 antibody to SOD1G93A mice transiently improved hind-limb grip strength early in the disease, but did not extend survival. Anti-HMGB1 treatment also reduced tumour necrosis factor α and complement C5a receptor 1 gene expression in the spinal cord, but did not affect overall glial activation. Conclusions In summary, our results indicate that therapeutic targeting of an extracellular DAMP, HMGB1, improves early motor dysfunction, but overall has limited efficacy in the SOD1G93A mouse model of ALS.
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Affiliation(s)
- John D Lee
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.,Faculty of Medicine, University of Queensland Centre for Clinical Research, The University of Queensland, Herston, Brisbane, QLD, 4029, Australia
| | - Ning Liu
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
| | - Samantha C Levin
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
| | - Lars Ottosson
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Ulf Andersson
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Helena E Harris
- Centre for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Trent M Woodruff
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.
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42
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Borroni B, Alberici A, Buratti E. Review: Molecular pathology of frontotemporal lobar degenerations. Neuropathol Appl Neurobiol 2019; 45:41-57. [DOI: 10.1111/nan.12534] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 12/04/2018] [Indexed: 02/07/2023]
Affiliation(s)
- B. Borroni
- Neurology Clinic; Department of Clinical and Experimental Sciences; University of Brescia; Brescia Italy
| | - A. Alberici
- Neurology Clinic; Department of Clinical and Experimental Sciences; University of Brescia; Brescia Italy
| | - E. Buratti
- International Centre for Genetic Engineering and Biotechnology (ICGEB); Trieste Italy
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Abstract
The synapse is an incredibly specialized structure that allows for the coordinated communication of information from one neuron to another. When assembled into circuits, steady streams of excitatory and inhibitory synaptic activity shape neural outputs. At the organismal level, ensembles of neural networks underlie behavior, emotion and memory. Disorder or dysfunctions of synapses, a synaptopathy, may underlie a host of developmental and degenerative neurological conditions. There is a possibility that amyotrophic lateral sclerosis may be a result of a synaptopathy within the neuromotor system. To this end, particular attention has been trained on the excitatory glutamatergic synapses and their morphological proxy, the dendritic spine. The extensive detailing of these dysfunctions in vulnerable neuronal populations, including corticospinal neurons and motor neurons, has recently been the subject of original research in rodents and humans. If amyotrophic lateral sclerosis is indeed a synaptopathy, it is entirely consistent with other proposed pathogenic mechanisms – including glutamate excitotoxicity, accumulation of misfolded proteins and mitochondrial dysfunction at distal axon terminals (cortico-motor neuron and neuromuscular). Further, although the exact mechanism of disease spread from region to region is unknown, the synaptopathy hypothesis is consistent with emerging die-forward evidence and the prion-like propagation of misfolded protein aggregates to distant neuronal populations. Here in this mini-review, we focus on the timeline of synaptic observations in both cortical and spinal neurons from different rodent models, and provide a conceptual framework for assessing the synaptopathy hypothesis in amyotrophic lateral sclerosis.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA; School of Biomedical Sciences, The University of Queensland, St. Lucia, Australia
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44
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Bose P, Armstrong GAB, Drapeau P. Neuromuscular junction abnormalities in a zebrafish loss-of-function model of TDP-43. J Neurophysiol 2018; 121:285-297. [PMID: 30461368 DOI: 10.1152/jn.00265.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Almost 90% of amyotrophic lateral sclerosis (ALS) cases are characterized by the presence of aggregates of insoluble, misfolded cytoplasmic TAR DNA binding protein of 43 kDa (TDP-43). Distal axonopathy with impaired neuromuscular junctions (NMJs) before motor neuron degeneration or clinical onset of symptoms has been hypothesized as an early pathology in ALS. However, synaptic defects at the NMJ caused by TDP-43 mutations have not been characterized. In this study, we examined a previously reported zebrafish line expressing the tardbpY220X/Y220X variant, which results in an unstable and degraded protein. These tardbp-/- larvae, however, mature normally due to the upregulated expression of an alternative splice variant of the tardbp paralog tardbp-like, or tardbpl. We generated a mutant line with a CRISPR/Cas9-mediated 5-base pair deletion encompassing the ATG start codon of tardbpl and in-crossed these with tardbp-/- mutants to obtain tardbp-/- and tardbpl-/- double mutants, herein referred to as hom/hom. We subsequently characterized morphological, coiling, locomotor, synaptic, and NMJ structural abnormalities in the hom/hom mutants and in their genotypic controls. We observed that hom/hom mutants displayed gross morphological defects, early lethality, reduced locomotor function, aberrant quantal transmission, and perturbed synapse architecture at the NMJ. We further employed pharmacological manipulations in an effort to rescue phenotypic defects and observed that tardbp+/-; tardbpl-/- (herein referred to as het/hom) mutants, but not hom/hom mutants, were sensitive to chronic treatments of BAY K 8644, an L-type calcium channel agonist. This result highlights the importance of partial vs. complete loss of allelic functions of TDP-43. NEW & NOTEWORTHY This study highlights the importance of partial vs. complete loss of allelic functions of TDP-43 in a zebrafish loss of function model, thus making it an attractive tool for drug screening approaches.
