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Stassart RM, Gomez-Sanchez JA, Lloyd AC. Schwann Cells as Orchestrators of Nerve Repair: Implications for Tissue Regeneration and Pathologies. Cold Spring Harb Perspect Biol 2024; 16:a041363. [PMID: 38199866 PMCID: PMC11146315 DOI: 10.1101/cshperspect.a041363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Peripheral nerves exist in a stable state in adulthood providing a rapid bidirectional signaling system to control tissue structure and function. However, following injury, peripheral nerves can regenerate much more effectively than those of the central nervous system (CNS). This multicellular process is coordinated by peripheral glia, in particular Schwann cells, which have multiple roles in stimulating and nurturing the regrowth of damaged axons back to their targets. Aside from the repair of damaged nerves themselves, nerve regenerative processes have been linked to the repair of other tissues and de novo innervation appears important in establishing an environment conducive for the development and spread of tumors. In contrast, defects in these processes are linked to neuropathies, aging, and pain. In this review, we focus on the role of peripheral glia, especially Schwann cells, in multiple aspects of nerve regeneration and discuss how these findings may be relevant for pathologies associated with these processes.
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Affiliation(s)
- Ruth M Stassart
- Paul-Flechsig-Institute of Neuropathology, University Clinic Leipzig, Leipzig 04103, Germany
| | - Jose A Gomez-Sanchez
- Instituto de Investigación Sanitaria y Biomédica de Alicante (ISABIAL), Alicante 03010, Spain
- Instituto de Neurociencias CSIC-UMH, Sant Joan de Alicante 03550, Spain
| | - Alison C Lloyd
- UCL Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, United Kingdom
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2
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Herbst R, Huijbers MG, Oury J, Burden SJ. Building, Breaking, and Repairing Neuromuscular Synapses. Cold Spring Harb Perspect Biol 2024; 16:a041490. [PMID: 38697654 PMCID: PMC11065174 DOI: 10.1101/cshperspect.a041490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2024]
Abstract
A coordinated and complex interplay of signals between motor neurons, skeletal muscle cells, and Schwann cells controls the formation and maintenance of neuromuscular synapses. Deficits in the signaling pathway for building synapses, caused by mutations in critical genes or autoantibodies against key proteins, are responsible for several neuromuscular diseases, which cause muscle weakness and fatigue. Here, we describe the role that four key genes, Agrin, Lrp4, MuSK, and Dok7, play in this signaling pathway, how an understanding of their mechanisms of action has led to an understanding of several neuromuscular diseases, and how this knowledge has contributed to emerging therapies for treating neuromuscular diseases.
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Affiliation(s)
- Ruth Herbst
- Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Maartje G Huijbers
- Department of Human Genetics, Leiden University Medical Centre LUMC, 2300 RC Leiden, the Netherlands
- Department of Neurology, Leiden University Medical Centre LUMC, 2333 ZA Leiden, the Netherlands
| | - Julien Oury
- Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, NYU School of Medicine, New York, New York 10016, USA
| | - Steven J Burden
- Neurology Department, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA
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3
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Kahn LC, Stonner MM, Dy CJ. Key Considerations for Nerve Transfer Rehabilitation After Surgical Reconstruction for Brachial Plexus and Peripheral Nerve Injuries. J Hand Surg Am 2024; 49:160-168. [PMID: 37999701 DOI: 10.1016/j.jhsa.2023.09.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 08/30/2023] [Accepted: 09/19/2023] [Indexed: 11/25/2023]
Abstract
Nerve transfer surgery is commonly used to treat patients with brachial plexus injuries. However, guidelines on postoperative rehabilitation are not clearly established. Nerve transfers require the patient to relearn how to recruit newly innervated muscle(s), which may not occur naturally or intuitively. Supervised therapy is a valuable resource to guide patients through their lengthy recovery (often >12 months) because target muscle strength is both obtained and functionally used in daily life. This article highlights 10 key principles that provide the foundation for rehabilitation following nerve transfer surgery after a brachial plexus injury. Due to the shortcomings of the current evidence base for nerve transfer rehabilitation, we have included our anecdotal experience to augment the existing literature. It is important to have a collaborative surgeon-therapist relationship to communicate regarding operative details, expected timelines for reinnervation, patient needs, and realistic expectations. We provide examples of how to tailor the exercise program to synergistically recruit both the donor and target muscle action, including how to appropriately advance exercises based on the current level of nerve return. We also discuss the role that fatigue plays in denervated muscle and how fatigue may affect the exercise demands placed on the target muscle during specific stages of recovery.
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Affiliation(s)
- Lorna C Kahn
- Milliken Hand Rehabilitation Center, Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO
| | - Macyn M Stonner
- Milliken Hand Rehabilitation Center, Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO
| | - Christopher J Dy
- Division of Hand and Microsurgery, Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, MO.
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4
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Perez-Gonzalez AP, Provost F, Rousse I, Piovesana R, Benzina O, Darabid H, Lamoureux B, Wang YS, Arbour D, Robitaille R. Functional adaptation of glial cells at neuromuscular junctions in response to injury. Glia 2022; 70:1605-1629. [PMID: 35474470 PMCID: PMC9543218 DOI: 10.1002/glia.24184] [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: 01/05/2021] [Revised: 04/14/2022] [Accepted: 04/18/2022] [Indexed: 12/04/2022]
Abstract
Synaptic elements from neuromuscular junctions (NMJs) undergo massive morphological and functional changes upon nerve injury. While morphological changes of NMJ‐associated glia in response to injury has been investigated, their functional properties remain elusive. Perisynaptic Schwann cells (PSCs), glial cells at the NMJ, are essential for NMJ maintenance and repair, and are involved in synaptic efficacy and plasticity. Importantly, these functions are regulated by PSCs ability to detect synaptic transmission through, notably, muscarinic (mAChRs) and purinergic receptors' activation. Using Ca2+ imaging and electrophysiological recordings of synaptic transmission at the mouse NMJ, we investigated PSC receptors activation following denervation and during reinnervation in adults and at denervated NMJs in an ALS mouse model (SOD1G37R). We observed reduced PSCs mAChR‐mediated Ca2+ responses at denervated and reinnervating NMJs. Importantly, PSC phenotypes during denervation and reinnervation were distinct than the one observed during NMJ maturation. At denervated NMJs, exogenous activation of mAChRs greatly diminished galectin‐3 expression, a glial marker of phagocytosis. PSCs Ca2+ responses at reinnervating NMJs did not correlate with the number of innervating axons or process extensions. Interestingly, we observed an extended period of reduced PSC mAChRs activation after the injury (up to 60 days), suggesting a glial memory of injury. PSCs associated with denervated NMJs in an ALS model (SOD1G37R mice) did not show any muscarinic adaptation, a phenotype incompatible with NMJ repair. Understanding functional mechanisms that underlie this glial response to injury may contribute to favor complete NMJ and motor recovery.
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Affiliation(s)
- Anna P Perez-Gonzalez
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Frédéric Provost
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Isabelle Rousse
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Roberta Piovesana
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Ouafa Benzina
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Houssam Darabid
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Benoit Lamoureux
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Yu Shi Wang
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Danielle Arbour
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
| | - Richard Robitaille
- Département de Neurosciences, Université de Montréal, Montréal, Québec, Canada.,Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada.,Centre Interdisciplinaire de Recherche sur le Cerveau et l'apprentissage, Montréal, Québec, Canada
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5
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Bączyk M, Manuel M, Roselli F, Zytnicki D. Diversity of Mammalian Motoneurons and Motor Units. ADVANCES IN NEUROBIOLOGY 2022; 28:131-150. [PMID: 36066824 DOI: 10.1007/978-3-031-07167-6_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Although they share the common function of controlling muscle fiber contraction, spinal motoneurons display a remarkable diversity. Alpha-motoneurons are the "final common pathway", which relay all the information from spinal and supraspinal centers and allow the organism to interact with the outside world by controlling the contraction of muscle fibers in the muscles. On the other hand, gamma-motoneurons are specialized motoneurons that do not generate force and instead specifically innervate muscle fibers inside muscle spindles, which are proprioceptive organs embedded in the muscles. Beta-motoneurons are hybrid motoneurons that innervate both extrafusal and intrafusal muscle fibers. Even among alpha-motoneurons, there exists an exquisite diversity in terms of motoneuron electrical and molecular properties, physiological and structural properties of their neuromuscular junctions, and molecular and contractile properties of the innervated muscle fibers. This diversity, across species, across muscles, and across muscle fibers in a given muscle, underlie the vast repertoire of movements that one individual can perform.
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Affiliation(s)
- Marcin Bączyk
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland
| | - Marin Manuel
- SPPIN - Saints-Pères Paris Institute for the Neurosciences, CNRS, Université de Paris, Paris, France.
| | - Francesco Roselli
- Department of Neurology, Ulm University, Ulm, Germany
- Institute of Anatomy and Cell Biology, Ulm University, Ulm, Germany
- German Center for Neurodegenerative Diseases (DZNE)-Ulm, Ulm, Germany
- Neurozentrum Ulm, Ulm, Germany
| | - Daniel Zytnicki
- SPPIN - Saints-Pères Paris Institute for the Neurosciences, CNRS, Université de Paris, Paris, France
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6
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Fuertes-Alvarez S, Izeta A. Terminal Schwann Cell Aging: Implications for Age-Associated Neuromuscular Dysfunction. Aging Dis 2021; 12:494-514. [PMID: 33815879 PMCID: PMC7990373 DOI: 10.14336/ad.2020.0708] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022] Open
Abstract
Action potential is transmitted to muscle fibers through specialized synaptic interfaces called neuromuscular junctions (NMJs). These structures are capped by terminal Schwann cells (tSCs), which play essential roles during formation and maintenance of the NMJ. tSCs are implicated in the correct communication between nerves and muscles, and in reinnervation upon injury. During aging, loss of muscle mass and strength (sarcopenia and dynapenia) are due, at least in part, to the progressive loss of contacts between muscle fibers and nerves. Despite the important role of tSCs in NMJ function, very little is known on their implication in the NMJ-aging process and in age-associated denervation. This review summarizes the current knowledge about the implication of tSCs in the age-associated degeneration of NMJs. We also speculate on the possible mechanisms underlying the observed phenotypes.
