1
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Canny E, Vansteensel MJ, van der Salm SMA, Müller-Putz GR, Berezutskaya J. Boosting brain-computer interfaces with functional electrical stimulation: potential applications in people with locked-in syndrome. J Neuroeng Rehabil 2023; 20:157. [PMID: 37980536 PMCID: PMC10656959 DOI: 10.1186/s12984-023-01272-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/23/2023] [Indexed: 11/20/2023] Open
Abstract
Individuals with a locked-in state live with severe whole-body paralysis that limits their ability to communicate with family and loved ones. Recent advances in brain-computer interface (BCI) technology have presented a potential alternative for these people to communicate by detecting neural activity associated with attempted hand or speech movements and translating the decoded intended movements to a control signal for a computer. A technique that could potentially enrich the communication capacity of BCIs is functional electrical stimulation (FES) of paralyzed limbs and face to restore body and facial movements of paralyzed individuals, allowing to add body language and facial expression to communication BCI utterances. Here, we review the current state of the art of existing BCI and FES work in people with paralysis of body and face and propose that a combined BCI-FES approach, which has already proved successful in several applications in stroke and spinal cord injury, can provide a novel promising mode of communication for locked-in individuals.
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Affiliation(s)
- Evan Canny
- Department of Neurology and Neurosurgery, Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mariska J Vansteensel
- Department of Neurology and Neurosurgery, Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Sandra M A van der Salm
- Department of Neurology and Neurosurgery, Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Gernot R Müller-Putz
- Institute of Neural Engineering, Laboratory of Brain-Computer Interfaces, Graz University of Technology, Graz, Austria
| | - Julia Berezutskaya
- Department of Neurology and Neurosurgery, Brain Center, University Medical Center Utrecht, Utrecht, The Netherlands.
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2
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Massih B, Veh A, Schenke M, Mungwa S, Seeger B, Selvaraj BT, Chandran S, Reinhardt P, Sterneckert J, Hermann A, Sendtner M, Lüningschrör P. A 3D cell culture system for bioengineering human neuromuscular junctions to model ALS. Front Cell Dev Biol 2023; 11:996952. [PMID: 36866276 PMCID: PMC9973451 DOI: 10.3389/fcell.2023.996952] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 01/16/2023] [Indexed: 02/16/2023] Open
Abstract
The signals that coordinate and control movement in vertebrates are transmitted from motoneurons (MNs) to their target muscle cells at neuromuscular junctions (NMJs). Human NMJs display unique structural and physiological features, which make them vulnerable to pathological processes. NMJs are an early target in the pathology of motoneuron diseases (MND). Synaptic dysfunction and synapse elimination precede MN loss suggesting that the NMJ is the starting point of the pathophysiological cascade leading to MN death. Therefore, the study of human MNs in health and disease requires cell culture systems that enable the connection to their target muscle cells for NMJ formation. Here, we present a human neuromuscular co-culture system consisting of induced pluripotent stem cell (iPSC)-derived MNs and 3D skeletal muscle tissue derived from myoblasts. We used self-microfabricated silicone dishes combined with Velcro hooks to support the formation of 3D muscle tissue in a defined extracellular matrix, which enhances NMJ function and maturity. Using a combination of immunohistochemistry, calcium imaging, and pharmacological stimulations, we characterized and confirmed the function of the 3D muscle tissue and the 3D neuromuscular co-cultures. Finally, we applied this system as an in vitro model to study the pathophysiology of Amyotrophic Lateral Sclerosis (ALS) and found a decrease in neuromuscular coupling and muscle contraction in co-cultures with MNs harboring ALS-linked SOD1 mutation. In summary, the human 3D neuromuscular cell culture system presented here recapitulates aspects of human physiology in a controlled in vitro setting and is suitable for modeling of MND.
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Affiliation(s)
- Bita Massih
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Alexander Veh
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Maren Schenke
- Institute for Food Quality and Safety, Research Group Food Toxicology and Alternative/Complementary Methods to Animal Experiments, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Simon Mungwa
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Bettina Seeger
- Institute for Food Quality and Safety, Research Group Food Toxicology and Alternative/Complementary Methods to Animal Experiments, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Bhuvaneish T. Selvaraj
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- UK Dementia Research Institute at University of Edinburgh, University of Edinburgh, Edinburgh, United Kingdom
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
| | - Siddharthan Chandran
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
- UK Dementia Research Institute at University of Edinburgh, University of Edinburgh, Edinburgh, United Kingdom
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter Reinhardt
- Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany
| | - Jared Sterneckert
- Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany
- Medical Faculty Carl Gustav Carus of TU Dresden, Dresden, Germany
| | - Andreas Hermann
- Translational Neurodegeneration Section “Albrecht-Kossel”, Department of Neurology, University Medical Center Rostock, Rostock, Germany
- Center for Transdisciplinary Neurosciences Rostock, University Medical Center Rostock, Rostock, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) Rostock/Greifswald, Rostock, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Patrick Lüningschrör
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
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3
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A link between agrin signalling and Ca v3.2 at the neuromuscular junction in spinal muscular atrophy. Sci Rep 2022; 12:18960. [PMID: 36347955 PMCID: PMC9643518 DOI: 10.1038/s41598-022-23703-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 11/03/2022] [Indexed: 11/11/2022] Open
Abstract
SMN protein deficiency causes motoneuron disease spinal muscular atrophy (SMA). SMN-based therapies improve patient motor symptoms to variable degrees. An early hallmark of SMA is the perturbation of the neuromuscular junction (NMJ), a synapse between a motoneuron and muscle cell. NMJ formation depends on acetylcholine receptor (AChR) clustering triggered by agrin and its co-receptors lipoprotein receptor-related protein 4 (LRP4) and transmembrane muscle-specific kinase (MuSK) signalling pathway. We have previously shown that flunarizine improves NMJs in SMA model mice, but the mechanisms remain elusive. We show here that flunarizine promotes AChR clustering in cell-autonomous, dose- and agrin-dependent manners in C2C12 myotubes. This is associated with an increase in protein levels of LRP4, integrin-beta-1 and alpha-dystroglycan, three agrin co-receptors. Furthermore, flunarizine enhances MuSK interaction with integrin-beta-1 and phosphotyrosines. Moreover, the drug acts on the expression and splicing of Agrn and Cacna1h genes in a muscle-specific manner. We reveal that the Cacna1h encoded protein Cav3.2 closely associates in vitro with the agrin co-receptor LRP4. In vivo, it is enriched nearby NMJs during neonatal development and the drug increases this immunolabelling in SMA muscles. Thus, flunarizine modulates key players of the NMJ and identifies Cav3.2 as a new protein involved in the NMJ biology.
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4
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Roy A, Kumar A. Supraphysiological activation of TAK1 promotes skeletal muscle growth and mitigates neurogenic atrophy. Nat Commun 2022; 13:2201. [PMID: 35459245 PMCID: PMC9033787 DOI: 10.1038/s41467-022-29752-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 03/30/2022] [Indexed: 12/25/2022] Open
Abstract
Skeletal muscle mass is regulated through coordinated activation of multiple signaling pathways. TAK1 signalosome has been found to be activated in various conditions of muscle atrophy and hypertrophy. However, the role and mechanisms by which TAK1 regulates skeletal muscle mass remain less understood. Here, we demonstrate that supraphysiological activation of TAK1 in skeletal muscle of adult mice stimulates translational machinery, protein synthesis, and myofiber growth. TAK1 causes phosphorylation of elongation initiation factor 4E (eIF4E) independent of mTOR. Inactivation of TAK1 disrupts neuromuscular junction morphology and causes deregulation of Smad signaling. Using genetic approaches, we demonstrate that TAK1 prevents excessive loss of muscle mass during denervation. TAK1 favors the nuclear translocation of Smad4 and cytoplasmic retention of Smad6. TAK1 is also required for the phosphorylation of eIF4E in denervated skeletal muscle. Collectively, our results demonstrate that TAK1 supports skeletal muscle growth and prevents neurogenic muscle atrophy in adult mice. TGF-β-activated kinase 1 (TAK1) is essential for the maintenance of skeletal muscle mass through incompletely understood mechanisms. Here the authors show that supraphysiological activation of TAK1 leads to muscle hypertrophy through the elongation initiation factor 4E (eIF4E) involved in protein synthesis, and prevents denervation-induced atrophy in mice.
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Affiliation(s)
- Anirban Roy
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX, USA
| | - Ashok Kumar
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Houston, TX, USA.
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5
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Butti Z, Pan YE, Giacomotto J, Patten SA. Reduced C9orf72 function leads to defective synaptic vesicle release and neuromuscular dysfunction in zebrafish. Commun Biol 2021; 4:792. [PMID: 34172817 PMCID: PMC8233344 DOI: 10.1038/s42003-021-02302-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 06/03/2021] [Indexed: 11/16/2022] Open
Abstract
The most common genetic cause of amyotrophic lateral sclerosis (ALS) and fronto-temporal dementia (FTD) is a hexanucleotide repeat expansion within the C9orf72 gene. Reduced levels of C9orf72 mRNA and protein have been found in ALS/FTD patients, but the role of this protein in disease pathogenesis is still poorly understood. Here, we report the generation and characterization of a stable C9orf72 loss-of-function (LOF) model in the zebrafish. We show that reduced C9orf72 function leads to motor defects, muscle atrophy, motor neuron loss and mortality in early larval and adult stages. Analysis of the structure and function of the neuromuscular junctions (NMJs) of the larvae, reveal a marked reduction in the number of presynaptic and postsynaptic structures and an impaired release of quantal synaptic vesicles at the NMJ. Strikingly, we demonstrate a downregulation of SV2a upon C9orf72-LOF and a reduced rate of synaptic vesicle cycling. Furthermore, we show a reduced number and size of Rab3a-postive synaptic puncta at NMJs. Altogether, these results reveal a key function for C9orf72 in the control of presynaptic vesicle trafficking and release at the zebrafish larval NMJ. Our study demonstrates an important role for C9orf72 in ALS/FTD pathogenesis, where it regulates synaptic vesicle release and neuromuscular functions. Butti et al. generate a C9orf72 loss-of-function model in zebrafish. They find that that C9orf72 is required for presynaptic vesicle trafficking and release at the zebrafish larval neuromuscular junctions. This study provides functional insights into the pathogenesis of amyotrophic lateral sclerosis and fronto-temporal dementia.
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Affiliation(s)
- Zoé Butti
- INRS- Centre Armand-Frappier Santé Biotechnologie, Laval, QC, Canada
| | | | - Jean Giacomotto
- Queensland Brain Institute, University of Queensland, St Lucia, QLD, Australia.,Queensland Centre for Mental Health Research, Brisbane, QLD, Australia
| | - Shunmoogum A Patten
- INRS- Centre Armand-Frappier Santé Biotechnologie, Laval, QC, Canada. .,Centre d'Excellence en Recherche sur les Maladies Orphelines - Fondation Courtois (CERMO-FC), Université du Québec à Montréal (UQAM), Montréal, QC, Canada.
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6
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Tay SH, Winanto, Khong ZJ, Koh YH, Ng SY. Generation of Cortical, Dopaminergic, Motor, and Sensory Neurons from Human Pluripotent Stem Cells. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2549:359-377. [PMID: 33959917 DOI: 10.1007/7651_2021_399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The use of patient-derived induced pluripotent stem cells (iPSCs) and their neural derivatives is becoming increasingly important in the study of neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Lewy body dementia, amyotrophic lateral sclerosis, peripheral neuropathy, and so on. Increasingly, iPSC-derived neurons also reveal key pathways and signaling defects in psychiatric disorders such as autism spectrum disorders, schizophrenia, and bipolar disorder. With recent advances in CRISPR/Cas9-mediated genome editing technology, patient-derived iPSCs with disease-causing mutations can be corrected into "isogenic control lines," and these can be differentiated into neural derivatives with identical genetic background. This provides an opportunity for in vitro disease modeling to unravel disease mechanisms and a platform to facilitate drug discovery. In this chapter, we provide details of the differentiation protocols to reliably derive four currently relevant neuronal subtypes, i.e., cortical neurons, midbrain dopaminergic neurons, spinal motor neurons, and sensory neurons.
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Affiliation(s)
- Shermaine Huiping Tay
- Institute of Molecular and Cell Biology, A*STAR Research Entities, Singapore, Singapore
| | - Winanto
- Institute of Molecular and Cell Biology, A*STAR Research Entities, Singapore, Singapore
| | - Zi Jian Khong
- Institute of Molecular and Cell Biology, A*STAR Research Entities, Singapore, Singapore.,NUS Graduate School for Integrative Science and Engineering, National University of Singapore, Singapore, Singapore
| | - Yong Hui Koh
- Institute of Molecular and Cell Biology, A*STAR Research Entities, Singapore, Singapore.,Yong Loo Lin School of Medicine (Physiology), National University of Singapore, Singapore, Singapore
| | - Shi Yan Ng
- Institute of Molecular and Cell Biology, A*STAR Research Entities, Singapore, Singapore. .,Yong Loo Lin School of Medicine (Physiology), National University of Singapore, Singapore, Singapore. .,National Neuroscience Institute, Singapore, Singapore.
