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Mora S, Stuckert A, von Huth Friis R, Pietersz K, Noes-Holt G, Montañana-Rosell R, Wang H, Sørensen AT, Selvan R, Verhaagen J, Allodi I. Stabilization of V1 interneuron-motor neuron connectivity ameliorates motor phenotype in a mouse model of ALS. Nat Commun 2024; 15:4867. [PMID: 38849367 PMCID: PMC11161600 DOI: 10.1038/s41467-024-48925-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 05/17/2024] [Indexed: 06/09/2024] Open
Abstract
Loss of connectivity between spinal V1 inhibitory interneurons and motor neurons is found early in disease in the SOD1G93A mice. Such changes in premotor inputs can contribute to homeostatic imbalance of motor neurons. Here, we show that the Extended Synaptotagmin 1 (Esyt1) presynaptic organizer is downregulated in V1 interneurons. V1 restricted overexpression of Esyt1 rescues inhibitory synapses, increases motor neuron survival, and ameliorates motor phenotypes. Two gene therapy approaches overexpressing ESYT1 were investigated; one for local intraspinal delivery, and the other for systemic administration using an AAV-PHP.eB vector delivered intravenously. Improvement of motor functions is observed in both approaches, however systemic administration appears to significantly reduce onset of motor impairment in the SOD1G93A mice in absence of side effects. Altogether, we show that stabilization of V1 synapses by ESYT1 overexpression has the potential to improve motor functions in ALS, demonstrating that interneurons can be a target to attenuate ALS symptoms.
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Affiliation(s)
- Santiago Mora
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Anna Stuckert
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | | | - Kimberly Pietersz
- The Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Gith Noes-Holt
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | | | - Haoyu Wang
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | | | - Raghavendra Selvan
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Joost Verhaagen
- The Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Ilary Allodi
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark.
- School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.
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2
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Silva-Hucha S, Fernández de Sevilla ME, Humphreys KM, Benson FE, Franco JM, Pozo D, Pastor AM, Morcuende S. VEGF expression disparities in brainstem motor neurons of the SOD1 G93A ALS model: Correlations with neuronal vulnerability. Neurotherapeutics 2024; 21:e00340. [PMID: 38472048 PMCID: PMC11070718 DOI: 10.1016/j.neurot.2024.e00340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/08/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a rare neuromuscular disease characterized by severe muscle weakness mainly due to degeneration and death of motor neurons. A peculiarity of the neurodegenerative processes is the variable susceptibility among distinct neuronal populations, exemplified by the contrasting resilience of motor neurons innervating the ocular motor system and the more vulnerable facial and hypoglossal motor neurons. The crucial role of vascular endothelial growth factor (VEGF) as a neuroprotective factor in the nervous system is well-established since a deficit of VEGF has been related to motoneuronal degeneration. In this study, we investigated the survival of ocular, facial, and hypoglossal motor neurons utilizing the murine SOD1G93A ALS model at various stages of the disease. Our primary objective was to determine whether the survival of the different brainstem motor neurons was linked to disparate VEGF expression levels in resilient and susceptible motor neurons throughout neurodegeneration. Our findings revealed a selective loss of motor neurons exclusively within the vulnerable nuclei. Furthermore, a significantly higher level of VEGF was detected in the more resistant motor neurons, the extraocular ones. We also examined whether TDP-43 dynamics in the brainstem motor neuron of SOD mice was altered. Our data suggests that the increased VEGF levels observed in extraocular motor neurons may potentially underlie their resistance during the neurodegenerative processes in ALS in a TDP-43-independent manner. Our work might help to better understand the underlying mechanisms of selective vulnerability of motor neurons in ALS.
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Affiliation(s)
- Silvia Silva-Hucha
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain; Cell and Developmental Biology, University College London, Medawar Building, Gower Street, London WC1E 6BT, UK
| | | | - Kirsty M Humphreys
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster LA1 4YQ, UK
| | - Fiona E Benson
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster LA1 4YQ, UK
| | - Jaime M Franco
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucía-Universidad Pablo de Olavide-Universidad de Sevilla-CSIC, 41092, Seville, Spain
| | - David Pozo
- Andalusian Center of Molecular Biology and Regenerative Medicine-CABIMER, Junta de Andalucía-Universidad Pablo de Olavide-Universidad de Sevilla-CSIC, 41092, Seville, Spain; Department of Medical Biochemistry, Molecular Biology and Immunology, Universidad de Sevilla Medical School, 41009 Seville, Spain
| | - Angel M Pastor
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
| | - Sara Morcuende
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain.
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3
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Jagaraj CJ, Shadfar S, Kashani SA, Saravanabavan S, Farzana F, Atkin JD. Molecular hallmarks of ageing in amyotrophic lateral sclerosis. Cell Mol Life Sci 2024; 81:111. [PMID: 38430277 PMCID: PMC10908642 DOI: 10.1007/s00018-024-05164-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/21/2024] [Accepted: 02/06/2024] [Indexed: 03/03/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal, severely debilitating and rapidly progressing disorder affecting motor neurons in the brain, brainstem, and spinal cord. Unfortunately, there are few effective treatments, thus there remains a critical need to find novel interventions that can mitigate against its effects. Whilst the aetiology of ALS remains unclear, ageing is the major risk factor. Ageing is a slowly progressive process marked by functional decline of an organism over its lifespan. However, it remains unclear how ageing promotes the risk of ALS. At the molecular and cellular level there are specific hallmarks characteristic of normal ageing. These hallmarks are highly inter-related and overlap significantly with each other. Moreover, whilst ageing is a normal process, there are striking similarities at the molecular level between these factors and neurodegeneration in ALS. Nine ageing hallmarks were originally proposed: genomic instability, loss of telomeres, senescence, epigenetic modifications, dysregulated nutrient sensing, loss of proteostasis, mitochondrial dysfunction, stem cell exhaustion, and altered inter-cellular communication. However, these were recently (2023) expanded to include dysregulation of autophagy, inflammation and dysbiosis. Hence, given the latest updates to these hallmarks, and their close association to disease processes in ALS, a new examination of their relationship to pathophysiology is warranted. In this review, we describe possible mechanisms by which normal ageing impacts on neurodegenerative mechanisms implicated in ALS, and new therapeutic interventions that may arise from this.
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Affiliation(s)
- Cyril Jones Jagaraj
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia
| | - Sina Shadfar
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia
| | - Sara Assar Kashani
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia
| | - Sayanthooran Saravanabavan
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia
| | - Fabiha Farzana
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia
| | - Julie D Atkin
- MND Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, 75 Talavera Road, Sydney, NSW, 2109, Australia.
- La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Melbourne, VIC, 3086, Australia.
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4
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Ojeda J, Vergara M, Ávila A, Henríquez JP, Fehlings M, Vidal PM. Impaired communication at the neuromotor axis during Degenerative Cervical Myelopathy. Front Cell Neurosci 2024; 17:1316432. [PMID: 38269114 PMCID: PMC10806149 DOI: 10.3389/fncel.2023.1316432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 12/18/2023] [Indexed: 01/26/2024] Open
Abstract
Degenerative Cervical Myelopathy (DCM) is a progressive neurological condition characterized by structural alterations in the cervical spine, resulting in compression of the spinal cord. While clinical manifestations of DCM are well-documented, numerous unanswered questions persist at the molecular and cellular levels. In this study, we sought to investigate the neuromotor axis during DCM. We use a clinically relevant mouse model, where after 3 months of DCM induction, the sensorimotor tests revealed a significant reduction in both locomotor activity and muscle strength compared to the control group. Immunohistochemical analyses showed alterations in the gross anatomy of the cervical spinal cord segment after DCM. These changes were concomitant with the loss of motoneurons and a decrease in the number of excitatory synaptic inputs within the spinal cord. Additionally, the DCM group exhibited a reduction in the endplate surface, which correlated with diminished presynaptic axon endings in the supraspinous muscles. Furthermore, the biceps brachii (BB) muscle exhibited signs of atrophy and impaired regenerative capacity, which inversely correlated with the transversal area of remnants of muscle fibers. Additionally, metabolic assessments in BB muscle indicated an increased proportion of oxidative skeletal muscle fibers. In line with the link between neuromotor disorders and gut alterations, DCM mice displayed smaller mucin granules in the mucosa layer without damage to the epithelial barrier in the colon. Notably, a shift in the abundance of microbiota phylum profiles reveals an elevated Firmicutes-to-Bacteroidetes ratio-a consistent hallmark of dysbiosis that correlates with alterations in gut microbiota-derived metabolites. Additionally, treatment with short-chain fatty acids stimulated the differentiation of the motoneuron-like NSC34 cell line. These findings shed light on the multifaceted nature of DCM, resembling a synaptopathy that disrupts cellular communication within the neuromotor axis while concurrently exerting influence on other systems. Notably, the colon emerges as a focal point, experiencing substantial perturbations in both mucosal barrier integrity and the delicate balance of intestinal microbiota.
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Affiliation(s)
- Jorge Ojeda
- Neuroimmunology and Regeneration of the Central Nervous System Unit, Biomedical Science Research Laboratory, Basic Sciences Department, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Mayra Vergara
- Neuroimmunology and Regeneration of the Central Nervous System Unit, Biomedical Science Research Laboratory, Basic Sciences Department, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Ariel Ávila
- Developmental Neurobiology Unit, Biomedical Science Research Laboratory, Basic Sciences Department, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Juan Pablo Henríquez
- Neuromuscular Studies Lab (NeSt Lab), Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Michael Fehlings
- Department of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Spinal Program, University Health Network, Toronto Western Hospital, Toronto, ON, Canada
| | - Pia M. Vidal
- Neuroimmunology and Regeneration of the Central Nervous System Unit, Biomedical Science Research Laboratory, Basic Sciences Department, Faculty of Medicine, Universidad Católica de la Santísima Concepción, Concepción, Chile
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5
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Ovsepian SV, O'Leary VB, Martinez S. Selective vulnerability of motor neuron types and functional groups to degeneration in amyotrophic lateral sclerosis: review of the neurobiological mechanisms and functional correlates. Brain Struct Funct 2024; 229:1-14. [PMID: 37999738 PMCID: PMC10827929 DOI: 10.1007/s00429-023-02728-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition characterised by a progressive loss of motor neurons controlling voluntary muscle activity. The disease manifests through a variety of motor dysfunctions related to the extent of damage and loss of neurons at different anatomical locations. Despite extensive research, it remains unclear why some motor neurons are especially susceptible to the disease, while others are affected less or even spared. In this article, we review the neurobiological mechanisms, neurochemical profiles, and morpho-functional characteristics of various motor neuron groups and types of motor units implicated in their differential exposure to degeneration. We discuss specific cell-autonomous (intrinsic) and extrinsic factors influencing the vulnerability gradient of motor units and motor neuron types to ALS, with their impact on disease manifestation, course, and prognosis, as revealed in preclinical and clinical studies. We consider the outstanding challenges and emerging opportunities for interpreting the phenotypic and mechanistic variability of the disease to identify targets for clinical interventions.
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Affiliation(s)
- Saak V Ovsepian
- Faculty of Engineering and Science, University of Greenwich London, Chatham Maritime, Kent, ME4 4TB, UK.
| | - Valerie B O'Leary
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská 87, 10000, Prague, Czech Republic
| | - Salvador Martinez
- Instituto de Neurociencias UMH-CSIC, Avda. Ramon y Cajal, 03550, San Juan de Alicante, Spain.
- Center of Biomedical Network Research on Mental Health (CIBERSAM), ISCIII, Madrid, Spain.
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6
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Veshchitskii A, Merkulyeva N. Calcium-binding protein parvalbumin in the spinal cord and dorsal root ganglia. Neurochem Int 2023; 171:105634. [PMID: 37967669 DOI: 10.1016/j.neuint.2023.105634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 09/20/2023] [Accepted: 10/26/2023] [Indexed: 11/17/2023]
Abstract
Parvalbumin is one of the calcium-binding proteins. In the spinal cord, it is mainly expressed in inhibitory neurons; in the dorsal root ganglia, it is expressed in proprioceptive neurons. In contrast to in the brain, weak systematization of parvalbumin-expressing neurons occurs in the spinal cord. The aim of this paper is to provide a systematic review of parvalbumin-expressing neuronal populations throughout the spinal cord and the dorsal root ganglia of mammals, regarding their mapping, co-expression with some functional markers. The data reviewed are mostly concerning rodentia species because they are predominantly presented in literature.
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Affiliation(s)
- Aleksandr Veshchitskii
- Neuromorphology Lab, Pavlov Institute of Physiology Russian Academy of Sciences, Saint Petersburg, Russia
| | - Natalia Merkulyeva
- Neuromorphology Lab, Pavlov Institute of Physiology Russian Academy of Sciences, Saint Petersburg, Russia.