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Affiliation(s)
- Sandra Fuertes-Alvarez
- 1Biodonostia, Tissue Engineering Group, Paseo Dr. Begiristain, s/n, San Sebastian 20014, Spain
| | - Ander Izeta
- 1Biodonostia, Tissue Engineering Group, Paseo Dr. Begiristain, s/n, San Sebastian 20014, Spain.,2Tecnun-University of Navarra, School of Engineering, Department of Biomedical Engineering and Science, Paseo Mikeletegi, 48, San Sebastian 20009, Spain
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7
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Werner JM, Berggren J, Kim G, Loffredo K, Pascual M, Tiongson E, Seruya M. Recommendations for Therapy following Nerve Transfer for Children with Acute Flaccid Myelitis. Phys Occup Ther Pediatr 2021; 41:209-226. [PMID: 33016189 DOI: 10.1080/01942638.2020.1822981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
AIM To provide recommendations for pre- and post-operative occupational and physical therapy for children with acute flaccid myelitis (AFM). METHODS Writing panel members consisted of an interdisciplinary team of seven healthcare professionals specializing in the care of children with AFM. The panel reviewed background material on AFM, nerve transfer, and rehabilitation principles applied to pediatrics. Recommendations were prioritized if evidence was available. Where there was no known evidence to support a recommendation, this was noted. RECOMMENDATIONS Communication and coordination among interprofessional team members are vital to a comprehensive family-centered rehabilitation program. Surgical planning should include team preparation accounting for frequency, duration, and timing of treatment, as well as individual characteristics and developmental status of the child. Recommendations for pre-operative and six phases of post-operative therapy address assessment, strengthening, range of motion, orthoses, performance of functional activity, and support of the family. CONCLUSION Rehabilitation following nerve transfer in children with AFM requires interdisciplinary collaboration and a multisystem approach to assessment and treatment. As new evidence becomes available, recommendations may be revised or replaced accordingly.
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Affiliation(s)
- Julie M Werner
- Institute for Nursing and Interprofessional Research, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Division of Pediatric Rehabilitation Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Jamie Berggren
- Division of Pediatric Rehabilitation Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Gina Kim
- Division of Pediatric Rehabilitation Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Kimberly Loffredo
- Division of Pediatric Rehabilitation Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Marielle Pascual
- Division of Pediatric Rehabilitation Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Emmanuelle Tiongson
- Division of Neurology, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Department of Pediatrics, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - Mitchel Seruya
- Division of Plastic and Maxillofacial Surgery, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Plastic and Reconstructive Surgery, Keck School of Medicine of USC, Los Angeles, CA, USA
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8
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Gordon T. Peripheral Nerve Regeneration and Muscle Reinnervation. Int J Mol Sci 2020; 21:ijms21228652. [PMID: 33212795 PMCID: PMC7697710 DOI: 10.3390/ijms21228652] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/06/2020] [Accepted: 11/10/2020] [Indexed: 12/24/2022] Open
Abstract
Injured peripheral nerves but not central nerves have the capacity to regenerate and reinnervate their target organs. After the two most severe peripheral nerve injuries of six types, crush and transection injuries, nerve fibers distal to the injury site undergo Wallerian degeneration. The denervated Schwann cells (SCs) proliferate, elongate and line the endoneurial tubes to guide and support regenerating axons. The axons emerge from the stump of the viable nerve attached to the neuronal soma. The SCs downregulate myelin-associated genes and concurrently, upregulate growth-associated genes that include neurotrophic factors as do the injured neurons. However, the gene expression is transient and progressively fails to support axon regeneration within the SC-containing endoneurial tubes. Moreover, despite some preference of regenerating motor and sensory axons to “find” their appropriate pathways, the axons fail to enter their original endoneurial tubes and to reinnervate original target organs, obstacles to functional recovery that confront nerve surgeons. Several surgical manipulations in clinical use, including nerve and tendon transfers, the potential for brief low-frequency electrical stimulation proximal to nerve repair, and local FK506 application to accelerate axon outgrowth, are encouraging as is the continuing research to elucidate the molecular basis of nerve regeneration.
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Affiliation(s)
- Tessa Gordon
- Department of Surgery, University of Toronto, Division of Plastic Reconstructive Surgery, 06.9706 Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
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9
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Decreased Serum Levels of C-Terminal Agrin in Postmenopausal Women Following Resistance Training. J Aging Phys Act 2020; 28:73-80. [DOI: 10.1123/japa.2019-0066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/27/2019] [Accepted: 05/30/2019] [Indexed: 11/18/2022]
Abstract
Elevated circulating C-terminal agrin fragment (CAF) is a marker of neuromuscular junction degradation and sarcopenia. This study sought to determine if resistance training (RT) impacted the serum levels of CAF in perimenopausal (PERI-M) and postmenopausal (POST-M) women. A total of 35 women, either PERI-M or POST-M, participated in 10 weeks of RT. Body composition, muscle strength, and serum estradiol and CAF were determined before and after the RT. The data were analyzed with two-way analysis of variance (p ≤ .05). Upper body and lower body strength was significantly increased, by 81% and 73% and 86% and 79% for the PERI-M and POST-M participants, respectively; however, there were no significant changes in body composition. Estradiol was significantly less for the POST-M participants at pretraining compared with the PERI-M participants. CAF moderately increased by 22% for the PERI-M participants in response to RT, whereas it significantly decreased by 49% for the POST-M participants. Ten weeks of RT reduced the circulating CAF in the POST-M women and might play a role in attenuating degenerative neuromuscular junction changes.
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10
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Cercone M, Jarvis JC, Ducharme NG, Perkins J, Piercy RJ, Willand MP, Mitchell LM, Sledziona M, Soderholm L, Cheetham J. Functional electrical stimulation following nerve injury in a large animal model. Muscle Nerve 2019; 59:717-725. [PMID: 30815883 DOI: 10.1002/mus.26460] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 02/12/2019] [Accepted: 02/25/2019] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Controversy exists over the effects of functional electrical stimulation (FES) on reinnervation. We hypothesized that intramuscular FES would not delay reinnervation after recurrent laryngeal nerve (RLn) axonotmesis. METHODS RLn cryo-injury and electrode implantation in ipsilateral posterior cricoarytenoid muscle (PCA) were performed in horses. PCA was stimulated for 20 weeks in eight animals; seven served as controls. Reinnervation was monitored through muscle response to hypercapnia, electrical stimulation and exercise. Ultimately, muscle fiber type proportions and minimum fiber diameters, and RLn axon number and degree of myelination were determined. RESULTS Laryngeal function returned to normal in both groups within 22 weeks. FES improved muscle strength and geometry, and induced increased type I:II fiber proportion (p = 0.038) in the stimulated PCA. FES showed no deleterious effects on reinnervation. DISCUSSION Intramuscular electrical stimulation did not delay PCA reinnervation after axonotmesis. FES can represent a supportive treatment to promote laryngeal functional recovery after RLn injury. Muscle Nerve 59:717-725, 2019.
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Affiliation(s)
- Marta Cercone
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | | | - Norm G Ducharme
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Justin Perkins
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Sciences and Services, Royal Veterinary College, London, UK
| | - Richard J Piercy
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Sciences and Services, Royal Veterinary College, London, UK
| | | | - Lisa M Mitchell
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael Sledziona
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Leo Soderholm
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Jonathan Cheetham
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
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11
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Günter C, Delbeke J, Ortiz-Catalan M. Safety of long-term electrical peripheral nerve stimulation: review of the state of the art. J Neuroeng Rehabil 2019; 16:13. [PMID: 30658656 PMCID: PMC6339286 DOI: 10.1186/s12984-018-0474-8] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 12/11/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Electrical stimulation of peripheral nerves is used in a variety of applications such as restoring motor function in paralyzed limbs, and more recently, as means to provide intuitive sensory feedback in limb prostheses. However, literature on the safety requirements for stimulation is scarce, particularly for chronic applications. Some aspects of nerve interfacing such as the effect of stimulation parameters on electrochemical processes and charge limitations have been reviewed, but often only for applications in the central nervous system. This review focuses on the safety of electrical stimulation of peripheral nerve in humans. METHODS We analyzed early animal studies evaluating damage thresholds, as well as more recent investigations in humans. Safety requirements were divided into two main categories: passive and active safety. We made the distinction between short-term (< 30 days) and chronic (> 30 days) applications, as well as between electrode preservation (biostability) and body tissue healthy survival (harmlessness). In addition, transferability of experimental results between different tissues and species was considered. RESULTS At present, extraneural electrodes have shown superior long-term stability in comparison to intraneural electrodes. Safety limitations on pulse amplitude (and consequently, charge injection) are dependent on geometrical factors such as electrode placement, size, and proximity to the stimulated fiber. In contrast, other parameters such as stimulation frequency and percentage of effective stimulation time are more generally applicable. Currently, chronic stimulation at frequencies below 30 Hz and percentages of effective stimulation time below 50% is considered safe, but more precise data drawn from large databases are necessary. Unfortunately, stimulation protocols are not systematically documented in the literature, which limits the feasibility of meta-analysis and impedes the generalization of conclusions. We therefore propose a standardized list of parameters necessary to define electrical stimulation and allow future studies to contribute to meta-analyses. CONCLUSION The safety of chronic continuous peripheral nerve stimulation at frequencies higher than 30 Hz has yet to be documented. Precise parameter values leading to stimulation-induced depression of neuronal excitability (SIDNE) and neuronal damage, as well as the transition between the two, are still lacking. At present, neural damage mechanisms through electrical stimulation remain obscure.
