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Nguyen BL, Baumfalk DR, Lapierre-Nguyen SS, Zhong R, Doerr V, Montalvo RN, Wei-LaPierre L, Smuder AJ. Effects of exercise and doxorubicin on acute diaphragm neuromuscular transmission failure. Exp Neurol 2024; 378:114818. [PMID: 38782352 DOI: 10.1016/j.expneurol.2024.114818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 05/09/2024] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
Doxorubicin (DOX) is a highly effective anthracycline antibiotic used to treat a wide variety of cancers including breast cancer, leukemia and lymphoma. Unfortunately, clinical use of DOX is limited due to adverse off-target effects resulting in fatigue, respiratory muscle weakness and dyspnea. The diaphragm is the primary muscle of inspiration and respiratory insufficiency is likely the result of both muscle weakness and neural impairment. However, the contribution of neuropathology to DOX-induced respiratory muscle dysfunction is unclear. We hypothesized that diaphragm weakness following acute DOX exposure is associated with neurotoxicity and that exercise preconditioning is sufficient to improve diaphragm muscle contractility by maintaining neuromuscular integrity. Adult female Sprague-Dawley rats were randomized into four experimental groups: 1) sedentary-saline, 2) sedentary-DOX, 3) exercise-saline or 4) exercise-DOX. Endurance exercise preconditioning consisted of treadmill running for 1 h/day at 30 m/min for 10 days. Twenty-four hours after the last bout of exercise, animals were treated with DOX (20 mg/kg, I.P.) or saline (equal volume). Our results demonstrate that 48-h following DOX administration diaphragm muscle specific force is reduced in sedentary-DOX rats in response to both phrenic nerve and direct diaphragm stimulation. Importantly, endurance exercise preconditioning in DOX-treated rats attenuated the decrease in diaphragm contractile function, reduced neuromuscular transmission failure and altered phrenic nerve morphology. These changes were associated with an exercise-induced reduction in circulating biomarkers of inflammation, nerve injury and reformation. Therefore, the results are consistent with exercise preconditioning as an effective way of reducing respiratory impairment via preservation of phrenic-diaphragm neuromuscular conduction.
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Affiliation(s)
- Branden L Nguyen
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America.
| | - Dryden R Baumfalk
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Stephanie S Lapierre-Nguyen
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Renjia Zhong
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Vivian Doerr
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Ryan N Montalvo
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Lan Wei-LaPierre
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
| | - Ashley J Smuder
- Department Applied Physiology and Kinesiology, University of Florida, 1864 Stadium Rd., Gainesville, FL 32611, United States of America
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Lopes B, Coelho A, Alvites R, Sousa AC, Sousa P, Moreira A, Atayde L, Salgado A, Geuna S, Maurício AC. Animal models in peripheral nerve transection studies: a systematic review on study design and outcomes assessment. Regen Med 2024; 19:189-203. [PMID: 37855207 DOI: 10.2217/rme-2023-0102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023] Open
Abstract
Aim: Peripheral nerve injury regeneration studies using animal models are crucial to different pre-clinical therapeutic approaches efficacy evaluation whatever the surgical technique explored. Materials & methods: A 944 articles systematic review on 'peripheral nerve injury in animal models' over the last 9 years was carried out. Results: It was found that 91% used rodents, and only 9% employed large animals. Different nerves are studied, with generated gaps (10,78 mm) and methods applied for regeneration evaluation uniformed. Sciatic nerve was the most used (88%), followed by median and facial nerves (2.6%), significantly different. Conclusion: There has not been a significant scale-up of the in vivo testing to large animal models (anatomically/physiologically closer to humans), allowing an improvement in translational medicine for clinical cases.
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Affiliation(s)
- Bruna Lopes
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - André Coelho
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - Rui Alvites
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
- Instituto Universitário de Ciências da Saúde (CESPU), Avenida Central de Gandra 1317, Gandra, Paredes, 4585-116, Portugal
| | - Ana Catarina Sousa
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - Patrícia Sousa
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - Alícia Moreira
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - Luís Atayde
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
| | - António Salgado
- Life & Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus de Gualtar, Braga, Portugal
- ICVS/3B's e PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Stefano Geuna
- Department of Clinical & Biological Sciences, & Cavalieri Ottolenghi Neuroscience Institute, University of Turin, Ospedale San Luigi, Orbassano, Turin, 10043, Italy
| | - Ana Colette Maurício
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, No. 228, Porto, 4050-313, Portugal
- Associate Laboratory for Animal & Veterinary Science (AL4AnimalS), Lisboa, 1300-477, Portugal
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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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Cho YH, Seo TB. The role of walking exercise on axonal regrowth and neuropathic pain markers in dorsal root ganglion after sciatic nerve injury. J Exerc Rehabil 2023; 19:320-326. [PMID: 38188130 PMCID: PMC10766449 DOI: 10.12965/jer.2346522.261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 11/13/2023] [Indexed: 01/09/2024] Open
Abstract
The aim of this study was to determine whether walking exercise can regulate the expression level of neuropathic pain- and inflammatory response markers in the ipsilateral lumbar 4 to 6 dorsal root ganglion neurons after sciatic nerve injury (SNI). The experimental rats were randomly divided into seven groups: the normal control group, sedentary groups for 3, 7, and, 14 days postinjury (dpi), and walking exercise groups for 3, 7, and 14 dpi. Western blot techniques were used to evaluate specific neuropathic pain- and cytokine markers and mechanical allodynia was confirmed by paw withdrawal test. Mechanical allodynia was significantly improved in the walking exercise group compared to the sedentary group at all 7, 10, and 14 dpi. Furthermore, growth associated protein 43 and brain-derived neurotrophic factor levels were significantly increased in the walking exercise groups compared to the sedentary group at all 3, 7, and 14 dpi. Conversely, nuclear factor kappa-light-chain-enhancer of activated B cells, interleukin-6, tumor necrosis factor α, calcitonin gene-related peptide, and c-Fos expression levels were significantly decreased in the walking exercise groups compared to the sedentary group at all 3, 7, and 14 dpi. These findings suggest meaningful information that aggressive rehabilitation walking exercise applied early after SNI might be improve mechanical allodynia, neuropathic pain and inflammatory response markers following SNI.
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Affiliation(s)
- Yeong-Hyun Cho
- Department of Kinesiology, College of Natural Science, Jeju National University, Jeju,
Korea
| | - Tae-Beom Seo
- Department of Kinesiology, College of Natural Science, Jeju National University, Jeju,
Korea
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Isaacson RH, Carrasco DI, Holliday H, Kang SS, Khan S, Kim D, Liu X, Ye K, English AW. Treatments with the specific δ-secretase inhibitor, compound 11, promote the regeneration of motor and sensory axons after peripheral nerve injury. Eur J Neurosci 2023; 58:3555-3568. [PMID: 37608574 DOI: 10.1111/ejn.16126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/21/2023] [Accepted: 08/09/2023] [Indexed: 08/24/2023]
Abstract
Limited axon regeneration following peripheral nerve injury may be related to activation of the lysosomal protease, asparaginyl endopeptidase (AEP, δ-secretase) and its degradation of the microtubule associated protein, Tau. Activity of AEP was increased at the site of sciatic nerve transection and repair but blocked in mice treated systemically with a specific AEP inhibitor, compound 11 (CP11). Treatments with CP11 enhanced axon regeneration in vivo. Amplitudes of compound muscle action potentials recorded 4 weeks after nerve transection and repair and 2 weeks after daily treatments with CP11 were double those of vehicle-treated mice. At that time after injury, axons of significantly more motor and sensory neurons had regenerated successfully and reinnervated the tibialis anterior and gastrocnemius muscles in CP11-treated mice than vehicle-treated controls. In cultured adult dorsal root ganglion neurons derived from wild type mice that were treated in vitro for 24 h with CP11, neurites were nearly 50% longer than in vehicle-treated controls and similar to neurite lengths in cultures treated with the TrkB agonist, 7,8-dihydroxyflavone (7,8-DHF). Combined treatment with CP11 and 7,8-DHF did not enhance outgrowth more than treatments with either one alone. Enhanced neurite outgrowth produced by CP11 was found also in the presence of the TrkB inhibitor, ANA-12, indicating that the enhancement was independent of TrkB signalling. Longer neurites were found after CP11 treatment in both TrkB+ and TrkB- neurons. Delta secretase inhibition by CP11 is a treatment for peripheral nerve injury with great potential.