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7
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Stoklund Dittlau K, Krasnow EN, Fumagalli L, Vandoorne T, Baatsen P, Kerstens A, Giacomazzi G, Pavie B, Rossaert E, Beckers J, Sampaolesi M, Van Damme P, Van Den Bosch L. Human motor units in microfluidic devices are impaired by FUS mutations and improved by HDAC6 inhibition. Stem Cell Reports 2021; 16:2213-2227. [PMID: 33891869 PMCID: PMC8452598 DOI: 10.1016/j.stemcr.2021.03.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/13/2022] Open
Abstract
Neuromuscular junctions (NMJs) ensure communication between motor neurons (MNs) and muscle; however, in MN disorders, such as amyotrophic lateral sclerosis (ALS), NMJs degenerate resulting in muscle atrophy. The aim of this study was to establish a versatile and reproducible in vitro model of a human motor unit to investigate the effects of ALS-causing mutations. Therefore, we generated a co-culture of human induced pluripotent stem cell (iPSC)-derived MNs and human primary mesoangioblast-derived myotubes in microfluidic devices. A chemotactic and volumetric gradient facilitated the growth of MN neurites through microgrooves resulting in the interaction with myotubes and the formation of NMJs. We observed that ALS-causing FUS mutations resulted in reduced neurite outgrowth as well as an impaired neurite regrowth upon axotomy. NMJ numbers were likewise reduced in the FUS-ALS model. Interestingly, the selective HDAC6 inhibitor, Tubastatin A, improved the neurite outgrowth, regrowth, and NMJ morphology, prompting HDAC6 inhibition as a potential therapeutic strategy for ALS. Human motor units with functional NMJs can be generated using microfluidic devices FUS-ALS motor units display impaired neurite regrowth, outgrowth and NMJ numbers HDAC6 inhibition alleviate FUS-ALS motor unit pathology in vitro
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Affiliation(s)
- Katarina Stoklund Dittlau
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Emily N Krasnow
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Laura Fumagalli
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Tijs Vandoorne
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Pieter Baatsen
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Axelle Kerstens
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Giorgia Giacomazzi
- KU Leuven - University of Leuven, Department of Development and Regeneration, Stem Cell and Developmental Biology, Leuven, Belgium
| | - Benjamin Pavie
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Elisabeth Rossaert
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Jimmy Beckers
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Maurilio Sampaolesi
- KU Leuven - University of Leuven, Department of Development and Regeneration, Stem Cell and Developmental Biology, Leuven, Belgium
| | - Philip Van Damme
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium; University Hospitals Leuven, Department of Neurology, Leuven, Belgium
| | - Ludo Van Den Bosch
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
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8
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Servais L, Baranello G, Scoto M, Daron A, Oskoui M. Therapeutic interventions for spinal muscular atrophy: preclinical and early clinical development opportunities. Expert Opin Investig Drugs 2021; 30:519-527. [PMID: 33749510 DOI: 10.1080/13543784.2021.1904889] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative neuromuscular disease that presents primarily in children. Abnormalities in the SMN1 gene cause reduced levels of the survival motor neuron (SMN) protein, while a second gene, SMN2, produces low levels of functional SMN protein. Currently available drugs do not cure, so a significant unmet need remains for patients treated after symptom onset. AREAS COVERED Drugs available in the clinic, investigational agents and key questions for researchers are discussed. A pragmatic search of the literature was performed to identify therapies in late stages of preclinical, or in early stages of clinical development. This list was compared to the CureSMA pipeline for completeness. Drugs approved for indications that have potential for impact for SMA were included. These drugs target the primary deficiency in SMN protein or other pathways involved in SMA pathophysiology that are not SMN-protein dependent. EXPERT OPINION Children treated after the onset of symptoms continue to have significant disability. Given the heterogeneity of the population phenotype evidenced by variable response to initial therapy, age at treatment onset and the need to demonstrate added value beyond approved therapeutics, the clinical development of new drugs will be challenging.
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Affiliation(s)
- Laurent Servais
- MDUK Neuromuscular Center, Department of Paediatrics, University of Oxford, Oxford, UK.,Neuromuscular Reference Center Disease, Department of Paediatrics, Liege, Belgium and University of Liege, Liège, Belgium
| | - Giovanni Baranello
- Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Mariacristina Scoto
- Dubowitz Neuromuscular Centre, NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Aurore Daron
- Neuromuscular Reference Center Disease, Department of Paediatrics, Liege, Belgium and University of Liege, Liège, Belgium
| | - Maryam Oskoui
- Departments of Pediatrics and Neurology & Neurosurgery, McGill University, Montreal, QC, Canada
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9
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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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10
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Rios R, Jablonka-Shariff A, Broberg C, Snyder-Warwick AK. Macrophage roles in peripheral nervous system injury and pathology: Allies in neuromuscular junction recovery. Mol Cell Neurosci 2021; 111:103590. [PMID: 33422671 DOI: 10.1016/j.mcn.2021.103590] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 12/15/2020] [Accepted: 01/01/2021] [Indexed: 12/11/2022] Open
Abstract
Peripheral nerve injuries remain challenging to treat despite extensive research on reparative processes at the injury site. Recent studies have emphasized the importance of immune cells, particularly macrophages, in recovery from nerve injury. Macrophage plasticity enables numerous functions at the injury site. At early time points, macrophages perform inflammatory functions, but at later time points, they adopt pro-regenerative phenotypes to support nerve regeneration. Research has largely been limited, however, to the injury site. The neuromuscular junction (NMJ), the synapse between the nerve terminal and end target muscle, has received comparatively less attention, despite the importance of NMJ reinnervation for motor recovery. Macrophages are present at the NMJ following nerve injury. Moreover, in denervating diseases, such as amyotrophic lateral sclerosis (ALS), macrophages may also play beneficial roles at the NMJ. Evidence of positive macrophages roles at the injury site after peripheral nerve injury and at the NMJ in denervating pathologies suggest that macrophages may promote NMJ reinnervation. In this review, we discuss the intersection of nerve injury and immunity, with a focus on macrophages.
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Affiliation(s)
- Rachel Rios
- Washington University School of Medicine, St. Louis, MO, United States of America
| | - Albina Jablonka-Shariff
- Division of Plastic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Curtis Broberg
- Washington University School of Medicine, St. Louis, MO, United States of America
| | - Alison K Snyder-Warwick
- Division of Plastic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, United States of America.
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11
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Kim BW, Ryu J, Jeong YE, Kim J, Martin LJ. Human Motor Neurons With SOD1-G93A Mutation Generated From CRISPR/Cas9 Gene-Edited iPSCs Develop Pathological Features of Amyotrophic Lateral Sclerosis. Front Cell Neurosci 2020; 14:604171. [PMID: 33328898 PMCID: PMC7710664 DOI: 10.3389/fncel.2020.604171] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 10/30/2020] [Indexed: 12/14/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by gradual degeneration and elimination of motor neurons (MNs) in the motor cortex, brainstem, and spinal cord. Some familial forms of ALS are caused by genetic mutations in superoxide dismutase 1 (SOD1) but the mechanisms driving MN disease are unclear. Identifying the naturally occurring pathology and understanding how this mutant SOD1 can affect MNs in translationally meaningful ways in a valid and reliable human cell model remains to be established. Here, using CRISPR/Cas9 genome editing system and human induced pluripotent stem cells (iPSCs), we generated highly pure, iPSC-derived MNs with a SOD1-G93A missense mutation. With the wild-type cell line serving as an isogenic control and MNs from a patient-derived iPSC line with an SOD1-A4V mutation as a comparator, we identified pathological phenotypes relevant to ALS. The mutant MNs accumulated misfolded and aggregated forms of SOD1 in cell bodies and processes, including axons. They also developed distinctive axonal pathologies. Mutants had axonal swellings with shorter axon length and less numbers of branch points. Moreover, structural and molecular abnormalities in presynaptic and postsynaptic size and density were found in the mutants. Finally, functional studies with microelectrode array demonstrated that the individual mutant MNs exhibited decreased number of spikes and diminished network bursting, but increased burst duration. Taken together, we identified spontaneous disease phenotypes relevant to ALS in mutant SOD1 MNs from genome-edited and patient-derived iPSCs. Our findings demonstrate that SOD1 mutations in human MNs cause cell-autonomous proteinopathy, axonopathy, synaptic pathology, and aberrant neurotransmission.
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Affiliation(s)
- Byung Woo Kim
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jiwon Ryu
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Ye Eun Jeong
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Juhyun Kim
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Lee J Martin
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,The Solomon H Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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12
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Boehm I, Miller J, Wishart TM, Wigmore SJ, Skipworth RJ, Jones RA, Gillingwater TH. Neuromuscular junctions are stable in patients with cancer cachexia. J Clin Invest 2020; 130:1461-1465. [PMID: 31794435 PMCID: PMC7269586 DOI: 10.1172/jci128411] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 11/26/2019] [Indexed: 12/19/2022] Open
Abstract
Cancer cachexia is a major cause of patient morbidity and mortality, with no efficacious treatment or management strategy. Despite cachexia sharing pathophysiological features with a number of neuromuscular wasting conditions, including age-related sarcopenia, the mechanisms underlying cachexia remain poorly understood. Studies of related conditions suggest that pathological targeting of the neuromuscular junction (NMJ) may play a key role in cachexia, but this has yet to be investigated in human patients. Here, high-resolution morphological analyses were undertaken on NMJs of rectus abdominis obtained from patients undergoing upper GI cancer surgery compared with controls (N = 30; n = 1,165 NMJs). Cancer patients included those with cachexia and weight-stable disease. Despite the low skeletal muscle index and significant muscle fiber atrophy (P < 0.0001) in patients with cachexia, NMJ morphology was fully conserved. No significant differences were observed in any of the pre- and postsynaptic variables measured. We conclude that NMJs remain structurally intact in rectus abdominis in both cancer and cachexia, suggesting that denervation of skeletal muscle is not a major driver of pathogenesis. The absence of NMJ pathology is in stark contrast to what is found in related conditions, such as age-related sarcopenia, and supports the hypothesis that intrinsic changes within skeletal muscle, independent of any changes in motor neurons, represent the primary locus of neuromuscular pathology in cancer cachexia.
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Affiliation(s)
- Ines Boehm
- Biomedical Sciences, Edinburgh Medical School, Edinburgh, United Kingdom
| | - Janice Miller
- Clinical Surgery, Edinburgh Medical School and Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Thomas M Wishart
- Roslin Institute, University of Edinburgh, Easter Bush Campus, Midlothian, United Kingdom
| | - Stephen J Wigmore
- Clinical Surgery, Edinburgh Medical School and Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Richard Je Skipworth
- Clinical Surgery, Edinburgh Medical School and Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Ross A Jones
- Biomedical Sciences, Edinburgh Medical School, Edinburgh, United Kingdom
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13
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Guo X, Smith V, Jackson M, Tran M, Thomas M, Patel A, Lorusso E, Nimbalkar S, Cai Y, McAleer CW, Wang Y, Long CJ, Hickman JJ. A Human-Based Functional NMJ System for Personalized ALS Modeling and Drug Testing. ADVANCED THERAPEUTICS 2020; 3:2000133. [PMID: 33709015 PMCID: PMC7942691 DOI: 10.1002/adtp.202000133] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Indexed: 01/26/2023]
Abstract
Loss of the neuromuscular junction (NMJ) is an early and critical hallmark in all forms of ALS. The study design was to develop a functional NMJ disease model by integrating motoneurons (MNs) differentiated from multiple ALS-patients' induced pluripotent stem cells (iPSCs) and primary human muscle into a chambered system. NMJ functionality was tested by recording myotube contractions while stimulating MNs by field electrodes and a set of clinically relevant parameters were defined to characterize the NMJ function. Three ALS lines were analyzed, 2 with SOD1 mutations and 1 with a FUS mutation. The ALS-MNs reproduced pathological phenotypes, including increased axonal varicosities, reduced axonal branching and elongation and increased excitability. These MNs formed functional NMJs with wild type muscle, but with significant deficits in NMJ quantity, fidelity and fatigue index. Furthermore, treatment with the Deana protocol was found to correct the NMJ deficits in all the ALS mutant lines tested. Quantitative analysis also revealed the variations inherent in each mutant lines. This functional NMJ system provides a platform for the study of both fALS and sALS and has the capability of being adapted into subtype-specific or patient-specific models for ALS etiological investigation and patient stratification for drug testing.