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Affiliation(s)
- Clara Günter
- Biomechatronics and Neurorehabilitation Laboratory, Department of Electrical Engineering, Chalmers University of Technology, 41296, Gothenburg, Sweden
| | - Jean Delbeke
- LCEN3, Department of Neurology, Institute of Neuroscience, Ghent University, C. Heymanslaan, 10, 9000, Ghent, Belgium
| | - Max Ortiz-Catalan
- Biomechatronics and Neurorehabilitation Laboratory, Department of Electrical Engineering, Chalmers University of Technology, 41296, Gothenburg, Sweden. .,Integrum AB, Krokslätts Fabriker 50, 43137, Mölndal, Sweden.
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12
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Abstract
The schwann cells of the peripheral nervous system are indispensable for the formation, maintenance, and modulation of synapses over the life cycle. They not only recognize neuron-glia signaling molecules, but also secrete gliotransmitters. Through these processes, they regulate neuronal excitability and thus the release of neurotransmitters from the nerve terminal at the neuromuscular junction. Gliotransmitters strongly affect nerve communication, and their secretion is mainly triggered by synchronized Ca2+ signaling, implicating Ca2+ waves in synapse function. Reciprocally, neurotransmitters released during synaptic activity can evoke increases in intracellular Ca2+ levels. A reconsideration of the interplay between the two main types of cells in the nervous system is due, as the concept of nervous system activity comprising only neuron-neuron and neuron-muscle action has become untenable. A more precise understanding of the roles of schwann cells in nerve-muscle signaling is required.
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Affiliation(s)
- Sujin Hyung
- Department of Mechanical and Aerospace Engineering, Seoul National University, San 56-1, Shilim-dong, Gwanak-gu, Seoul, 08826, Korea
- BK21 Plus Transformative Training Program for Creative Mechanical and Aerospace Engineers, Seoul National University, San 56-1, Shilim-dong, Gwanak-gu, Seoul, 08826, Korea
| | - Kyuhwan Jung
- Graduate Program of Nano Science and Technology, Graduate School of Yonsei University, 50-1 Yonsei Ro, Seodaemun-gu, Seoul, 03722, Korea
| | - Sung-Rae Cho
- Graduate Program of Nano Science and Technology, Graduate School of Yonsei University, 50-1 Yonsei Ro, Seodaemun-gu, Seoul, 03722, Korea
- Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, 50-1 Yonsei Ro, Seodaemun-gu, Seoul, 03722, Korea
| | - Noo Li Jeon
- Department of Mechanical and Aerospace Engineering, Seoul National University, San 56-1, Shilim-dong, Gwanak-gu, Seoul, 08826, Korea
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13
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Tian J, Yu T, Xu Y, Pu S, Lv Y, Zhang X, DU D. Swimming Training Reduces Neuroma Pain by Regulating Neurotrophins. Med Sci Sports Exerc 2018; 50:54-61. [PMID: 28846565 PMCID: PMC5757647 DOI: 10.1249/mss.0000000000001411] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Introduction Neuroma formation after peripheral nerve transection leads to severe neuropathic pain in amputees. Previous studies suggested that physical exercise could bring beneficial effect on alleviating neuropathic pain. However, the effect of exercise on neuroma pain still remained unclear. In addition, long-term exercise can affect the expression of neurotrophins (NT), such as nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), which play key roles in nociceptor sensitization and nerve sprouting after nerve injury. Here, we investigated whether long-term swimming exercise could relieve neuroma pain by modulating NT expression. Methods We used a tibial neuroma transposition (TNT) rat model to mimic neuroma pain. After TNT surgery, rats performed swimming exercise for 5 wk. Neuroma pain and tactile sensitivities were detected using von Frey filaments. Immunofluorescence was applied to analyze neuroma formation. NGF and BDNF expressions in peripheral neuroma, dorsal root ganglion, and the spinal cord were measured using enzyme-linked immunosorbent assay and Western blotting. Results TNT led to neuroma formation, induced neuroma pain, and mechanical allodynia in hind paw. Five-week swimming exercise inhibited neuroma formation and relieved mechanical allodynia in the hind paw and neuroma pain in the lateral ankle. The analgesic effect lasted for at least 1 wk, even when the exercise ceased. TNT elevated the expressions of BDNF and NGF in peripheral neuroma, dorsal root ganglion, and the spinal cord to different extents. Swimming also decreased the elevation of NT expression. Conclusions Swimming exercise not only inhibits neuroma formation induced by nerve transection but also relieves pain behavior. These effects might be associated with the modulation of NT.
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Affiliation(s)
- Jinge Tian
- 1Pain Management Center, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, CHINA; 2Department of Anesthesiology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, CHINA; and 3Center for Translational Pain Medicine, Department of Anesthesiology, Duke University School of Medicine, Durham, NC
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Abstract
Sarcopenia is an age-related geriatric syndrome which is characterized by the gradual loss of muscle mass, muscle strength, and muscle quality. There are a lot of neurologic insults on sarcopenia at various levels from the brain to the neuromuscular junctions (NMJs) to generate a volitional task. Dopaminergic downregulation, inadequate motor programming and motor coordination impairment lead to decline of supraspinal drive. Motor unit reorganization and inflammatory changes in motor neuron decrease conduction velocity and amplitude of compound muscle action potential. Furthermore, NMJ remodeling and age related neurophysiological alterations may contribute to neuromuscular impairment. Sarcopenia is an age-associated, lifelong process which links to multiple etiological factors. Although not all the causes are completely understood, we suggest that compromised nervous system function may be one of the important contributors to the sarcopenia.
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Affiliation(s)
- Young Nam Kwon
- Department of Neurology, College of Medicine, Kyung Hee University, Seoul, Korea
| | - Sung Sang Yoon
- Department of Neurology, College of Medicine, Kyung Hee University, Seoul, Korea
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Pinheiro-Dardis CM, Erbereli BT, Gigo-Benato D, Castro PATS, Russo TL. Electrical stimulation delays reinnervation in denervated rat muscle. Muscle Nerve 2017; 56:E108-E118. [PMID: 28120411 DOI: 10.1002/mus.25589] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 01/09/2017] [Accepted: 01/18/2017] [Indexed: 02/05/2023]
Abstract
INTRODUCTION It is not clear if electrical stimulation (ES) can affect muscle reinnervation. This study aimed to verify if ES affects neuromuscular recovery after nerve crush injury in rats. METHODS Denervated muscles were electrically stimulated daily for 6 or 14 days. Neuromuscular performance and excitability, and muscle morphology were determined. Muscle trophism markers (atrogin-1, MuRF-1, and myoD), as well as neuromuscular junction (NMJ) organization (muscle-specific receptor tyrosine kinase [MuSK], cytoplasmic protein downstream of kinase-7 [Dok-7], nicotinic ACh receptor [nAChR], and neural cell adhesion molecule [N-CAM]) were assessed. RESULTS ES impaired neuromuscular recovery at day 14 postdenervation. Muscle hypoexcitability was accentuated by ES at 6 and 14 days postdenervation. Although ES reduced the accumulation of atrogin-1, MuRF1, and myoD mRNAs, it increased muscle atrophy. Gene expression of MuSK, Dok-7, nAChR, and the content of N-CAM protein were altered by ES. DISCUSSION ES can delay the reinnervation process by modulating factors related to NMJ stability and organization, and inducing dysfunction, hypoexcitability, and muscle atrophy. Muscle Nerve 56: E108-E118, 2017.