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Affiliation(s)
- Robin H Isaacson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Dario I Carrasco
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Hannah Holliday
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Seong Su Kang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Samia Khan
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - David Kim
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xia Liu
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Keqiang Ye
- Faculty of Life and Health Sciences, and Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
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Maugeri G, Amato A, Sortino M, D Agata V, Musumeci G. The Influence of Exercise on Oxidative Stress after Spinal Cord Injury: A Narrative Review. Antioxidants (Basel) 2023; 12:1401. [PMID: 37507940 PMCID: PMC10376509 DOI: 10.3390/antiox12071401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/30/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
Spinal cord injury (SCI) is an irreversible disease resulting in partial or total loss of sensory and motor function. The pathophysiology of SCI is characterized by an initial primary injury phase followed by a secondary phase in which reactive oxygen species (ROSs) and associated oxidative stress play hallmark roles. Physical exercise is an indispensable means of promoting psychophysical well-being and improving quality of life. It positively influences the neuromuscular, cardiovascular, respiratory, and immune systems. Moreover, exercise may provide a mechanism to regulate the variation and equilibrium between pro-oxidants and antioxidants. After a brief overview of spinal cord anatomy and the different types of spinal cord injury, the purpose of this review is to investigate the evidence regarding the effect of exercise on oxidative stress among individuals with SCI.
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Affiliation(s)
- Grazia Maugeri
- Section of Anatomy, Histology and Movement Sciences, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Alessandra Amato
- Section of Anatomy, Histology and Movement Sciences, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Martina Sortino
- Section of Anatomy, Histology and Movement Sciences, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Velia D Agata
- Section of Anatomy, Histology and Movement Sciences, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
| | - Giuseppe Musumeci
- Section of Anatomy, Histology and Movement Sciences, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy
- Research Center on Motor Activities (CRAM), University of Catania, 95123 Catania, Italy
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Barham M, Andermahr J, Majczyński H, Sławińska U, Vogt J, Neiss WF. Treadmill training of rats after sciatic nerve graft does not alter accuracy of muscle reinnervation. Front Neurol 2023; 13:1050822. [PMID: 36742044 PMCID: PMC9893025 DOI: 10.3389/fneur.2022.1050822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/23/2022] [Indexed: 01/20/2023] Open
Abstract
Background and purpose After peripheral nerve lesions, surgical reconstruction facilitates axonal regeneration and motor reinnervation. However, functional recovery is impaired by aberrant reinnervation. Materials and methods We tested whether training therapy by treadmill exercise (9 × 250 m/week) before (run-idle), after (idle-run), or both before and after (run-run) sciatic nerve graft improves the accuracy of reinnervation in rats. Female Lewis rats (LEW/SsNHsd) were either trained for 12 weeks (run) or not trained (kept under control conditions, idle). The right sciatic nerves were then excised and reconstructed with 5 mm of a congenic allograft. One week later, training started in the run-run and idle-run groups for another 12 weeks. No further training was conducted in the run-idle and idle-idle groups. Reinnervation was measured using the following parameters: counting of retrogradely labeled motoneurons, walking track analysis, and compound muscle action potential (CMAP) recordings. Results In intact rats, the common fibular (peroneal) and the soleus nerve received axons from 549 ± 83 motoneurons. In the run-idle group, 94% of these motoneurons had regenerated 13 weeks after the nerve graft. In the idle-run group, 81% of the normal number of motoneurons had regenerated into the denervated musculature and 87% in both run-run and idle-idle groups. Despite reinnervation, functional outcome was poor: walking tracks indicated no functional improvement of motion in any group. However, in the operated hindlimb of run-idle rats, the CMAP of the soleus muscle reached 11.9 mV (normal 16.3 mV), yet only 6.3-8.1 mV in the other groups. Conclusion Treadmill training neither altered the accuracy of reinnervation nor the functional recovery, and pre-operative training (run-idle) led to a higher motor unit activation after regeneration.
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Affiliation(s)
- Mohammed Barham
- Department II of Anatomy, University of Cologne and University Hospital of Cologne, Cologne, Germany,*Correspondence: Mohammed Barham ✉
| | | | - Henryk Majczyński
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warszawa, Poland
| | - Urszula Sławińska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warszawa, Poland
| | - Johannes Vogt
- Department II of Anatomy, University of Cologne and University Hospital of Cologne, Cologne, Germany,Cluster of Excellence for Aging Research (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Wolfram F. Neiss
- Department I of Anatomy, University of Cologne and University Hospital of Cologne, Cologne, Germany
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The Role of Physical Exercise and Rehabilitative Implications in the Process of Nerve Repair in Peripheral Neuropathies: A Systematic Review. Diagnostics (Basel) 2023; 13:diagnostics13030364. [PMID: 36766469 PMCID: PMC9914426 DOI: 10.3390/diagnostics13030364] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/14/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND The various mechanisms involved in peripheral nerve regeneration, induced by exercise and electrical nerve stimulation, are still unclear. OBJECTIVE The aim of this review was to summarize the influence of physical exercise and/or electrical stimulation on peripheral nerve repair and regeneration and the variation of impact of intervention depending on timing, as well as kind and dosage of the intervention. A literature survey was conducted on PubMed, Scopus, and Web of Science, between February 2021 to July 2021, with an update in September 2022. METHODOLOGY The literature search identified 101,386 articles with the keywords: "peripheral nerve" OR "neuropathy" AND "sprouting" OR "neuroapraxia" OR "axonotmesis" OR "neurotmesis" OR "muscle denervation" OR "denervated muscle" AND "rehabilitation" OR "physical activity" OR "physical exercise" OR "activity" OR "electrical stimulation". A total of 60 publications were included. Eligible studies were focused on evaluating the process of nerve repair (biopsy, electromyographic parameters or biomarker outcomes) after electrical stimulation or physical exercise interventions on humans or animals with peripheral sensory or motor nerve injury. SYNTHESIS This study shows that the literature, especially regarding preclinical research, is mainly in agreement that an early physical program with active exercise and/or electrical stimulation promotes axonal regenerative responses and prevents maladaptive response. This was evaluated by means of changes in electrophysiological recordings of CMAPs for latency amplitude, and the sciatic functional index (SFI). Furthermore, this type of activity can cause an increase in weight and in muscle fiber diameter. Nevertheless, some detrimental effects of exercising and electrical stimulation too early after nerve repair were recorded. CONCLUSION In most preclinical studies, peripheral neuropathy function was associated with improvements after physical exercise and electrical stimulation. For humans, too little research has been conducted on this topic to reach a complete conclusion. This research supports the need for future studies to test the validity of a possible rehabilitation treatment in humans in cases of peripheral neuropathy to help nerve sprouting.
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Talukder MAH, Elfar J, Lee J, Karuman Z, Gurjar A, Govindappa P, Guddadarangaiah J, Manto K, Wandling G, Hegarty J, Waning D. Functional recovery and muscle atrophy in pre-clinical models of peripheral nerve transection and gap-grafting in mice: effects of 4-aminopyridine. Neural Regen Res 2023; 18:439-444. [PMID: 35900443 PMCID: PMC9396510 DOI: 10.4103/1673-5374.346456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
We recently demonstrated a repurposing beneficial effect of 4-aminopyridine (4-AP), a potassium channel blocker, on functional recovery and muscle atrophy after sciatic nerve crush injury in rodents. However, this effect of 4-AP is unknown in nerve transection, gap, and grafting models. To evaluate and compare the functional recovery, nerve morphology, and muscle atrophy, we used a novel stepwise nerve transection with gluing (STG), as well as 7-mm irreparable nerve gap (G-7/0) and 7-mm isografting in 5-mm gap (G-5/7) models in the absence and presence of 4-AP treatment. Following surgery, sciatic functional index was determined weekly to evaluate the direct in vivo global motor functional recovery. After 12 weeks, nerves were processed for whole-mount immunofluorescence imaging, and tibialis anterior muscles were harvested for wet weight and quantitative histomorphological analyses for muscle fiber cross-sectional area and minimal Feret’s diameter. Average post-injury sciatic functional index values in STG and G-5/7 models were significantly greater than those in the G-7/0 model. 4-AP did not affect the sciatic functional index recovery in any model. Compared to STG, nerve imaging revealed more misdirected axons and distorted nerve architecture with isografting. While muscle weight, cross-sectional area, and minimal Feret’s diameter were significantly smaller in G-7/0 model compared with STG and G-5/7, 4-AP treatment significantly increased right TA muscle mass, cross-sectional area, and minimal Feret’s diameter in G-7/0 model. These findings demonstrate that functional recovery and muscle atrophy after peripheral nerve injury are directly related to the intervening nerve gap, and 4-AP exerts differential effects on functional recovery and muscle atrophy.