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7
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Kandeel M, Morsy MA, Alkhodair KM, Alhojaily S. Mesenchymal Stem Cell-Derived Extracellular Vesicles: An Emerging Diagnostic and Therapeutic Biomolecules for Neurodegenerative Disabilities. Biomolecules 2023; 13:1250. [PMID: 37627315 PMCID: PMC10452295 DOI: 10.3390/biom13081250] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Mesenchymal stem cells (MSCs) are a type of versatile adult stem cells present in various organs. These cells give rise to extracellular vesicles (EVs) containing a diverse array of biologically active elements, making them a promising approach for therapeutics and diagnostics. This article examines the potential therapeutic applications of MSC-derived EVs in addressing neurodegenerative disorders such as Alzheimer's disease (AD), multiple sclerosis (MS), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). Furthermore, the present state-of-the-art for MSC-EV-based therapy in AD, HD, PD, ALS, and MS is discussed. Significant progress has been made in understanding the etiology and potential treatments for a range of neurodegenerative diseases (NDs) over the last few decades. The contents of EVs are carried across cells for intercellular contact, which often results in the control of the recipient cell's homeostasis. Since EVs represent the therapeutically beneficial cargo of parent cells and are devoid of many ethical problems connected with cell-based treatments, they offer a viable cell-free therapy alternative for tissue regeneration and repair. Developing innovative EV-dependent medicines has proven difficult due to the lack of standardized procedures in EV extraction processes as well as their pharmacological characteristics and mechanisms of action. However, recent biotechnology and engineering research has greatly enhanced the content and applicability of MSC-EVs.
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Affiliation(s)
- Mahmoud Kandeel
- Department of Biomedical Sciences, College of Veterinary Medicine, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
- Department of Pharmacology, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafrelsheikh 33516, Egypt
| | - Mohamed A. Morsy
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
- Department of Pharmacology, Faculty of Medicine, Minia University, El-Minia 61511, Egypt
| | - Khalid M. Alkhodair
- Department of Anatomy, College of Veterinary Medicine, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
| | - Sameer Alhojaily
- Department of Biomedical Sciences, College of Veterinary Medicine, King Faisal University, Al-Ahsa 31982, Saudi Arabia;
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8
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Onda-Ohto A, Hasegawa-Ogawa M, Matsuno H, Shiraishi T, Bono K, Hiraki H, Kanegae Y, Iguchi Y, Okano HJ. Specific vulnerability of iPSC-derived motor neurons with TDP-43 gene mutation to oxidative stress. Mol Brain 2023; 16:62. [PMID: 37496071 PMCID: PMC10369818 DOI: 10.1186/s13041-023-01050-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/18/2023] [Indexed: 07/28/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a disease that affects motor neurons and has a poor prognosis. We focused on TAR DNA-binding protein 43 kDa (TDP-43), which is a common component of neuronal inclusions in many ALS patients. To analyze the contribution of TDP-43 mutations to ALS in human cells, we first introduced TDP-43 mutations into healthy human iPSCs using CRISPR/Cas9 gene editing technology, induced the differentiation of these cells into motor and sensory neurons, and analyzed factors that are assumed to be altered in or associated with ALS (cell morphology, TDP-43 localization and aggregate formation, cell death, TDP-43 splicing function, etc.). We aimed to clarify the pathological alterations caused solely by TDP-43 mutation, i.e., the changes in human iPSC-derived neurons with TDP-43 mutation compared with those with the same genetic background except TDP-43 mutation. Oxidative stress induced by hydrogen peroxide administration caused the death of TDP-43 mutant-expressing motor neurons but not in sensory neurons, indicating the specific vulnerability of human iPSC-derived motor neurons with TDP-43 mutation to oxidative stress. In our model, we observed aggregate formation in a small fraction of TDP-43 mutant-expressing motor neurons, suggesting that aggregate formation seems to be related to ALS pathology but not the direct cause of cell death. This study provides basic knowledge for elucidating the pathogenesis of ALS and developing treatments for the disease.
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Affiliation(s)
- Asako Onda-Ohto
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Minami Hasegawa-Ogawa
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Hiromasa Matsuno
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Tomotaka Shiraishi
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Keiko Bono
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Hiromi Hiraki
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Yumi Kanegae
- Core Research Facilities, Research Center for Medical Sciences, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Yasuyuki Iguchi
- Department of Neurology, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan
| | - Hirotaka James Okano
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo, 105-8461, Japan.
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9
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Venugopal S, Ghulam-Jhelani Z, Ahn IS, Yang X, Wiedau M, Simmons D, Chandler SH. Early deficits in GABA inhibition parallels an increase in L-type Ca 2+ currents in the jaw motor neurons of SOD1 G93A mouse model for ALS. Neurobiol Dis 2023; 177:105992. [PMID: 36623607 DOI: 10.1016/j.nbd.2023.105992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 12/21/2022] [Accepted: 01/05/2023] [Indexed: 01/09/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) involves protracted pre-symptomatic periods of abnormal motor neuron (MN) excitability occurring in parallel with central and peripheral synaptic perturbations. Focusing on inhibitory control of MNs, we first compared longitudinal changes in pre-synaptic terminal proteins for GABA and glycine neurotransmitters around the soma of retrogradely identified trigeminal jaw closer (JC) MNs and ChAT-labeled midbrain extraocular (EO) MNs in the SOD1G93A mouse model for ALS. Fluorescence immunocytochemistry and confocal imaging were used to quantify GAD67 and GlyT2 synaptic bouton density (SBD) around MN soma at pre-symptomatic ages ∼P12 (postnatal), ∼P50 (adult) and near disease end-stage (∼P135) in SOD1G93A mice and age-matched wild-type (WT) controls. We noted reduced GAD67 innervation in the SOD1G93A trigeminal jaw closer MNs around P12, relative to age-matched WT and no significant difference around P50 and P135. In contrast, both GAD67 and GlyT2 innervation were elevated in the SOD1G93A EO MNs at the pre-symptomatic time points. Considering trigeminal MNs are vulnerable in ALS while EO MNs are spared, we suggest that upregulation of inhibition in the latter might be compensatory. Notable contrast also existed in the innate co-expression patterns of GAD67 and GlyT2 with higher mutual information (co-dependency) in EO MNs compared to JC in both SOD1G93A and WT mice, especially at adult stages (P50 and P135). Around P12 when GAD67 terminals expression was low in the mutant, we further tested for persistent GABA inhibition in those MNs using in vitro patch-clamp electrophysiology. Our results show that SOD1G93A JC MNs have reduced persistent GABA inhibition, relative to WT. Pharmacological blocking of an underlying tonically active GABA conductance using the GABA-α5 subunit inverse agonist, L-655-708, disinhibited WT JC MNs and lowered their recruitment threshold, suggesting its role in the control of intrinsic MN excitability. Quantitative RT-PCR in laser dissected JC MNs further supported a reduction in GABA-α5 subunit mRNA expression in the mutant. In light of our previous report that JC MNs forming putative fast motor units have lower input threshold in the SOD1G93A mice, we suggest that our present result on reduced GABA-α5 tonic inhibition provides for a mechanism contributing to such imbalance. In parallel with reduced GABA inhibition, we noted an increase in voltage-gated L-type Ca2+ currents in the mutant JC MNs around P12. Together these results support that, early modifications in intrinsic properties of vulnerable MNs could be an adaptive response to counter synaptic deficits.
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Affiliation(s)
- Sharmila Venugopal
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Neurology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| | - Zohal Ghulam-Jhelani
- Undergraduate Interdepartmental Program for Neuroscience, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - In Sook Ahn
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Xia Yang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Martina Wiedau
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Dwayne Simmons
- Department of Biology, Baylor University, Waco, TX 76798, USA
| | - Scott H Chandler
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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10
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Maugeri G, D'Amico AG, D'Agata V. Emerging Roles of the Neurotrophic Peptides IGF-1 and PACAP in Amyotrophic Lateral Sclerosis. Curr Protein Pept Sci 2022; 23:571-573. [PMID: 35929635 DOI: 10.2174/1389203723666220805123251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/22/2022]
Affiliation(s)
- Grazia Maugeri
- Department of Biomedical and Biotechnological Sciences, Section of Anatomy, Histology and Movement Sciences, University of Catania, 95100 Catania, Italy
| | | | - Velia D'Agata
- Department of Biomedical and Biotechnological Sciences, Section of Anatomy, Histology and Movement Sciences, University of Catania, 95100 Catania, Italy
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11
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The Cell Autonomous and Non-Cell Autonomous Aspects of Neuronal Vulnerability and Resilience in Amyotrophic Lateral Sclerosis. BIOLOGY 2022; 11:biology11081191. [PMID: 36009818 PMCID: PMC9405388 DOI: 10.3390/biology11081191] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/14/2022] [Accepted: 07/30/2022] [Indexed: 11/17/2022]
Abstract
Simple Summary Amyotrophic lateral sclerosis (ALS) is a fatal disease characterized by a progressive paralysis due to the loss of particular neurons in our nervous system called motor neurons, that exert voluntary control of all our skeletal muscles. It is not entirely understood why motor neurons are particularly vulnerable in ALS, neither is it completely clear why certain groups of motor neurons, including those that regulate eye movement, are rather resilient to this disease. However, both vulnerability and resilience to ALS likely reflect cell intrinsic properties of different motor neuron subpopulations as well as non-cell autonomous events regulated by surrounding cell types. In this review we dissect the particular properties of different motor neuron types and their responses to disease that may underlie their respective vulnerabilities and resilience. Disease progression in ALS involves multiple cell types that are closely connected to motor neurons and we here also discuss their contributions to the differential vulnerability of motor neurons. Abstract Amyotrophic lateral sclerosis (ALS) is defined by the loss of upper motor neurons (MNs) that project from the cerebral cortex to the brain stem and spinal cord and of lower MNs in the brain stem and spinal cord which innervate skeletal muscles, leading to spasticity, muscle atrophy, and paralysis. ALS involves several disease stages, and multiple cell types show dysfunction and play important roles during distinct phases of disease initiation and progression, subsequently leading to selective MN loss. Why MNs are particularly vulnerable in this lethal disease is still not entirely clear. Neither is it fully understood why certain MNs are more resilient to degeneration in ALS than others. Brain stem MNs of cranial nerves III, IV, and VI, which innervate our eye muscles, are highly resistant and persist until the end-stage of the disease, enabling paralyzed patients to communicate through ocular tracking devices. MNs of the Onuf’s nucleus in the sacral spinal cord, that innervate sphincter muscles and control urogenital functions, are also spared throughout the disease. There is also a differential vulnerability among MNs that are intermingled throughout the spinal cord, that directly relate to their physiological properties. Here, fast-twitch fatigable (FF) MNs, which innervate type IIb muscle fibers, are affected early, before onset of clinical symptoms, while slow-twitch (S) MNs, that innervate type I muscle fibers, remain longer throughout the disease progression. The resilience of particular MN subpopulations has been attributed to intrinsic determinants and multiple studies have demonstrated their unique gene regulation and protein content in health and in response to disease. Identified factors within resilient MNs have been utilized to protect more vulnerable cells. Selective vulnerability may also, in part, be driven by non-cell autonomous processes and the unique surroundings and constantly changing environment close to particular MN groups. In this article, we review in detail the cell intrinsic properties of resilient and vulnerable MN groups, as well as multiple additional cell types involved in disease initiation and progression and explain how these may contribute to the selective MN resilience and vulnerability in ALS.
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Epigenome-wide DNA methylation study of whole blood in patients with sporadic amyotrophic lateral sclerosis. Chin Med J (Engl) 2022; 135:1466-1473. [PMID: 35853630 PMCID: PMC9481424 DOI: 10.1097/cm9.0000000000002090] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background: Epigenetics, and especially DNA methylation, contributes to the pathogenesis of sporadic amyotrophic lateral sclerosis (SALS). This study aimed to investigate the role of DNA methylation in SALS using whole blood of SALS patients. Methods: In total, 32 SALS patients and 32 healthy controls were enrolled in this study. DNA was isolated from whole blood collected from the participants. DNA methylation profiles were generated using Infinium MethylationEPIC BeadChip. Results: We identified 34 significant differentially methylated positions (DMPs) in whole blood from SALS patients, compared with the healthy controls. Of these DMPs, five were hypermethylated and 29 were hypomethylated; they corresponded to 13 genes. For the DMPs, ATAD3B and BLK were hypermethylated, whereas DDO, IQCE, ABCB1, DNAH9, FIGN, NRP1, TMEM87B, CCSAP, ST6GALNAC5, MYOM2, and RUSC1-AS1 were hypomethylated. We also identified 12 differentially methylated regions (DMRs), related to 12 genes (NWD1, LDHD, CIS, IQCE, TNF, PDE1C, LGALS1, CSNK1E, LRRC23, ENO2, ELOVL2, and ELOVL2-AS1). According to data from the Kyoto Encyclopedia of Genes and Genomes database, DNAH9 and TNF are involved in the amyotrophic lateral sclerosis (ALS) pathway. Correlation analysis between clinical features and DNA methylation profiling indicated that the methylation level of ELOVL2 and ARID1B was positively associated with the age of onset (r = 0.86, adjust P = 0.001) and disease duration (r = 0.83, adjust P = 0.01), respectively. Conclusions: We found aberrant methylation in DMP- and DMR-related genes, implying that many epigenetic alterations, such as the hypomethylation of DNAH9 and TNF, play important roles in ALS etiology. These findings can be helpful for developing new therapeutic interventions.