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Affiliation(s)
- Xiufang Guo
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Virginia Smith
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Max Jackson
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - My Tran
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Michael Thomas
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Aakash Patel
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Eric Lorusso
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Siddharth Nimbalkar
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Yunqing Cai
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Christopher W. McAleer
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Ying Wang
- Department of Biomedical Engineering, 305 Weill Hall, Cornell University, Ithaca, NY, 14853, USA
| | - Christopher J. Long
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - James J. Hickman
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
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14
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Harrison JM, Rafuse VF. Muscle fiber-type specific terminal Schwann cell pathology leads to sprouting deficits following partial denervation in SOD1 G93A mice. Neurobiol Dis 2020; 145:105052. [PMID: 32827689 DOI: 10.1016/j.nbd.2020.105052] [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: 04/24/2020] [Revised: 07/20/2020] [Accepted: 08/13/2020] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an adult-onset disease characterized by the progressive death of motoneurons and denervation of muscle fibers. To restore motor function, surviving motoneurons in partially denervated muscles typically sprout axons to reinnervate denervated endplates. However, studies on the SOD1G93A rodent models of ALS indicate that sprouting is significantly limited in fast, but not slow, twitch muscles after disease onset. This limitation hastens the rate of muscle weakness and loss of motor function. The causes of this limitation are currently unknown. Sprouting could be limited because the SOD1G93A mutation weakens motoneurons making them incapable of expanding their field of innervation. Alternatively, motoneurons may be capable of sprouting, but unable to do so due to the loss of a permissive sprouting environment. To distinguish between the two possibilities, we compared the sprouting capacity of motoneuron subtypes by partially denervating the fast twitch plantaris (composed of type IIa/IIb muscle fibers) and slow twitch soleus muscles (type I/IIa fibers) prior to disease onset and weakening in SOD1G93A and WT mice. We found that only motoneurons innervating the SOD1G93A plantaris had a limited sprouting capacity. This was correlated with the selective loss of terminal Schwann cells (TSCs) at IIb fibers and an increase in macrophage infiltration. Treating SOD1G93A mice with the tyrosine kinase inhibitor, masitinib, significantly reduced infiltration, prevented TSC loss, and increased the sprouting capacity to near normal. These results suggest that TSCs at denervated type IIb muscle fibers are aberrantly targeted by infiltrating macrophages in SOD1G93A mice, and their loss accounts, at least in part, for the compromised sprouting capacity of the largest motoneurons during early stages of ALS.
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Affiliation(s)
- Julia M Harrison
- Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia B3H 1X5, Canada; Brain Repair Centre, Life Sciences Research Institute, Halifax, Nova Scotia B3H 4R2, Canada
| | - Victor F Rafuse
- Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia B3H 1X5, Canada; Brain Repair Centre, Life Sciences Research Institute, Halifax, Nova Scotia B3H 4R2, Canada.
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15
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Adami R, Bottai D. Spinal Muscular Atrophy Modeling and Treatment Advances by Induced Pluripotent Stem Cells Studies. Stem Cell Rev Rep 2020; 15:795-813. [PMID: 31863335 DOI: 10.1007/s12015-019-09910-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Spinal Muscular Atrophy (SMA) is a neurodegenerative disease characterized by specific and predominantly lower motor neuron (MN) loss. SMA is the main reason for infant death, while about one in 40 children born is a healthy carrier. SMA is caused by decreased levels of production of a ubiquitously expressed gene: the survival motor neuron (SMN). All SMA patients present mutations of the telomeric SMN1 gene, but many copies of a centromeric, partially functional paralog gene, SMN2, can somewhat compensate for the SMN1 deficiency, scaling inversely with phenotypic harshness. Because the study of neural tissue in and from patients presents too many challenges and is very often not feasible; the use of animal models, such as the mouse, had a pivotal impact in our understanding of SMA pathology but could not portray totally satisfactorily the elaborate regulatory mechanisms that are present in higher animals, particularly in humans. And while recent therapeutic achievements have been substantial, especially for very young infants, some issues should be considered for the treatment of older patients. An alternative way to study SMA, and other neurological pathologies, is the use of induced pluripotent stem cells (iPSCs) derived from patients. In this work, we will present a wide analysis of the uses of iPSCs in SMA pathology, starting from basic science to their possible roles as therapeutic tools.
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Affiliation(s)
- Raffaella Adami
- Department of Health Sciences, University of Milan, via A. di Rudinì 8, 20142, Milan, Italy
| | - Daniele Bottai
- Department of Health Sciences, University of Milan, via A. di Rudinì 8, 20142, Milan, Italy.
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16
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Ojeda J, Bermedo-García F, Pérez V, Mella J, Hanna P, Herzberg D, Tejero R, López-Manzaneda M, Tabares L, Henríquez JP. The Mouse Levator Auris Longus Muscle: An Amenable Model System to Study the Role of Postsynaptic Proteins to the Maintenance and Regeneration of the Neuromuscular Synapse. Front Cell Neurosci 2020; 14:225. [PMID: 32848618 PMCID: PMC7405910 DOI: 10.3389/fncel.2020.00225] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 06/26/2020] [Indexed: 12/16/2022] Open
Abstract
The neuromuscular junction (NMJ) is the peripheral synapse that controls the coordinated movement of many organisms. The NMJ is also an archetypical model to study synaptic morphology and function. As the NMJ is the primary target of neuromuscular diseases and traumatic injuries, the establishment of suitable models to study the contribution of specific postsynaptic muscle-derived proteins on NMJ maintenance and regeneration is a permanent need. Considering the unique experimental advantages of the levator auris longus (LAL) muscle, here we present a method allowing for efficient electroporation-mediated gene transfer and subsequent detailed studies of the morphology and function of the NMJ and muscle fibers. Also, we have standardized efficient facial nerve injury protocols to analyze LAL muscle NMJ degeneration and regeneration. Our results show that the expression of a control fluorescent protein does not alter either the muscle structural organization, the apposition of the pre- and post-synaptic domains, or the functional neurotransmission parameters of the LAL muscle NMJs; in turn, the overexpression of MuSK, a major regulator of postsynaptic assembly, induces the formation of ectopic acetylcholine receptor clusters. Our NMJ denervation experiments showed complete reinnervation of LAL muscle NMJs four weeks after facial nerve injury. Together, these experimental strategies in the LAL muscle constitute effective methods to combine protein expression with accurate analyses at the levels of structure, function, and regeneration of the NMJ.
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Affiliation(s)
- Jorge Ojeda
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile.,Department of Medical Physiology and Biophysics, School of Medicine, Universidad de Sevilla, Sevilla, Spain.,Developmental Neurobiology Unit, Biomedical Sciences Research Laboratory, Basic Sciences Department, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Francisca Bermedo-García
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile
| | - Viviana Pérez
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile
| | - Jessica Mella
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile
| | - Patricia Hanna
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile
| | - Daniel Herzberg
- Veterinary Sciences Clinic, Universidad de Concepción, Concepción, Chile
| | - Rocío Tejero
- Department of Medical Physiology and Biophysics, School of Medicine, Universidad de Sevilla, Sevilla, Spain
| | - Mario López-Manzaneda
- Department of Medical Physiology and Biophysics, School of Medicine, Universidad de Sevilla, Sevilla, Spain
| | - Lucia Tabares
- Department of Medical Physiology and Biophysics, School of Medicine, Universidad de Sevilla, Sevilla, Spain
| | - Juan Pablo Henríquez
- Neuromuscular Studies Laboratory (NeSt Lab), Department of Cell Biology, Faculty of Biological Sciences, Center for Advanced Microscopy (CMA BioBio), Universidad de Concepción, Concepción, Chile
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17
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Boehm I, Alhindi A, Leite AS, Logie C, Gibbs A, Murray O, Farrukh R, Pirie R, Proudfoot C, Clutton R, Wishart TM, Jones RA, Gillingwater TH. Comparative anatomy of the mammalian neuromuscular junction. J Anat 2020; 237:827-836. [PMID: 32573802 PMCID: PMC7542190 DOI: 10.1111/joa.13260] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 12/11/2022] Open
Abstract
The neuromuscular junction (NMJ)—a synapse formed between lower motor neuron and skeletal muscle fibre—represents a major focus of both basic neuroscience research and clinical neuroscience research. Although the NMJ is known to play an important role in many neurodegenerative conditions affecting humans, the vast majority of anatomical and physiological data concerning the NMJ come from lower mammalian (e.g. rodent) animal models. However, recent findings have demonstrated major differences between the cellular anatomy and molecular anatomy of human and rodent NMJs. Therefore, we undertook a comparative morphometric analysis of the NMJ across several larger mammalian species in order to generate baseline inter‐species anatomical reference data for the NMJ and to identify animal models that better represent the morphology of the human NMJ in vivo. Using a standardized morphometric platform (‘NMJ‐morph’), we analysed 5,385 individual NMJs from lower/pelvic limb muscles (EDL, soleus and peronei) of 6 mammalian species (mouse, cat, dog, sheep, pig and human). There was marked heterogeneity of NMJ morphology both within and between species, with no overall relationship found between NMJ morphology and muscle fibre diameter or body size. Mice had the largest NMJs on the smallest muscle fibres; cats had the smallest NMJs on the largest muscle fibres. Of all the species examined, the sheep NMJ had the most closely matched morphology to that found in humans. Taken together, we present a series of comprehensive baseline morphometric data for the mammalian NMJ and suggest that ovine models are likely to best represent the human NMJ in health and disease.
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Affiliation(s)
- 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
| | - Abrar Alhindi
- School of Medicine, UNESP-São Paulo State University, Botucatu, Sao Paulo, Brazil.,Faculty of Medicine, Department of Anatomy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ana S Leite
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK.,School of Medicine, UNESP-São Paulo State University, Botucatu, Sao Paulo, Brazil
| | - Chandra Logie
- The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, UK
| | - Alyssa Gibbs
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Olivia Murray
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Rizwan Farrukh
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Robert Pirie
- The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, UK
| | | | - Richard Clutton
- The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, UK
| | - Thomas M Wishart
- The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, UK
| | - Ross A Jones
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, UK
| | - Thomas H Gillingwater
- 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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18
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Reduced TUBA1A Tubulin Causes Defects in Trafficking and Impaired Adult Motor Behavior. eNeuro 2020; 7:ENEURO.0045-20.2020. [PMID: 32184299 PMCID: PMC7218002 DOI: 10.1523/eneuro.0045-20.2020] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/03/2020] [Indexed: 12/30/2022] Open
Abstract
Newly born neurons express high levels of TUBA1A α-tubulin to assemble microtubules for neurite extension and to provide tracks for intracellular transport. In the adult brain, Tuba1a expression decreases dramatically. A mouse that harbors a loss-of-function mutation in the gene encoding TUBA1A (Tuba1aND/+) allows us to ask whether TUBA1A is important for the function of mature neurons. α-Tubulin levels are about half of wild type in juvenile Tuba1aND/+ brains, but are close to normal in older animals. In postnatal day (P)0 cultured neurons, reduced TUBA1A allows for assembly of less microtubules in axons resulting in more pausing during organelle trafficking. While Tuba1aND/+ mouse behavior is indistinguishable from wild-type siblings at weaning, Tuba1aND/+ mice develop adult-onset ataxia. Neurons important for motor function in Tuba1aND/+ remain indistinguishable from wild-type with respect to morphology and number and display no evidence of axon degeneration. Tuba1aND/+ neuromuscular junction (NMJ) synapses are the same size as wild-type before the onset of ataxia, but are reduced in size in older animals. Together, these data indicate that the TUBA1A-rich microtubule tracks that are assembled during development are essential for mature neuron function and maintenance of synapses over time.
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19
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Minty G, Hoppen A, Boehm I, Alhindi A, Gibb L, Potter E, Wagner BC, Miller J, Skipworth RJE, Gillingwater TH, Jones RA. aNMJ-morph: a simple macro for rapid analysis of neuromuscular junction morphology. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200128. [PMID: 32431902 PMCID: PMC7211862 DOI: 10.1098/rsos.200128] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 03/23/2020] [Indexed: 06/11/2023]
Abstract
Large-scale data analysis of synaptic morphology is becoming increasingly important to the field of neurobiological research (e.g. 'connectomics'). In particular, a detailed knowledge of neuromuscular junction (NMJ) morphology has proven to be important for understanding the form and function of synapses in both health and disease. The recent introduction of a standardized approach to the morphometric analysis of the NMJ-'NMJ-morph'-has provided the first common software platform with which to analyse and integrate NMJ data from different research laboratories. Here, we describe the design and development of a novel macro-'automated NMJ-morph' or 'aNMJ-morph'-to update and streamline the original NMJ-morph methodology. ImageJ macro language was used to encode the complete NMJ-morph workflow into seven navigation windows that generate robust data for 19 individual pre-/post-synaptic variables. The aNMJ-morph scripting was first validated against reference data generated by the parent workflow to confirm data reproducibility. aNMJ-morph was then compared with the parent workflow in large-scale data analysis of original NMJ images (240 NMJs) by multiple independent investigators. aNMJ-morph conferred a fourfold increase in data acquisition rate compared with the parent workflow, with average analysis times reduced to approximately 1 min per NMJ. Strong concordance was demonstrated between the two approaches for all 19 morphological variables, confirming the robust nature of aNMJ-morph. aNMJ-morph is a freely available and easy-to-use macro for the rapid and robust analysis of NMJ morphology and offers significant improvements in data acquisition and learning curve compared to the original NMJ-morph workflow.