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Enhancing Motor and Sensory Axon Regeneration after Peripheral Nerve Injury Using Bioluminescent Optogenetics. Int J Mol Sci 2022; 23:ijms232416084. [PMID: 36555724 PMCID: PMC9783325 DOI: 10.3390/ijms232416084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/05/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Introduction-Recovery from peripheral nerve injuries is poor even though injured peripheral axons can regenerate. Novel therapeutic approaches are needed. The most successful preclinical experimental treatments have relied on increasing the activity of the regenerating axons, but the approaches taken are not applicable to many nerve-injured patients. Bioluminescent optogenetics (BL-OG) is a novel method of increasing the excitation of neurons that might be similar to that found with activity-dependent experimental therapies. We investigated the use of BL-OG as an approach to promoting axon regeneration following peripheral nerve injury. Methods-BL-OG uses luminopsins, light-sensing ion channels (opsins) fused with a light-emitting luciferase. When exposed to a luciferase substrate, such as coelenterazine (CTZ), luminopsins expressed in neurons generate bioluminescence and produce excitation through their opsin component. Adeno-associated viral vectors encoding either an excitatory luminopsin (eLMO3) or a mutated form (R115A) that can generate bioluminescence but not excite neurons were injected into mouse sciatic nerves. After retrograde transport and viral transduction, nerves were cut and repaired by simple end-to-end anastomosis, and mice were treated with a single dose of CTZ. Results-Four weeks after nerve injury, compound muscle action potentials (M waves) recorded in response to sciatic nerve stimulation were more than fourfold larger in mice expressing the excitatory luminopsin than in controls expressing the mutant luminopsin. The number of motor and sensory neurons retrogradely labeled from reinnervated muscles in mice expressing eLMO3 was significantly greater than the number in mice expressing the R115A luminopsin and not significantly different from those in intact mice. When viral injection was delayed so that luminopsin expression was induced after nerve injury, a clinically relevant scenario, evoked M waves recorded from reinnervated muscles were significantly larger after injury in eLMO3-expressing mice. Conclusions-Treatment of peripheral nerve injuries using BL-OG has significant potential to enhance axon regeneration and promote functional recovery.
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de Moura JA, de Morais J, Barbosa SMN, Ferreira MC, de Sousa Neto IV, Leite HR, Oliveira MX, Gaiad TP, Santos AP. Negative neuromuscular and functional repercussion of forced swimming after axonotmesis. J Exerc Rehabil 2022; 18:179-186. [PMID: 35846236 PMCID: PMC9271644 DOI: 10.12965/jer.2244150.075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 04/04/2022] [Indexed: 11/22/2022] Open
Abstract
Peripheral nerve injuries are cause of sensory disturbances and in functional abilities, and are associated personal and social costs. Strategies that maximize nerve regeneration and functional recovery are necessary, the exercise is an option. This study evaluated the effects of forced swimming exercise on neuromuscular histomorphometry and on functional recovery in a median nerve crush model. Sixteen Wistar rats underwent median nerve crush and were divided into control group (CG) and swimming group (SG). The forced swimming protocol started one week after the injury and was performed for 1 hr a day, 5 days per week, for 2 weeks. The rats swam with an overload of 5% and 10% of body weight in the first and second week, respectively. The functional recovery was assessed in three moments using the grasping test. On day 21, fragments of the median nerve and of the forearm flexors muscles were removed for histomorphometric analysis. The SG had functional recovery impaired (P<0.001) and presented lower myelinated fibers number, fiber and axon minimal diameter, myelin thickness and g-ratio in the proximal e distal segments of the median nerve (P<0.005) and area muscle fiber (P<0.005) than CG. Also, the SG presented a number of capillaries in the proximal segments of the median nerve greater than CG (P<0.005). The exercise protocol used in this study impaired the regeneration of the median nerve and negatively influenced the functional recovery.
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Affiliation(s)
- Júlia Araújo de Moura
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Jaqueline de Morais
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Samara Maria Neves Barbosa
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Marcílio Coelho Ferreira
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | | | - Hércules Ribeiro Leite
- Departamento de Fisioterapia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Murilo Xavier Oliveira
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Thaís Peixoto Gaiad
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Ana Paula Santos
- Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
- Corresponding author: Ana Paula Santos, Departamento de Fisioterapia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, CEP 39100-000, Brazil,
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12
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Jones EJ, Chiou S, Atherton PJ, Phillips BE, Piasecki M. Ageing and exercise-induced motor unit remodelling. J Physiol 2022; 600:1839-1849. [PMID: 35278221 PMCID: PMC9314090 DOI: 10.1113/jp281726] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 02/14/2022] [Indexed: 11/08/2022] Open
Abstract
A motor unit (MU) comprises the neuron cell body, its corresponding axon and each of the muscle fibres it innervates. Many studies highlight age-related reductions in the number of MUs, yet the ability of a MU to undergo remodelling and to expand to rescue denervated muscle fibres is also a defining feature of MU plasticity. Remodelling of MUs involves two coordinated processes: (i) axonal sprouting and new branching growth from adjacent surviving neurons, and (ii) the formation of key structures around the neuromuscular junction to resume muscle-nerve communication. These processes rely on neurotrophins and coordinated signalling in muscle-nerve interactions. To date, several neurotrophins have attracted focus in animal models, including brain-derived neurotrophic factor and insulin-like growth factors I and II. Exercise in older age has demonstrated benefits in multiple physiological systems including skeletal muscle, yet evidence suggests this may also extend to peripheral MU remodelling. There is, however, a lack of research in humans due to methodological limitations which are easily surmountable in animal models. To improve mechanistic insight of the effects of exercise on MU remodelling with advancing age, future research should focus on combining methodological approaches to explore the in vivo physiological function of the MU alongside alterations of the localised molecular environment.
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Affiliation(s)
- Eleanor J. Jones
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Shin‐Yi Chiou
- School of SportExercise, and Rehabilitation Sciences, MRC‐Versus Arthritis Centre for Musculoskeletal Ageing Research, Centre for Human Brain HealthUniversity of BirminghamBirminghamUK
| | - Philip J. Atherton
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Bethan E. Phillips
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
| | - Mathew Piasecki
- Centre of Metabolism, Ageing & Physiology (COMAP), MRC–Versus Arthritis Centre of Excellence for Musculoskeletal Ageing ResearchNottingham NIHR Biomedical Research CentreSchool of MedicineUniversity of NottinghamNottinghamUK
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13
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Maugeri G, D'Agata V, Trovato B, Roggio F, Castorina A, Vecchio M, Di Rosa M, Musumeci G. The role of exercise on peripheral nerve regeneration: from animal model to clinical application. Heliyon 2021; 7:e08281. [PMID: 34765794 PMCID: PMC8571504 DOI: 10.1016/j.heliyon.2021.e08281] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 06/26/2021] [Accepted: 10/25/2021] [Indexed: 12/15/2022] Open
Abstract
Peripheral nerve injury is a complex condition with a variety of signs and symptoms depending on the severity and nerves involved. Peripheral nerve damage may lead to sensory and motor functions deficits and even lifelong disability, causing important socioeconomic costs worldwide. Despite the increase in knowledge of the mechanisms of injury and regeneration, a full functional recovery is still unsatisfying in the majority of patients. It is well known that exercise promotes physical and psychological well-being, by ameliorating general health. In the last years, there has been a growing interest in evaluating the effects of exercise on the peripheral nervous system. Experimental works with rodent models showed the potential utility of exercise following peripheral nerve injuries, as evinced by increasing axon regeneration, muscle reinnervation, better recovery of strength, muscle mass and higher expression of neurotrophic factors. Moreover, clinical evidence showed positive trends in favour of physical therapy following peripheral nerve damage based on the improvement of range of motion (ROM), muscle power grade and pain. After a brief overview of peripheral nerve anatomy and the different types of nerve injury, the present review aims to summarize the impact of exercise on peripheral nerve regeneration. Some clinical evidence regarding the effect of exercise after peripheral nerve injury will also be discussed.