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Hur SK, Hunter M, Dominique MA, Farag M, Cotton-Samuel D, Khan T, Trojanowski JQ, Spiller KJ, Lee VMY. Slow motor neurons resist pathological TDP-43 and mediate motor recovery in the rNLS8 model of amyotrophic lateral sclerosis. Acta Neuropathol Commun 2022; 10:75. [PMID: 35568882 PMCID: PMC9107273 DOI: 10.1186/s40478-022-01373-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 04/25/2022] [Indexed: 01/22/2023] Open
Abstract
In the intermediate stages of amyotrophic lateral sclerosis (ALS), surviving motor neurons (MNs) that show intrinsic resistance to TDP-43 proteinopathy can partially compensate for the loss of their more disease-susceptible counterparts. Elucidating the mechanisms of this compensation may reveal approaches for attenuating motor impairment in ALS patients. In the rNLS8 mouse model of ALS-like pathology driven by doxycycline-regulated neuronal expression of human TDP-43 lacking a nuclear localization signal (hTDP-43ΔNLS), slow MNs are more resistant to disease than fast-fatigable (FF) MNs and can mediate recovery following transgene suppression. In the present study, we used a viral tracing strategy to show that these disease-resistant slow MNs sprout to reinnervate motor endplates of adjacent muscle fibers vacated by degenerated FF MNs. Moreover, we found that neuromuscular junctions within fast-twitch skeletal muscle (tibialis anterior, TA) reinnervated by SK3-positive slow MNs acquire resistance to axonal dieback when challenged with a second course of hTDP-43ΔNLS pathology. The selective resistance of reinnervated neuromuscular junctions was specifically induced by the unique pattern of reinnervation following TDP-43-induced neurodegeneration, as recovery from unilateral sciatic nerve crush did not produce motor units resistant to subsequent hTDP-43ΔNLS. Using cross-reinnervation and self-reinnervation surgery in which motor axons are disconnected from their target muscle and reconnected to a new muscle, we show that FF MNs remain hTDP-43ΔNLS-susceptible and slow MNs remain resistant, regardless of which muscle fibers they control. Collectively, these findings demonstrate that MN identity dictates the susceptibility of neuromuscular junctions to TDP-43 pathology and slow MNs can drive recovery of motor systems due to their remarkable resilience to TDP-43-driven degeneration. This study highlights a potential pathway for regaining motor function with ALS pathology in the advent of therapies that halt the underlying neurodegenerative process.
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Affiliation(s)
- Seong Kwon Hur
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Mandana Hunter
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Myrna A. Dominique
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Madona Farag
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Dejania Cotton-Samuel
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Tahiyana Khan
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - John Q. Trojanowski
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA ,grid.25879.310000 0004 1936 8972Alzheimer’s Disease Research Center, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
| | - Krista J. Spiller
- grid.497530.c0000 0004 0389 4927Janssen Research and Development, Neuroscience Therapeutic Area, 1400 McKean Rd, Spring House, PA 19002 USA
| | - Virginia M.-Y. Lee
- grid.25879.310000 0004 1936 8972Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Maloney Building, 3rd Floor, 3600 Spruce Street, Philadelphia, PA 19104-2676 USA ,grid.25879.310000 0004 1936 8972Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA ,grid.25879.310000 0004 1936 8972Alzheimer’s Disease Research Center, Perelman School of Medicine, University of Pennsylvania, 3400 Civic Center Blvd, Philadelphia, PA 19104 USA
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Broadhead MJ, Bonthron C, Waddington J, Smith WV, Lopez MF, Burley S, Valli J, Zhu F, Komiyama NH, Smith C, Grant SGN, Miles GB. Selective vulnerability of tripartite synapses in amyotrophic lateral sclerosis. Acta Neuropathol 2022; 143:471-486. [PMID: 35305541 PMCID: PMC8960590 DOI: 10.1007/s00401-022-02412-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/23/2022] [Accepted: 03/09/2022] [Indexed: 12/12/2022]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disorder. Separate lines of evidence suggest that synapses and astrocytes play a role in the pathological mechanisms underlying ALS. Given that astrocytes make specialised contacts with some synapses, called tripartite synapses, we hypothesise that tripartite synapses could act as the fulcrum of disease in ALS. To test this hypothesis, we have performed an extensive microscopy-based investigation of synapses and tripartite synapses in the spinal cord of ALS model mice and post-mortem human tissue from ALS cases. We reveal widescale synaptic changes at the early symptomatic stages of the SOD1G93a mouse model. Super-resolution microscopy reveals that large complex postsynaptic structures are lost in ALS mice. Most surprisingly, tripartite synapses are selectively lost, while non-tripartite synapses remain in equal number to healthy controls. Finally, we also observe a similar selective loss of tripartite synapses in human post-mortem ALS spinal cords. From these data we conclude that tripartite synaptopathy is a key hallmark of ALS.
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Stathmins and Motor Neuron Diseases: Pathophysiology and Therapeutic Targets. Biomedicines 2022; 10:biomedicines10030711. [PMID: 35327513 PMCID: PMC8945549 DOI: 10.3390/biomedicines10030711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 02/04/2023] Open
Abstract
Motor neuron diseases (MNDs) are a group of fatal, neurodegenerative disorders with different etiology, clinical course and presentation, caused by the loss of upper and lower motor neurons (MNs). MNs are highly specialized cells equipped with long, axonal processes; axonal defects are some of the main players underlying the pathogenesis of these disorders. Microtubules are key components of the neuronal cytoskeleton characterized by dynamic instability, switching between rapid polymerization and shrinkage. Proteins of the stathmin family affect microtubule dynamics regulating the assembly and the dismantling of tubulin. Stathmin-2 (STMN2) is one of the most abundantly expressed genes in MNs. Following axonal injury, STMN2 expression is upregulated, and the protein is transported toward the growth cones of regenerating axons. STMN2 has a critical role in axonal maintenance, and its dysregulation plays an important role in neurodegenerative processes. Stathmin-1 (STMN1) is a ubiquitous protein that is highly expressed during the development of the nervous system, and its phosphorylation controls microtubule dynamics. In the present review, we summarize what is currently known about the involvement of stathmin alterations in MNDs and the potential therapeutic effect of their modulation, with a specific focus on the most common forms of MND, amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA).
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Kim D, Kim S, Sung A, Patel N, Wong N, Conboy MJ, Conboy IM. Autologous treatment for ALS with implication for broad neuroprotection. Transl Neurodegener 2022; 11:16. [PMID: 35272709 PMCID: PMC8915496 DOI: 10.1186/s40035-022-00290-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 02/18/2022] [Indexed: 01/20/2023] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is characterized by a progressive loss of motor neurons (MNs), leading to paralysis, respiratory failure and death within 2–5 years of diagnosis. The exact mechanisms of sporadic ALS, which comprises 90% of all cases, remain unknown. In familial ALS, mutations in superoxide dismutase (SOD1) cause 10% of cases. Methods ALS patient-derived human-induced pluripotent stem cells (ALS hiPSCs, harboring the SOD1AV4 mutation), were differentiated to MNs (ALS-MNs). The neuroprotective effects of conditioned medium (CM) of hESCs (H9), wt hiPSCs (WTC-11) and the ALS iPSCs, on MN apoptosis and viability, formation and maintenance of neurites, mitochondrial activity and expression of inflammatory genes, were examined. For in vivo studies, 200 μl of CM from the ALS iPSCs (CS07 and CS053) was injected subcutaneously into the ALS model mice (transgenic for the human SOD1G93A mutation). Animal agility and strength, muscle innervation and mass, neurological score, onset of paralysis and lifespan of the ALS mice were assayed. After observing significant disease-modifying effects, the CM was characterized biochemically by fractionation, comparative proteomics, and epigenetic screens for the dependence on pluripotency. CM of fibroblasts that were differentiated from the wt hiPSCs lacked any neuroprotective activity and was used as a negative control throughout the studies. Results The secretome of PSCs including the ALS patient iPSCs was neuroprotective in the H2O2 model. In the model with pathogenic SOD1 mutation, ALS iPSC-CM attenuated all examined hallmarks of ALS pathology, rescued human ALS-MNs from denervation and death, restored mitochondrial health, and reduced the expression of inflammatory genes. The ALS iPSC-CM also improved neuro-muscular health and function, and delayed paralysis and morbidity in ALS mice. Compared side by side, cyclosporine (CsA), a mitochondrial membrane blocker that prevents the leakage of mitochondrial DNA, failed to avert the death of ALS-MNs, although CsA and ALS iPSC-CM equally stabilized MN mitochondria and attenuated inflammatory genes. Biochemical characterization, comparative proteomics, and epigenetic screen all suggested that it was the interactome of several key proteins from different fractions of PSC-CM that delivered the multifaceted neuroprotection. Conclusions This work introduces and mechanistically characterizes a new biologic for treating ALS and other complex neurodegenerative diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s40035-022-00290-5.
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Affiliation(s)
- Daehwan Kim
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Subin Kim
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Ashley Sung
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Neetika Patel
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Nathan Wong
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Michael J Conboy
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA
| | - Irina M Conboy
- Department of Bioengineering and QB3 Institute, University of California, Berkeley, CA, 94720, USA.
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McLeod VM, Chiam MDF, Perera ND, Lau CL, Boon WC, Turner BJ. Mapping Motor Neuron Vulnerability in the Neuraxis of Male SOD1 G93A Mice Reveals Widespread Loss of Androgen Receptor Occurring Early in Spinal Motor Neurons. Front Endocrinol (Lausanne) 2022; 13:808479. [PMID: 35273564 PMCID: PMC8902593 DOI: 10.3389/fendo.2022.808479] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/19/2022] [Indexed: 12/11/2022] Open
Abstract
Sex steroid hormones have been implicated as disease modifiers in the neurodegenerative disorder amyotrophic lateral sclerosis (ALS). Androgens, signalling via the androgen receptor (AR), predominate in males, and have widespread actions in the periphery and the central nervous system (CNS). AR translocates to the cell nucleus when activated upon binding androgens, whereby it regulates transcription of target genes via the classical genomic signalling pathway. We previously reported that AR protein is decreased in the lumbar spinal cord tissue of symptomatic male SOD1G93A mice. Here, we further explored the changes in AR within motor neurons (MN) of the CNS, assessing their nuclear AR content and propensity to degenerate by endstage disease in male SOD1G93A mice. We observed that almost all motor neuron populations had undergone significant loss in nuclear AR in SOD1G93A mice. Interestingly, loss of nuclear AR was evident in lumbar spinal MNs as early as the pre-symptomatic age of 60 days. Several MN populations with high AR content were identified which did not degenerate in SOD1G93A mice. These included the brainstem ambiguus and vagus nuclei, and the sexually dimorphic spinal MNs: cremaster, dorsolateral nucleus (DLN) and spinal nucleus of bulbocavernosus (SNB). In conclusion, we demonstrate that AR loss directly associates with MN vulnerability and disease progression in the SOD1G93A mouse model of ALS.
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Affiliation(s)
- Victoria M. McLeod
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Mathew D. F. Chiam
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Nirma D. Perera
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Chew L. Lau
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Wah Chin Boon
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Bradley J. Turner
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
- Perron Institute for Neurological and Translational Science, Queen Elizabeth Medical Centre, Nedlands, WA, Australia
- *Correspondence: Bradley J. Turner,
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Zhao J, Stevens CH, Boyd AW, Ooi L, Bartlett PF. Role of EphA4 in Mediating Motor Neuron Death in MND. Int J Mol Sci 2021; 22:9430. [PMID: 34502339 PMCID: PMC8430883 DOI: 10.3390/ijms22179430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/26/2021] [Accepted: 08/26/2021] [Indexed: 11/26/2022] Open
Abstract
Motor neuron disease (MND) comprises a group of fatal neurodegenerative diseases with no effective cure. As progressive motor neuron cell death is one of pathological characteristics of MND, molecules which protect these cells are attractive therapeutic targets. Accumulating evidence indicates that EphA4 activation is involved in MND pathogenesis, and inhibition of EphA4 improves functional outcomes. However, the underlying mechanism of EphA4's function in MND is unclear. In this review, we first present results to demonstrate that EphA4 signalling acts directly on motor neurons to cause cell death. We then review the three most likely mechanisms underlying this effect.