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Affiliation(s)
- Clara M Pinheiro-Dardis
- Fisioterapia Neurológica (LaFiN), Departamento de Fisioterapia, Universidade Federal de São Carlos (UFSCar), Rodovia Washington Luis, Km 235, C.P. 676 - CEP: 13565-905, São Carlos, SP, Brazil
| | - Bruna T Erbereli
- Fisioterapia Neurológica (LaFiN), Departamento de Fisioterapia, Universidade Federal de São Carlos (UFSCar), Rodovia Washington Luis, Km 235, C.P. 676 - CEP: 13565-905, São Carlos, SP, Brazil
| | - Davilene Gigo-Benato
- Fisioterapia Neurológica (LaFiN), Departamento de Fisioterapia, Universidade Federal de São Carlos (UFSCar), Rodovia Washington Luis, Km 235, C.P. 676 - CEP: 13565-905, São Carlos, SP, Brazil
| | - Paula A T S Castro
- Laboratory of Muscle Plasticity, DFisio, UFSCar, São Carlos, São Paulo, Brazil
| | - Thiago L Russo
- Fisioterapia Neurológica (LaFiN), Departamento de Fisioterapia, Universidade Federal de São Carlos (UFSCar), Rodovia Washington Luis, Km 235, C.P. 676 - CEP: 13565-905, São Carlos, SP, Brazil
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Gordon T, Borschel GH. The use of the rat as a model for studying peripheral nerve regeneration and sprouting after complete and partial nerve injuries. Exp Neurol 2017; 287:331-347. [DOI: 10.1016/j.expneurol.2016.01.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 02/06/2023]
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17
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Arbat-Plana A, Cobianchi S, Herrando-Grabulosa M, Navarro X, Udina E. Endogenous modulation of TrkB signaling by treadmill exercise after peripheral nerve injury. Neuroscience 2017; 340:188-200. [DOI: 10.1016/j.neuroscience.2016.10.057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 10/18/2016] [Accepted: 10/22/2016] [Indexed: 12/20/2022]
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Cobianchi S, Arbat-Plana A, López-Álvarez VM, Navarro X. Neuroprotective Effects of Exercise Treatments After Injury: The Dual Role of Neurotrophic Factors. Curr Neuropharmacol 2017; 15:495-518. [PMID: 27026050 PMCID: PMC5543672 DOI: 10.2174/1570159x14666160330105132] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 02/19/2016] [Accepted: 03/03/2016] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Shared connections between physical activity and neuroprotection have been studied for decades, but the mechanisms underlying this effect of specific exercise were only recently brought to light. Several evidences suggest that physical activity may be a reasonable and beneficial method to improve functional recovery in both peripheral and central nerve injuries and to delay functional decay in neurodegenerative diseases. In addition to improving cardiac and immune functions, physical activity may represent a multifunctional approach not only to improve cardiocirculatory and immune functions, but potentially modulating trophic factors signaling and, in turn, neuronal function and structure at times that may be critical for neurodegeneration and regeneration. METHODS Research content related to the effects of physical activity and specific exercise programs in normal and injured nervous system have been reviewed. RESULTS Sustained exercise, particularly if applied at moderate intensity and early after injury, exerts anti-inflammatory and pro-regenerative effects, and may boost cognitive and motor functions in aging and neurological disorders. However, newest studies show that exercise modalities can differently affect the production and function of brain-derived neurotrophic factor and other neurotrophins involved in the generation of neuropathic conditions. These findings suggest the possibility that new exercise strategies can be directed to nerve injuries with therapeutical benefits. CONCLUSION Considering the growing burden of illness worldwide, understanding of how modulation of neurotrophic factors contributes to exercise-induced neuroprotection and regeneration after peripheral nerve and spinal cord injuries is a relevant topic for research, and represents the beginning of a new non-pharmacological therapeutic approach for better rehabilitation of neural disorders.
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Affiliation(s)
- Stefano Cobianchi
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Ariadna Arbat-Plana
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Víctor M. López-Álvarez
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Xavier Navarro
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autonoma de Barcelona, Bellaterra, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
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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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Chao X, Xu L, Shang H, Han Y, Cai J, Li J, Wang H, Fan Z. The injury of marginal mandibular branch unexpectedly promotes the repair of buccal branch of facial nerve in a rat model. Acta Otolaryngol 2016; 136:956-63. [PMID: 27093225 DOI: 10.3109/00016489.2016.1169318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSIONS The results indicate that the injury of the marginal mandibular branch improved the recovery of the buccal branch in a rat model. OBJECTIVE The aim of this study was to investigate whether the injury or intactness of the marginal mandibular branch affects the regeneration of the facial nerve buccal branch in a rat model. METHODS This experiment was conducted on 30 adult rats, which were randomly and equally divided into two groups. The buccal branch of the facial nerve was transected and reconstructed, with the marginal mandibular branch damaged (group A) or intact (group B). The vibrissae movement of rats was assessed since the 4th week after operation. At the 8th and 12th week, compound muscle action potentials (CMAPs) and morphological changes of injured buccal branches were evaluated. RESULTS After the operation, vibrissae movement of rats was eliminated in group A, but it was similar to the health side in group B. CMAPs were recorded from regenerated buccal branches in group A since the 8th week, but no CMAPs could be recorded in group B at each time point. Additionally, the diameter of nerve fibers, the thickness of myelin sheath, and the density of regenerated fibers in group A were significantly larger than those in group B (p < 0.05).
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Affiliation(s)
- Xiuhua Chao
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
- b Shandong Institute of Otolaryngology, Shandong Provincial Key Laboratory of Otology , Jinan , PR China
| | - Lei Xu
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
| | - Haiqiong Shang
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
- b Shandong Institute of Otolaryngology, Shandong Provincial Key Laboratory of Otology , Jinan , PR China
| | - Yuechen Han
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
| | - Jing Cai
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
| | - Jianfeng Li
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
- b Shandong Institute of Otolaryngology, Shandong Provincial Key Laboratory of Otology , Jinan , PR China
| | - Haibo Wang
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
- b Shandong Institute of Otolaryngology, Shandong Provincial Key Laboratory of Otology , Jinan , PR China
| | - Zhaomin Fan
- a Department of Otolaryngology Head and Neck Surgery , Shandong Provincial Hospital Affiliated to Shandong University , Jinan , PR China
- b Shandong Institute of Otolaryngology, Shandong Provincial Key Laboratory of Otology , Jinan , PR China
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Willand MP, Rosa E, Michalski B, Zhang JJ, Gordon T, Fahnestock M, Borschel GH. Electrical muscle stimulation elevates intramuscular BDNF and GDNF mRNA following peripheral nerve injury and repair in rats. Neuroscience 2016; 334:93-104. [PMID: 27476437 DOI: 10.1016/j.neuroscience.2016.07.040] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 07/21/2016] [Accepted: 07/23/2016] [Indexed: 10/21/2022]
Abstract
Despite advances in surgery, patients with nerve injuries frequently have functional deficits. We previously demonstrated in a rat model that daily electrical muscle stimulation (EMS) following peripheral nerve injury and repair enhances reinnervation, detectable as early as two weeks post-injury. In this study, we explain the enhanced early reinnervation observed with electrical stimulation. In two groups of rats, the tibial nerve was transected and immediately repaired. Gastrocnemius muscles were implanted with intramuscular electrodes for sham or muscle stimulation. Muscles were stimulated daily, eliciting 600 contractions for one hour/day, repeated five days per week. Sixteen days following nerve injury, muscles were assessed for functional reinnervation by motor unit number estimation methods using electromyographic recording. In a separate cohort of rats, surgical and electrical stimulation procedures were identical but muscles and distal nerve stumps were harvested for molecular analysis. We observed that stimulated muscles had significantly higher motor unit number counts. Intramuscular levels of brain-derived and glial cell line-derived neurotrophic factor (BDNF and GDNF) mRNA were significantly upregulated in muscles that underwent daily electrical stimulation compared to those without stimulation. The corresponding levels of trophic factor mRNA within the distal stump were not different from one another, indicating that the intramuscular electrical stimulus does not modulate Schwann cell-derived trophic factor transcription. Stimulation over a three-month period maintained elevated muscle-derived GDNF but not BDNF mRNA. In conclusion, EMS elevates intramuscular trophic factor mRNA levels which may explain how EMS enhances neural regeneration following nerve injury.
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Affiliation(s)
- Michael P Willand
- Department of Surgery, Division of Plastic Reconstructive Surgery, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada.
| | - Elyse Rosa
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Bernadeta Michalski
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Jennifer J Zhang
- Department of Surgery, Division of Plastic Reconstructive Surgery, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; SickKids Research Institute Program in Neuroscience and Mental Health, Toronto, ON, Canada
| | - Tessa Gordon
- Department of Surgery, Division of Plastic Reconstructive Surgery, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Margaret Fahnestock
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Gregory H Borschel
- Department of Surgery, Division of Plastic Reconstructive Surgery, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada; SickKids Research Institute Program in Neuroscience and Mental Health, Toronto, ON, Canada; University of Toronto Division of Plastic and Reconstructive Surgery, Toronto, ON, Canada
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22
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Mancuso R, Martínez-Muriana A, Leiva T, Gregorio D, Ariza L, Morell M, Esteban-Pérez J, García-Redondo A, Calvo AC, Atencia-Cibreiro G, Corfas G, Osta R, Bosch A, Navarro X. Neuregulin-1 promotes functional improvement by enhancing collateral sprouting in SOD1(G93A) ALS mice and after partial muscle denervation. Neurobiol Dis 2016; 95:168-78. [PMID: 27461051 DOI: 10.1016/j.nbd.2016.07.023] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 06/23/2016] [Accepted: 07/22/2016] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive degeneration of motoneurons, which is preceded by loss of neuromuscular connections in a "dying back" process. Neuregulin-1 (Nrg1) is a neurotrophic factor essential for the development and maintenance of neuromuscular junctions, and Nrg1 receptor ErbB4 loss-of-function mutations have been reported as causative for ALS. Our main goal was to investigate the role of Nrg1 type I (Nrg1-I) in SOD1(G93A) mice muscles. We overexpressed Nrg1-I by means of an adeno-associated viral (AAV) vector, and investigated its effect by means of neurophysiological techniques assessing neuromuscular function, as well as molecular approaches (RT-PCR, western blot, immunohistochemistry, ELISA) to determine the mechanisms underlying Nrg1-I action. AAV-Nrg1-I intramuscular administration promoted motor axon collateral sprouting by acting on terminal Schwann cells, preventing denervation of the injected muscles through Akt and ERK1/2 pathways. We further used a model of muscle partial denervation by transecting the L4 spinal nerve. AAV-Nrg1-I intramuscular injection enhanced muscle reinnervation by collateral sprouting, whereas administration of lapatinib (ErbB receptor inhibitor) completely blocked it. We demonstrated that Nrg1-I plays a crucial role in the collateral reinnervation process, opening a new window for developing novel ALS therapies for functional recovery rather than preservation.