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Affiliation(s)
- Grazia Maugeri
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95123, Catania, Italy
| | - Velia D'Agata
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95123, Catania, Italy
| | - Bruno Trovato
- Research Center on Motor Activities (CRAM), University of Catania, Via S. Sofia n°97, 95123, Catania, Italy
| | - Federico Roggio
- Research Center on Motor Activities (CRAM), University of Catania, Via S. Sofia n°97, 95123, Catania, Italy
| | - Alessandro Castorina
- Laboratory of Cellular and Molecular Neuroscience (LCMN), School of Life Sciences, Faculty of Science, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007, Australia.,Laboratory of Neural Structure and Function (LNSF), School of Medical Sciences, (Anatomy & Histology), Faculty of Medicine and Health, University of Sydney, Sydney, NSW, 2006, Australia
| | - Michele Vecchio
- Unit of Rehabilitation, Vittorio Emanuele University Hospital, Catania, Italy
| | - Michelino Di Rosa
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95123, Catania, Italy
| | - Giuseppe Musumeci
- Department of Biomedical and Biotechnological Sciences, Human, Histology and Movement Science Section, University of Catania, Via S. Sofia n°87, 95123, Catania, Italy.,Research Center on Motor Activities (CRAM), University of Catania, Via S. Sofia n°97, 95123, Catania, Italy.,Department of Biology, Sbarro Institute for Cancer Research and Molecular Medicine, College of Science and Technology, Temple University, Philadelphia, PA, 19122, USA
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14
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Chakraborty A, Upadhya R, Usman TA, Shetty AK, Rutkowski JM. Chronic VEGFR-3 signaling preserves dendritic arborization and sensitization under stress. Brain Behav Immun 2021; 98:219-233. [PMID: 34389489 PMCID: PMC8511130 DOI: 10.1016/j.bbi.2021.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 07/15/2021] [Accepted: 08/05/2021] [Indexed: 11/15/2022] Open
Abstract
Dendritic arborization is critical for the establishment and maintenance of precise neural circuits. Vascular endothelial growth factor D (VEGF-D), well-characterized as a "lymphangiogenic" growth factor, reportedly maintains dendritic arborization and synaptic strength in the hippocampus of adult mice through VEGF receptor (VEGFR-3) signaling. Here, we investigated the effect of chronic VEGFR-3-specific activation on adipose arbor morphometry using the Adipo-VD mouse, a model of inducible, adipose-specific VEGF-D overexpression. We examined whether adipose tissue innervation was preserved or functionally different in Adipo-VD mice during stress in vivo and if VEGFR-3 signaling afforded neuroprotection to challenged neurons in vitro. Chronic VEGFR-3 signaling in Adipo-VD subcutaneous adipose tissue resulted in a reduction in the dendrite length, dendritic terminal branches (filament length), and dendritic terminal branch volume (filament volume), but increased dendrite branching. We also identified reduced stimulus-evoked excitatory sympathetic nerve activity in Adipo-VD mice. Following 6-hydroxydopamine (6-OHDA) denervation, Adipo-VD dendritic arbors were preserved, including improved dendritic branch volume, length, and dendritic branches than in wildtype tissues. In vitro, we found that chronic elevation of VEGFR-3 signaling in developing mVC neurons changes the dendritic arbor complexity and improves stress-induced structure remodeling. Developing neurons are conferred neuroprotection against stress, potentially by upregulation of proteolytic conversion of pro-BDNF to mature BDNF. Mature neurons, however, display improved dendritic arbor complexity, and unaltered dendritic structural remodeling and improved resistance to stress with VEGFR-3 signaling. Overall, chronically increasing VEGFR-3 signaling in neurons has a synergistic impact on neurosensitization and neuroprotection during stress.
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Affiliation(s)
- Adri Chakraborty
- Division of Lymphatic Biology, Department of Medical Physiology, Texas A&M University College of Medicine, Bryan, TX, USA
| | - Raghavendra Upadhya
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Timaj A. Usman
- Division of Lymphatic Biology, Department of Medical Physiology, Texas A&M University College of Medicine, Bryan, TX, USA
| | - Ashok K. Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA
| | - Joseph M. Rutkowski
- Division of Lymphatic Biology, Department of Medical Physiology, Texas A&M University College of Medicine, Bryan, TX, USA,Correspondence: Joseph M Rutkowski, Texas A&M University College of Medicine, 8447 Riverside Parkway, Bryan, TX 77807 USA, Ph: 979-436-0576,
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15
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Middleton SJ, Perez-Sanchez J, Dawes JM. The structure of sensory afferent compartments in health and disease. J Anat 2021; 241:1186-1210. [PMID: 34528255 PMCID: PMC9558153 DOI: 10.1111/joa.13544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 08/12/2021] [Accepted: 08/30/2021] [Indexed: 12/20/2022] Open
Abstract
Primary sensory neurons are a heterogeneous population of cells able to respond to both innocuous and noxious stimuli. Like most neurons they are highly compartmentalised, allowing them to detect, convey and transfer sensory information. These compartments include specialised sensory endings in the skin, the nodes of Ranvier in myelinated axons, the cell soma and their central terminals in the spinal cord. In this review, we will highlight the importance of these compartments to primary afferent function, describe how these structures are compromised following nerve damage and how this relates to neuropathic pain.
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Affiliation(s)
- Steven J Middleton
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | | | - John M Dawes
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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16
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Gholami F, Khaki R, Mirzaei B, Howatson G. Resistance training improves nerve conduction and arterial stiffness in older adults with diabetic distal symmetrical polyneuropathy: A randomized controlled trial. Exp Gerontol 2021; 153:111481. [PMID: 34280509 DOI: 10.1016/j.exger.2021.111481] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 12/17/2022]
Abstract
Diabetes is the main cause of peripheral neuropathy where older patients are at increased risk of diabetic distal symmetrical polyneuropathy (DSPN) due to age-related nerve degeneration and vascular changes. The aim of the study was to investigate the effect of resistance training on nerve conduction, measures of neuropathy and arterial stiffness in older patients with DSPN. In a randomized controlled trial, thirty-four older adults with type-2 diabetes and peripheral neuropathy were enrolled and randomly assigned to experimental and control groups. The experimental group carried out circuit resistance training (1-3 rounds, 11 exercises, 10-15 reps, 50%-60% of 1RM, 3 times per week) for 12 weeks. Measurements were performed at baseline and 48 h after the intervention. Measures of DSPN including Michigan neuropathy screening instrument (MNSI), Michigan diabetic neuropathy score (MDNS), motor nerve action potential amplitude (APA), sensory and motor nerve conduction velocity (NCV) improved following intervention (p < 0.001, p = 0.001, p = 0.034, p = 0.001, and p = 0.001, respectively). Sensory APA did not change after the intervention (p = 0.139). Cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) improved in the experimental group compared with the control group (p = 0.014 and p = 0.033, respectively). In addition, HbA1C decreased following the 12-week resistance training program (p = 0.002). Older adults with DSPN respond positively to resistance training by improved neuropathy symptoms, nerve conduction, arterial stiffness and glucose regulation. Resistance training offers a positive intervention that can abate the progression of DSPN in older adults.
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Affiliation(s)
- Farhad Gholami
- Faculty of Sport Sciences, Shahrood University of Technology, Shahrood, Semnan, Iran.
| | - Raziyeh Khaki
- Faculty of Sport Sciences, Shahrood University of Technology, Shahrood, Semnan, Iran
| | - Batool Mirzaei
- Faculty of Sport Sciences, Shahrood University of Technology, Shahrood, Semnan, Iran
| | - Glyn Howatson
- Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle upon Tyne, UK; Water Research Group, North West University, Potchefstroom, South Africa
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17
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English AW, Berglund K, Carrasco D, Goebel K, Gross RE, Isaacson R, Mistretta OC, Wynans C. Bioluminescent Optogenetics: A Novel Experimental Therapy to Promote Axon Regeneration after Peripheral Nerve Injury. Int J Mol Sci 2021; 22:ijms22137217. [PMID: 34281270 PMCID: PMC8269199 DOI: 10.3390/ijms22137217] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 11/18/2022] Open
Abstract
Functional recovery after peripheral nerve injury (PNI) is poor, mainly due to the slow and incomplete regeneration of injured axons. Experimental therapies that increase the excitability of the injured axons have proven remarkably successful in promoting regeneration, but their clinical applicability has been limited. Bioluminescent optogenetics (BL-OG) uses luminopsins, fusion proteins of light-generating luciferase and light-sensing ion channels that could be used to increase neuronal excitability if exposed to a suitable substrate. Excitatory luminopsins were expressed in motoneurons of transgenic mice and in wildtype mice transduced with adeno-associated viral vectors. Intraperitoneal administration of coelenterazine (CTZ), a known luciferase substrate, generated intense bioluminescence in peripheral axons. This bioluminescence increased motoneuron excitability. A single administration of CTZ immediately after sciatic nerve transection and repair markedly enhanced motor axon regeneration. Compound muscle action potentials were 3–4 times larger than controls by 4 weeks after injury. The results observed with transgenic mice were comparable to those of mice in which the luminopsin was expressed using viral vectors. Significantly more motoneurons had successfully reinnervated muscle targets four weeks after nerve injury in BL-OG treated mice than in controls. Bioluminescent optogenetics is a promising therapeutic approach to enhancing axon regeneration after PNI.