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Affiliation(s)
- Gavin Minty
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Alex Hoppen
- RWTH Aachen University, 52062 Aachen, Germany
| | - Ines Boehm
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Abrar Alhindi
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Larissa Gibb
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Ellie Potter
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Boris C. Wagner
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Janice Miller
- Clinical Surgery, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, EH16 4SA, UK
| | - Richard J. E. Skipworth
- Clinical Surgery, University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, EH16 4SA, UK
| | - Thomas H. Gillingwater
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Ross A. Jones
- Edinburgh Medical School: Biomedical Sciences (Anatomy), University of Edinburgh, Edinburgh EH8 9AG, UK
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
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20
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Arakawa M, Wagatsuma A. 1α, 25(OH) 2D 3 regulates agrin-induced acetylcholine receptor clustering through upregulation of rapsyn expression in C2C12 myotubes. Biochem Biophys Res Commun 2020; 525:S0006-291X(20)30293-X. [PMID: 32081417 DOI: 10.1016/j.bbrc.2020.02.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 02/04/2020] [Indexed: 12/26/2022]
Abstract
The active form of vitamin D (1α, 25-dihydroxyvitamin D3 [1α, 25(OH)2D3], referred to as 1,25D) has been suggested to play a pivotal role in skeletal muscle function and metabolism. However, the mechanisms through which 1,25D functions in this tissue remain to be elucidated. Recent studies have shown that vitamin D signaling regulates neuromuscular maintenance and improves locomotion in mice. In the present study, we examined the effects of 1,25D on neuromuscular synaptogenesis by measuring clustering of acetylcholine receptors (AChRs) in C2C12 myotubes. 1,25D treatment enhanced the agrin-induced AChR clustering in myotubes compared to treatment with agrin alone. Furthermore, siRNA-mediated knockdown of the vitamin D receptor (VDR) decreased the agrin-induced AChR clustering. 1,25D increased the expression of rapsyn, which is necessary for AChR clustering, while demonstrating no effect on other neuromuscular junction-related genes. In addition, rapsyn expression was dependent on 1,25D-VDR signaling. These results suggest that 1,25D-VDR signaling may regulate rapsin expression, resulting in the up-regulation of agrin-induced AChR clustering.
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Affiliation(s)
- Masayuki Arakawa
- Laboratory of Virology, Institute of Microbial Chemistry, 5-14-23 Kamiosaki, Shinagawa-ku, Tokyo, 141-0021, Japan
| | - Akira Wagatsuma
- Laboratory of Muscle Biology, Tokyo Woman's Christian University, 2-6-1 Zempukuji, Suginami-ku, Tokyo, 167-8585, Japan.
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21
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Martínez-Muriana A, Pastor D, Mancuso R, Rando A, Osta R, Martínez S, López-Vales R, Navarro X. Combined intramuscular and intraspinal transplant of bone marrow cells improves neuromuscular function in the SOD1 G93A mice. Stem Cell Res Ther 2020; 11:53. [PMID: 32033585 PMCID: PMC7006400 DOI: 10.1186/s13287-020-1573-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 01/13/2020] [Accepted: 01/27/2020] [Indexed: 12/11/2022] Open
Abstract
Background The simultaneous contribution of several etiopathogenic disturbances makes amyotrophic lateral sclerosis (ALS) a fatal and challenging disease. Here, we studied two different cell therapy protocols to protect both central and peripheral nervous system in a murine model of ALS. Methods Since ALS begins with a distal axonopathy, in a first assay, we performed injection of bone marrow cells into two hindlimb muscles of transgenic SOD1G93A mice. In a second study, we combined intramuscular and intraspinal injection of bone marrow cells. Fluorescence-activated cell sorting was used to assess the survival of the transplanted cells into the injected tissues. The mice were assessed from 8 to 16 weeks of age by means of locomotion and electrophysiological tests. After follow-up, the spinal cord was processed for analysis of motoneuron survival and glial cell reactivity. Results We found that, after intramuscular injection, bone marrow cells were able to engraft within the muscle. However, bone marrow cell intramuscular injection failed to promote a general therapeutic effect. In the second approach, we found that bone marrow cells had limited survival in the spinal cord, but this strategy significantly improved motor outcomes. Moreover, we also found that the dual cell therapy tended to preserve spinal motoneurons at late stages of the disease and to reduce microgliosis, although this did not prolong mice survival. Conclusion Overall, our findings suggest that targeting more than one affected area of the motor system at once with bone marrow cell therapy results in a valuable therapeutic intervention for ALS.
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Affiliation(s)
- Anna Martínez-Muriana
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Diego Pastor
- Centro de Investigación Deportiva, Universidad Miguel Hernández, Elche, Spain.,Instituto de Neurociencias, UMH-CSIC, San Juan de Alicante, Spain
| | - Renzo Mancuso
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain.,VIB Center for Brain and Disease Research, KU Leuven, Leuven, Belgium
| | - Amaya Rando
- Laboratory of Genetic Biochemistry (LAGENBIO), Health Research Institute of Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Rosario Osta
- Laboratory of Genetic Biochemistry (LAGENBIO), Health Research Institute of Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | | | - Rubèn López-Vales
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Xavier Navarro
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain. .,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain. .,Faculty of Medicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
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22
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Vila OF, Qu Y, Vunjak-Novakovic G. In vitro models of neuromuscular junctions and their potential for novel drug discovery and development. Expert Opin Drug Discov 2019; 15:307-317. [PMID: 31846349 DOI: 10.1080/17460441.2020.1700225] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Introduction: Neuromuscular Junctions (NMJs) are the synapses between motor neurons and skeletal muscle fibers, and they are responsible for voluntary motor function. NMJs are affected at early stages of numerous neurodegenerative and neuroimmunological diseases. Due to the difficulty of systematically studying and manipulating NMJs in live subjects, in vitro systems with human tissue models would provide a powerful complement to simple cell cultures and animal models for mechanistic and drug development studies.Areas covered: The authors review the latest advances in in vitro models of NMJs, from traditional cell co-culture systems to novel tissue culture approaches, with focus on disease modeling and drug testing.Expert opinion: In recent years, more sophisticated in vitro models of human NMJs have been established. The combination of human stem cell technology with advanced tissue culture systems has resulted in systems that better recapitulate the human NMJ structure and function, and thereby allow for high-throughput quantitative functional measurements under both healthy and diseased conditions. Although they still have limitations, these advanced systems are increasingly demonstrating their utility for evaluating new therapies for motoneuron and autoimmune neuromuscular diseases, and we expect them to become an integral part of the drug discovery process in the near future.
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Affiliation(s)
- Olaia F Vila
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Yihuai Qu
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
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23
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Günther R, Wurster CD, Cordts I, Koch JC, Kamm C, Petzold D, Aust E, Deschauer M, Lingor P, Ludolph AC, Hermann A. Patient-Reported Prevalence of Non-motor Symptoms Is Low in Adult Patients Suffering From 5q Spinal Muscular Atrophy. Front Neurol 2019; 10:1098. [PMID: 31736847 PMCID: PMC6838202 DOI: 10.3389/fneur.2019.01098] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 10/01/2019] [Indexed: 12/14/2022] Open
Abstract
Background: 5q spinal muscular atrophy (SMA) is an autosomal recessive lower motoneuron disease caused by deletion or mutations in the survival motor neuron 1 gene (SMN1) which results in reduced expression of full-length SMN protein. The main symptoms are caused by spinal motor neuron demise leading to muscle atrophy, and medical care mostly refers to motor symptoms. However, new insights of recent studies in severe SMA type I revealed disease involvement of several non-motor regions, for example cardiac, vascular, sensory nerve involvement, and thalamic lesions. Non-motor symptoms (NMS) were previously described in many neurodegenerative diseases i.e., Parkinson's disease and, importantly, also amyotrophic lateral sclerosis. Methods: We screened for NMS in 70 adult patients with SMA type II (SMAII) and type III (SMAIII) and 59 age/sex-matched healthy controls (controls) in a multicenter cross-sectional study including 5 different centers with specialized expertise in medical health care of motoneuron diseases. We used a self-rating questionnaire including 30 different items of gastrointestinal, autonomic, neuropsychiatric, and sleep complaints [NMS questionnaire (NMSQuest)], which is a validated tool in Parkinson's disease. Results: Total NMS burden was low in adult SMA (median: 3 items) and not significantly different compared to controls (median: 2 items). Total NMS of SMA patients did not correlate with disease severity scores. However, the items "swallowing difficulties," "falling," and particularly "swelling legs" were significantly more frequently reported in SMA. Neuropsychiatric symptoms were reported in a frequency comparable to controls and were not significantly increased in SMA. Conclusion: Patient-reported prevalence of NMS in adult SMA was low, which does not argue for a clinically relevant multisystemic disorder in SMAII/III. Importantly, adult SMA patients do not seem to suffer more frequently from symptoms of depression or adaptive disorders compared to controls. Our results yield novel information on previously underreported symptoms and will help to improve the medical guidance of these patients.
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Affiliation(s)
- René Günther
- Department of Neurology, Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases Dresden, Dresden, Germany
| | | | - Isabell Cordts
- Department of Neurology, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | - Jan Christoph Koch
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Christoph Kamm
- Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Daniel Petzold
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Elisa Aust
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Marcus Deschauer
- Department of Neurology, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | - Paul Lingor
- Department of Neurology, Technical University of Munich, School of Medicine, Klinikum rechts der Isar, Munich, Germany
| | - Albert Christian Ludolph
- Department of Neurology, Ulm University, Ulm, Germany.,German Center for Neurodegenerative Diseases Ulm, Ulm, Germany
| | - Andreas Hermann
- Translational Neurodegeneration Section "Albrecht-Kossel", Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany.,German Center for Neurodegenerative Diseases Rostock, Rostock, Germany
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24
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Walters R, Manion J, Neely GG. Dissecting Motor Neuron Disease With Drosophila melanogaster. Front Neurosci 2019; 13:331. [PMID: 31031583 PMCID: PMC6473072 DOI: 10.3389/fnins.2019.00331] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 03/21/2019] [Indexed: 12/13/2022] Open
Abstract
Motor Neuron Disease (MND) typically affects patients during the later stages of life, and thus, MND is having an increasingly devastating impact on diagnosed individuals, their families and society. The umbrella term MND refers to diseases which cause the progressive loss of upper and/or lower motor neurons and a subsequent decrease in motor ability such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA). The study of these diseases is complex and has recently involved the use of genome-wide association studies (GWAS). However, in the case of MND, it has been difficult to identify the complex genetics involved in subtypes, and functional investigation of new candidate disease genes is warranted. Drosophila is a powerful model for addressing these complex diseases. The UAS/Gal4/Gal80 system allows for the upregulation of Drosophila genes, the “knockdown” of genes and the ectopic expression of human genes or mutations in a tissue-specific manner; often resulting in Drosophila models which exhibit typical MND disease pathologies. These can then be further interrogated to identify disease-modifying genes or mutations and disease pathways. This review will discuss two common MNDs and the current Drosophila models which are being used to research their genetic basis and the different pathologies of MND.
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Affiliation(s)
- Rachel Walters
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - John Manion
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - G Gregory Neely
- Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
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25
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Ko E, Yu SJ, Pagan‐Diaz GJ, Mahmassani Z, Boppart MD, Im SG, Bashir R, Kong H. Matrix Topography Regulates Synaptic Transmission at the Neuromuscular Junction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2019; 6:1801521. [PMID: 30937256 PMCID: PMC6425454 DOI: 10.1002/advs.201801521] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/26/2018] [Indexed: 05/19/2023]
Abstract
Recreation of a muscle that can be controlled by the nervous system would provide a major breakthrough for treatments of injury and diseases. However, the underlying basis of how neuron-muscle interfaces are formed is still not understood sufficiently. Here, it is hypothesized that substrate topography regulates neural innervation and synaptic transmission by mediating the cross-talk between neurons and muscles. This hypothesis is examined by differentiating neural stem cells on the myotubes, formed on the substrate with controlled groove width. The substrate with the groove width of 1600 nm, a similar size to the myofibril diameter, serves to produce larger and aligned myotubes than the flat substrate. The myotubes formed on the grooved substrate display increases in the acetylcholine receptor expression. Reciprocally, motor neuron progenitor cells differentiated from neural stem cells innervate the larger and aligned myotubes more actively than randomly oriented myotubes. As a consequence, mature and aligned myotubes respond to glutamate (i.e., an excitatory neurotransmitter) and curare (i.e., a neuromuscular antagonist) more rapidly and homogeneously than randomly oriented myotubes. The results of this study will be broadly useful for improving the quality of engineered muscle used in a series of applications including drug screening, regeneration therapies, and biological machinery assembly.