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Affiliation(s)
- Renzo Mancuso
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain; Biological Sciences, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Anna Martínez-Muriana
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Tatiana Leiva
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - David Gregorio
- Center of Animal Biotechnology and Gene Therapy and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Lorena Ariza
- Center of Animal Biotechnology and Gene Therapy and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Marta Morell
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain
| | - Jesús Esteban-Pérez
- Unidad de ELA, Servicio de Neurología, Instituto de Investigación Biomédica, Hospital 12 de Octubre "i+12", Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Alberto García-Redondo
- Unidad de ELA, Servicio de Neurología, Instituto de Investigación Biomédica, Hospital 12 de Octubre "i+12", Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Ana C Calvo
- Department of Otolaryngology - Head and Neck Surgery, Kresgae Hearing Research Institute, University of Michigan, Michigan, US
| | - Gabriela Atencia-Cibreiro
- Unidad de ELA, Servicio de Neurología, Instituto de Investigación Biomédica, Hospital 12 de Octubre "i+12", Madrid, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Gabriel Corfas
- Department of Otolaryngology - Head and Neck Surgery, Kresgae Hearing Research Institute, University of Michigan, Michigan, US
| | - Rosario Osta
- Laboratorio de Genética y Bioquímica (LAGENBIO), Facultad de Veterinaria, Instituto Agroalimentario de Aragón (IA2), Instituto de Investigación Sanitaria Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Assumpció Bosch
- Center of Animal Biotechnology and Gene Therapy and Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Xavier Navarro
- Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Bellaterra, Spain.
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Arai K, Takahashi K, Yasuda A, Kanno N, Kohara Y, Michishita M, Harada Y, Hara Y. Denervation-Associated Change in the Palatinus and Levator Veli Palatini Muscles of Dogs with Elongated Soft Palate. J Comp Pathol 2016; 155:199-206. [PMID: 27426002 DOI: 10.1016/j.jcpa.2016.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/08/2016] [Accepted: 06/21/2016] [Indexed: 11/28/2022]
Abstract
Muscle lesions and decreased numbers of peripheral nerve branches have been reported in the soft palates of dogs presenting with brachycephalic airway obstruction syndrome (BAOS). Myosin adenosine triphosphatase staining was employed to investigate whether muscle lesions in the elongated soft palate (ESP) of dogs with BAOS reflect the presence of denervation. Soft palates were collected from nine brachycephalic dogs during surgical intervention for BAOS and from five healthy beagle dogs as controls. In the control soft palates, myofibres with relatively uniform diameters and a random mosaic pattern of type I and II myofibres were observed in the palatinus muscle (PM), while almost all of the myofibres in the levator veli palatini muscle (LVPM) were of type II. In the ESPs, small group atrophy, large group atrophy and angular-shaped atrophy were observed in myofibres of the PM and rarely in the LVPM. Fibre type grouping and an increase in type IIC myofibres were found only in the PM. Morphometric analysis of ESPs revealed a significant increase in the number of type I and II myofibres in the PM showing atrophy or hypertrophy compared with controls. A significant increase in atrophic type II myofibres was found in the LVPM of affected dogs. Myopathy consistent with denervation was observed in the PM, but rarely in the LVPM, of ESP specimens. The results suggest that the myopathy seen in dogs with ESP may partly reflect atrophy of myofibres resulting from damage to peripheral nerve branches, with subsequent reinnervation of myofibres.
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Affiliation(s)
- K Arai
- Laboratory of Veterinary Surgery, Japan; Laboratory of Veterinary Pathology, Japan.
| | | | | | - N Kanno
- Laboratory of Veterinary Surgery, Japan
| | - Y Kohara
- Laboratory of Veterinary Anatomy, Nippon Veterinary and Life Science University, 1-7-1 Kyounan-cho, Musashino, Tokyo, Japan
| | | | - Y Harada
- Laboratory of Veterinary Surgery, Japan
| | - Y Hara
- Laboratory of Veterinary Surgery, Japan
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Gordon T. Nerve Regeneration: Understanding Biology and Its Influence on Return of Function After Nerve Transfers. Hand Clin 2016; 32:103-17. [PMID: 27094884 DOI: 10.1016/j.hcl.2015.12.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Poor functional outcomes are frequent after peripheral nerve injuries despite the regenerative support of Schwann cells. Motoneurons and, to a lesser extent, sensory neurons survive the injuries but outgrowth of axons across the injury site is slow. The neuronal regenerative capacity and the support of regenerating axons by the chronically denervated Schwann cells progressively declines with time and distance of the injury from the denervated targets. Strategies, including brief low-frequency electrical stimulation that accelerates target reinnervation and functional recovery, and the insertion of cross-bridges between a donor nerve and a recipient denervated nerve stump, are effective in promoting functional outcomes after complete and incomplete injuries.
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Affiliation(s)
- Tessa Gordon
- Division of Plastic Reconstructive Surgery, Department of Surgery, 06.9706 Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, 686 Bay Street, Toronto, Ontario M5G 0A4, Canada.
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Papalia I, Magaudda L, Righi M, Ronchi G, Viano N, Geuna S, Colonna MR. Epineurial Window Is More Efficient in Attracting Axons than Simple Coaptation in a Sutureless (Cyanoacrylate-Bound) Model of End-to-Side Nerve Repair in the Rat Upper Limb: Functional and Morphometric Evidences and Review of the Literature. PLoS One 2016; 11:e0148443. [PMID: 26872263 PMCID: PMC4752340 DOI: 10.1371/journal.pone.0148443] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 01/18/2016] [Indexed: 12/27/2022] Open
Abstract
End-to-side nerve coaptation brings regenerating axons from the donor to the recipient nerve. Several techniques have been used to perform coaptation: microsurgical sutures with and without opening a window into the epi(peri)neurial connective tissue; among these, window techniques have been proven more effective in inducing axonal regeneration. The authors developed a sutureless model of end-to-side coaptation in the rat upper limb. In 19 adult Wistar rats, the median and the ulnar nerves of the left arm were approached from the axillary region, the median nerve transected and the proximal stump sutured to the pectoral muscle to prevent regeneration. Animals were then randomly divided in two experimental groups (7 animals each, 5 animals acting as control): Group 1: the distal stump of the transected median nerve was fixed to the ulnar nerve by applying cyanoacrylate solution; Group 2: a small epineurial window was opened into the epineurium of the ulnar nerve, caring to avoid damage to the nerve fibres; the distal stump of the transected median nerve was then fixed to the ulnar nerve by applying cyanoacrylate solution. The grasping test for functional evaluation was repeated every 10-11 weeks starting from week-15, up to the sacrifice (week 36). At week 36, the animals were sacrificed and the regenerated nerves harvested and processed for morphological investigations (high-resolution light microscopy as well as stereological and morphometrical analysis). This study shows that a) cyanoacrylate in end-to-side coaptation produces scarless axon regeneration without toxic effects; b) axonal regeneration and myelination occur even without opening an epineurial window, but c) the window is related to a larger number of regenerating fibres, especially myelinated and mature, and better functional outcomes.
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Affiliation(s)
- Igor Papalia
- Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Ludovico Magaudda
- Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Maria Righi
- Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Giulia Ronchi
- Department of Clinical and Biological Sciences, University of Torino, Orbassano (Torino), Italy
- Neuroscience Institute of the “Cavalieri Ottolenghi” Foundation (NICO), University of Torino, Orbassano (Torino), Italy
| | - Nicoletta Viano
- Department of Clinical and Biological Sciences, University of Torino, Orbassano (Torino), Italy
| | - Stefano Geuna
- Department of Clinical and Biological Sciences, University of Torino, Orbassano (Torino), Italy
- Neuroscience Institute of the “Cavalieri Ottolenghi” Foundation (NICO), University of Torino, Orbassano (Torino), Italy
- * E-mail:
| | - Michele Rosario Colonna
- Department of Experimental and Clinical Surgical and Medical Specialties, University of Messina, Messina, Italy
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Early increasing-intensity treadmill exercise reduces neuropathic pain by preventing nociceptor collateral sprouting and disruption of chloride cotransporters homeostasis after peripheral nerve injury. Pain 2015; 156:1812-1825. [DOI: 10.1097/j.pain.0000000000000268] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Ko CP, Robitaille R. Perisynaptic Schwann Cells at the Neuromuscular Synapse: Adaptable, Multitasking Glial Cells. Cold Spring Harb Perspect Biol 2015; 7:a020503. [PMID: 26430218 PMCID: PMC4588062 DOI: 10.1101/cshperspect.a020503] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The neuromuscular junction (NMJ) is engineered to be a highly reliable synapse to carry the control of the motor commands of the nervous system over the muscles. Its development, organization, and synaptic properties are highly structured and regulated to support such reliability and efficacy. Yet, the NMJ is also highly plastic, able to react to injury and adapt to changes. This balance between structural stability and synaptic efficacy on one hand and structural plasticity and repair on another hand is made possible by the intricate regulation of perisynaptic Schwann cells, glial cells at this synapse. They regulate both the efficacy and structural plasticity of the NMJ in a dynamic, bidirectional manner owing to their ability to decode synaptic transmission and by their interactions via trophic-related factors.