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Affiliation(s)
- Arthur W. English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
- Department of Rehabilitation Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence:
| | - Ken Berglund
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA 30322, USA; (K.B.); (R.E.G.)
| | - Dario Carrasco
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
| | - Katharina Goebel
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
| | - Robert E. Gross
- Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA 30322, USA; (K.B.); (R.E.G.)
| | - Robin Isaacson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
| | - Olivia C. Mistretta
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
| | - Carly Wynans
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; (D.C.); (K.G.); (R.I.); (O.C.M.); (C.W.)
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18
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Application of electrical stimulation for peripheral nerve regeneration: Stimulation parameters and future horizons. INTERDISCIPLINARY NEUROSURGERY 2021. [DOI: 10.1016/j.inat.2021.101117] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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19
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Kampanis V, Tolou-Dabbaghian B, Zhou L, Roth W, Puttagunta R. Cyclic Stretch of Either PNS or CNS Located Nerves Can Stimulate Neurite Outgrowth. Cells 2020; 10:cells10010032. [PMID: 33379276 PMCID: PMC7824691 DOI: 10.3390/cells10010032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/15/2022] Open
Abstract
The central nervous system (CNS) does not recover from traumatic axonal injury, but the peripheral nervous system (PNS) does. We hypothesize that this fundamental difference in regenerative capacity may be based upon the absence of stimulatory mechanical forces in the CNS due to the protective rigidity of the vertebral column and skull. We developed a bioreactor to apply low-strain cyclic axonal stretch to adult rat dorsal root ganglia (DRG) connected to either the peripheral or central nerves in an explant model for inducing axonal growth. In response, larger diameter DRG neurons, mechanoreceptors and proprioceptors showed enhanced neurite outgrowth as well as increased Activating Transcription Factor 3 (ATF3).
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Affiliation(s)
- Vasileios Kampanis
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
| | - Bahardokht Tolou-Dabbaghian
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
| | - Luming Zhou
- Laboratory of NeuroRegeneration and Repair, Hertie Institute for Clinical Brain Research, University of Tübingen, 72076 Tübingen, Germany;
| | - Wolfgang Roth
- Laboratory for Experimental Neurorehabilitation, Heidelberg University Hospital, 69118 Heidelberg, Germany;
| | - Radhika Puttagunta
- Laboratory for Experimental Neuroregeneration, Spinal Cord Injury Center, Heidelberg University Hospital, 69118 Heidelberg, Germany; (V.K.); (B.T.-D.)
- Correspondence:
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20
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Ribas J, Gomes MA, Montes AM, Ribas C, Duarte JA. Resolution of chronic lower back pain symptoms through high-intensity therapeutic exercise and motor imagery program: a case-report. Physiother Theory Pract 2020; 38:1545-1552. [PMID: 33225789 DOI: 10.1080/09593985.2020.1839985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND AND PURPOSE Nonspecific chronic lower back pain (CLBP) is a difficult to manage clinical condition that is more prevalent in adulthood but also affects adolescents, compromising their well-being and activities of daily living. This case report aimed to describe the clinical evolution of a female adolescent with nonspecific and severe CLBP treated successfully through a combination of high-intensity exercise and motor imagery training. Case Description: A 13-year-old girl with CLBP with radicular pain to the lower limbs, spasms, and movement limitations, for whom pharmacological treatment (i.e. analgesic and muscle relaxant agents) and hydrotherapy, hot wet therapy, and muscle relaxation were unsuccessful. After a careful physiotherapy evaluation, the patient underwent a 36-session intervention, performed 3 times/week for 12 weeks, which was composed of high-intensity therapeutic exercise, adjusted for the patient condition, along with motor imagery training. The patient was reevaluated after the intervention and again 3 years later by the same physiotherapist. Outcomes: The intervention led to a favorable clinical outcome, with pain relief, improved posture, and decreased disability. The patient's clinical condition remained stable at the time of the last follow-up evaluation. Conclusion: These results show that the adjusted combined program led to favorable clinical improvement in the condition, with sustained long-term effects after the intervention.
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Affiliation(s)
- Jorge Ribas
- Department of Morphological Sciences, School of Health, Polytechnic Institute of Porto, Porto, Portugal.,Porto Physio Center, Private Practice, Porto, Portugal
| | - Maria Armanda Gomes
- Department of Anesthesiology, Centro Hospitalar De S. João, Porto, Alameda Prof. Hernâni Monteiro, Porto, Portugal
| | - António Mesquita Montes
- Department of Physiotherapy, Santa Maria Health School, Porto, Portugal.,Department of Physiotherapy and Center for Rehabilitation Research (CIR), School of Health, Polytechnic Institute of Porto, Rua Dr. António Bernardino De Almeida, Porto, Portugal
| | - Cláudia Ribas
- Porto Physio Center, Private Practice, Porto, Portugal
| | - José Alberto Duarte
- Sport Biology Department and Research Centre in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sport, University of Porto, Porto, Portugal
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21
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Schwann Cell Role in Selectivity of Nerve Regeneration. Cells 2020; 9:cells9092131. [PMID: 32962230 PMCID: PMC7563640 DOI: 10.3390/cells9092131] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022] Open
Abstract
Peripheral nerve injuries result in the loss of the motor, sensory and autonomic functions of the denervated segments of the body. Neurons can regenerate after peripheral axotomy, but inaccuracy in reinnervation causes a permanent loss of function that impairs complete recovery. Thus, understanding how regenerating axons respond to their environment and direct their growth is essential to improve the functional outcome of patients with nerve lesions. Schwann cells (SCs) play a crucial role in the regeneration process, but little is known about their contribution to specific reinnervation. Here, we review the mechanisms by which SCs can differentially influence the regeneration of motor and sensory axons. Mature SCs express modality-specific phenotypes that have been associated with the promotion of selective regeneration. These include molecular markers, such as L2/HNK-1 carbohydrate, which is differentially expressed in motor and sensory SCs, or the neurotrophic profile after denervation, which differs remarkably between SC modalities. Other important factors include several molecules implicated in axon-SC interaction. This cell–cell communication through adhesion (e.g., polysialic acid) and inhibitory molecules (e.g., MAG) contributes to guiding growing axons to their targets. As many of these factors can be modulated, further research will allow the design of new strategies to improve functional recovery after peripheral nerve injuries.
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22
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Neves M, Tavares ALF, Reginato A, Kakihata CMM, Bertolini GRF, Ribeiro LFC. Low-Level Laser Therapy in Different Wavelengths on the Tibialis Anterior Muscle of Wistar Rats After Nerve Compression Injury. J Manipulative Physiol Ther 2020; 43:700-707. [PMID: 32896420 DOI: 10.1016/j.jmpt.2019.05.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 04/28/2019] [Accepted: 05/01/2019] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Traumatic injuries are common and may promote disruption of neuromuscular communication, triggering phenomena that lead to nerve degeneration and affect muscle function. A laser accelerates tissue recovery; however, the parameters used are varied, making it difficult to compare studies. The purpose of this study was to evaluate the effect of low-level laser therapy, at 660- and 830-nm wavelengths, on the tibialis anterior muscle of Wistar rats after sciatic nerve compression. METHODS Twenty animals were separated into 4 groups: control, sciatic nerve injury, lesion + 660-nm laser, and lesion + 830-nm laser. In the lesion groups, the right sciatic nerve was surgically exposed and compressed with hemostatic forceps for 30 seconds. After the third postoperative day, the groups with laser therapy were submitted to treatment for 2 weeks totaling 10 applications, performed directly on the surgical scar of the nerve injury. Grip strength was analyzed before and after the nerve injury and during the treatment period. The tibialis anterior muscle was processed for light microscopy, area measurement, smaller diameter, number of fibers, nuclei, and connective tissue. RESULTS The animals submitted to the injury experienced muscular atrophy and morphological changes in the number of muscle fibers and nuclei. In the connective tissue morphometry, there was a decrease in the treated groups compared with the untreated groups. CONCLUSION The laser treatment at different wavelengths showed no improvement in the tibialis anterior muscle of Wistar rats within the morphological and functional aspects evaluated.