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Affiliation(s)
- Eunkyung Ko
- Department of BioengineeringUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Department of BioengineeringMicro and Nanotechnology LaboratoryUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
| | - Seung Jung Yu
- Department of Chemical and Biomolecular Engineering and KI for the Nano CenturyKorea Advanced Institute of Science and Technology (KAIST)Daejeon305‐701Republic of Korea
| | - Gelson J. Pagan‐Diaz
- Department of BioengineeringMicro and Nanotechnology LaboratoryUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
| | - Ziad Mahmassani
- Department of Kinesiology and Community HealthBeckman Institute for Advanced Science and TechnologyUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
| | - Marni D. Boppart
- Department of Kinesiology and Community HealthBeckman Institute for Advanced Science and TechnologyUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
| | - Sung Gap Im
- Department of Chemical and Biomolecular Engineering and KI for the Nano CenturyKorea Advanced Institute of Science and Technology (KAIST)Daejeon305‐701Republic of Korea
| | - Rashid Bashir
- Department of BioengineeringMicro and Nanotechnology LaboratoryUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Carl R. Woese Institute for Genomic Biology and Beckman Institute for Advanced Science and TechnologyUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Carle Illinois College of MedicineUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
| | - Hyunjoon Kong
- Department of BioengineeringUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Carl R. Woese Institute for Genomic Biology and Beckman Institute for Advanced Science and TechnologyUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Carle Illinois College of MedicineUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
- Department of Chemical and Biomolecular EngineeringUniversity of Illinois at Urbana–ChampaignUrbanaIL61801USA
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26
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Bioinspired Three-Dimensional Human Neuromuscular Junction Development in Suspended Hydrogel Arrays. Tissue Eng Part C Methods 2019; 24:346-359. [PMID: 29739270 DOI: 10.1089/ten.tec.2018.0062] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The physical connection between motoneurons and skeletal muscle targets is responsible for the creation of neuromuscular junctions (NMJs), which allow electrical signals to be translated to mechanical work. NMJ pathology contributes to the spectrum of neuromuscular, motoneuron, and dystrophic disease. Improving in vitro tools that allow for recapitulation of the physiology of the neuromuscular connection will enable researchers to better understand the development and maturation of NMJs, and will help to decipher mechanisms leading to NMJ degeneration. In this work, we first describe robust differentiation of bungarotoxin-positive human myotubes, as well as a reproducible method for encapsulating and aligning human myoblasts in three-dimensional (3D) suspended culture using bioprinted silk fibroin cantilevers as cell culture supports. Further analysis with coculture of motoneuron-like cells demonstrates feasibility of fully human coculture using two-dimensional and 2.5-dimensional culture methods, with appropriate differentiation of both cell types. Using these coculture differentiation conditions with motoneuron-like cells added to monocultures of 3D suspended human myotubes, we then demonstrate synaptic colocalization in coculture as well as acetylcholine and glutamic acid stimulation of human myocytes. This method represents a unique platform to coculture suspended human myoblast-seeded 3D hydrogels with integrated motoneuron-like cells derived from human induced neural stem cells. The platform described is fully customizable using 3D freeform printing into standard laboratory tissue culture materials, and allows for human myoblast alignment in 3D with precise motoneuron integration into preformed myotubes. The coculture method will ideally be useful in observation and analysis of neurite outgrowth and myogenic differentiation in 3D with quantification of several parameters of muscle innervation and function.
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27
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Vila OF, Uzel SG, Ma SP, Williams D, Pak J, Kamm RD, Vunjak-Novakovic G. Quantification of human neuromuscular function through optogenetics. Am J Cancer Res 2019; 9:1232-1246. [PMID: 30867827 PMCID: PMC6401498 DOI: 10.7150/thno.25735] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 12/23/2018] [Indexed: 01/15/2023] Open
Abstract
The study of human neuromuscular diseases has traditionally been performed in animal models, due to the difficulty of performing studies in human subjects. Despite the unquestioned value of animal models, inter-species differences hamper the translation of these findings to clinical trials. Tissue-engineered models of the neuromuscular junction (NMJ) allow for the recapitulation of the human physiology in tightly controlled in vitro settings. Methods: Here we report the first human patient-specific tissue-engineered model of the neuromuscular junction (NMJ) that combines stem cell technology with tissue engineering, optogenetics, microfabrication and image processing. The combination of custom-made hardware and software allows for repeated, quantitative measurements of NMJ function in a user-independent manner. Results: We demonstrate the utility of this model for basic and translational research by characterizing in real time the functional changes during physiological and pathological processes. Principal Conclusions: This system holds great potential for the study of neuromuscular diseases and drug screening, allowing for the extraction of quantitative functional data from a human, patient-specific system.
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28
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So E, Mitchell JC, Memmi C, Chennell G, Vizcay-Barrena G, Allison L, Shaw CE, Vance C. Mitochondrial abnormalities and disruption of the neuromuscular junction precede the clinical phenotype and motor neuron loss in hFUSWT transgenic mice. Hum Mol Genet 2019; 27:463-474. [PMID: 29194538 PMCID: PMC5886082 DOI: 10.1093/hmg/ddx415] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/26/2017] [Indexed: 11/16/2022] Open
Abstract
FUS (fused in sarcoma) mislocalization and cytoplasmic aggregation are hallmark pathologies in FUS-related amyotrophic lateral sclerosis and frontotemporal dementia. Many of the mechanistic hypotheses have focused on a loss of nuclear function in the FUS-opathies, implicating dysregulated RNA transcription and splicing in driving neurodegeneration. Recent studies describe an additional somato-dendritic localization for FUS in the cerebral cortex implying a regulatory role in mRNA transport and local translation at the synapse. Here, we report that FUS is also abundant at the pre-synaptic terminal of the neuromuscular junction (NMJ), suggesting an important function for this protein at peripheral synapses. We have previously reported dose and age-dependent motor neuron degeneration in transgenic mice overexpressing human wild-type FUS, resulting in a motor phenotype detected by ∼28 days and death by ∼100 days. Now, we report the earliest structural events using electron microscopy and quantitative immunohistochemistry. Mitochondrial abnormalities in the pre-synaptic motor nerve terminals are detected at postnatal day 6, which are more pronounced at P15 and accompanied by a loss of synaptic vesicles and synaptophysin protein coupled with NMJs of a smaller size at a time when there is no detectable motor neuron loss. These changes occur in the presence of abundant FUS and support a peripheral toxic gain of function. This appearance is typical of a ‘dying-back’ axonopathy, with the earliest manifestation being mitochondrial disruption. These findings support our hypothesis that FUS has an important function at the NMJ, and challenge the ‘loss of nuclear function’ hypothesis for disease pathogenesis in the FUS-opathies.
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Affiliation(s)
- Eva So
- Department of Basic and Clinical Neuroscience
| | | | | | - George Chennell
- Department of Basic and Clinical Neuroscience.,Wohl Cellular Imaging Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Denmark Hill, London SE5 8AF, UK
| | - Gema Vizcay-Barrena
- Centre for Ultrastructural Imaging, King's College London, New Hunts House, Guy's Campus, London SE1 1UL, UK
| | - Leanne Allison
- Centre for Ultrastructural Imaging, King's College London, New Hunts House, Guy's Campus, London SE1 1UL, UK
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29
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30
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Cellular and Molecular Anatomy of the Human Neuromuscular Junction. Cell Rep 2018; 21:2348-2356. [PMID: 29186674 PMCID: PMC5723673 DOI: 10.1016/j.celrep.2017.11.008] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/18/2017] [Accepted: 11/01/2017] [Indexed: 12/20/2022] Open
Abstract
The neuromuscular junction (NMJ) plays a fundamental role in transferring information from lower motor neuron to skeletal muscle to generate movement. It is also an experimentally accessible model synapse routinely studied in animal models to explore fundamental aspects of synaptic form and function. Here, we combined morphological techniques, super-resolution imaging, and proteomic profiling to reveal the detailed cellular and molecular architecture of the human NMJ. Human NMJs were significantly smaller, less complex, and more fragmented than mouse NMJs. In contrast to mice, human NMJs were also remarkably stable across the entire adult lifespan, showing no signs of age-related degeneration or remodeling. Super-resolution imaging and proteomic profiling revealed distinctive distribution of active zone proteins and differential expression of core synaptic proteins and molecular pathways at the human NMJ. Taken together, these findings reveal human-specific cellular and molecular features of the NMJ that distinguish them from comparable synapses in other mammalian species.
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31
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Collagen XIII Is Required for Neuromuscular Synapse Regeneration and Functional Recovery after Peripheral Nerve Injury. J Neurosci 2018; 38:4243-4258. [PMID: 29626165 DOI: 10.1523/jneurosci.3119-17.2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 03/02/2018] [Accepted: 03/30/2018] [Indexed: 11/21/2022] Open
Abstract
Collagen XIII occurs as both a transmembrane-bound and a shed extracellular protein and is able to regulate the formation and function of neuromuscular synapses. Its absence results in myasthenia: presynaptic and postsynaptic defects at the neuromuscular junction (NMJ), leading to destabilization of the motor nerves, muscle regeneration and atrophy. Mutations in COL13A1 have recently been found to cause congenital myasthenic syndrome, characterized by fatigue and chronic muscle weakness, which may be lethal. We show here that muscle defects in collagen XIII-deficient mice stabilize in adulthood, so that the disease is not progressive until very late. Sciatic nerve crush was performed to examine how the lack of collagen XIII or forced expression of its transmembrane form affects the neuromuscular synapse regeneration and functional recovery following injury. We show that collagen XIII-deficient male mice are unable to achieve complete NMJ regeneration and functional recovery. This is mainly attributable to presynaptic defects that already existed in the absence of collagen XIII before injury. Shedding of the ectodomain is not required, as the transmembrane form of collagen XIII alone fully rescues the phenotype. Thus, collagen XIII could serve as a therapeutic agent in cases of injury-induced PNS regeneration and functional recovery. We conclude that intrinsic alterations at the NMJ in Col13a1-/- mice contribute to impaired and incomplete NMJ regeneration and functional recovery after peripheral nerve injury. However, such alterations do not progress once they have stabilized in early adulthood, emphasizing the role of collagen XIII in NMJ maturation.SIGNIFICANCE STATEMENT Collagen XIII is required for gaining and maintaining the normal size, complexity, and functional capacity of neuromuscular synapses. Loss-of-function mutations in COL13A1 cause congenital myasthenic syndrome 19, characterized by postnatally progressive muscle fatigue, which compromises patients' functional capacity. We show here in collagen XIII-deficient mice that the disease stabilizes in adulthood once the NMJs have matured. This study also describes a relevant contribution of the altered NMJ morphology and function to neuromuscular synapses, and PNS regeneration and functional recovery in collagen XIII-deficient mice after peripheral nerve injury. Correlating the animal model data on collagen XIII-associated congenital myasthenic syndrome, it can be speculated that neuromuscular connections in congenital myasthenic syndrome patients are not able to fully regenerate and restore normal functionality if exposed to peripheral nerve injury.
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32
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Miyoshi S, Tezuka T, Arimura S, Tomono T, Okada T, Yamanashi Y. DOK7 gene therapy enhances motor activity and life span in ALS model mice. EMBO Mol Med 2018; 9:880-889. [PMID: 28490573 PMCID: PMC5494517 DOI: 10.15252/emmm.201607298] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive, multifactorial motor neurodegenerative disease with severe muscle atrophy. The glutamate release inhibitor riluzole is the only medication approved by the FDA, and prolongs patient life span by a few months, testifying to a strong need for new treatment strategies. In ALS, motor neuron degeneration first becomes evident at the motor nerve terminals in neuromuscular junctions (NMJs), the cholinergic synapse between motor neuron and skeletal muscle; degeneration then progresses proximally, implicating the NMJ as a therapeutic target. We previously demonstrated that activation of muscle‐specific kinase MuSK by the cytoplasmic protein Dok‐7 is essential for NMJ formation, and forced expression of Dok‐7 in muscle activates MuSK and enlarges NMJs. Here, we show that therapeutic administration of an adeno‐associated virus vector encoding the human DOK7 gene suppressed motor nerve terminal degeneration at NMJs together with muscle atrophy in the SOD1‐G93A ALS mouse model. Ultimately, we show that DOK7 gene therapy enhanced motor activity and life span in ALS model mice.