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Affiliation(s)
- Jing Zhao
- Queensland Brain Institute, University of Queensland, Brisbane, QLD 4072, Australia;
| | - Claire H. Stevens
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia;
- School of Chemistry and Molecular Bioscience and Molecular Horizons, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Andrew W. Boyd
- School of Medicine, University of Queensland, Brisbane, QLD 4072, Australia;
| | - Lezanne Ooi
- Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia;
- School of Chemistry and Molecular Bioscience and Molecular Horizons, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Perry F. Bartlett
- Queensland Brain Institute, University of Queensland, Brisbane, QLD 4072, Australia;
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White JJ, Bosman LWJ, Blot FGC, Osório C, Kuppens BW, Krijnen WHJJ, Andriessen C, De Zeeuw CI, Jaarsma D, Schonewille M. Region-specific preservation of Purkinje cell morphology and motor behavior in the ATXN1[82Q] mouse model of spinocerebellar ataxia 1. Brain Pathol 2021; 31:e12946. [PMID: 33724582 PMCID: PMC8412070 DOI: 10.1111/bpa.12946] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 01/27/2021] [Accepted: 02/16/2021] [Indexed: 01/09/2023] Open
Abstract
Purkinje cells are the primary processing units of the cerebellar cortex and display molecular heterogeneity that aligns with differences in physiological properties, projection patterns, and susceptibility to disease. In particular, multiple mouse models that feature Purkinje cell degeneration are characterized by incomplete and patterned Purkinje cell degeneration, suggestive of relative sparing of Purkinje cell subpopulations, such as those expressing Aldolase C/zebrinII (AldoC) or residing in the vestibulo‐cerebellum. Here, we investigated a well‐characterized Purkinje cell‐specific mouse model for spinocerebellar ataxia type 1 (SCA1) that expresses human ATXN1 with a polyQ expansion (82Q). Our pathological analysis confirms previous findings that Purkinje cells of the vestibulo‐cerebellum, i.e., the flocculonodular lobes, and crus I are relatively spared from key pathological hallmarks: somatodendritic atrophy, and the appearance of p62/SQSTM1‐positive inclusions. However, immunohistological analysis of transgene expression revealed that spared Purkinje cells do not express mutant ATXN1 protein, indicating the sparing of Purkinje cells can be explained by an absence of transgene expression. Additionally, we found that Purkinje cells in other cerebellar lobules that typically express AldoC, not only display severe pathology but also show loss of AldoC expression. The relatively preserved flocculonodular lobes and crus I showed a substantial fraction of Purkinje cells that expressed the mutant protein and displayed pathology as well as loss of AldoC expression. Despite considerable pathology in these lobules, behavioral analyses demonstrated a relative sparing of related functions, suggestive of sufficient functional cerebellar reserve. Together, the data indicate that mutant ATXN1 affects both AldoC‐positive and AldoC‐negative Purkinje cells and disrupts normal parasagittal AldoC expression in Purkinje cells. Our results show that, in a mouse model otherwise characterized by widespread Purkinje cell degeneration, sparing of specific subpopulations is sufficient to maintain normal performance of specific behaviors within the context of the functional, modular map of the cerebellum.
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Affiliation(s)
- Joshua J White
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
| | | | | | - Catarina Osório
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
| | - Bram W Kuppens
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
| | | | | | - Chris I De Zeeuw
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands.,Netherlands Institute for Neuroscience, Royal Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Dick Jaarsma
- Department of Neuroscience, Erasmus MC, Rotterdam, Netherlands
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Neuroprotective Effect of Vascular Endothelial Growth Factor on Motoneurons of the Oculomotor System. Int J Mol Sci 2021; 22:ijms22020814. [PMID: 33467517 PMCID: PMC7830098 DOI: 10.3390/ijms22020814] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/11/2021] [Accepted: 01/13/2021] [Indexed: 01/04/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) was initially characterized as a potent angiogenic factor based on its activity on the vascular system. However, it is now well established that VEGF also plays a crucial role as a neuroprotective factor in the nervous system. A deficit of VEGF has been related to motoneuronal degeneration, such as that occurring in amyotrophic lateral sclerosis (ALS). Strikingly, motoneurons of the oculomotor system show lesser vulnerability to neurodegeneration in ALS compared to other motoneurons. These motoneurons presented higher amounts of VEGF and its receptor Flk-1 than other brainstem pools. That higher VEGF level could be due to an enhanced retrograde input from their target muscles, but it can also be produced by the motoneurons themselves and act in an autocrine way. By contrast, VEGF’s paracrine supply from the vicinity cells, such as glial cells, seems to represent a minor source of VEGF for brainstem motoneurons. In addition, ocular motoneurons experiment an increase in VEGF and Flk-1 level in response to axotomy, not observed in facial or hypoglossal motoneurons. Therefore, in this review, we summarize the differences in VEGF availability that could contribute to the higher resistance of extraocular motoneurons to injury and neurodegenerative diseases.
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McCall AL, Dhindsa JS, Pucci LA, Kahn AF, Fusco AF, Biswas DD, Strickland LM, Tseng HC, ElMallah MK. Respiratory pathology in the Optn -/- mouse model of Amyotrophic Lateral Sclerosis. Respir Physiol Neurobiol 2020; 282:103525. [PMID: 32805420 DOI: 10.1016/j.resp.2020.103525] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/29/2020] [Accepted: 08/10/2020] [Indexed: 02/07/2023]
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disorder that results in death due to respiratory failure. Many genetic defects are associated with ALS; one such defect is a mutation in the gene encoding optineurin (OPTN). Using an optineurin null mouse (Optn-/-), we sought to characterize the impact of optineurin deficiency on respiratory neurodegeneration. Respiratory function was assessed at 6 and 12 mo of age using whole body plethysmography at baseline during normoxia (FiO2: 0.21; N2 balance) and during a respiratory challenge with hypoxia and hypercapnia (FiCO2: 0.07, FiO2: 0.10; N2 balance). Histological analyses to assess motor neuron viability and respiratory nerve integrity were performed in the medulla, cervical spinal cord, hypoglossal nerve, and phrenic nerve. Minute ventilation, peak inspiratory flow, and peak expiratory flow are significantly reduced during a respiratory challenge in 6 mo Optn-/-mice. By 12 mo, tidal volume is also significantly reduced in Optn-/- mice. Furthermore, 12mo Optn-/- mice exhibit hypoglossal motor neuron loss, phrenic and hypoglossal dysmyelination, and accumulated mitochondria in the hypoglossal nerve axons. Overall, these data indicate that Optn-/- mice display neurodegenerative respiratory dysfunction and are a useful model to study the impact of novel therapies on respiratory function for optineurin-deficient ALS patients.
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Affiliation(s)
- Angela L McCall
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Justin S Dhindsa
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Logan A Pucci
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Amanda F Kahn
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Anna F Fusco
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Debolina D Biswas
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Laura M Strickland
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA
| | - Henry C Tseng
- Duke Eye Center and Department of Ophthalmology, School of Medicine, Duke University, Durham, North Carolina 27710, USA
| | - Mai K ElMallah
- Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina 27710, USA.
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22
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Nichterwitz S, Nijssen J, Storvall H, Schweingruber C, Comley LH, Allodi I, Lee MVD, Deng Q, Sandberg R, Hedlund E. LCM-seq reveals unique transcriptional adaptation mechanisms of resistant neurons and identifies protective pathways in spinal muscular atrophy. Genome Res 2020; 30:1083-1096. [PMID: 32820007 PMCID: PMC7462070 DOI: 10.1101/gr.265017.120] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 07/10/2020] [Indexed: 11/25/2022]
Abstract
Somatic motor neurons are selectively vulnerable in spinal muscular atrophy (SMA), which is caused by a deficiency of the ubiquitously expressed survival of motor neuron protein. However, some motor neuron groups, including oculomotor and trochlear (ocular), which innervate eye muscles, are for unknown reasons spared. To reveal mechanisms of vulnerability and resistance in SMA, we investigate the transcriptional dynamics in discrete neuronal populations using laser capture microdissection coupled with RNA sequencing (LCM-seq). Using gene correlation network analysis, we reveal a TRP53-mediated stress response that is intrinsic to all somatic motor neurons independent of their vulnerability, but absent in relatively resistant red nucleus and visceral motor neurons. However, the temporal and spatial expression analysis across neuron types shows that the majority of SMA-induced modulations are cell type-specific. Using Gene Ontology and protein network analyses, we show that ocular motor neurons present unique disease-adaptation mechanisms that could explain their resilience. Specifically, ocular motor neurons up-regulate (1) Syt1, Syt5, and Cplx2, which modulate neurotransmitter release; (2) the neuronal survival factors Gdf15, Chl1, and Lif; (3) Aldh4, that protects cells from oxidative stress; and (4) the caspase inhibitor Pak4. Finally, we show that GDF15 can rescue vulnerable human spinal motor neurons from degeneration. This confirms that adaptation mechanisms identified in resilient neurons can be used to reduce susceptibility of vulnerable neurons. In conclusion, this in-depth longitudinal transcriptomics analysis in SMA reveals novel cell type-specific changes that, alone and combined, present compelling targets, including Gdf15, for future gene therapy studies aimed toward preserving vulnerable motor neurons.
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Affiliation(s)
| | - Jik Nijssen
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Helena Storvall
- Department of Cell and Molecular Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Ludwig Institute for Cancer Research, Karolinska Institutet, 171 77 Stockholm, Sweden
| | | | - Laura Helen Comley
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Ilary Allodi
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Mirjam van der Lee
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Qiaolin Deng
- Ludwig Institute for Cancer Research, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Rickard Sandberg
- Department of Cell and Molecular Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
- Ludwig Institute for Cancer Research, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
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23
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Diazoxide blocks or reduces microgliosis when applied prior or subsequent to motor neuron injury in mice. Brain Res 2020; 1741:146875. [PMID: 32389588 DOI: 10.1016/j.brainres.2020.146875] [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: 11/05/2019] [Revised: 04/23/2020] [Accepted: 05/04/2020] [Indexed: 12/11/2022]
Abstract
Diazoxide (DZX), an anti-hypertonic and anti-hypoglycemic drug, was shown to have anti-inflammatory effects in several injured cell types outside the central nervous system. In the brain, the neuroprotective potential of DZX is well described, however, its anticipated anti-inflammatory effect after acute injury has not been systematically analyzed. To disclose the anti-inflammatory effect of DZX in the central nervous system, an injury was induced in the hypoglossal and facial nuclei and in the oculomotor nucleus by unilateral axonal transection and unilateral target deprivation (enucleation), respectively. On the fourth day after surgery, microglial analysis was performed on tissue in which microglia were DAB-labeled and motoneurons were labeled with immunofluorescence. DZX treatment was given either prophylactically, starting 7 days prior to the injury and continuing until the animals were sacrificed, or postoperatively only, with daily intraperitoneal injections (1.25 mg/kg; in 10 mg/ml dimethyl sulfoxide in distilled water). Prophylactically + postoperatively applied DZX completely eliminated the microglial reaction in each motor nuclei. If DZX was applied only postoperatively, some microglial activation could be detected, but its magnitude was still significantly smaller than the non-DZX-treated controls. The effect of DZX could also be demonstrated through an extended period, as tested in the hypoglossal nucleus on day 7 after the operation. Neuronal counts, determined at day 4 after the operation in the hypoglossal nucleus, demonstrated no loss of motor neurons, however, an increased Feret's diameter of mitochondria could be measured, suggesting increased oxidative stress in the injured cells. The increase of mitochondrial Feret's diameter could also be prevented with DZX treatment.
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24
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Nizzardo M, Taiana M, Rizzo F, Aguila Benitez J, Nijssen J, Allodi I, Melzi V, Bresolin N, Comi GP, Hedlund E, Corti S. Synaptotagmin 13 is neuroprotective across motor neuron diseases. Acta Neuropathol 2020; 139:837-853. [PMID: 32065260 PMCID: PMC7181443 DOI: 10.1007/s00401-020-02133-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 12/13/2022]
Abstract
In amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), spinal and lower brainstem motor neurons degenerate, but some motor neuron subtypes are spared, including oculomotor neurons (OMNs). The mechanisms responsible for this selective degeneration are largely unknown, but the molecular signatures of resistant and vulnerable motor neurons are distinct and offer clues to neuronal resilience and susceptibility. Here, we demonstrate that healthy OMNs preferentially express Synaptotagmin 13 (SYT13) compared to spinal motor neurons. In end-stage ALS patients, SYT13 is enriched in both OMNs and the remaining relatively resilient spinal motor neurons compared to controls. Overexpression of SYT13 in ALS and SMA patient motor neurons in vitro improves their survival and increases axon lengths. Gene therapy with Syt13 prolongs the lifespan of ALS mice by 14% and SMA mice by 50% by preserving motor neurons and delaying muscle denervation. SYT13 decreases endoplasmic reticulum stress and apoptosis of motor neurons, both in vitro and in vivo. Thus, SYT13 is a resilience factor that can protect motor neurons and a candidate therapeutic target across motor neuron diseases.