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Affiliation(s)
- Chien-Ping Ko
- Section of Neurobiology, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-2520
| | - Richard Robitaille
- Département de Neurosciences, Université de Montréal, Montréal, Québec H3C 3J7, Canada Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec H3C 3J7, Canada
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Akdeniz ZD, Bayramiçli M, Ateş F, Özkan N, Yucesoy CA, Ercan F. The role of botulinum toxin type a-induced motor endplates after peripheral nerve repair. Muscle Nerve 2015; 52:412-8. [PMID: 25640922 DOI: 10.1002/mus.24555] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 11/19/2014] [Accepted: 12/17/2014] [Indexed: 11/08/2022]
Abstract
INTRODUCTION The aim of this study was to test the hypothesis that the increased number of new motor endplates induced by botulinum toxin type A (BTX-A) injection before nerve injury would be reinnervated after nerve repair, resulting in greater force generation. METHODS Thirty male Wistar rats were divided randomly into 3 groups: (1) controls; (2) a group with saline solution injection; and (3) a group with BTX-A injection into gastrocnemius muscle (BTX group). Thirty-six days after the injections the left sciatic nerve was divided and coapted in all groups. Eight weeks later, muscle forces were measured, and histological samples were collected. RESULTS No differences in the number of innervated endplates were found between the groups, but the number of denervated endplates was higher in the BTX group, as was the muscle tissue degeneration score. The BTX group showed distal muscle force measurements of up to 25.8% less compared with the control group. CONCLUSION Although BTX-A injection increases the number of motor endplates, they are not functional.
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Affiliation(s)
- Zeynep D Akdeniz
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Marmara University Faculty of Medicine, Fevzi Çakmak Mah, Mimar Sinan Cadde No: 41 Pendik, İstanbul, Turkey.,Department of Plastic, Reconstructive and Aesthetic Surgery, Adana Numune Training and Research Hospital, Adana, Turkey
| | - Mehmet Bayramiçli
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Marmara University Faculty of Medicine, Fevzi Çakmak Mah, Mimar Sinan Cadde No: 41 Pendik, İstanbul, Turkey
| | - Filiz Ateş
- Biomechanical Engineering Institute, Boğaziçi University, İstanbul, Turkey.,EA 4334 "Motricité, Interactions, Performance," Faculty of Sports Sciences, University of Nantes, Nantes, France
| | - Naziye Özkan
- Department of Histology and Embryology, Marmara University Faculty of Medicine, İstanbul, Turkey
| | - Can A Yucesoy
- Biomechanical Engineering Institute, Boğaziçi University, İstanbul, Turkey
| | - Feriha Ercan
- Department of Histology and Embryology, Marmara University Faculty of Medicine, İstanbul, Turkey
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Willand MP, Chiang CD, Zhang JJ, Kemp SWP, Borschel GH, Gordon T. Daily Electrical Muscle Stimulation Enhances Functional Recovery Following Nerve Transection and Repair in Rats. Neurorehabil Neural Repair 2014; 29:690-700. [DOI: 10.1177/1545968314562117] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background. Incomplete recovery following surgical reconstruction of damaged peripheral nerves is common. Electrical muscle stimulation (EMS) to improve functional outcomes has not been effective in previous studies. Objective. To evaluate the efficacy of a new, clinically translatable EMS paradigm over a 3-month period following nerve transection and immediate repair. Methods. Rats were divided into 6 groups based on treatment (EMS or no treatment) and duration (1, 2, or 3 months). A tibial nerve transection injury was immediately repaired with 2 epineurial sutures. The right gastrocnemius muscle in all rats was implanted with intramuscular electrodes. In the EMS group, the muscle was electrically stimulated with 600 contractions per day, 5 days a week. Terminal measurements were made after 1, 2, or 3 months. Rats in the 3-month group were assessed weekly using skilled and overground locomotion tests. Neuromuscular junction reinnervation patterns were also examined. Results. Muscles that received daily EMS had significantly greater numbers of reinnervated motor units with smaller average motor unit sizes. The majority of muscle endplates were reinnervated by a single axon arising from a nerve trunk with significantly fewer numbers of terminal sprouts in the EMS group, the numbers being small. Muscle mass and force were unchanged but EMS improved behavioral outcomes. Conclusions. Our results demonstrated that EMS using a moderate stimulation paradigm immediately following nerve transection and repair enhances electrophysiological and behavioral recovery.
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Affiliation(s)
| | | | | | | | | | - Tessa Gordon
- The Hospital for Sick Children, Toronto, Ontario, Canada
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Moloney EB, de Winter F, Verhaagen J. ALS as a distal axonopathy: molecular mechanisms affecting neuromuscular junction stability in the presymptomatic stages of the disease. Front Neurosci 2014; 8:252. [PMID: 25177267 PMCID: PMC4132373 DOI: 10.3389/fnins.2014.00252] [Citation(s) in RCA: 217] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 07/29/2014] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is being redefined as a distal axonopathy, in that many molecular changes influencing motor neuron degeneration occur at the neuromuscular junction (NMJ) at very early stages of the disease prior to symptom onset. A huge variety of genetic and environmental causes have been associated with ALS, and interestingly, although the cause of the disease can differ, both sporadic and familial forms of ALS show a remarkable similarity in terms of disease progression and clinical manifestation. The NMJ is a highly specialized synapse, allowing for controlled signaling between muscle and nerve necessary for skeletal muscle function. In this review we will evaluate the clinical, animal experimental and cellular/molecular evidence that supports the idea of ALS as a distal axonopathy. We will discuss the early molecular mechanisms that occur at the NMJ, which alter the functional abilities of the NMJ. Specifically, we focus on the role of axon guidance molecules on the stability of the cytoskeleton and how these molecules may directly influence the cells of the NMJ in a way that may initiate or facilitate the dismantling of the neuromuscular synapse in the presymptomatic stages of ALS.
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Affiliation(s)
- Elizabeth B. Moloney
- Department of Regeneration of Sensorimotor Systems, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and ScienceAmsterdam, Netherlands
| | - Fred de Winter
- Department of Regeneration of Sensorimotor Systems, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and ScienceAmsterdam, Netherlands
- Department of Neurosurgery, Leiden University Medical CentreLeiden, Netherlands
| | - Joost Verhaagen
- Department of Regeneration of Sensorimotor Systems, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and ScienceAmsterdam, Netherlands
- Centre for Neurogenomics and Cognitive Research, Vrije Universiteit AmsterdamAmsterdam, Netherlands
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Jiang Z, Zhu Y, Xu L, Xu JG, Gu YD. Functional Changes in Motor Endplates of the Target Muscle after Amputation of the C7 Nerve Root. NEUROPHYSIOLOGY+ 2014. [DOI: 10.1007/s11062-014-9406-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Klimaschewski L, Hausott B, Angelov DN. The pros and cons of growth factors and cytokines in peripheral axon regeneration. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2013; 108:137-71. [PMID: 24083434 DOI: 10.1016/b978-0-12-410499-0.00006-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Injury to a peripheral nerve induces a complex cellular and molecular response required for successful axon regeneration. Proliferating Schwann cells organize into chains of cells bridging the lesion site, which is invaded by macrophages. Approximately half of the injured neuron population sends out axons that enter the glial guidance channels in response to secreted neurotrophic factors and neuropoietic cytokines. These lesion-associated polypeptides create an environment that is highly supportive for axon regrowth, particularly after acute injury, and ensure that the vast majority of regenerating axons are directed toward the distal nerve stump. Unfortunately, most neurotrophic factors and neuropoietic cytokines are also strong stimulators of axonal sprouting. Although some of the axonal branches will withdraw at later stages, the sprouting effect contributes to the misdirection of reinnervation that results in the lack of functional recovery observed in many patients with peripheral nerve injuries. Here, we critically review the role of neuronal growth factors and cytokines during axon regeneration in the peripheral nervous system. Their differential effects on axon elongation and sprouting were elucidated in various studies on intraneuronal signaling mechanisms following nerve lesion. The present data define a goal for future therapeutic strategies, namely, to selectively stimulate a Ras/Raf/ERK-mediated axon elongation program over an intrinsic PI3K-dependent axonal sprouting program in lesioned motor and sensory neurons. Instead of modulating growth factor or cytokine levels at the lesion site, targeting specific intraneuronal molecules, such as the negative feedback inhibitors of ERK signaling, has been shown to promote long-distance regeneration while avoiding sprouting of regenerating axons until they have reached their target areas.