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Affiliation(s)
- Poulomee Bose
- Department of Neuroscience, Centre de Recherche du Centre Hospitalier de l'Université de Montréal , Montreal, Quebec , Canada
| | - Gary A B Armstrong
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University , Montreal, Quebec , Canada
| | - Pierre Drapeau
- Department of Neuroscience, Centre de Recherche du Centre Hospitalier de l'Université de Montréal , Montreal, Quebec , Canada
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45
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Lee JD, Levin SC, Willis EF, Li R, Woodruff TM, Noakes PG. Complement components are upregulated and correlate with disease progression in the TDP-43 Q331K mouse model of amyotrophic lateral sclerosis. J Neuroinflammation 2018; 15:171. [PMID: 29859100 PMCID: PMC5984816 DOI: 10.1186/s12974-018-1217-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 05/24/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Components of the innate immune complement system have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS) specifically using hSOD1 transgenic animals; however, a comprehensive examination of complement expression in other transgenic ALS models has not been performed. This study therefore aimed to determine the expression of several key complement components and regulators in the lumbar spinal cord and tibialis anterior muscle of TDP-43Q331K mice during different disease ages. METHODS Non-transgenic, TDP-43WT and TDP-43Q331K mice were examined at three different ages of disease progression. Expression of complement components and their regulators were examined using real-time quantitative PCR and enzyme-linked immunosorbent assay. Localisation of terminal complement component receptor C5aR1 within the lumbar spinal cord was also investigated using immunohistochemistry. RESULTS Altered levels of several major complement factors, including C5a, in the spinal cord and tibialis anterior muscle of TDP-43Q331K mice were observed as disease progressed, suggesting overall increased complement activation in TDP-43Q331K mice. C5aR1 increased during disease progression, with immuno-localisation demonstrating expression on motor neurons and expression on microglia surrounding the regions of motor neuron death. There was a strong negative linear relationship between spinal cord C1qB, C3 and C5aR1 mRNA levels with hind-limb grip strength. CONCLUSIONS These results indicate that similar to SOD1 transgenic animals, local complement activation and increased expression of C5aR1 may contribute to motor neuron death and neuromuscular junction denervation in the TDP-43Q331K mouse ALS model. This further validates C5aR1 as a potential therapeutic target for ALS.
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Affiliation(s)
- John D. Lee
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
- University of Queensland Centre for Clinical Research, the University of Queensland, Herston, Brisbane, QLD 4029 Australia
| | - Samantha C. Levin
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
| | - Emily F. Willis
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
| | - Rui Li
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
| | - Trent M. Woodruff
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
| | - Peter G. Noakes
- School of Biomedical Sciences, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
- Queensland Brain Institute, the University of Queensland, St Lucia, Brisbane, QLD 4072 Australia
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46
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Shenouda M, Zhang AB, Weichert A, Robertson J. Mechanisms Associated with TDP-43 Neurotoxicity in ALS/FTLD. ADVANCES IN NEUROBIOLOGY 2018; 20:239-263. [PMID: 29916022 DOI: 10.1007/978-3-319-89689-2_9] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The discovery of TDP-43 as a major disease protein in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) was first made in 2006. Prior to 2006 there were only 11 publications related to TDP-43, now there are over 2000, indicating the importance of TDP-43 to unraveling the complex molecular mechanisms that underpin the pathogenesis of ALS/FTLD. Subsequent to this discovery, TDP-43 pathology was also found in other neurodegenerative diseases, including Alzheimer's disease, the significance of which is still in the early stages of exploration. TDP-43 is a predominantly nuclear DNA/RNA-binding protein, one of a number of RNA-binding proteins that are now known to be linked with ALS/FTLD, including Fused in Sarcoma (FUS), heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), and heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1). However, what sets TDP-43 apart is the vast number of cases in which TDP-43 pathology is present, providing a point of convergence, the understanding of which could lead to broadly applicable therapeutics. Here we will focus on TDP-43 in ALS/FTLD, its nuclear and cytoplasmic functions, and consequences should these functions go awry.
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Affiliation(s)
- Marc Shenouda
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Ashley B Zhang
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Anna Weichert
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada
| | - Janice Robertson
- Tanz Centre for Research in Neurodegenerative Diseases and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5T 2S8, Canada.
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