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25
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Liu W, Venugopal S, Majid S, Ahn IS, Diamante G, Hong J, Yang X, Chandler SH. Single-cell RNA-seq analysis of the brainstem of mutant SOD1 mice reveals perturbed cell types and pathways of amyotrophic lateral sclerosis. Neurobiol Dis 2020; 141:104877. [PMID: 32360664 PMCID: PMC7519882 DOI: 10.1016/j.nbd.2020.104877] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/13/2020] [Accepted: 04/22/2020] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which motor neurons throughout the brain and spinal cord progressively degenerate resulting in muscle atrophy, paralysis and death. Recent studies using animal models of ALS implicate multiple cell-types (e.g., astrocytes and microglia) in ALS pathogenesis in the spinal motor systems. To ascertain cellular vulnerability and cell-type specific mechanisms of ALS in the brainstem that orchestrates oral-motor functions, we conducted parallel single cell RNA sequencing (scRNA-seq) analysis using the high-throughput Drop-seq method. We isolated 1894 and 3199 cells from the brainstem of wildtype and mutant SOD1 symptomatic mice respectively, at postnatal day 100. We recovered major known cell types and neuronal subpopulations, such as interneurons and motor neurons, and trigeminal ganglion (TG) peripheral sensory neurons, as well as, previously uncharacterized interneuron subtypes. We found that the majority of the cell types displayed transcriptomic alterations in ALS mice. Differentially expressed genes (DEGs) of individual cell populations revealed cell-type specific alterations in numerous pathways, including previously known ALS pathways such as inflammation (in microglia), stress response (ependymal and an uncharacterized cell population), neurogenesis (astrocytes, oligodendrocytes, neurons), synapse organization and transmission (microglia, oligodendrocyte precursor cells, and neuronal subtypes), and mitochondrial function (uncharacterized cell populations). Other cell-type specific processes altered in SOD1 mutant brainstem include those from motor neurons (axon regeneration, voltage-gated sodium and potassium channels underlying excitability, potassium ion transport), trigeminal sensory neurons (detection of temperature stimulus involved in sensory perception), and cellular response to toxic substances (uncharacterized cell populations). DEGs consistently altered across cell types (e.g., Malat1), as well as cell-type specific DEGs, were identified. Importantly, DEGs from various cell types overlapped with known ALS genes from the literature and with top hits from an existing human ALS genome-wide association study (GWAS), implicating the potential cell types in which the ALS genes function with ALS pathogenesis. Our molecular investigation at single cell resolution provides comprehensive insights into the cell types, genes and pathways altered in the brainstem in a widely used ALS mouse model.
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Affiliation(s)
- Wenting Liu
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - Sharmila Venugopal
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - Sana Majid
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - In Sook Ahn
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - Graciel Diamante
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - Jason Hong
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA
| | - Xia Yang
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA; Brain Research Institute, University of California, Los Angeles, USA; Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, USA.
| | - Scott H Chandler
- Department of Integrative Biology & Physiology, University of California, 2024 Terasaki Bld, 610 Charles E. Young Dr. East, Los Angeles, USA; Brain Research Institute, University of California, Los Angeles, USA.
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26
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Mole AJ, Bell S, Thomson AK, Dissanayake KN, Ribchester RR, Murray LM. Synaptic withdrawal following nerve injury is influenced by postnatal maturity, muscle-specific properties, and the presence of underlying pathology in mice. J Anat 2020; 237:263-274. [PMID: 32311115 PMCID: PMC7369188 DOI: 10.1111/joa.13187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 01/30/2020] [Accepted: 03/02/2020] [Indexed: 01/13/2023] Open
Abstract
Axonal and synaptic degeneration occur following nerve injury and during disease. Traumatic nerve injury results in rapid fragmentation of the distal axon and loss of synaptic terminals, in a process known as Wallerian degeneration (WD). Identifying and understanding factors that influence the rate of WD is of significant biological and clinical importance, as it will facilitate understanding of the mechanisms of neurodegeneration and identification of novel therapeutic targets. Here, we investigate levels of synaptic loss following nerve injury under a range of conditions, including during postnatal development, in a range of anatomically distinct muscles and in a mouse model of motor neuron disease. By utilising an ex vivo model of nerve injury, we show that synaptic withdrawal is slower during early postnatal development. Significantly more neuromuscular junctions remained fully innervated in the cranial nerve/muscle preparations analysed at P15 than at P25. Furthermore, we demonstrate variability in the level of synaptic withdrawal in response to injury in different muscles, with retraction being slower in abdominal preparations than in cranial muscles across all time points analysed. Importantly, differences between the cranial and thoracoabdominal musculature seen here are not consistent with differences in muscle vulnerability that have been previously reported in mouse models of the childhood motor neuron disease, spinal muscular atrophy (SMA), caused by depletion of survival motor neuron protein (Smn). To further investigate the relationship between synaptic degeneration in SMA and WD, we induced WD in preparations from the Smn2B/− mouse model of SMA. In a disease‐resistant muscle (rostral band of levator auris longus), where there is minimal denervation, there was no change in the level of synaptic loss, which suggests that the process of synaptic withdrawal following injury is Smn‐independent. However, in a muscle with ongoing degeneration (transvs. abdominis), the level of synaptic loss significantly increased, with the percentage of denervated endplates increasing by 33% following injury, compared to disease alone. We therefore conclude that the presence of a die‐back can accelerate synaptic loss after injury in Smn2B/− mice.
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Affiliation(s)
- Alannah J Mole
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
| | - Sarah Bell
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
| | - Alison K Thomson
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
| | - Kosala N Dissanayake
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
| | - Richard R Ribchester
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
| | - Lyndsay M Murray
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,The Euan MacDonald Centre for Motor Neurone Disease Research, Edinburgh, UK
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27
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Willis CM, Nicaise AM, Peruzzotti-Jametti L, Pluchino S. The neural stem cell secretome and its role in brain repair. Brain Res 2020; 1729:146615. [DOI: 10.1016/j.brainres.2019.146615] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/05/2019] [Accepted: 12/16/2019] [Indexed: 12/13/2022]
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28
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Cengiz B, Kuruoğlu R. A new parameter to discriminate amyotrophic lateral sclerosis patients from healthy participants by motor cortical excitability changes. Muscle Nerve 2020; 61:354-362. [PMID: 31875983 DOI: 10.1002/mus.26786] [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: 09/03/2019] [Revised: 12/08/2019] [Accepted: 12/22/2019] [Indexed: 12/13/2022]
Abstract
INTRODUCTION We sought a combination of abnormalities to define a more sensitive measure of cortical excitability in amyotrophic lateral sclerosis (ALS). METHODS The automatic threshold tracking method was employed to assess the resting motor threshold, intracortical facilitation (ICF), short-interval intracortical inhibition (SICI), and short-interval intracortical faciilitation (SICF) in patients and controls. RESULTS SICF at interstimulus intervals (ISI) between 1 and 1.8 ms and 2 and 3 ms as well as average SICI and SICI at ISIs of 1 and 2.5 ms were significantly reduced in ALS. The SICI curve was altered, displaying a solitary peak. Discriminant analysis revealed that the combination of SICI 2.5 ms and the mean SICF between 1 and 1.8 ms ISIs was the most sensitive parameter to distinguish patients with ALS from healthy participants. DISCUSSION Along with the reduced SICI and its altered shape, connectivity between motor cortical circuits is changed in ALS. Combination with SICF increases the diagnostic utility of SICI in ALS.
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Affiliation(s)
- Bülent Cengiz
- Department of Neurology, Clinical Neurophysiology Division, Gazi University Faculty of Medicine, Ankara, Turkey
| | - Reha Kuruoğlu
- Department of Neurology, Clinical Neurophysiology Division, Gazi University Faculty of Medicine, Ankara, Turkey
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29
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Circuit-Specific Early Impairment of Proprioceptive Sensory Neurons in the SOD1 G93A Mouse Model for ALS. J Neurosci 2019; 39:8798-8815. [PMID: 31530644 DOI: 10.1523/jneurosci.1214-19.2019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/24/2019] [Accepted: 09/02/2019] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which motor neurons degenerate, resulting in muscle atrophy, paralysis, and fatality. Studies using mouse models of ALS indicate a protracted period of disease development with progressive motor neuron pathology, evident as early as embryonic and postnatal stages. Key missing information includes concomitant alterations in the sensorimotor circuit essential for normal development and function of the neuromuscular system. Leveraging unique brainstem circuitry, we show in vitro evidence for reflex circuit-specific postnatal abnormalities in the jaw proprioceptive sensory neurons in the well-studied SOD1G93A mouse. These include impaired and arrhythmic action potential burst discharge associated with a deficit in Nav1.6 Na+ channels. However, the mechanoreceptive and nociceptive trigeminal ganglion neurons and the visual sensory retinal ganglion neurons were resistant to excitability changes in age-matched SOD1G93A mice. Computational modeling of the observed disruption in sensory patterns predicted asynchronous self-sustained motor neuron discharge suggestive of imminent reflexive defects, such as muscle fasciculations in ALS. These results demonstrate a novel reflex circuit-specific proprioceptive sensory abnormality in ALS.SIGNIFICANCE STATEMENT Neurodegenerative diseases have prolonged periods of disease development and progression. Identifying early markers of vulnerability can therefore help devise better diagnostic and treatment strategies. In this study, we examined postnatal abnormalities in the electrical excitability of muscle spindle afferent proprioceptive neurons in the well-studied SOD1G93A mouse model for neurodegenerative motor neuron disease, amyotrophic lateral sclerosis. Our findings suggest that these proprioceptive sensory neurons are exclusively afflicted early in the disease process relative to sensory neurons of other modalities. Moreover, they presented Nav1.6 Na+ channel deficiency, which contributed to arrhythmic burst discharge. Such sensory arrhythmia could initiate reflexive defects, such as muscle fasciculations in amyotrophic lateral sclerosis, as suggested by our computational model.
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30
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Ragagnin AMG, Shadfar S, Vidal M, Jamali MS, Atkin JD. Motor Neuron Susceptibility in ALS/FTD. Front Neurosci 2019; 13:532. [PMID: 31316328 PMCID: PMC6610326 DOI: 10.3389/fnins.2019.00532] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 05/08/2019] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the death of both upper and lower motor neurons (MNs) in the brain, brainstem and spinal cord. The neurodegenerative mechanisms leading to MN loss in ALS are not fully understood. Importantly, the reasons why MNs are specifically targeted in this disorder are unclear, when the proteins associated genetically or pathologically with ALS are expressed ubiquitously. Furthermore, MNs themselves are not affected equally; specific MNs subpopulations are more susceptible than others in both animal models and human patients. Corticospinal MNs and lower somatic MNs, which innervate voluntary muscles, degenerate more readily than specific subgroups of lower MNs, which remain resistant to degeneration, reflecting the clinical manifestations of ALS. In this review, we discuss the possible factors intrinsic to MNs that render them uniquely susceptible to neurodegeneration in ALS. We also speculate why some MN subpopulations are more vulnerable than others, focusing on both their molecular and physiological properties. Finally, we review the anatomical network and neuronal microenvironment as determinants of MN subtype vulnerability and hence the progression of ALS.
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Affiliation(s)
- Audrey M G Ragagnin
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sina Shadfar
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Marta Vidal
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Md Shafi Jamali
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Julie D Atkin
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
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31
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Allodi I, Nijssen J, Benitez JA, Schweingruber C, Fuchs A, Bonvicini G, Cao M, Kiehn O, Hedlund E. Modeling Motor Neuron Resilience in ALS Using Stem Cells. Stem Cell Reports 2019; 12:1329-1341. [PMID: 31080111 PMCID: PMC6565614 DOI: 10.1016/j.stemcr.2019.04.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 04/05/2019] [Accepted: 04/08/2019] [Indexed: 12/17/2022] Open
Abstract
Oculomotor neurons, which regulate eye movement, are resilient to degeneration in the lethal motor neuron disease amyotrophic lateral sclerosis (ALS). It would be highly advantageous if motor neuron resilience could be modeled in vitro. Toward this goal, we generated a high proportion of oculomotor neurons from mouse embryonic stem cells through temporal overexpression of PHOX2A in neuronal progenitors. We demonstrate, using electrophysiology, immunocytochemistry, and RNA sequencing, that in vitro-generated neurons are bona fide oculomotor neurons based on their cellular properties and similarity to their in vivo counterpart in rodent and man. We also show that in vitro-generated oculomotor neurons display a robust activation of survival-promoting Akt signaling and are more resilient to the ALS-like toxicity of kainic acid than spinal motor neurons. Thus, we can generate bona fide oculomotor neurons in vitro that display a resilience similar to that seen in vivo. Bona fide oculomotor neurons can be derived from stem cells by PHOX2A overexpression In vitro- and in vivo-generated oculomotor neurons are transcriptionally similar Stem cell-derived oculomotor neurons display a robust activation of Akt signaling In vitro-generated oculomotor neurons are relatively resilient to ALS-like toxicity
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Affiliation(s)
- Ilary Allodi
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jik Nijssen
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Andrea Fuchs
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Gillian Bonvicini
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ming Cao
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ole Kiehn
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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32
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Simandi Z, Pajer K, Karolyi K, Sieler T, Jiang LL, Kolostyak Z, Sari Z, Fekecs Z, Pap A, Patsalos A, Contreras GA, Reho B, Papp Z, Guo X, Horvath A, Kiss G, Keresztessy Z, Vámosi G, Hickman J, Xu H, Dormann D, Hortobagyi T, Antal M, Nógrádi A, Nagy L. Arginine Methyltransferase PRMT8 Provides Cellular Stress Tolerance in Aging Motoneurons. J Neurosci 2018; 38:7683-7700. [PMID: 30054395 PMCID: PMC6113905 DOI: 10.1523/jneurosci.3389-17.2018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 06/22/2018] [Accepted: 06/25/2018] [Indexed: 02/07/2023] Open
Abstract
Aging contributes to cellular stress and neurodegeneration. Our understanding is limited regarding the tissue-restricted mechanisms providing protection in postmitotic cells throughout life. Here, we show that spinal cord motoneurons exhibit a high abundance of asymmetric dimethyl arginines (ADMAs) and the presence of this posttranslational modification provides protection against environmental stress. We identify protein arginine methyltransferase 8 (PRMT8) as a tissue-restricted enzyme responsible for proper ADMA level in postmitotic neurons. Male PRMT8 knock-out mice display decreased muscle strength with aging due to premature destabilization of neuromuscular junctions. Mechanistically, inhibition of methyltransferase activity or loss of PRMT8 results in accumulation of unrepaired DNA double-stranded breaks and decrease in the cAMP response-element-binding protein 1 (CREB1) level. As a consequence, the expression of CREB1-mediated prosurvival and regeneration-associated immediate early genes is dysregulated in aging PRMT8 knock-out mice. The uncovered role of PRMT8 represents a novel mechanism of stress tolerance in long-lived postmitotic neurons and identifies PRMT8 as a tissue-specific therapeutic target in the prevention of motoneuron degeneration.SIGNIFICANCE STATEMENT Although most of the cells in our body have a very short lifespan, postmitotic neurons must survive for many decades. Longevity of a cell within the organism depends on its ability to properly regulate signaling pathways that counteract perturbations, such as DNA damage, oxidative stress, or protein misfolding. Here, we provide evidence that tissue-specific regulators of stress tolerance exist in postmitotic neurons. Specifically, we identify protein arginine methyltransferase 8 (PRMT8) as a cell-type-restricted arginine methyltransferase in spinal cord motoneurons (MNs). PRMT8-dependent arginine methylation is required for neuroprotection against age-related increased of cellular stress. Tissue-restricted expression and the enzymatic activity of PRMT8 make it an attractive target for drug development to delay the onset of neurodegenerative disorders.