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Affiliation(s)
- Sadanori Miyoshi
- Division of Genetics, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Tohru Tezuka
- Division of Genetics, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Sumimasa Arimura
- Division of Genetics, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Taro Tomono
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan.,Graduate School of Comprehensive Human Sciences, Majors in Medical Sciences University of Tsukuba, Ibaraki, Japan
| | - Takashi Okada
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Tokyo, Japan
| | - Yuji Yamanashi
- Division of Genetics, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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33
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Small-molecule flunarizine increases SMN protein in nuclear Cajal bodies and motor function in a mouse model of spinal muscular atrophy. Sci Rep 2018; 8:2075. [PMID: 29391529 PMCID: PMC5794986 DOI: 10.1038/s41598-018-20219-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 01/16/2018] [Indexed: 02/07/2023] Open
Abstract
The hereditary neurodegenerative disorder spinal muscular atrophy (SMA) is characterized by the loss of spinal cord motor neurons and skeletal muscle atrophy. SMA is caused by mutations of the survival motor neuron (SMN) gene leading to a decrease in SMN protein levels. The SMN deficiency alters nuclear body formation and whether it can contribute to the disease remains unclear. Here we screen a series of small-molecules on SMA patient fibroblasts and identify flunarizine that accumulates SMN into Cajal bodies, the nuclear bodies important for the spliceosomal small nuclear RNA (snRNA)-ribonucleoprotein biogenesis. Using histochemistry, real-time RT-PCR and behavioural analyses in a mouse model of SMA, we show that along with the accumulation of SMN into Cajal bodies of spinal cord motor neurons, flunarizine treatment modulates the relative abundance of specific spliceosomal snRNAs in a tissue-dependent manner and can improve the synaptic connections and survival of spinal cord motor neurons. The treatment also protects skeletal muscles from cell death and atrophy, raises the neuromuscular junction maturation and prolongs life span by as much as 40 percent (p < 0.001). Our findings provide a functional link between flunarizine and SMA pathology, highlighting the potential benefits of flunarizine in a novel therapeutic perspective against neurodegenerative diseases.
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34
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Boido M, De Amicis E, Valsecchi V, Trevisan M, Ala U, Ruegg MA, Hettwer S, Vercelli A. Increasing Agrin Function Antagonizes Muscle Atrophy and Motor Impairment in Spinal Muscular Atrophy. Front Cell Neurosci 2018; 12:17. [PMID: 29440993 PMCID: PMC5797594 DOI: 10.3389/fncel.2018.00017] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 01/11/2018] [Indexed: 11/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a pediatric genetic disease, characterized by motor neuron (MN) death, leading to progressive muscle weakness, respiratory failure, and, in the most severe cases, to death. Abnormalities at the neuromuscular junction (NMJ) have been reported in SMA, including neurofilament (NF) accumulation at presynaptic terminals, immature and smaller than normal endplates, reduced transmitter release, and, finally, muscle denervation. Here we have studied the role of agrin in SMAΔ7 mice, the experimental model of SMAII. We observed a 50% reduction in agrin expression levels in quadriceps of P10 SMA mice compared to age-matched WT controls. To counteract such condition, we treated SMA mice from birth onwards with therapeutic agrin biological NT-1654, an active splice variant of agrin retaining synaptogenic properties, which is also resistant to proteolytic cleavage by neurotrypsin. Mice were analyzed for behavior, muscle and NMJ histology, and survival. Motor behavior was significantly improved and survival was extended by treatment of SMA mice with NT-1654. At P10, H/E-stained sections of the quadriceps, a proximal muscle early involved in SMA, showed that NT-1654 treatment strongly prevented the size decrease of muscle fibers. Studies of NMJ morphology on whole-mount diaphragm preparations revealed that NT-1654-treated SMA mice had more mature NMJs and reduced NF accumulation, compared to vehicle-treated SMA mice. We conclude that increasing agrin function in SMA has beneficial outcomes on muscle fibers and NMJs as the agrin biological NT-1654 restores the crosstalk between muscle and MNs, delaying muscular atrophy, improving motor performance and extending survival.
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Affiliation(s)
- Marina Boido
- Department of Neuroscience Rita Levi Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy
| | - Elena De Amicis
- Department of Neuroscience Rita Levi Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy
| | - Valeria Valsecchi
- Department of Neuroscience Rita Levi Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy
| | - Marco Trevisan
- Department of Neuroscience Rita Levi Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy
| | - Ugo Ala
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | | | | | - Alessandro Vercelli
- Department of Neuroscience Rita Levi Montalcini, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy.,Department of Neuroscience Rita Levi Montalcini, National Institute of Neuroscience, Turin, Italy
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Liu W, Chakkalakal JV. The Composition, Development, and Regeneration of Neuromuscular Junctions. Curr Top Dev Biol 2018; 126:99-124. [DOI: 10.1016/bs.ctdb.2017.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Patten SA, Aggad D, Martinez J, Tremblay E, Petrillo J, Armstrong GA, La Fontaine A, Maios C, Liao M, Ciura S, Wen XY, Rafuse V, Ichida J, Zinman L, Julien JP, Kabashi E, Robitaille R, Korngut L, Parker JA, Drapeau P. Neuroleptics as therapeutic compounds stabilizing neuromuscular transmission in amyotrophic lateral sclerosis. JCI Insight 2017; 2:97152. [PMID: 29202456 DOI: 10.1172/jci.insight.97152] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 10/17/2017] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a rapidly progressing, fatal disorder with no effective treatment. We used simple genetic models of ALS to screen phenotypically for potential therapeutic compounds. We screened libraries of compounds in C. elegans, validated hits in zebrafish, and tested the most potent molecule in mice and in a small clinical trial. We identified a class of neuroleptics that restored motility in C. elegans and in zebrafish, and the most potent was pimozide, which blocked T-type Ca2+ channels in these simple models and stabilized neuromuscular transmission in zebrafish and enhanced it in mice. Finally, a short randomized controlled trial of sporadic ALS subjects demonstrated stabilization of motility and evidence of target engagement at the neuromuscular junction. Simple genetic models are, thus, useful in identifying promising compounds for the treatment of ALS, such as neuroleptics, which may stabilize neuromuscular transmission and prolong survival in this disease.
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Affiliation(s)
- Shunmoogum A Patten
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada.,INRS Institut Armand-Frappier, Laval, Canada
| | - Dina Aggad
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada.,Institut des Biomolécules Max Mousseron IBMM, UMR 5247, CNRS-Université Montpellier-ENSCM, Montpellier, France
| | - Jose Martinez
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Alberta, Canada
| | - Elsa Tremblay
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,FRQS Groupe de recherche sur le système nerveux central, Montreal, Canada
| | - Janet Petrillo
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Alberta, Canada
| | - Gary Ab Armstrong
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada.,Department of Neurology and Neurosurgery, McGill University and Montreal Neurological Institute, Montreal, Canada
| | - Alexandre La Fontaine
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,FRQS Groupe de recherche sur le système nerveux central, Montreal, Canada
| | - Claudia Maios
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada
| | - Meijiang Liao
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada
| | - Sorana Ciura
- Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, Institut du Cerveau et de la Moelle Épinière (ICM), Paris, France
| | - Xiao-Yan Wen
- Zebrafish Centre for Advanced Drug Discovery & Keenan Research Centre for Biomedical Science, Li Ka Sheng Knowledge Institute, St. Michael's Hospital and Department of Medicine & Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Victor Rafuse
- Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Justin Ichida
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine and Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, University of Southern California, Los Angeles, California, USA
| | - Lorne Zinman
- Department of Neurology, University of Toronto, Sunnybrook Health Sciences Centre,Toronto, Ontario, Canada
| | - Jean-Pierre Julien
- Centre de recherche CERVO, Chemin de la Canardière, Université Laval, Québec City, Canada
| | - Edor Kabashi
- Sorbonne Université, Université Pierre et Marie Curie (UPMC), Université de Paris 06, Institut du Cerveau et de la Moelle Épinière (ICM), Paris, France
| | - Richard Robitaille
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,FRQS Groupe de recherche sur le système nerveux central, Montreal, Canada
| | - Lawrence Korngut
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Alberta, Canada
| | - J Alexander Parker
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada
| | - Pierre Drapeau
- Department of Neuroscience, Université de Montréal, Montréal, Canada.,Centre de recherche du centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada.,FRQS Groupe de recherche sur le système nerveux central, Montreal, Canada
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Trias E, Ibarburu S, Barreto-Núñez R, Varela V, Moura IC, Dubreuil P, Hermine O, Beckman JS, Barbeito L. Evidence for mast cells contributing to neuromuscular pathology in an inherited model of ALS. JCI Insight 2017; 2:95934. [PMID: 29046475 PMCID: PMC5846907 DOI: 10.1172/jci.insight.95934] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 09/11/2017] [Indexed: 12/18/2022] Open
Abstract
Evidence indicates that neuroinflammation contributes to motor neuron degeneration in amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease leading to progressive muscular paralysis. However, it remains elusive whether inflammatory cells can interact with degenerating distal motor axons, influencing the progressive denervation of neuromuscular junctions (NMJs). By analyzing the muscle extensor digitorum longus (EDL) following paralysis onset in the SOD1G93A rat model, we have observed a massive infiltration and degranulation of mast cells, starting after paralysis onset and correlating with progressive NMJ denervation. Remarkably, mast cells accumulated around degenerating motor axons and NMJs, and were also associated with macrophages. Mast cell accumulation and degranulation in paralytic EDL muscle was prevented by systemic treatment over 15 days with masitinib, a tyrosine kinase inhibitor currently in clinical trials for ALS exhibiting pharmacological activity affecting mast cells and microglia. Masitinib-induced mast cell reduction resulted in a 35% decrease in NMJ denervation and reduced motor deficits as compared with vehicle-treated rats. Masitinib also normalized macrophage infiltration, as well as regressive changes in Schwann cells and capillary networks observed in advanced paralysis. These findings provide evidence for mast cell contribution to distal axonopathy and paralysis progression in ALS, a mechanism that can be therapeutically targeted by masitinib.
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Affiliation(s)
| | | | | | | | - Ivan C. Moura
- Imagine Institute, Hôpital Necker, Paris, France
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France
- Paris Descartes–Sorbonne Paris Cité University, Imagine Institute, Paris, France
- CNRS ERL 8254, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
- Equipe Labélisée par la Ligue Nationale contre le cancer, Parisa, France
| | - Patrice Dubreuil
- Equipe Labélisée par la Ligue Nationale contre le cancer, Parisa, France
- AB Science, Paris, France
- Signaling, Hematopoiesis and Mechanism of Oncogenesis, Cancer Research Center of Marseille (CRCM), Inserm U1068, Institut Paoli-Calmettes, Aix-Marseille University UM105, CNRS UMR7258, Marseille, France
| | - Olivier Hermine
- Imagine Institute, Hôpital Necker, Paris, France
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France
- Paris Descartes–Sorbonne Paris Cité University, Imagine Institute, Paris, France
- CNRS ERL 8254, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
- Equipe Labélisée par la Ligue Nationale contre le cancer, Parisa, France
- AB Science, Paris, France
- Department of Hematology, Necker Hospital, Paris, France
- Centre national de référence des mastocytoses (CEREMAST), Paris, France
| | - Joseph S. Beckman
- Linus Pauling Institute, Department of Biochemistry and Biophysics, Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, USA
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Defects in Neuromuscular Transmission May Underlie Motor Dysfunction in Spinal and Bulbar Muscular Atrophy. J Neurosci 2017; 36:5094-106. [PMID: 27147661 DOI: 10.1523/jneurosci.3485-15.2016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 03/22/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Spinal and bulbar muscular atrophy (SBMA) in men is an androgen-dependent neuromuscular disease caused by expanded CAG repeats in the androgen receptor (AR). Whether muscle or motor neuron dysfunction or both underlies motor impairment in SBMA is unknown. Muscles of SBMA mice show significant contractile dysfunction, implicating them as a likely source of motor dysfunction, but whether disease also impairs neuromuscular transmission is an open question. Thus, we examined synaptic function in three well-studied SBMA mouse models-the AR97Q, knock-in (KI), and myogenic141 models-by recording in vitro miniature and evoked end-plate potentials (MEPPs and EPPs, respectively) intracellularly from adult muscle fibers. We found striking defects in neuromuscular transmission suggesting that toxic AR in SBMA impairs both presynaptic and postsynaptic mechanisms. Notably, SBMA causes neuromuscular synapses to become weak and muscles to become hyperexcitable in all three models. Presynaptic defects included deficits in quantal content, reduced size of the readily releasable pool, and impaired short-term facilitation. Postsynaptic defects included prolonged decay times for both MEPPs and EPPs, marked resistance to μ-conotoxin (a sodium channel blocker), and enhanced membrane excitability. Quantitative PCR revealed robust upregulation of mRNAs encoding neonatal isoforms of the AChR (γ-subunit) and the voltage-gated sodium channel (NaV1.5) in diseased adult muscles of all three models, consistent with the observed slowing of synaptic potentials and resistance to μ-conotoxin. These findings suggest that muscles of SBMA patients regress to an immature state that impairs neuromuscular function. SIGNIFICANCE STATEMENT We have discovered that SBMA is accompanied by marked defects in neuromuscular synaptic transmission involving both presynaptic and postsynaptic mechanisms. For three different mouse models, we find that diseased synapses are weak, having reduced quantal content due to reductions in the size of the readily releasable pool and/or probability of release. Synaptic potentials in diseased adult fibers are slowed, explained by an aberrant upregulation of the neonatal isoform of the acetylcholine receptor. Diseased fibers also show marked resistance to μ-conotoxin, explained by an aberrant upregulation in the neonatal isoform of the sodium channel, and are hyperexcitable, reminiscent of myotonic dystrophy, showing anode-break action potentials. This work identifies several new molecular targets for recovering function in SBMA.