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Affiliation(s)
- Morgana Neves
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil
| | - Alana L F Tavares
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil
| | - Aline Reginato
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil
| | - Camila M M Kakihata
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil
| | - Gladson R F Bertolini
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil.
| | - Lucinéia F C Ribeiro
- Graduate Program in Biosciences and Health, State University of Western Paraná (Unioeste), Cascavel, Paraná, Brazil
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Just-Borràs L, Hurtado E, Cilleros-Mañé V, Biondi O, Charbonnier F, Tomàs M, Garcia N, Tomàs J, Lanuza MA. Running and swimming prevent the deregulation of the BDNF/TrkB neurotrophic signalling at the neuromuscular junction in mice with amyotrophic lateral sclerosis. Cell Mol Life Sci 2020; 77:3027-3040. [PMID: 31646358 PMCID: PMC11104938 DOI: 10.1007/s00018-019-03337-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 09/30/2019] [Accepted: 10/04/2019] [Indexed: 12/12/2022]
Abstract
Nerve-induced muscle contraction regulates the BDNF/TrkB neurotrophic signalling to retrogradely modulate neurotransmission and protect the neuromuscular junctions and motoneurons. In muscles with amyotrophic lateral sclerosis, this pathway is strongly misbalanced and neuromuscular junctions are destabilized, which may directly cause the motoneuron degeneration and muscular atrophy observed in this disease. Here, we sought to demonstrate (1) that physical exercise, whose recommendation has been controversial in amyotrophic lateral sclerosis, would be a good option for its therapy, because it normalizes and improves the altered neurotrophin pathway and (2) a plausible molecular mechanism underlying its positive effect. SOD1-G93A mice were trained following either running or swimming-based protocols since the beginning of the symptomatic phase (day 70 of age) until day 115. Next, the full BDNF pathway, including receptors, downstream kinases and proteins related with neurotransmission, was characterized and motoneuron survival was analysed. The results establish that amyotrophic lateral sclerosis-induced damaging molecular changes in the BDNF/TrkB pathway are reduced, prevented or even overcompensated by precisely defined exercise protocols that modulate TrkB isoforms and neurotransmission regulatory proteins and reduce motoneuron death. Altogether, the maintenance of the BDNF/TrkB signalling and the downstream pathway, particularly after the swimming protocol, adds new molecular evidence of the benefits of physical exercise to reduce the impact of amyotrophic lateral sclerosis. These results are encouraging since they reveal an improvement even starting the therapy after the onset of the disease.
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Affiliation(s)
- Laia Just-Borràs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain
| | - Erica Hurtado
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain
| | - Víctor Cilleros-Mañé
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain
| | - Olivier Biondi
- UMR-S1124, INSERM, Faculté des Sciences Fondamentales et Biomédicales, Université Paris Descartes, 45 Rue des Saints-Pères, 75006, Paris, France
| | - Frédéric Charbonnier
- UMR-S1124, INSERM, Faculté des Sciences Fondamentales et Biomédicales, Université Paris Descartes, 45 Rue des Saints-Pères, 75006, Paris, France
| | - Marta Tomàs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain
| | - Neus Garcia
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain
| | - Josep Tomàs
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain.
| | - Maria A Lanuza
- Unitat d'Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili. Sant Llorenç 21, 43201, Reus, Spain.
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Luvisetto S. Botulinum Toxin and Neuronal Regeneration after Traumatic Injury of Central and Peripheral Nervous System. Toxins (Basel) 2020; 12:E434. [PMID: 32630737 PMCID: PMC7404966 DOI: 10.3390/toxins12070434] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 12/12/2022] Open
Abstract
Botulinum neurotoxins (BoNTs) are toxins produced by the bacteria Clostridiumbotulinum, the causing agent for botulism, in different serotypes, seven of which (A-G) are well characterized, while others, such as H or FA, are still debated. BoNTs exert their action by blocking SNARE (soluble N-ethylmale-imide-sensitive factor-attachment protein receptors) complex formation and vesicle release from the neuronal terminal through the specific cleavage of SNARE proteins. The action of BoNTs at the neuromuscular junction has been extensively investigated and knowledge gained in this field has set the foundation for the use of these toxins in a variety of human pathologies characterized by excessive muscle contractions. In parallel, BoNTs became a cosmetic drug due to its power to ward off facial wrinkles following the activity of the mimic muscles. Successively, BoNTs became therapeutic agents that have proven to be successful in the treatment of different neurological disorders, with new indications emerging or being approved each year. In particular, BoNT/A became the treatment of excellence not only for muscle hyperactivity conditions, such as dystonia and spasticity, but also to reduce pain in a series of painful states, such as neuropathic pain, lumbar and myofascial pain, and to treat various dysfunctions of the urinary bladder. This review summarizes recent experimental findings on the potential efficacy of BoNTs in favoring nerve regeneration after traumatic injury in the peripheral nervous system, such as the injury of peripheral nerves, like sciatic nerve, and in the central nervous system, such as spinal cord injury.
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Affiliation(s)
- Siro Luvisetto
- Institute of Biochemistry and Cell Biology, National Research Council of Italy, via Ramarini 32, Monterotondo Scalo, 00015 Rome, Italy
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Kim JE, Cho YH, Seo TB. Treadmill exercise activates ATF3 and ERK1/2 downstream molecules to facilitate axonal regrowth after sciatic nerve injury. J Exerc Rehabil 2020; 16:141-147. [PMID: 32509698 PMCID: PMC7248442 DOI: 10.12965/jer.2040188.094] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 03/27/2020] [Indexed: 01/22/2023] Open
Abstract
The purpose of this study was to investigate the effect of treadmill exer-cise on activating transcription factors such as activating transcription factor 3 (ATF3) and extracellular signal-regulated kinase (ERK1/2) sig-naling pathway to facilitate axonal regrowth after sciatic nerve injury (SNI). The experimental rats divided into the normal control (n=10), sedentary groups for 7 (n=10) and 14 days (n=10) post crush, exercise group for 7 (n=10) and 14 days (n=10) post crush (dpc). The rats in ex-ercise groups run on treadmill device at a speed of 8 m/min for 20 min once a day according to exercise duration. In order to evaluate specific regeneration markers and axonal elongation in injured sciatic nerve, we applied immunofluorescence staining and western blot techniques. Treadmill exercise further increased growth-associated protein (GAP-43) expression and axonal regrowth at 7 and 14 dpc than those in sed-entary group. Among mitogen-activated protein kinase downstream molecules, phospho-ERK1/2 (p-ERK1/2) was enhanced by treadmill ex-ercise at only 7 dpc and decreased to basal level 14 days later. But c-Jun N-terminal kinase, c-Jun, and phospho-cyclic adenosine mono-phosphate response element-binding protein showed a tendency to in-crease continuously until 14 dpc by exercise. ATF3 expression in exer-cise group was upregulated at both 7 and 14 dpc compared to the sed-entary group. These results indicate that treadmill exercise had benefi-cial effect on expression of regeneration-related proteins after SNI, suggesting that exercise might be one of various therapeutic strategies for sciatic nerve regeneration.