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Affiliation(s)
- Zoltan Simandi
- Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida 32827
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Krisztian Pajer
- Department of Anatomy, Histology and Embryology, University of Szeged, Szeged, Hungary, HU 6720
| | - Katalin Karolyi
- Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida 32827
| | - Tatiana Sieler
- Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida 32827
| | - Lu-Lin Jiang
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037
| | - Zsuzsanna Kolostyak
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Zsanett Sari
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Zoltan Fekecs
- Department of Anatomy, Histology and Embryology, University of Szeged, Szeged, Hungary, HU 6720
| | - Attila Pap
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Andreas Patsalos
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Gerardo Alvarado Contreras
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Balint Reho
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Zoltan Papp
- Division of Clinical Physiology, Institute of Cardiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Xiufang Guo
- NanoScience Technology Center, University of Central Florida, Orlando, Florida 32816
| | - Attila Horvath
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Greta Kiss
- Department of Anatomy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Zsolt Keresztessy
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - György Vámosi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
| | - James Hickman
- NanoScience Technology Center, University of Central Florida, Orlando, Florida 32816
| | - Huaxi Xu
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037
| | - Dorothee Dormann
- BioMedical Center, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany 80539
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany 80539
| | - Tibor Hortobagyi
- HAS-UD Cerebrovascular and Neurodegenerative Research Group, Department of Neurology and Neuropathology, University of Debrecen, Debrecen, Hungary, HU 4032
| | - Miklos Antal
- Department of Anatomy, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
- HAS-UD Neuroscience Research Group, University of Debrecen, Debrecen, Hungary, HU 4032, and
| | - Antal Nógrádi
- Department of Anatomy, Histology and Embryology, University of Szeged, Szeged, Hungary, HU 6720
| | - Laszlo Nagy
- Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida 32827,
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary, HU 4032
- HAS-UD Momentum Immunogenomics Research Group, University of Debrecen, Debrecen, Hungary, HU 4032
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Misawa H, Morisaki Y. [Motor neuron heterogeneity and selective vulnerability in ALS]. Nihon Yakurigaku Zasshi 2018; 152:64-69. [PMID: 30101862 DOI: 10.1254/fpj.152.64] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Different and selective vulnerability among motor neuron subtypes are a fundamental, but unexplained, feature of amyotrophic lateral sclerosis (ALS): fast-fatigable (FF) motor neurons are the most vulnerable, and fast fatigue-resistant/slow (FR/S) motor neurons are relatively resistant. We identified that osteopontin (OPN) can serve as a marker of FR/S motor neurons, whereas matrix metalloproteinase-9 (MMP9) is expressed by FF motor neurons in mice. In SOD1G93A ALS model mice, as the disease progressed, OPN was secreted and accumulated as granular deposits in the extracellular matrix. We also detected OPN/MMP9 co-expressed motor neurons around the disease onset. These double positive motor neurons showed the expression of αvβ3 integrin (OPN receptor) and up-regulation of ER stress markers. We discovered that the double positive motor neurons are remodeled FR/S motor neurons, which compensated for FF motor neuron degeneration (the first wave of degeneration). Genetic ablation of OPN delayed the onset of disease, but later accelerated disease progression. This reflects two modes of OPN involvement in the pathogenesis of ALS: cell-autonomous and non-cell-autonomous effects on motor neuron vulnerability. Our study suggests that OPN expressed in FR/S motor neurons is involved in the second wave of motor neuron degeneration in ALS, and an OPN-αvβ3 integrin-MMP9 axis could be a potentially useful therapeutic target for ALS.
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Affiliation(s)
- Hidemi Misawa
- Division of Pharmacology, Faculty of Pharmacy, Keio University
| | - Yuta Morisaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University
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Starr A, Sattler R. Synaptic dysfunction and altered excitability in C9ORF72 ALS/FTD. Brain Res 2018; 1693:98-108. [PMID: 29453960 DOI: 10.1016/j.brainres.2018.02.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/06/2018] [Accepted: 02/10/2018] [Indexed: 02/08/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is characterized by a progressive degeneration of upper and lower motor neurons, resulting in fatal paralysis due to denervation of the muscle. Due to genetic, pathological and symptomatic overlap, ALS is now considered a spectrum disease together with frontotemporal dementia (FTD), the second most common cause of dementia in individuals under the age of 65. Interestingly, in both diseases, there is a large prevalence of RNA binding proteins (RBPs) that are mutated and considered disease-causing, or whose dysfunction contribute to disease pathogenesis. The most common shared genetic mutation in ALS/FTD is a hexanucleuotide repeat expansion within intron 1 of C9ORF72 (C9). Three potentially overlapping, putative toxic mechanisms have been proposed: loss of function due to haploinsufficient expression of the C9ORF72 mRNA, gain of function of the repeat RNA aggregates, or RNA foci, and repeat-associated non-ATG-initiated translation (RAN) of the repeat RNA into toxic dipeptide repeats (DPRs). Regardless of the causative mechanism, disease symptoms are ultimately caused by a failure of neurotransmission in three regions: the brain, the spinal cord, and the neuromuscular junction. Here, we review C9 ALS/FTD-associated synaptic dysfunction and aberrant neuronal excitability in these three key regions, focusing on changes in morphology and synapse formation, excitability, and excitotoxicity in patients, animal models, and in vitro models. We compare these deficits to those seen in other forms of ALS and FTD in search of shared pathways, and discuss the potential targeting of synaptic dysfunctions for therapeutic intervention in ALS and FTD patients.
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Affiliation(s)
- Alexander Starr
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013, United States
| | - Rita Sattler
- Division of Neurobiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013, United States.
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Nijssen J, Comley LH, Hedlund E. Motor neuron vulnerability and resistance in amyotrophic lateral sclerosis. Acta Neuropathol 2017; 133:863-885. [PMID: 28409282 PMCID: PMC5427160 DOI: 10.1007/s00401-017-1708-8] [Citation(s) in RCA: 196] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/29/2017] [Accepted: 04/01/2017] [Indexed: 12/11/2022]
Abstract
In the fatal disease-amyotrophic lateral sclerosis (ALS)-upper (corticospinal) motor neurons (MNs) and lower somatic MNs, which innervate voluntary muscles, degenerate. Importantly, certain lower MN subgroups are relatively resistant to degeneration, even though pathogenic proteins are typically ubiquitously expressed. Ocular MNs (OMNs), including the oculomotor, trochlear and abducens nuclei (CNIII, IV and VI), which regulate eye movement, persist throughout the disease. Consequently, eye-tracking devices are used to enable paralysed ALS patients (who can no longer speak) to communicate. Additionally, there is a gradient of vulnerability among spinal MNs. Those innervating fast-twitch muscle are most severely affected and degenerate first. MNs innervating slow-twitch muscle can compensate temporarily for the loss of their neighbours by re-innervating denervated muscle until later in disease these too degenerate. The resistant OMNs and the associated extraocular muscles (EOMs) are anatomically and functionally very different from other motor units. The EOMs have a unique set of myosin heavy chains, placing them outside the classical characterization spectrum of all skeletal muscle. Moreover, EOMs have multiple neuromuscular innervation sites per single myofibre. Spinal fast and slow motor units show differences in their dendritic arborisations and the number of myofibres they innervate. These motor units also differ in their functionality and excitability. Identifying the molecular basis of cell-intrinsic pathways that are differentially activated between resistant and vulnerable MNs could reveal mechanisms of selective neuronal resistance, degeneration and regeneration and lead to therapies preventing progressive MN loss in ALS. Illustrating this, overexpression of OMN-enriched genes in spinal MNs, as well as suppression of fast spinal MN-enriched genes can increase the lifespan of ALS mice. Here, we discuss the pattern of lower MN degeneration in ALS and review the current literature on OMN resistance in ALS and differential spinal MN vulnerability. We also reflect upon the non-cell autonomous components that are involved in lower MN degeneration in ALS.
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Silva-Hucha S, Hernández RG, Benítez-Temiño B, Pastor ÁM, de la Cruz RR, Morcuende S. Extraocular motoneurons of the adult rat show higher levels of vascular endothelial growth factor and its receptor Flk-1 than other cranial motoneurons. PLoS One 2017; 12:e0178616. [PMID: 28570669 PMCID: PMC5453543 DOI: 10.1371/journal.pone.0178616] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/16/2017] [Indexed: 12/23/2022] Open
Abstract
Recent studies show a relationship between the deficit of vascular endothelial growth factor (VEGF) and motoneuronal degeneration, such as that occurring in amyotrophic lateral sclerosis (ALS). VEGF delivery protects motoneurons from cell death and delayed neurodegeneration in animal models of ALS. Strikingly, extraocular motoneurons show lesser vulnerability to neurodegeneration in ALS compared to other cranial or spinal motoneurons. Therefore, the present study investigates possible differences in VEGF and its main receptor VEGFR-2 or Flk-1 between extraocular and non-extraocular brainstem motoneurons. We performed immunohistochemistry and Western blot to determine the presence of VEGF and Flk-1 in rat motoneurons located in the three extraocular motor nuclei (abducens, trochlear and oculomotor) and to compare it to that observed in two other brainstem nuclei (hypoglossal and facial) that are vulnerable to degeneration. Extraocular motoneurons presented higher amounts of VEGF and its receptor Flk-1 than other brainstem motoneurons, and thus these molecules could be participating in their higher resistance to neurodegeneration. In conclusion, we hypothesize that differences in VEGF availability and signaling could be a contributing factor to the different susceptibility of extraocular motoneurons, when compared with other motoneurons, in neurodegenerative diseases.
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Affiliation(s)
- Silvia Silva-Hucha
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Rosendo G. Hernández
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Beatriz Benítez-Temiño
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Ángel M. Pastor
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Rosa R. de la Cruz
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Sara Morcuende
- Laboratorio de Fisiología y Plasticidad Neuronal, Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
- * E-mail:
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38
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Oberstadt M, Claßen J, Arendt T, Holzer M. TDP-43 and Cytoskeletal Proteins in ALS. Mol Neurobiol 2017; 55:3143-3151. [PMID: 28466273 DOI: 10.1007/s12035-017-0543-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 04/07/2017] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) represents a rapidly progressing neurodegenerative disease and is characterized by a degeneration of motor neurons. Motor neurons are particularly susceptible to selective and early degeneration because of their extended axon length and their dependency on the cytoskeleton for its stability, signaling, and axonal transport. The motor neuron cytoskeleton comprises actin filaments, neurofilaments like peripherin, and microtubules. The Transactivating Response Region (TAR) DNA Binding Protein (TDP-43) forms characteristic cytoplasmic aggregates in motor neurons of ALS patients, and at least in part, the pathogenesis of ALS seems to be driven by toxic pTDP-43 aggregates in cytoplasm, which lead to a diminished axon formation and reduced axon length. Diminished axon formation and reduced axon length suggest an interaction of TDP-43 with the cytoskeleton of motor neurons. TDP-43 interacts with several cytoskeletal components, e.g., the microtubule-associated protein 1B (MAP1B) or the neurofilament light chain (NFL) through direct binding to its RNA. From a clinical perspective, cytoskeletal biomarkers like phosphorylated neurofilament heavy chain (pNFH) and NFL are already clinically used in ALS patients to predict survival, disease progression, and duration. Thus, in this review, we focus on the interaction of TDP-43 with the different cytoskeleton components such as actin filaments, neurofilaments, and microtubules as well as their associated proteins as one aspect in the complex pathogenesis of ALS.