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Herranz-Martin S, Chandran J, Lewis K, Mulcahy P, Higginbottom A, Walker C, Valenzuela IMPY, Jones RA, Coldicott I, Iannitti T, Akaaboune M, El-Khamisy SF, Gillingwater TH, Shaw PJ, Azzouz M. Viral delivery of C9orf72 hexanucleotide repeat expansions in mice leads to repeat-length-dependent neuropathology and behavioural deficits. Dis Model Mech 2017; 10:859-868. [PMID: 28550099 PMCID: PMC5536911 DOI: 10.1242/dmm.029892] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/23/2017] [Indexed: 01/14/2023] Open
Abstract
Intronic GGGGCC repeat expansions in C9orf72 are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Two major pathologies stemming from the hexanucleotide RNA expansions (HREs) have been identified in postmortem tissue: intracellular RNA foci and repeat-associated non-ATG dependent (RAN) dipeptides, although it is unclear how these and other hallmarks of disease contribute to the pathophysiology of neuronal injury. Here, we describe two novel lines of mice that overexpress either 10 pure or 102 interrupted GGGGCC repeats mediated by adeno-associated virus (AAV) and recapitulate the relevant human pathology and disease-related behavioural phenotypes. Similar levels of intracellular RNA foci developed in both lines of mice, but only mice expressing 102 repeats generated C9orf72 RAN pathology, neuromuscular junction (NMJ) abnormalities, dispersal of the hippocampal CA1, enhanced apoptosis, and deficits in gait and cognition. Neither line of mice, however, showed extensive TAR DNA-binding protein 43 (TDP-43) pathology or neurodegeneration. Our data suggest that RNA foci pathology is not a good predictor of C9orf72 RAN dipeptide formation, and that RAN dipeptides and NMJ dysfunction are drivers of C9orf72 disease pathogenesis. These AAV-mediated models of C9orf72-associated ALS/FTD will be useful tools for studying disease pathophysiology and developing new therapeutic approaches. Summary:C9orf72-linked motor neuron disease models with viral-mediated expression of GGGGCC repeat expansion in mice show neuropathology and behavioural deficits.
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Affiliation(s)
- Saul Herranz-Martin
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Jayanth Chandran
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Katherine Lewis
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Padraig Mulcahy
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Adrian Higginbottom
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Callum Walker
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK.,Department of Molecular Biology and Biotechnology, Krebs and Sheffield Institute for Nucleic Acids, Firth Court, University of Sheffield, Sheffield S10 2TN, UK
| | | | - Ross A Jones
- Centre for Integrative Physiology & Euan MacDonald Centre for Motor Neurone Disease Research, Hugh Robson Building, The University of Edinburgh, 15 George Square, Edinburgh EH8 9XD, UK
| | - Ian Coldicott
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Tommaso Iannitti
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Mohammed Akaaboune
- Molecular, Cellular and Developmental Biology, University of Michigan, 830 North University, Ann Arbor, MI 48109-1048, USA
| | - Sherif F El-Khamisy
- Department of Molecular Biology and Biotechnology, Krebs and Sheffield Institute for Nucleic Acids, Firth Court, University of Sheffield, Sheffield S10 2TN, UK
| | - Thomas H Gillingwater
- Centre for Integrative Physiology & Euan MacDonald Centre for Motor Neurone Disease Research, Hugh Robson Building, The University of Edinburgh, 15 George Square, Edinburgh EH8 9XD, UK
| | - Pamela J Shaw
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
| | - Mimoun Azzouz
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), The University of Sheffield, 385A Glossop Road, Sheffield S10 2HQ, UK
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40
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Hensel N, Claus P. The Actin Cytoskeleton in SMA and ALS: How Does It Contribute to Motoneuron Degeneration? Neuroscientist 2017; 24:54-72. [PMID: 28459188 DOI: 10.1177/1073858417705059] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are neurodegenerative diseases with overlapping clinical phenotypes based on impaired motoneuron function. However, the pathomechanisms of both diseases are largely unknown, and it is still unclear whether they converge on the molecular level. SMA is a monogenic disease caused by low levels of functional Survival of Motoneuron (SMN) protein, whereas ALS involves multiple genes as well as environmental factors. Recent evidence argues for involvement of actin regulation as a causative and dysregulated process in both diseases. ALS-causing mutations in the actin-binding protein profilin-1 as well as the ability of the SMN protein to directly bind to profilins argue in favor of a common molecular mechanism involving the actin cytoskeleton. Profilins are major regulat ors of actin-dynamics being involved in multiple neuronal motility and transport processes as well as modulation of synaptic functions that are impaired in models of both motoneuron diseases. In this article, we review the current literature in SMA and ALS research with a focus on the actin cytoskeleton. We propose a common molecular mechanism that explains the degeneration of motoneurons for SMA and some cases of ALS.
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Affiliation(s)
- Niko Hensel
- 1 Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,2 Niedersachsen Network on Neuroinfectiology (N-RENNT), Hannover, Germany
| | - Peter Claus
- 1 Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,2 Niedersachsen Network on Neuroinfectiology (N-RENNT), Hannover, Germany.,3 Center for Systems Neuroscience (ZSN), Hannover, Germany
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41
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Härönen H, Zainul Z, Tu H, Naumenko N, Sormunen R, Miinalainen I, Shakirzyanova A, Oikarainen T, Abdullin A, Martin P, Santoleri S, Koistinaho J, Silman I, Giniatullin R, Fox MA, Heikkinen A, Pihlajaniemi T. Collagen XIII secures pre- and postsynaptic integrity of the neuromuscular synapse. Hum Mol Genet 2017; 26:2076-2090. [DOI: 10.1093/hmg/ddx101] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 03/10/2017] [Indexed: 01/01/2023] Open
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ALS-linked FUS exerts a gain of toxic function involving aberrant p38 MAPK activation. Sci Rep 2017; 7:115. [PMID: 28273913 PMCID: PMC5428330 DOI: 10.1038/s41598-017-00091-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 01/30/2017] [Indexed: 12/14/2022] Open
Abstract
Mutations in Fused in Sarcoma/Translocated in Liposarcoma (FUS) cause familial forms of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by progressive axonal degeneration mainly affecting motor neurons. Evidence from transgenic mouse models suggests mutant forms of FUS exert an unknown gain-of-toxic function in motor neurons, but mechanisms underlying this effect remain unknown. Towards this end, we studied the effect of wild type FUS (FUS WT) and three ALS-linked variants (G230C, R521G and R495X) on fast axonal transport (FAT), a cellular process critical for appropriate maintenance of axonal connectivity. All ALS-FUS variants impaired anterograde and retrograde FAT in squid axoplasm, whereas FUS WT had no effect. Misfolding of mutant FUS is implicated in this process, as the molecular chaperone Hsp110 mitigated these toxic effects. Interestingly, mutant FUS-induced impairment of FAT in squid axoplasm and of axonal outgrowth in mammalian primary motor neurons involved aberrant activation of the p38 MAPK pathway, as also reported for ALS-linked forms of Cu, Zn superoxide dismutase (SOD1). Accordingly, increased levels of active p38 MAPK were detected in post-mortem human ALS-FUS brain tissues. These data provide evidence for a novel gain-of-toxic function for ALS-linked FUS involving p38 MAPK activation.
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43
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Tu WY, Simpson JE, Highley JR, Heath PR. Spinal muscular atrophy: Factors that modulate motor neurone vulnerability. Neurobiol Dis 2017; 102:11-20. [PMID: 28161391 DOI: 10.1016/j.nbd.2017.01.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 01/10/2017] [Accepted: 01/31/2017] [Indexed: 01/07/2023] Open
Abstract
Spinal muscular atrophy (SMA), a leading genetic cause of infant death, is a neurodegenerative disease characterised by the selective loss of particular groups of motor neurones in the anterior horn of the spinal cord with concomitant muscle weakness. To date, no effective treatment is available, however, there are ongoing clinical trials are in place which promise much for the future. However, there remains an ongoing problem in trying to link a single gene loss to motor neurone degeneration. Fortunately, given successful disease models that have been established and intensive studies on SMN functions in the past ten years, we are fast approaching the stage of identifying the underlying mechanisms of SMA pathogenesis Here we discuss potential disease modifying factors on motor neurone vulnerability, in the belief that these factors give insight into the pathological mechanisms of SMA and therefore possible therapeutic targets.
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Affiliation(s)
- Wen-Yo Tu
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Julie E Simpson
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - J Robin Highley
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Paul R Heath
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK.
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Jones RA, Reich CD, Dissanayake KN, Kristmundsdottir F, Findlater GS, Ribchester RR, Simmen MW, Gillingwater TH. NMJ-morph reveals principal components of synaptic morphology influencing structure-function relationships at the neuromuscular junction. Open Biol 2016; 6:160240. [PMID: 27927794 PMCID: PMC5204123 DOI: 10.1098/rsob.160240] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/09/2016] [Indexed: 01/10/2023] Open
Abstract
The ability to form synapses is one of the fundamental properties required by the mammalian nervous system to generate network connectivity. Structural and functional diversity among synaptic populations is a key hallmark of network diversity, and yet we know comparatively little about the morphological principles that govern variability in the size, shape and strength of synapses. Using the mouse neuromuscular junction (NMJ) as an experimentally accessible model synapse, we report on the development of a robust, standardized methodology to facilitate comparative morphometric analysis of synapses ('NMJ-morph'). We used NMJ-morph to generate baseline morphological reference data for 21 separate pre- and post-synaptic variables from 2160 individual NMJs belonging to nine anatomically distinct populations of synapses, revealing systematic differences in NMJ morphology between defined synaptic populations. Principal components analysis revealed that overall NMJ size and the degree of synaptic fragmentation, alongside pre-synaptic axon diameter, were the most critical parameters in defining synaptic morphology. 'Average' synaptic morphology was remarkably conserved between comparable synapses from the left and right sides of the body. Systematic differences in synaptic morphology predicted corresponding differences in synaptic function that were supported by physiological recordings, confirming the robust relationship between synaptic size and strength.
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Affiliation(s)
- Ross A Jones
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Anatomy, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Caitlan D Reich
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Anatomy, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Kosala N Dissanayake
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Fanney Kristmundsdottir
- Anatomy, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Gordon S Findlater
- Anatomy, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Richard R Ribchester
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Martin W Simmen
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Centre for Integrative Physiology, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
- Anatomy, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Old Medical School, Teviot Place, Edinburgh EH8 9XD, UK
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45
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Ovsepian SV, O'Leary VB, Ntziachristos V, Dolly JO. Circumventing Brain Barriers: Nanovehicles for Retroaxonal Therapeutic Delivery. Trends Mol Med 2016; 22:983-993. [PMID: 27720365 DOI: 10.1016/j.molmed.2016.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 02/06/2023]
Abstract
In addition to safeguarding the central nervous system (CNS) from the vast majority of pathogens and toxins, transvascular barriers impose immense challenges to the delivery of beneficial cargo. A few toxins and neurotropic viruses capable of penetrating the brain have proved to be potentially valuable for neuron targeting and enhanced transfer of restorative medicine and therapeutic genes. Here we review molecular concepts and implications of the highly neurotropic tetanus toxin (TeTx) and botulinum neurotoxins (BoNTs) and their ability to infiltrate and migrate throughout neurons. We discuss recent applications of their detoxified variants as versatile nanovehicles for retroaxonal delivery of therapeutics to motor neurons and synapses. Continued advances in research on these remarkable agents in preclinical trials might facilitate their future use for medical benefit.