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Affiliation(s)
- Ji-Eun Kim
- Department of Kinesiology, College of Natural Science, Jeju National University, Jeju, Korea
| | - Yeong-Hyun Cho
- Department of Kinesiology, College of Natural Science, Jeju National University, Jeju, Korea
| | - Tae-Beom Seo
- Department of Kinesiology, College of Natural Science, Jeju National University, Jeju, Korea
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Zink PJ, Philip BA. Cortical Plasticity in Rehabilitation for Upper Extremity Peripheral Nerve Injury: A Scoping Review. Am J Occup Ther 2020; 74:7401205030p1-7401205030p15. [PMID: 32078514 DOI: 10.5014/ajot.2020.036665] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
IMPORTANCE Poor outcomes after upper extremity peripheral nerve injury (PNI) may arise, in part, from the challenges and complexities of cortical plasticity. Occupational therapy practitioners need to understand how the brain changes after peripheral injury and how principles of cortical plasticity can be applied to improve rehabilitation for clients with PNI. OBJECTIVE To identify the mechanisms of cortical plasticity after PNI and describe how cortical plasticity can contribute to rehabilitation. DATA SOURCES PubMed and Embase (1900-2017) were searched for articles that addressed either (1) the relationship between PNI and cortical plasticity or (2) rehabilitative interventions based on cortical plastic changes after PNI. Study Selection and Data Collectio : PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. Articles were selected if they addressed all of the following concepts: human PNI, cortical plasticity, and rehabilitation. Phantom limb pain and sensation were excluded. FINDINGS Sixty-three articles met the study criteria. The most common evidence level was Level V (46%). We identified four commonly studied mechanisms of cortical plasticity after PNI and the functional implications for each. We found seven rehabilitative interventions based on cortical plasticity: traditional sensory reeducation, activity-based sensory reeducation, selective deafferentation, cross-modal sensory substitution, mirror therapy, mental motor imagery, and action observation with simultaneous peripheral nerve stimulation. CONCLUSION AND RELEVANCE The seven interventions ranged from theoretically well justified (traditional and activity-based sensory reeducation) to unjustified (selective deafferentation). Overall, articles were heterogeneous and of low quality, and future research should prioritize randomized controlled trials for specific neuropathies, interventions, or cortical plasticity mechanisms. WHAT THIS ARTICLE ADDS This article reviews current knowledge about how the brain changes after PNI and how occupational therapy practitioners can take advantage of those changes for rehabilitation.
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Affiliation(s)
- Patrick J Zink
- Patrick J. Zink, MSOT, is Occupational Therapist, Select Physical Therapy, Kansas City, MO. At the time of the study, he was Student, Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO
| | - Benjamin A Philip
- Benjamin A. Philip, PhD, is Assistant Professor, Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO;
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Graessle E. Infant crawling orthosis and home program to strengthen a neurologically impaired upper extremity. J Hand Ther 2019; 31:411-415. [PMID: 28673444 DOI: 10.1016/j.jht.2017.05.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 05/25/2017] [Indexed: 02/03/2023]
Affiliation(s)
- Eileen Graessle
- Department of Occupational Therapy, Rehabilitation Services, Shriners Hospitals for Children-St. Louis, St. Louis, MO, USA.
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Qian Y, Cheng Y, Cai J, Zhao X, Ouyang Y, Yuan WE, Fan C. Advances in electrical and magnetic stimulation on nerve regeneration. Regen Med 2019; 14:969-979. [PMID: 31583954 DOI: 10.2217/rme-2018-0079] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Central and peripheral nerve injuries pose a great threat to people. Complications such as inflammation, muscle atrophy, traumatic neuromas and delayed reinnervation can bring huge challenges to clinical practices and barriers to complete nerve regrowth. Physical interventions such as electrical and magnetic stimulation show satisfactory results with varying parameters for acute and chronic nerve damages. The biological basis of electrical and magnetic stimulation mainly relies on protein synthesis, ion channel regulation and growth factor secretion. This review focuses on the various paradigms used in different models of electrical and magnetic stimulation and their regenerative potentials and underlying mechanisms in nerve injuries. The combination of physical stimulation and conductive biomaterial scaffolds displays an infinite potentiality in translational application in nerve regeneration.
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Affiliation(s)
- Yun Qian
- Department of Orthopedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, PR China
| | - Yuan Cheng
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, & School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Jiangyu Cai
- Department of Sports Medicine & Arthroscopic Surgery, Huashan Hospital, Fudan University, Shanghai, 200040, PR China
| | - Xiaotian Zhao
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, & School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Yuanming Ouyang
- Department of Orthopedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, PR China
- Shanghai Sixth People's Hospital East Affiliated to Shanghai University of Medicine & Health Sciences, Shanghai 201306, PR China
| | - Wei-En Yuan
- Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, & School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Cunyi Fan
- Department of Orthopedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, PR China
- Shanghai Sixth People's Hospital East Affiliated to Shanghai University of Medicine & Health Sciences, Shanghai 201306, PR China
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29
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Guo LY, Lozinski B, Yong VW. Exercise in multiple sclerosis and its models: Focus on the central nervous system outcomes. J Neurosci Res 2019; 98:509-523. [DOI: 10.1002/jnr.24524] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/17/2019] [Accepted: 08/21/2019] [Indexed: 12/30/2022]
Affiliation(s)
- Ling Yi Guo
- Department of Physiology and Pharmacology Western University London Ontario Canada
- Hotchkiss Brain InstituteUniversity of Calgary Calgary Alberta Canada
- Department of Clinical Neurosciences University of Calgary Calgary Alberta Canada
| | - Brian Lozinski
- Hotchkiss Brain InstituteUniversity of Calgary Calgary Alberta Canada
- Department of Clinical Neurosciences University of Calgary Calgary Alberta Canada
| | - Voon Wee Yong
- Hotchkiss Brain InstituteUniversity of Calgary Calgary Alberta Canada
- Department of Clinical Neurosciences University of Calgary Calgary Alberta Canada
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30
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Park S, Liu CY, Ward PJ, Jaiswal PB, English AW. Effects of Repeated 20-Hz Electrical Stimulation on Functional Recovery Following Peripheral Nerve Injury. Neurorehabil Neural Repair 2019; 33:775-784. [PMID: 31328654 DOI: 10.1177/1545968319862563] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
One hour of 20-Hz continuous electrical stimulation (ES) applied at the time of injury promotes the regeneration of axons in cut peripheral nerves. A more robust enhancement of peripheral axon regeneration is achieved by 2 weeks of daily treadmill exercise. We investigated whether repeated applications of brief ES (mES) would be more effective in promoting regeneration than a single application. Sciatic nerves of C57B6 mice were cut and repaired by end-to-end anastomosis. At that time and every third day for 2 weeks, the repaired nerve was stimulated for 1 hour at 20 Hz. In controls, injured mice were either untreated or treated with ES only once. Direct muscle responses recorded from reinnervated muscles in awake animals were observed earlier both in mice treated with ES and mES than untreated controls. Their amplitudes increased progressively over the post transection study period, but the rate of this progression was increased significantly only in animals treated once with ES. Monosynaptic H reflexes recovered to pretransection levels in both untreated and singly treated mice but in the animals treated repeatedly, they were maintained at more than twice that of the same reflexes recorded prior to injury. In anatomical analyses, both excitatory and inhibitory synaptic contacts with the cell bodies of injured motoneurons, including those expressing the vesicular glutamate transporter 1 (VGLUT1), were sustained in mice treated repeatedly but not in singly treated or untreated mice. Repeated ES does not enhance the rate of restoration of functional muscle reinnervation and results in the retention of exaggerated reflexes.
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Affiliation(s)
- Sohee Park
- 1 Emory University School of Medicine, Atlanta, GA, USA
| | - Cai-Yue Liu
- 2 Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Ferreira MC, Oliveira MX, Souza JI, Souza RA, Machado TPG, Santos AP. Effects of two intensities of treadmill exercise on neuromuscular recovery after median nerve crush injury in Wistar rats. J Exerc Rehabil 2019; 15:392-400. [PMID: 31316931 PMCID: PMC6614769 DOI: 10.12965/jer.19.328126.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 04/17/2019] [Indexed: 01/02/2023] Open
Abstract
Considering the potential action of exercise on neuroplasticity and the need to adapt protocols to enhance functional recovery after nerve injury, this study evaluated the effects of two intensities of treadmill exercise on nervous and muscular tissues and functional recovery after nerve crush injury. Wistar rats were distributed into sedentary group (SED), and 10 m/min (EG10) and 17 m/min (EG17) exercise groups. The exercise started one week after the injury. Ten daily sessions were performed with a 2-day interval after the fifth day. The flexor digitorum muscle and two segments of the median nerve were analysed histomorphometrically by light microscopy and computer analysis. Function was evaluated by grasping test, in 3 moments. Approval number: 016/2013. In the proximal segments of the median nerve, the diameter of myelinated fibres and axon, the myelin sheath thickness and the ratio of axon diameter to fibre diameter (g ratio) were significantly larger (P<0.05) in the EG10. The number of myelinated fibres was lesser in the EG17 than the other groups (P<0.05). No difference in the number of myelinated fibres among groups was observed in the distal segments, but the SED presented significantly larger axon and fibre diameters than those that performed exercise. The EG10 presented greater area and diameter of muscle fibres (P<0.05) and functional improvement observed on the 21st day after injury (P<0.05) compared with the EG17 and SED. Continuous exercise at 10 m/min accentuates nerve regeneration, accelerating functional recovery and preventing muscle atrophy.