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Affiliation(s)
- Moritz Oberstadt
- Department of Neurology, University of Leipzig, Liebigstraße 20, 04103, Leipzig, Germany.
| | - Joseph Claßen
- Department of Neurology, University of Leipzig, Liebigstraße 20, 04103, Leipzig, Germany
| | - Thomas Arendt
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
| | - Max Holzer
- Department for Molecular and Cellular Mechanisms of Neurodegeneration, Paul Flechsig Institute for Brain Research, University of Leipzig, Liebigstraße 19, 04103, Leipzig, Germany
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Boyd PJ, Tu WY, Shorrock HK, Groen EJN, Carter RN, Powis RA, Thomson SR, Thomson D, Graham LC, Motyl AAL, Wishart TM, Highley JR, Morton NM, Becker T, Becker CG, Heath PR, Gillingwater TH. Bioenergetic status modulates motor neuron vulnerability and pathogenesis in a zebrafish model of spinal muscular atrophy. PLoS Genet 2017; 13:e1006744. [PMID: 28426667 PMCID: PMC5417717 DOI: 10.1371/journal.pgen.1006744] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 05/04/2017] [Accepted: 04/05/2017] [Indexed: 11/18/2022] Open
Abstract
Degeneration and loss of lower motor neurons is the major pathological hallmark of spinal muscular atrophy (SMA), resulting from low levels of ubiquitously-expressed survival motor neuron (SMN) protein. One remarkable, yet unresolved, feature of SMA is that not all motor neurons are equally affected, with some populations displaying a robust resistance to the disease. Here, we demonstrate that selective vulnerability of distinct motor neuron pools arises from fundamental modifications to their basal molecular profiles. Comparative gene expression profiling of motor neurons innervating the extensor digitorum longus (disease-resistant), gastrocnemius (intermediate vulnerability), and tibialis anterior (vulnerable) muscles in mice revealed that disease susceptibility correlates strongly with a modified bioenergetic profile. Targeting of identified bioenergetic pathways by enhancing mitochondrial biogenesis rescued motor axon defects in SMA zebrafish. Moreover, targeting of a single bioenergetic protein, phosphoglycerate kinase 1 (Pgk1), was found to modulate motor neuron vulnerability in vivo. Knockdown of pgk1 alone was sufficient to partially mimic the SMA phenotype in wild-type zebrafish. Conversely, Pgk1 overexpression, or treatment with terazosin (an FDA-approved small molecule that binds and activates Pgk1), rescued motor axon phenotypes in SMA zebrafish. We conclude that global bioenergetics pathways can be therapeutically manipulated to ameliorate SMA motor neuron phenotypes in vivo.
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Affiliation(s)
- Penelope J. Boyd
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Wen-Yo Tu
- Sheffield Institute for Translation Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Hannah K. Shorrock
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Ewout J. N. Groen
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Roderick N. Carter
- University/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Queens Medical Research Institute, Edinburgh, United Kingdom
| | - Rachael A. Powis
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Sophie R. Thomson
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Derek Thomson
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Laura C. Graham
- Division of Neurobiology, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Anna A. L. Motyl
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Thomas M. Wishart
- Division of Neurobiology, Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - J. Robin Highley
- Sheffield Institute for Translation Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Nicholas M. Morton
- University/British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Queens Medical Research Institute, Edinburgh, United Kingdom
| | - Thomas Becker
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Neuroregeneration, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Catherina G. Becker
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Neuroregeneration, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Paul R. Heath
- Sheffield Institute for Translation Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Thomas H. Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Integrative Physiology, Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail:
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Sivaramakrishnan S, Lynch WP. Rebound from Inhibition: Self-Correction against Neurodegeneration? JOURNAL OF CLINICAL & CELLULAR IMMUNOLOGY 2017; 8:492. [PMID: 28775912 PMCID: PMC5538264 DOI: 10.4172/2155-9899.1000492] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Neural networks play a critical role in establishing constraints on excitability in the central nervous system. Several recent studies have suggested that network dysfunction in the brain and spinal cord are compromised following insult by a neurodegenerative trigger and might precede eventual neuronal loss and neurological impairment. Early intervention of network excitability and plasticity might therefore be critical in resetting hyperexcitability and preventing later neuronal damage. Here, the behavior of neurons that generate burst firing upon recovery from inhibitory input or intrinsic membrane hyperpolarization (rebound neurons) is examined in the context of neural networks that underlie rhythmic activity observed in areas of the brain and spinal cord that are vulnerable to neurodegeneration. In a non-inflammatory rodent model of spongiform neurodegenerative disease triggered by retrovirus infection of glia, rebound neurons are particularly vulnerable to neurodegeneration, likely due to an inherently low calcium buffering capacity. The dysfunction of rebound neurons translates into a dysfunction of rhythmic neural circuits, compromising normal neurological function and leading to eventual morbidity. Understanding how virus infection of glia can mediate dysfunction of rebound neurons, induce hyperexcitability and loss of rhythmic function, pathologic features observed in neurodegenerative disorders ranging from epilepsy to motor neuron disease, might therefore suggest a common pathway for early therapeutic intervention.
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Affiliation(s)
- Shobhana Sivaramakrishnan
- Department of Otolaryngology, Sensory Neuroscience Research Center, West Virginia University School of Medicine, Morgantown, WV 26506, USA
| | - William P. Lynch
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272, USA
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Schaller S, Buttigieg D, Alory A, Jacquier A, Barad M, Merchant M, Gentien D, de la Grange P, Haase G. Novel combinatorial screening identifies neurotrophic factors for selective classes of motor neurons. Proc Natl Acad Sci U S A 2017; 114:E2486-E2493. [PMID: 28270618 PMCID: PMC5373341 DOI: 10.1073/pnas.1615372114] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Numerous neurotrophic factors promote the survival of developing motor neurons but their combinatorial actions remain poorly understood; to address this, we here screened 66 combinations of 12 neurotrophic factors on pure, highly viable, and standardized embryonic mouse motor neurons isolated by a unique FACS technique. We demonstrate potent, strictly additive, survival effects of hepatocyte growth factor (HGF), ciliary neurotrophic factor (CNTF), and Artemin through specific activation of their receptor complexes in distinct subsets of lumbar motor neurons: HGF supports hindlimb motor neurons through c-Met; CNTF supports subsets of axial motor neurons through CNTFRα; and Artemin acts as the first survival factor for parasympathetic preganglionic motor neurons through GFRα3/Syndecan-3 activation. These data show that neurotrophic factors can selectively promote the survival of distinct classes of embryonic motor neurons. Similar studies on postnatal motor neurons may provide a conceptual framework for the combined therapeutic use of neurotrophic factors in degenerative motor neuron diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy, and spinobulbar muscular atrophy.
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Affiliation(s)
- Sébastien Schaller
- Institut de Neurosciences de la Timone, UMR 7289 CNRS, Aix-Marseille University, 13005 Marseille, France
| | - Dorothée Buttigieg
- Institut de Neurosciences de la Timone, UMR 7289 CNRS, Aix-Marseille University, 13005 Marseille, France
| | - Alysson Alory
- Institut de Neurosciences de la Timone, UMR 7289 CNRS, Aix-Marseille University, 13005 Marseille, France
| | - Arnaud Jacquier
- Institut de Neurosciences de la Timone, UMR 7289 CNRS, Aix-Marseille University, 13005 Marseille, France
| | - Marc Barad
- Centre d'Immunologie de Marseille-Luminy (CIML), CNRS, INSERM, Aix-Marseille University, 13288 Marseille, France
| | | | - David Gentien
- Institut Curie, Translational Research Department, Genomic Platform, PSL Research University, 75248 Paris, France
| | - Pierre de la Grange
- GenoSplice Technology, Institut du Cerveau et de la Moëlle (ICM), Hôpital Pitié Salpêtrière, 75013 Paris, France
| | - Georg Haase
- Institut de Neurosciences de la Timone, UMR 7289 CNRS, Aix-Marseille University, 13005 Marseille, France;
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Bonafede R, Mariotti R. ALS Pathogenesis and Therapeutic Approaches: The Role of Mesenchymal Stem Cells and Extracellular Vesicles. Front Cell Neurosci 2017; 11:80. [PMID: 28377696 PMCID: PMC5359305 DOI: 10.3389/fncel.2017.00080] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 03/08/2017] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive muscle paralysis determined by the degeneration of motoneurons in the motor cortex brainstem and spinal cord. The ALS pathogenetic mechanisms are still unclear, despite the wealth of studies demonstrating the involvement of several altered signaling pathways, such as mitochondrial dysfunction, glutamate excitotoxicity, oxidative stress and neuroinflammation. To date, the proposed therapeutic strategies are targeted to one or a few of these alterations, resulting in only a minimal effect on disease course and survival of ALS patients. The involvement of different mechanisms in ALS pathogenesis underlines the need for a therapeutic approach targeted to multiple aspects. Mesenchymal stem cells (MSC) can support motoneurons and surrounding cells, reduce inflammation, stimulate tissue regeneration and release growth factors. On this basis, MSC have been proposed as promising candidates to treat ALS. However, due to the drawbacks of cell therapy, the possible therapeutic use of extracellular vesicles (EVs) released by stem cells is raising increasing interest. The present review summarizes the main pathological mechanisms involved in ALS and the related therapeutic approaches proposed to date, focusing on MSC therapy and their preclinical and clinical applications. Moreover, the nature and characteristics of EVs and their role in recapitulating the effect of stem cells are discussed, elucidating how and why these vesicles could provide novel opportunities for ALS treatment.
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Affiliation(s)
- Roberta Bonafede
- Department of Neuroscience, Biomedicine and Movement Sciences, University of VeronaVerona, Italy
| | - Raffaella Mariotti
- Department of Neuroscience, Biomedicine and Movement Sciences, University of VeronaVerona, Italy
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Arbour D, Vande Velde C, Robitaille R. New perspectives on amyotrophic lateral sclerosis: the role of glial cells at the neuromuscular junction. J Physiol 2016; 595:647-661. [PMID: 27633977 DOI: 10.1113/jp270213] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 09/12/2016] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a disease leading to the death of motor neurons (MNs). It is also recognized as a non-cell autonomous disease where glial cells in the CNS are involved in its pathogenesis and progression. However, although denervation of neuromuscular junctions (NMJs) represents an early and major event in ALS, the importance of glial cells at this synapse receives little attention. An interesting possibility is that altered relationships between glial cells and MNs in the spinal cord in ALS may also take place at the NMJ. Perisynaptic Schwann cells (PSCs), which are glial cells at the NMJ, show great morphological and functional adaptability to ensure NMJ stability, maintenance and repair. More specifically, PSCs change their properties according to the state of innervation. Hence, abnormal changes or lack of changes can have detrimental effects on NMJs in ALS. This review will provide an overview of known and hypothesized interactions between MN nerve terminals and PSCs at NMJs during development, aging and ALS-induced denervation. These neuron-PSC interactions may be crucial to the understanding of how degenerative changes begin and progress at NMJs in ALS, and represent a novel therapeutic target.
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Affiliation(s)
- Danielle Arbour
- Département de neurosciences, Université de Montréal, Montréal, Québec, Canada, H3C 3J7.,Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Québec, Canada, H3C 3J7
| | - Christine Vande Velde
- Département de neurosciences, Université de Montréal, Montréal, Québec, Canada, H3C 3J7.,Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Québec, Canada, H3C 3J7.,Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada, H2X 0A9
| | - Richard Robitaille
- Département de neurosciences, Université de Montréal, Montréal, Québec, Canada, H3C 3J7.,Groupe de recherche sur le système nerveux central, Université de Montréal, Montréal, Québec, Canada, H3C 3J7
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Corsini S, Tortora M, Nistri A. Nicotinic receptor activation contrasts pathophysiological bursting and neurodegeneration evoked by glutamate uptake block on rat hypoglossal motoneurons. J Physiol 2016; 594:6777-6798. [PMID: 27374167 PMCID: PMC5108918 DOI: 10.1113/jp272591] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 06/21/2016] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Impaired uptake of glutamate builds up the extracellular level of this excitatory transmitter to trigger rhythmic neuronal bursting and delayed cell death in the brainstem motor nucleus hypoglossus. This process is the expression of the excitotoxicity that underlies motoneuron degeneration in diseases such as amyotrophic lateral sclerosis affecting bulbar motoneurons. In a model of motoneuron excitotoxicity produced by pharmacological block of glutamate uptake in vitro, rhythmic bursting is suppressed by activation of neuronal nicotinic receptors with their conventional agonist nicotine. Emergence of bursting is facilitated by nicotinic receptor antagonists. Following excitotoxicity, nicotinic receptor activity decreases mitochondrial energy dysfunction, endoplasmic reticulum stress and production of toxic radicals. Globally, these phenomena synergize to provide motoneuron protection. Nicotinic receptors may represent a novel target to contrast pathological overactivity of brainstem motoneurons and therefore to prevent their metabolic distress and death. ABSTRACT Excitotoxicity is thought to be one of the early processes in the onset of amyotrophic lateral sclerosis (ALS) because high levels of glutamate have been detected in the cerebrospinal fluid of such patients due to dysfunctional uptake of this transmitter that gradually damages brainstem and spinal motoneurons. To explore potential mechanisms to arrest ALS onset, we used an established in vitro model of rat brainstem slice preparation in which excitotoxicity is induced by the glutamate uptake blocker dl-threo-β-benzyloxyaspartate (TBOA). Because certain brain neurons may be neuroprotected via activation of nicotinic acetylcholine receptors (nAChRs) by nicotine, we investigated if nicotine could arrest excitotoxic damage to highly ALS-vulnerable hypoglossal motoneurons (HMs). On 50% of patch-clamped HMs, TBOA induced intense network bursts that were inhibited by 1-10 μm nicotine, whereas nAChR antagonists facilitated burst emergence in non-burster cells. Furthermore, nicotine inhibited excitatory transmission and enhanced synaptic inhibition. Strong neuroprotection by nicotine prevented the HM loss observed after 4 h of TBOA exposure. This neuroprotective action was due to suppression of downstream effectors of neurotoxicity such as increased intracellular levels of reactive oxygen species, impaired energy metabolism and upregulated genes involved in endoplasmic reticulum (ER) stress. In addition, HMs surviving TBOA toxicity often expressed UDP-glucose glycoprotein glucosyltransferase, a key element in repair of misfolded proteins: this phenomenon was absent after nicotine application, indicative of ER stress prevention. Our results suggest nAChRs to be potential targets for inhibiting excitotoxic damage of motoneurons at an early stage of the neurodegenerative process.