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Affiliation(s)
- Saak V Ovsepian
- Institute for Biological and Medical Imaging, Helmholtz Zentrum Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany; Munich School of Bioengineering, Technical University Munich, 81675 Munich, Germany; International Centre for Neurotherapeutics, Dublin City University, Dublin 9, Ireland.
| | - Valerie B O'Leary
- Institute of Radiation Biology, Helmholtz Zentrum Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Vasilis Ntziachristos
- Institute for Biological and Medical Imaging, Helmholtz Zentrum Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany; Munich School of Bioengineering, Technical University Munich, 81675 Munich, Germany
| | - J Oliver Dolly
- International Centre for Neurotherapeutics, Dublin City University, Dublin 9, Ireland
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Preservation of neuromuscular function in symptomatic SOD1-G93A mice by peripheral infusion of methylene blue. Exp Neurol 2016; 285:96-107. [PMID: 27567739 DOI: 10.1016/j.expneurol.2016.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 07/31/2016] [Accepted: 08/23/2016] [Indexed: 12/14/2022]
Abstract
In mutant superoxide dismutase 1 (SOD1) mouse models of familial amyotrophic lateral sclerosis (fALS) some of the earliest signs of morphological and functional damage occur in the motor nerve terminals that innervate fast limb muscles. This study tested whether localized peripheral application of a protective drug could effectively preserve neuromuscular junctions in late-stage disease. Methylene blue (MB), which has mitochondria-protective properties, was infused via an osmotic pump into the anterior muscle compartment of one hind limb of late pre- symptomatic SOD1-G93A mice for ≥3weeks. When mice reached end-stage disease, peak twitch and tetanic contractions evoked by stimulation of the muscle nerve were measured in two anterior compartment muscles (tibialis anterior [TA] and extensor digitorum longus [EDL], both predominantly fast muscles). With 400μM MB in the infusion reservoir, muscles on the MB-infused side exhibited on average a ~100% increase in nerve-evoked contractile force compared to muscles on the contralateral non-infused side (p<0.01 for both twitch and tetanus in EDL and TA). Pairwise comparisons of endplate innervation also revealed a beneficial effect of MB infusion, with an average of 65% of endplates innervated in infused EDL, compared to only 35% on the non-infused side (p<0.01). Results suggested that MB's protective effects required an extracellular [MB] of ~1μM, were initiated peripherally (no evidence of retrograde transport into the spinal cord), and involved MB's reduced form. Thus peripherally-initiated actions of MB can help preserve neuromuscular structure and function in SOD1-G93A mice, even at late stages of disease.
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Casas C, Manzano R, Vaz R, Osta R, Brites D. Synaptic Failure: Focus in an Integrative View of ALS. Brain Plast 2016; 1:159-175. [PMID: 29765840 PMCID: PMC5928542 DOI: 10.3233/bpl-140001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
From early description by Charcot, the classification of the Amyotrophic Lateral Sclerosis (ALS) is evolving from a subtype of Motor Neuron (MN) Disease to be considered rather a multi-systemic, non-cell autonomous and complex neurodegenerative disease. In the last decade, the huge amount of knowledge acquired has shed new insights on the pathological mechanisms underlying ALS from different perspectives. However, a whole vision on the multiple dysfunctional pathways is needed with the inclusion of information often excluded in other published revisions. We propose an integrative view of ALS pathology, although centered on the synaptic failure as a converging and crucial player to the etiology of the disease. Homeostasis of input and output synaptic activity of MNs has been proved to be severely and early disrupted and to definitively contribute to microcircuitry alterations at the spinal cord. Several cells play roles in synaptic communication across the MNs network system such as interneurons, astrocytes, microglia, Schwann and skeletal muscle cells. Microglia are described as highly dynamic surveying cells of the nervous system but also as determinant contributors to the synaptic plasticity linked to neuronal activity. Several signaling axis such as TNFα/TNFR1 and CX3CR1/CX3CL1 that characterize MN-microglia cross talk contribute to synaptic scaling and maintenance, have been found altered in ALS. The presence of dystrophic and atypical microglia in late stages of ALS, with a decline in their dynamic motility and phagocytic ability, together with less synaptic and neuronal contacts disrupts the MN-microglia dialogue, decreases homeostatic regulation of neuronal activity, perturbs “on/off” signals and accelerates disease progression associated to impaired synaptic function and regeneration. Other hotspot in the ALS affected network system is the unstable neuromuscular junction (NMJ) leading to distal axonal degeneration. Reduced neuromuscular spontaneous synaptic activity in ALS mice models was also suggested to account for the selective vulnerability of MNs and decreased regenerative capability. Synaptic destabilization may as well derive from increased release of molecules by muscle cells (e.g. NogoA) and by terminal Schwann cells (e.g. semaphorin 3A) conceivably causing nerve terminal retraction and denervation, as well as inhibition of re-connection to muscle fibers. Indeed, we have overviewed the alterations on the metabolic pathways and self-regenerative capacity presented in skeletal muscle cells that contribute to muscle wasting in ALS. Finally, a detailed footpath of pathologic changes on MNs and associated dysfunctional and synaptic alterations is provided. The oriented motivation in future ALS studies as outlined in the present article will help in fruitful novel achievements on the mechanisms involved and in developing more target-driven therapies that will bring new hope in halting or delaying disease progression in ALS patients.
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Affiliation(s)
- Caty Casas
- Group of Neuroplasticity and Regeneration, Institut de Neurociències and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Barcelona, Spain
| | - Raquel Manzano
- Laboratory of Genetic Biochemistry (LAGENBIO-I3A), Aragón Institute of Health Sciences, Universidad de Zaragoza, Zaragoza, Spain
| | - Rita Vaz
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa Lisbon, Portugal; Department of Biochemistry and Human Biology, Faculdade de Farmácia, Universidade de Lisboa Lisbon, Portugal
| | - Rosario Osta
- Laboratory of Genetic Biochemistry (LAGENBIO-I3A), Aragón Institute of Health Sciences, Universidad de Zaragoza, Zaragoza, Spain
| | - Dora Brites
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa Lisbon, Portugal; Department of Biochemistry and Human Biology, Faculdade de Farmácia, Universidade de Lisboa Lisbon, Portugal
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Neve A, Trüb J, Saxena S, Schümperli D. Central and peripheral defects in motor units of the diaphragm of spinal muscular atrophy mice. Mol Cell Neurosci 2016; 70:30-41. [PMID: 26621405 DOI: 10.1016/j.mcn.2015.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/30/2015] [Accepted: 11/23/2015] [Indexed: 01/08/2023] Open
Abstract
Spinal muscular atrophy (SMA) is characterized by motoneuron loss and muscle weakness. However, the structural and functional deficits that lead to the impairment of the neuromuscular system remain poorly defined. By electron microscopy, we previously found that neuromuscular junctions (NMJs) and muscle fibres of the diaphragm are among the earliest affected structures in the severe mouse SMA model. Because of certain anatomical features, i.e. its thinness and its innervation from the cervical segments of the spinal cord, the diaphragm is particularly suitable to characterize both central and peripheral events. Here we show by immunohistochemistry that, at postnatal day 3, the cervical motoneurons of SMA mice receive less stimulatory synaptic inputs. Moreover, their mitochondria become less elongated which might represent an early stage of degeneration. The NMJs of the diaphragm of SMA mice show a loss of synaptic vesicles and active zones. Moreover, the partly innervated endplates lack S100 positive perisynaptic Schwann cells (PSCs). We also demonstrate the feasibility of comparing the proteomic composition between diaphragm regions enriched and poor in NMJs. By this approach we have identified two proteins that are significantly upregulated only in the NMJ-specific regions of SMA mice. These are apoptosis inducing factor 1 (AIFM1), a mitochondrial flavoprotein that initiates apoptosis in a caspase-independent pathway, and four and a half Lim domain protein 1 (FHL1), a regulator of skeletal muscle mass that has been implicated in several myopathies.
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Affiliation(s)
- Anuja Neve
- Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Judith Trüb
- Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland
| | - Smita Saxena
- Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland
| | - Daniel Schümperli
- Institute of Cell Biology, University of Bern, 3012 Bern, Switzerland.
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Comley LH, Nijssen J, Frost-Nylen J, Hedlund E. Cross-disease comparison of amyotrophic lateral sclerosis and spinal muscular atrophy reveals conservation of selective vulnerability but differential neuromuscular junction pathology. J Comp Neurol 2015; 524:1424-42. [PMID: 26502195 PMCID: PMC5063101 DOI: 10.1002/cne.23917] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 10/16/2015] [Accepted: 10/22/2015] [Indexed: 12/13/2022]
Abstract
Neuromuscular junctions are primary pathological targets in the lethal motor neuron diseases spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS). Synaptic pathology and denervation of target muscle fibers has been reported prior to the appearance of clinical symptoms in mouse models of both diseases, suggesting that neuromuscular junctions are highly vulnerable from the very early stages, and are a key target for therapeutic intervention. Here we examined neuromuscular pathology longitudinally in three clinically relevant muscle groups in mouse models of ALS and SMA in order to assess their relative vulnerabilities. We show for the first time that neuromuscular junctions of the extraocular muscles (responsible for the control of eye movement) were resistant to degeneration in endstage SMA mice, as well as in late symptomatic ALS mice. Tongue muscle neuromuscular junctions were also spared in both animal models. Conversely, neuromuscular junctions of the lumbrical muscles of the hind‐paw were vulnerable in both SMA and ALS, with a loss of neuronal innervation and shrinkage of motor endplates in both diseases. Thus, the pattern of selective vulnerability was conserved across these two models of motor neuron disease. However, the first evidence of neuromuscular pathology occurred at different timepoints of disease progression, with much earlier evidence of presynaptic involvement in ALS, progressing to changes on the postsynaptic side. Conversely, in SMA changes appeared concomitantly at the neuromuscular junction, suggesting that mechanisms of neuromuscular disruption are distinct in these diseases. J. Comp. Neurol. 524:1424–1442, 2016. © 2015 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Laura H Comley
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jik Nijssen
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Gerevini S, Agosta F, Riva N, Spinelli EG, Pagani E, Caliendo G, Chaabane L, Copetti M, Quattrini A, Comi G, Falini A, Filippi M. MR Imaging of Brachial Plexus and Limb-Girdle Muscles in Patients with Amyotrophic Lateral Sclerosis. Radiology 2015; 279:553-61. [PMID: 26583760 DOI: 10.1148/radiol.2015150559] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To assess brachial plexus magnetic resonance (MR) imaging features and limb-girdle muscle abnormalities as signs of muscle denervation in patients with amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS This study was approved by the local ethical committees on human studies, and written informed consent was obtained from all subjects before enrollment. By using an optimized protocol of brachial plexus MR imaging, brachial plexus and limb-girdle muscle abnormalities were evaluated in 23 patients with ALS and clinical and neurophysiologically active involvement of the upper limbs and were compared with MR images in 12 age-matched healthy individuals. Nerve root and limb-girdle muscle abnormalities were visually evaluated by two experienced observers. A region of interest-based analysis was performed to measure nerve root volume and T2 signal intensity. Measures obtained at visual inspection were analyzed by using the Wald χ(2) test. Mean T2 signal intensity and volume values of the regions of interest were compared between groups by using a hierarchical linear model, accounting for the repeated measurement design. RESULTS The level of interrater agreement was very strong (κ = 0.77-1). T2 hyperintensity and volume alterations of C5, C6, and C7 nerve roots were observed in patients with ALS (P < .001 to .03). Increased T2 signal intensity of nerve roots was associated with faster disease progression (upper-limb Medical Research Council scale progression rate, r = 0.40; 95% confidence interval: 0.001, 0.73). Limb-girdle muscle alterations (ie, T2 signal intensity alteration, edema, atrophy) and fat infiltration also were found, in particular, in the supraspinatus muscle, showing more frequent T2 signal intensity alterations and edema (P = .01) relative to the subscapularis and infraspinatus muscles. CONCLUSION Increased T2 signal intensity and volume of brachial nerve roots do not exclude a diagnosis of ALS and suggest involvement of the peripheral nervous system in the ALS pathogenetic cascade. MR imaging of the peripheral nervous system and the limb-girdle muscle may be useful for monitoring the evolution of ALS and distinguishing patients with ALS from those with inflammatory neuropathy, respectively.
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Affiliation(s)
- Simonetta Gerevini
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Federica Agosta
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Nilo Riva
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Edoardo G Spinelli
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Elisabetta Pagani
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Giandomenico Caliendo
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Linda Chaabane
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Massimiliano Copetti
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Angelo Quattrini
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Giancarlo Comi
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Andrea Falini
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
| | - Massimo Filippi
- From the Department of Neuroradiology (S.G., G.Caliendo, A.F.), Neuroimaging Research Unit (F.A., E.G.S., E.P., M.F.), Department of Neurology (N.R., E.G.S., G.Comi, M.F.), and Neuropathology Unit (N.R., L.C., A.Q.), Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina 60, 20132 Milan, Italy; and Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy (M.C.)
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