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Affiliation(s)
- Lars Klimaschewski
- Division of Neuroanatomy, Department of Anatomy and Histology, Innsbruck Medical University, Innsbruck, Austria
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Cobianchi S, Casals-Diaz L, Jaramillo J, Navarro X. Differential effects of activity dependent treatments on axonal regeneration and neuropathic pain after peripheral nerve injury. Exp Neurol 2012. [PMID: 23201096 DOI: 10.1016/j.expneurol.2012.11.023] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Activity treatments are useful strategies to increase axonal regeneration and functional recovery after nerve lesions. They are thought to benefit neuropathy by enhancing neurotrophic factor expression. Nevertheless the effects on sensory function are still unclear. Since neurotrophic factors also play a fundamental role in peripheral and central sensitization, we studied the effects of acute electrical stimulation and early treadmill exercise on nerve regeneration and on neuropathic pain, and the relation with the expression of neurotrophins. After sciatic nerve section and suture repair, rats were subjected to electrical stimulation (ES) for 4h after injury, forced treadmill running (TR) for 5 days, or both treatments combined. Sciatic nerve section induced hyperalgesia in the medial area of the plantar skin in the injured paw. TR and ES differently but positively reduced adjacent neuropathic pain before and after sciatic reinnervation. ES enhanced motor and sensory reinnervation, and combination with TR induced strong agonistic effects in relieving pain. The differential effects of these activity treatments were related to changes in neurotrophic factor mRNA levels in sensory and motor neurons. ES speeded up expression of BDNF and GDNF in DRG, and of BDNF and NT3 in the ventral horn. TR reduced the levels of pro-nociceptive factors such as BDNF, NGF and GDNF in DRG. Combination of ES and TR induced intermediate levels suggesting an optimal balancing of treatment effects.
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Affiliation(s)
- Stefano Cobianchi
- Group of Neuroplasticity and Regeneration, Institute of Neurosciences and Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain
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Neuron-glia interactions: the roles of Schwann cells in neuromuscular synapse formation and function. Biosci Rep 2012; 31:295-302. [PMID: 21517783 DOI: 10.1042/bsr20100107] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The NMJ (neuromuscular junction) serves as the ultimate output of the motor neurons. The NMJ is composed of a presynaptic nerve terminal, a postsynaptic muscle and perisynaptic glial cells. Emerging evidence has also demonstrated an existence of perisynaptic fibroblast-like cells at the NMJ. In this review, we discuss the importance of Schwann cells, the glial component of the NMJ, in the formation and function of the NMJ. During development, Schwann cells are closely associated with presynaptic nerve terminals and are required for the maintenance of the developing NMJ. After the establishment of the NMJ, Schwann cells actively modulate synaptic activity. Schwann cells also play critical roles in regeneration of the NMJ after nerve injury. Thus, Schwann cells are indispensable for formation and function of the NMJ. Further examination of the interplay among Schwann cells, the nerve and the muscle will provide insights into a better understanding of mechanisms underlying neuromuscular synapse formation and function.
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Effects of activity-dependent strategies on regeneration and plasticity after peripheral nerve injuries. Ann Anat 2011; 193:347-53. [DOI: 10.1016/j.aanat.2011.02.012] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 02/14/2011] [Accepted: 02/24/2011] [Indexed: 12/27/2022]
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36
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Outcome measures of peripheral nerve regeneration. Ann Anat 2011; 193:321-33. [DOI: 10.1016/j.aanat.2011.04.008] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 04/14/2011] [Accepted: 04/18/2011] [Indexed: 01/25/2023]
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Aoyama T, Kumai Y, Yumoto E, Ito T, Miyamaru S. Effects of nerve-muscle pedicle on immobile rat vocal folds in the presence of partial innervation. Ann Otol Rhinol Laryngol 2011; 119:823-9. [PMID: 21250554 DOI: 10.1177/000348941011901206] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVES We investigated whether implantation of an ansa cervicalis nerve (ACN)-muscle pedicle into the thyroarytenoid (TA) muscle is efficacious in the presence of partial recurrent laryngeal nerve (RLN) innervation. METHODS We studied a total of 36 rats. Twelve of the rats served as positive and negative control animals. In the remaining 24 rats, the left RLN was transected, a 1-mm piece of nerve was removed, and the stumps were abutted in silicone tubes (STs), inducing partial RLN regeneration. Twelve of the ST-treated rats underwent this procedure alone, and the other 12 rats had a nerve-muscle pedicle (NMP) implanted into the left TA muscle 5 weeks after ST treatment. At 15 weeks, reinnervation was assessed by histologic evaluation of the TA muscle and by electromyography with stimulation of the RLNs and ACNs. RESULTS The muscle area, the number of nerve terminals, the number of acetylcholine receptors, and the ratio of nerve terminals to acetylcholine receptors were significantly greater (p < 0.05) in the NMP group than in the ST group. Electromyography elicited TA muscle compound action potentials upon stimulation of the RLNs and ACNs. CONCLUSIONS In rats, NMP implantation is efficacious for reducing atrophic changes in the TA muscle in the presence of partial RLN innervation.
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Affiliation(s)
- Takashi Aoyama
- Department of Otolaryngology-Head and Neck Surgery, Kumamoto University School of Medicine, Kumamoto, Japan
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Aagaard P, Suetta C, Caserotti P, Magnusson SP, Kjaer M. Role of the nervous system in sarcopenia and muscle atrophy with aging: strength training as a countermeasure. Scand J Med Sci Sports 2010; 20:49-64. [PMID: 20487503 DOI: 10.1111/j.1600-0838.2009.01084.x] [Citation(s) in RCA: 452] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Aging is characterized by loss of spinal motor neurons (MNs) due to apoptosis, reduced insulin-like growth factor I signaling, elevated amounts of circulating cytokines, and increased cell oxidative stress. The age-related loss of spinal MNs is paralleled by a reduction in muscle fiber number and size (sarcopenia), resulting in impaired mechanical muscle performance that in turn leads to a reduced functional capacity during everyday tasks. Concurrently, maximum muscle strength, power, and rate of force development are decreased with aging, even in highly trained master athletes. The impairment in muscle mechanical function is accompanied and partly caused by an age-related loss in neuromuscular function that comprise changes in maximal MN firing frequency, agonist muscle activation, antagonist muscle coactivation, force steadiness, and spinal inhibitory circuitry. Strength training appears to elicit effective countermeasures in elderly individuals even at a very old age (>80 years) by evoking muscle hypertrophy along with substantial changes in neuromuscular function, respectively. Notably, the training-induced changes in muscle mass and nervous system function leads to an improved functional capacity during activities of daily living.
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Affiliation(s)
- P Aagaard
- Institute of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark.
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Recovery of whisking function after manual stimulation of denervated vibrissal muscles requires brain-derived neurotrophic factor and its receptor tyrosine kinase B. Neuroscience 2010; 170:372-80. [PMID: 20600640 DOI: 10.1016/j.neuroscience.2010.06.053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 06/12/2010] [Accepted: 06/22/2010] [Indexed: 01/27/2023]
Abstract
Functional recovery following facial nerve injury is poor. Neuromuscular junctions (NMJs) are "bridged" by terminal Schwann cells and numerous regenerating axonal sprouts. We have shown that this poly-innervation of NMJs can be reduced by manual stimulation (MS) with restoration of whisking function. In addition, we have recently reported that insulin-like growth factor-1 (IGF-1) is required to mediate the beneficial effects of MS. Here we extend our findings to brain derived neurotrophic factor (BDNF). We then examined the effect of MS after facial-facial anastomosis (FFA) in heterozygous mice deficient in BDNF (BDNF(+/-)) or in its receptor TrkB (TrkB(+/-)). We quantified vibrissal motor performance and the percentage of NMJ bridged by S100-positive terminal Schwann cells. In intact BDNF(+/-) or TrkB(+/-) mice and their wild type (WT) littermates, there were no differences in vibrissal whisking nor in the percentage of bridged NMJ (0% in each genotype). After FFA and handling alone (i.e. no MS) in WT animals, vibrissal whisking amplitude was reduced (60% lower than intact) and the percentage of bridged NMJ increased (27% more than intact). MS improved both the amplitude of vibrissal whisking (not significantly different from intact) and the percentage of bridged NMJ (11% more than intact). After FFA and handling in BDNF(+/-) or TrkB(+/-) mice, whisking amplitude was again reduced (53% and 60% lower than intact) and proportion of bridged NMJ increased (24% and 29% more than intact). However, MS failed to improve outcome in both heterozygous strains (whisking amplitude 55% and 58% lower than intact; proportion of bridged NMJ 27% and 18% more than intact). We conclude that BDNF and TRkB are required to mediate the effects of MS on target muscle reinnervation and recovery of whisking function.
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Gordon T, Tyreman N. Sprouting capacity of lumbar motoneurons in normal and hemisected spinal cords of the rat. J Physiol 2010; 588:2745-68. [PMID: 20519315 DOI: 10.1113/jphysiol.2010.190389] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Nerve sprouting to reinnervate partially denervated muscles is important in several disease and injury states. To examine the effectiveness of sprouting of active and inactive motor units (MUs) and the basis for a limit to sprouting, one of three rat lumbar spinal roots was cut under normal conditions and when the spinal cord was hemisected at T12. Muscle and MU isometric contractile forces were recorded and muscle fibres in glycogen-depleted single muscle units enumerated 23 to 380 days after surgery. Enlargement of intact MUs by sprouting was effective in compensating for up to 80% loss of innervation. For injuries that removed >70-80% of the intact MUs, muscle contractile force and weight dropped sharply. For partial denervation of <70%, all MUs increased contractile force by the same factor in both normally active muscles and muscles whose activity was reduced by T12 hemisection. Direct measurements of MU size by counting glycogen-depleted muscle fibres in physiologically and histochemically defined muscle units, provided direct evidence for a limit in MU size, whether or not the activity of the muscles was reduced by spinal cord hemisection. Analysis of spatial distribution of muscle fibres within the outer boundaries of the muscle unit demonstrated a progressive increase in fibres within the territory to the limit of sprouting when most of the muscle unit fibres were adjacent to each other. We conclude that the upper limit of MU enlargement may be explained by the reinnervation of denervated muscle fibres by axon sprouts within the spatial territory of the muscle unit, formerly distributed in a mosaic pattern.