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Affiliation(s)
- Silvia Corsini
- Department of NeuroscienceInternational School for Advanced Studies (SISSA)TriesteItaly
| | - Maria Tortora
- Department of NeuroscienceInternational School for Advanced Studies (SISSA)TriesteItaly
| | - Andrea Nistri
- Department of NeuroscienceInternational School for Advanced Studies (SISSA)TriesteItaly
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Abstract
PURPOSE OF REVIEW Abnormalities of oculomotor control accompany the pathological changes underlying many neurodegenerative diseases. Clinical examination of eye movements can contribute to differential diagnosis, whereas quantitative laboratory measures can provide detailed insight into the disease process. In this review of eye movements in neurodegenerative disease, we summarise recent empirical findings and conceptual advances. RECENT FINDINGS Oculomotor researchers continue to be particularly prolific in studying Parkinson's disease but there is also substantial activity in Alzheimer's disease and spinocerebellar ataxia. Interesting findings have been reported in Huntington's, motor neuron disease, and glaucoma. Most studies report laboratory-based investigations but useful progress in clinical description continues to be made. SUMMARY Eye movements remain an active field of investigation across a variety of neurodegenerative conditions. Progress continues to be made at the clinical level as well by using laboratory techniques.
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Affiliation(s)
- Michael R MacAskill
- aNew Zealand Brain Research Institute bDepartment of Medicine, University of Otago cDepartment of Neurology, Christchurch Hospital, Christchurch, New Zealand
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Morisaki Y, Niikura M, Watanabe M, Onishi K, Tanabe S, Moriwaki Y, Okuda T, Ohara S, Murayama S, Takao M, Uchida S, Yamanaka K, Misawa H. Selective Expression of Osteopontin in ALS-resistant Motor Neurons is a Critical Determinant of Late Phase Neurodegeneration Mediated by Matrix Metalloproteinase-9. Sci Rep 2016; 6:27354. [PMID: 27264390 PMCID: PMC4893611 DOI: 10.1038/srep27354] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 05/17/2016] [Indexed: 12/13/2022] Open
Abstract
Differential vulnerability among motor neuron (MN) subtypes is a fundamental feature of amyotrophic lateral sclerosis (ALS): fast-fatigable (FF) MNs are more vulnerable than fast fatigue-resistant (FR) or slow (S) MNs. The reason for this selective vulnerability remains enigmatic. We report here that the extracellular matrix (ECM) protein osteopontin (OPN) is selectively expressed by FR and S MNs and ALS-resistant motor pools, whereas matrix metalloproteinase-9 (MMP-9) is selectively expressed by FF MNs. OPN is secreted and accumulated as extracellular granules in ECM in three ALS mouse models and a human ALS patient. In SOD1(G93A) mice, OPN/MMP-9 double positivity marks remodeled FR and S MNs destined to compensate for lost FF MNs before ultimately dying. Genetic ablation of OPN in SOD1(G93A) mice delayed disease onset but then accelerated disease progression. OPN induced MMP-9 up-regulation via αvβ3 integrin in ChAT-expressing Neuro2a cells, and also induced CD44-mediated astrocyte migration and microglial phagocytosis in a non-cell-autonomous manner. Our results demonstrate that OPN expressed by FR/S MNs is involved in the second-wave neurodegeneration by up-regulating MMP-9 through αvβ3 integrin in the mouse model of ALS. The differences in OPN/MMP-9 expression profiles in MN subsets partially explain the selective MN vulnerability in ALS.
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Affiliation(s)
- Yuta Morisaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Mamiko Niikura
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Mizuho Watanabe
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Kosuke Onishi
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Shogo Tanabe
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Yasuhiro Moriwaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Takashi Okuda
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
| | - Shinji Ohara
- Department of Neurology, Matsumoto Medical Center, Chushin-Matsumoto Hospital, Matsumoto 399-0021, Japan
| | - Shigeo Murayama
- Department of Neuropathology, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015, Japan
| | - Masaki Takao
- Department of Neuropathology, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015, Japan
| | - Sae Uchida
- Department of Autonomic Neuroscience, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015, Japan
| | - Koji Yamanaka
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya 464-8601, Japan
| | - Hidemi Misawa
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo 105-8512, Japan
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Dopamine Receptor Antagonists Enhance Proliferation and Neurogenesis of Midbrain Lmx1a-expressing Progenitors. Sci Rep 2016; 6:26448. [PMID: 27246266 PMCID: PMC4887985 DOI: 10.1038/srep26448] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 04/25/2016] [Indexed: 12/17/2022] Open
Abstract
Degeneration of dopamine neurons in the midbrain causes symptoms of the movement disorder, Parkinson disease. Dopamine neurons are generated from proliferating progenitor cells localized in the embryonic ventral midbrain. However, it remains unclear for how long cells with dopamine progenitor character are retained and if there is any potential for reactivation of such cells after cessation of normal dopamine neurogenesis. We show here that cells expressing Lmx1a and other progenitor markers remain in the midbrain aqueductal zone beyond the major dopamine neurogenic period. These cells express dopamine receptors, are located in regions heavily innervated by midbrain dopamine fibres and their proliferation can be stimulated by antagonizing dopamine receptors, ultimately leading to increased neurogenesis in vivo. Furthermore, treatment with dopamine receptor antagonists enhances neurogenesis in vitro, both from embryonic midbrain progenitors as well as from embryonic stem cells. Altogether our results indicate a potential for reactivation of resident midbrain cells with dopamine progenitor potential beyond the normal period of dopamine neurogenesis.
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48
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Differential neuronal vulnerability identifies IGF-2 as a protective factor in ALS. Sci Rep 2016; 6:25960. [PMID: 27180807 PMCID: PMC4867585 DOI: 10.1038/srep25960] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/25/2016] [Indexed: 12/13/2022] Open
Abstract
The fatal disease amyotrophic lateral sclerosis (ALS) is characterized by the loss of somatic motor neurons leading to muscle wasting and paralysis. However, motor neurons in the oculomotor nucleus, controlling eye movement, are for unknown reasons spared. We found that insulin-like growth factor 2 (IGF-2) was maintained in oculomotor neurons in ALS and thus could play a role in oculomotor resistance in this disease. We also showed that IGF-1 receptor (IGF-1R), which mediates survival pathways upon IGF binding, was highly expressed in oculomotor neurons and on extraocular muscle endplate. The addition of IGF-2 induced Akt phosphorylation, glycogen synthase kinase-3β phosphorylation and β-catenin levels while protecting ALS patient motor neurons. IGF-2 also rescued motor neurons derived from spinal muscular atrophy (SMA) patients from degeneration. Finally, AAV9::IGF-2 delivery to muscles of SOD1G93A ALS mice extended life-span by 10%, while preserving motor neurons and inducing motor axon regeneration. Thus, our studies demonstrate that oculomotor-specific expression can be utilized to identify candidates that protect vulnerable motor neurons from degeneration.
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Cacabelos D, Ayala V, Granado-Serrano AB, Jové M, Torres P, Boada J, Cabré R, Ramírez-Núñez O, Gonzalo H, Soler-Cantero A, Serrano JCE, Bellmunt MJ, Romero MP, Motilva MJ, Nonaka T, Hasegawa M, Ferrer I, Pamplona R, Portero-Otín M. Interplay between TDP-43 and docosahexaenoic acid-related processes in amyotrophic lateral sclerosis. Neurobiol Dis 2016; 88:148-60. [PMID: 26805387 DOI: 10.1016/j.nbd.2016.01.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Revised: 12/09/2015] [Accepted: 01/09/2016] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Docosahexaenoic acid (DHA), a key lipid in nervous system homeostasis, is depleted in the spinal cord of sporadic amyotrophic lateral sclerosis (sALS) patients. However, the basis for such loss was unknown. METHODS DHA synthetic machinery was evaluated in spinal cord samples from ALS patients and controls by immunohistochemistry and western blot. Further, lipid composition was measured in organotypic spinal cord cultures by gas chromatography and liquid chromatography coupled to mass spectrometry. In these samples, mitochondrial respiratory functions were measured by high resolution respirometry. Finally, Neuro2-A and stem cell-derived human neurons were used for evaluating mechanistic relationships between TDP-43 aggregation, oxidative stress and cellular changes in DHA-related proteins. RESULTS ALS is associated to changes in the spinal cord distribution of DHA synthesis enzymatic machinery comparing ten ALS cases and eight controls. We found increased levels of desaturases (ca 95% increase, p<0.001), but decreased amounts of DHA-related β-oxidation enzymes in ALS samples (40% decrease, p<0.05). Further, drebrin, a DHA-dependent synaptic protein, is depleted in spinal cord samples from ALS patients (around 40% loss, p<0.05). In contrast, chronic excitotoxicity in spinal cord increases DHA acid amount, with both enhanced concentrations of neuroprotective docosahexaenoic acid-derived resolvin D, and higher lipid peroxidation-derived molecules such as 8-iso-prostaglandin-F2-α (8-iso-PGF2α) levels. Since α-tocopherol improved mitochondrial respiratory function and motor neuron survival in these conditions, it is suggested that oxidative stress could boost motor neuron loss. Cell culture and metabolic flux experiments, showing enhanced expression of desaturases (FADS2) and β-oxidation enzymes after H2O2 challenge suggest that DHA production can be an initial response to oxidative stress, driven by TDP-43 aggregation and drebrin loss. Interestingly, these changes were dependent on cell type used, since human neurons exhibited losses of FADS2 and drebrin after oxidative stress. These features (drebrin loss and FADS2 alterations) were also produced by transfection by aggregation prone C-terminal fragments of TDP-43. CONCLUSIONS sALS is associated with tissue-specific DHA-dependent synthetic machinery alteration. Furthermore, excitotoxicity sinergizes with oxidative stress to increase DHA levels, which could act as a response over stress, involving the expression of DHA synthetic enzymes. Later on, this allostatic overload could exacerbate cell stress by contributing to TDP-43 aggregation. This, at its turn, could blunt this protective response, overall leading to DHA depletion and neuronal dysfunction.
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Affiliation(s)
- Daniel Cacabelos
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Victòria Ayala
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Ana Belén Granado-Serrano
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Mariona Jové
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Pascual Torres
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Jordi Boada
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Rosanna Cabré
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Omar Ramírez-Núñez
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Hugo Gonzalo
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Aranzazu Soler-Cantero
- Departament de Tecnologia d'Aliments, XaRTA-TPV, Escola Tècnica Superior d' Enginyeria Agrària, UdL, Avda Rovira Roure, 85, 25008 Lleida, Spain.
| | - José Carlos Enrique Serrano
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Maria Josep Bellmunt
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - María Paz Romero
- Departament de Tecnologia d'Aliments, XaRTA-TPV, Escola Tècnica Superior d' Enginyeria Agrària, UdL, Avda Rovira Roure, 85, 25008 Lleida, Spain.
| | - María José Motilva
- Departament de Tecnologia d'Aliments, XaRTA-TPV, Escola Tècnica Superior d' Enginyeria Agrària, UdL, Avda Rovira Roure, 85, 25008 Lleida, Spain.
| | - Takashi Nonaka
- Department of Neuropathology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, Setagaya-ku, Tokyo 156-8506, Japan.
| | - Masato Hasegawa
- Departament de Tecnologia d'Aliments, XaRTA-TPV, Escola Tècnica Superior d' Enginyeria Agrària, UdL, Avda Rovira Roure, 85, 25008 Lleida, Spain.
| | - Isidre Ferrer
- Institut de Neuropatologia, Hospital Universitari de Bellvitge - IDIBELL, Universitat de Barcelona, Spain; CIBERNED (Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas), Instituto Carlos III, Spanish Ministry of Health, Spain. L'Hospitalet de Llobregat, c/La Feixa Llarga, S/N 08908 Hospitalet de Llobregat, Barcelona, Spain.
| | - Reinald Pamplona
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
| | - Manuel Portero-Otín
- Departament de Medicina Experimental, Facultat de Medicina, IRBLLEIDA-UDL, Avda Rovira Roure, 44, 25008 Lleida, Spain.
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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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