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Affiliation(s)
- T Gordon
- Department of Surgery, Division of Plastic Surgery, The Hospital for Sick Children, 555 University Ave., Toronto, Ontario, Canada.
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Gordon T, Tyreman N, Li S, Putman C, Hegedus J. Functional over-load saves motor units in the SOD1-G93A transgenic mouse model of amyotrophic lateral sclerosis. Neurobiol Dis 2010; 37:412-22. [DOI: 10.1016/j.nbd.2009.10.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 09/23/2009] [Accepted: 10/22/2009] [Indexed: 01/26/2023] Open
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Aboussouan LS. Mechanisms of exercise limitation and pulmonary rehabilitation for patients with neuromuscular disease. Chron Respir Dis 2010; 6:231-49. [PMID: 19858353 DOI: 10.1177/1479972309345927] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Indications for exercise and pulmonary rehabilitation extend to neuromuscular diseases tough these conditions pose particular challenges given the associated skeletal muscle impairment and respiratory muscle dysfunction. These challenges are compounded by the variety of exercise prescriptions (aerobic, muscle strengthening, and respiratory muscle training) and the variety of neuromuscular disorders (muscular, motor neuron, motor nerve root, and neuromuscular transmission disorders). Studies support a level II evidence of effectiveness (i.e., likely to be effective) for a combination of aerobic exercise and strengthening exercises in muscular disorders, and for strengthening exercises in amyotrophic lateral sclerosis. The potential deleterious effects of work overload in the dystrophinopathies have not been confirmed in Becker muscular dystrophy. Adjunctive pharmacologic interventions (e.g., theophylline, steroids, PDE5 inhibitors, creatine), training recommendations (e.g., interval or lower intensity training) and supportive techniques (e.g., noninvasive ventilation, neuromuscular electrical stimulation, and diaphragm pacing) may result in more effective training but require more study before formal recommendations can be made. The exercise prescription should include avoidance of inspiratory muscle training in hypercapnia or low vital capacity, and should match the desired outcome (e.g., extremity training for task-specific performance, exercise training to enhance exercise performance, respiratory muscle training where respiratory muscle involvement contributes to the impairment).
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Affiliation(s)
- L S Aboussouan
- Cleveland Clinic Foundation, Respiratory Institute, Cleveland, OH 44195, USA.
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Vrbova G, Mehra N, Shanmuganathan H, Tyreman N, Schachner M, Gordon T. Chemical communication between regenerating motor axons and Schwann cells in the growth pathway. Eur J Neurosci 2009; 30:366-75. [PMID: 19656172 DOI: 10.1111/j.1460-9568.2009.06847.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
There are receptors on denervated Schwann cells that may respond to the neurotransmitters that are released from growth cones of regenerating motor axons. In order to ascertain whether the interaction of the transmitters and their receptors plays a role during axon regeneration, we investigated whether pharmacological block of the interaction would reduce the number of motoneurons that regenerate their axons after nerve section and surgical repair. Peripheral nerves in the hindlimbs of rats and mice were cut and repaired, and various drugs were applied to the peripheral nerve stump either directly or via mini-osmotic pumps over a 2-4-week period to block the binding of acetylcholine to nicotinic and muscarinic acetylcholine receptors (AChRs: alpha-bungarotoxin, tubocurarine, atropine and, gallamine) and binding of ATP to P2Y receptors (suramin). In rats, the nicotinic AChR antagonistic drugs and suramin reduced the number of motoneurons that regenerated their axons through the distal nerve stump. In mice, suramin significantly reduced the upregulation of the carbohydrate HNK-1 on the Schwann cells in the distal nerve stump that normally occurs during motor axon regeneration. These data indicate that chemical communication between regenerating axons and Schwann cells during axon regeneration via released neurotransmitters and their receptors may play an important role in axon regeneration.
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Affiliation(s)
- Gerta Vrbova
- Autonomic Neuroscience Centre, Royal Free and University College Medical School, London, UK
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Feng Z, Ko CP. The Role of Glial Cells in the Formation and Maintenance of the Neuromuscular Junction. Ann N Y Acad Sci 2008; 1132:19-28. [DOI: 10.1196/annals.1405.016] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Wright MC, Son YJ. Ciliary neurotrophic factor is not required for terminal sprouting and compensatory reinnervation of neuromuscular synapses: re-evaluation of CNTF null mice. Exp Neurol 2007; 205:437-48. [PMID: 17445802 PMCID: PMC1931609 DOI: 10.1016/j.expneurol.2007.03.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2006] [Revised: 02/28/2007] [Accepted: 03/01/2007] [Indexed: 11/28/2022]
Abstract
Loss of synaptic activity or innervation induces sprouting of intact motor nerve terminals that adds or restores nerve-muscle connectivity. Ciliary neurotrophic factor (CNTF) and terminal Schwann cells (tSCs) have been implicated as molecular and cellular mediators of the compensatory process. We wondered if the previously reported lack of terminal sprouting in CNTF null mice was due to abnormal reactivity of tSCs. To this end, we examined nerve terminal and tSC responses in CNTF null mice using experimental systems that elicited extensive sprouting in wildtype mice. Contrary to the previous report, we found that motor nerve terminals in the null mice sprout extensively in response to major sprouting-stimuli such as exogenously applied CNTF per se, botulinum toxin-elicited paralysis, and partial denervation by L4 spinal root transection. In addition, the number, length and growth patterns of terminal sprouts, and the extent of reinnervation by terminal or nodal sprouts, were similar in wildtype and null mice. tSCs in the null mice were also reactive to the sprouting-stimuli, elaborating cellular processes that accompanied terminal sprouts or guided reinnervation of denervated muscle fibers. Lastly, CNTF was absent in quiescent tSCs in intact, wildtype muscles and little if any was detected in reactive tSCs in denervated muscles. Thus, CNTF is not required for induction of nerve terminal sprouting, for reactivation of tSCs, and for compensatory reinnervation after nerve injury. We interpret these results to support the notion that compensatory sprouting in adult muscles is induced primarily by contact-mediated mechanisms, rather than by diffusible factors.
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Affiliation(s)
- Megan C Wright
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, 2900 W. Queen Lane, Philadelphia, PA 19129, USA
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Abstract
Glial cells are widely distributed throughout the nervous system, including at the chemical synapse. However, our knowledge of the role of glial cells at the synapse is rudimentary. Recent studies using a model synapse, the vertebrate neuromuscular junction (NMJ), have demonstrated that perisynaptic Schwann cells (PSCs), which are the glia juxtaposed to the nerve terminal at the NMJ, play active and essential roles in synaptic function, maintenance, and development. PSCs can respond to nerve activity by increasing intracellular calcium and are capable of modulating synaptic function in response to pharmacological manipulations. Studies using PSC ablation in vivo have shown that PSCs are essential for the long-term maintenance of synaptic structure and function at the adult NMJ. In vivo observations have also shown that PSCs guide presynaptic nerve terminal extension and dictate the pattern of innervation during synaptic regeneration and remodeling at adult NMJs. PSCs may also induce postsynaptic acetylcholine receptor aggregation. Furthermore, PSCs play an essential role in synaptic growth and maintenance during development of NMJs in vivo, and Schwann cell-derived factors can promote synaptogenesis and enhance synaptic transmission in tissue culture. These recent findings advance the emerging concept that glial cells help make bigger, stronger, and more stable synapses.
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Affiliation(s)
- Zhihua Feng
- Section of Neurobiology, Department of Biological Sciences, University of Southern California, Los Angeles, California 90089-2520, USA
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Bontioti E, Kanje M, Lundborg G, Dahlin LB. End-to-side nerve repair in the upper extremity of rat. J Peripher Nerv Syst 2005; 10:58-68. [PMID: 15703019 DOI: 10.1111/j.1085-9489.2005.10109.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The end-to-side nerve-repair technique, i.e., when the distal end of an injured nerve is attached end-to-side to an intact nerve trunk in an attempt to attract nerve fibers by collateral sprouting, has been used clinically. The technique has, however, been questioned. The aim of the present study was to investigate end-to-side repair in the upper extremity of rats with emphasis on functional recovery, source, type, and extent of regenerating fibers. End-to-side repair was used in the upper limb, and the radial or both median/ulnar nerves were attached end-to-side to the musculocutaneous nerve. Pawprints and tetanic muscle force were used to evaluate functional recovery during a 6-month recovery period, and double retrograde labeling was used to detect the source of the regenerated nerve fibers. The pawprints showed that, in end-to-side repair of either one or two recipient nerves, there was a recovery of toe spreading to 60-72% of the preoperative value (lowest value around 47%). Electrical stimulation of the end-to-side attached radial or median/ulnar nerves 6 months after repair resulted in contraction of muscles in the forearm innervated by these nerves (median tetanic muscle force up to 70% of the contralateral side). Retrograde labeling showed that both myelinated (morphometry) sensory and motor axons were recruited to the end-to-side attached nerve and that these axons emerged from the motor and sensory neuronal pool of the brachial plexus. Double retrograde labeling indicated that collateral sprouting was one mechanism by which regeneration occurred. We also found that two recipient nerves could be supported from a single donor nerve. Our results suggest that end-to-side repair may be one alternative to reconstruct a brachial plexus injury when no proximal nerve end is available.
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Affiliation(s)
- Eleana Bontioti
- Department of Hand Surgery, Malmö University Hospital, Malmö, Sweden
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