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Affiliation(s)
- Marcílio Coelho Ferreira
- Postgraduate Program in Rehabilitation and Functional Performance, Department of Physiotherapy, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Murilo X Oliveira
- Postgraduate Program in Rehabilitation and Functional Performance, Department of Physiotherapy, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Josiane I Souza
- Animal Experimentation Center, Department of Physiotherapy, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Renato A Souza
- Federal Institute of South of Minas Gerais, Campus Muzambinho, Muzambinho, Minas Gerais, Brazil
| | - Thaís P G Machado
- Postgraduate Program in Rehabilitation and Functional Performance, Department of Physiotherapy, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
| | - Ana Paula Santos
- Postgraduate Program in Rehabilitation and Functional Performance, Department of Physiotherapy, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil
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McGregor CE, Irwin AM, English AW. The Val66Met BDNF Polymorphism and Peripheral Nerve Injury: Enhanced Regeneration in Mouse Met-Carriers Is Not Further Improved With Activity-Dependent Treatment. Neurorehabil Neural Repair 2019; 33:407-418. [PMID: 31068076 DOI: 10.1177/1545968319846131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Activity-dependent treatments to enhance peripheral nerve regeneration after injury have shown great promise, and clinical trials implementing them have begun. Success of these treatments requires activity-dependent release of brain-derived neurotrophic factor (BDNF). A single nucleotide polymorphism (SNP) in the bdnf gene known as Val66Met, which is found in nearly one third of the human population, results in defective activity-dependent BDNF secretion and could impact the effectiveness of these therapies. Here, we used a mouse model of this SNP to test the efficacy of treadmill exercise in enhancing axon regeneration in animals both heterozygous (V/M) and homozygous (M/M) for the SNP. Axon regeneration was studied 4 weeks after complete transection and repair of the sciatic nerve in both male and female animals, using both electrophysiological and histological outcome measures. Regeneration was enhanced significantly without treatment in V/M mice, compared with wild type (V/V) controls. Unlike V/V mice, treatment of both V/M and M/M mice with treadmill exercise did not result in enhanced regeneration. These results were recapitulated in vitro using dissociated neurons containing the light-sensitive cation channel, channelrhodopsin. Three days after plating, neurites of neurons from V/M and M/M mice were longer than those of V/V neurons. In neurons from V/V mice, but not those from V/M or M/M animals, longer neurites were found after optogenetic stimulation. Taken together, Met-carriers possess an intrinsically greater capacity to regenerate axons in peripheral nerves, but this cannot be enhanced further by activity-dependent treatments.
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Microglial BDNF, PI3K, and p-ERK in the Spinal Cord Are Suppressed by Pulsed Radiofrequency on Dorsal Root Ganglion to Ease SNI-Induced Neuropathic Pain in Rats. Pain Res Manag 2019; 2019:5948686. [PMID: 31182984 PMCID: PMC6512068 DOI: 10.1155/2019/5948686] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/07/2019] [Accepted: 03/28/2019] [Indexed: 12/30/2022]
Abstract
Background Pulsed radiofrequency (PRF) on the dorsal root ganglion (DRG) has been applied to alleviate neuropathic pain effectively, yet the mechanisms underlying pain reduction owing to this treatment are not clarified completely. The activated microglia, brain-derived neurotrophic factor (BDNF), phosphatidylinositol 3-kinase (PI3K), and phosphorylated extracellular signal-regulated kinase (p-ERK) in the spinal cord were demonstrated to be involved in developing neuropathic pain. Also, it has been just known that PRF on DRG inhibits the microglial activation in nerve injury rats. Here, we aim to investigate whether PRF treatment could regulate the levels of BDNF, PI3K, and p-ERK in the spinal cord of rats with spared nerve injury (SNI) via suppressing the spinal microglia activation to ease neuropathic pain. Methods The rats with SNI were intrathecally treated with minocycline (specific microglia inhibitor) or same volume of dimethyl sulfoxide once daily, beginning from 1 h before nerve transection to 7 days. PRF was applied adjacent to the L4-L5 DRG of rats with SNI at 45 V for 6 min on the seventh postoperative day, whereas the free-PRF rats were treated without PRF. The withdrawal thresholds were studied, and the spinal levels of ionized calcium-binding adapter molecule 1 (Iba1), BDNF, PI3K, and p-ERK were calculated by western blot analysis, reverse transcription-polymerase chain reaction, and immunofluorescence. Results The paw withdrawal mechanical threshold and paw withdrawal thermal latency decreased in the ipsilateral hind paws after SNI, and the spinal levels of Iba1, BDNF, PI3K, and p-ERK increased on day 21 after SNI compared with baseline (P < 0.01). An intrathecal injection of minocycline led to the reversal of SNI-induced allodynia and increase in levels of Iba1, BDNF, PI3K, and p-ERK. Withdrawal thresholds recovered partially after a single PRF treatment for 14 days, and SNI-induced microglia hyperactivity, BDNF upregulation, and PI3K and ERK phosphorylation in the spinal cord reduced on D14 due to the PRF procedure. Conclusion Microglial BDNF, PI3K, and p-ERK in the spinal cord are suppressed by the therapy of PRF on DRG to ease SNI-induced neuropathic pain in rats.
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Arbat-Plana A, Puigdomenech M, Navarro X, Udina E. Role of Noradrenergic Inputs From Locus Coeruleus on Changes Induced on Axotomized Motoneurons by Physical Exercise. Front Cell Neurosci 2019; 13:65. [PMID: 30863285 PMCID: PMC6399159 DOI: 10.3389/fncel.2019.00065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 02/11/2019] [Indexed: 11/13/2022] Open
Abstract
Physical rehabilitation is one of the cornerstones for the treatment of lesions of the nervous system. After peripheral nerve injuries, activity dependent therapies promote trophic support for the paralyzed muscles, enhance axonal growth and also modulate the maladaptive plastic changes induced by the injury at the spinal level. We have previously demonstrated that an intensive protocol of treadmill running (TR) in rats reduces synaptic stripping on axotomized motoneurons, preserves their perineuronal nets (PNN) and attenuates microglia reactivity. However, it is not clear through which mechanisms exercise is exerting these effects. Here we aimed to evaluate if activation of the locus coeruleus (LC), the noradrenergic center in the brain stem, plays a role in these effects. Since LC is strongly activated during stressful situations, as during intensive exercise, we selectively destroyed the LC by administering the neurotoxin DPS-4 before injuring the sciatic nerve of adult rats. Animals without LC had increased microglia reactivity around injured motoneurons. In these animals, an increasing intensity protocol of TR was not able to prevent synaptic stripping on axotomized motoneurons and the reduction in the thickness of their PNN. In contrast, TR was still able to attenuate microglia reactivity in DSP-4 treated animals, thus indicating that the noradrenergic projections are important for some but not all the effects that exercise induces on the spinal cord after peripheral nerve injury. Moreover, animals subjected to treadmill training showed delayed muscle reinnervation, more evident if treated with DSP-4. However, we did not find differences in treated animals regarding the H/M amplitude ratio, which increased during the first stages of regeneration in all injured groups.
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Affiliation(s)
- Ariadna Arbat-Plana
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Maria Puigdomenech
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Xavier Navarro
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Esther Udina
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Universitat Autònoma de Barcelona, Bellaterra, Spain
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35
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McGregor CE, English AW. The Role of BDNF in Peripheral Nerve Regeneration: Activity-Dependent Treatments and Val66Met. Front Cell Neurosci 2019; 12:522. [PMID: 30687012 PMCID: PMC6336700 DOI: 10.3389/fncel.2018.00522] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/14/2018] [Indexed: 11/29/2022] Open
Abstract
Despite the ability of peripheral nerves to spontaneously regenerate after injury, recovery is generally very poor. The neurotrophins have emerged as an important modulator of axon regeneration, particularly brain derived neurotrophic factor (BDNF). BDNF regulation and signaling, as well as its role in activity-dependent treatments including electrical stimulation, exercise, and optogenetic stimulation are discussed here. The importance of a single nucleotide polymorphism in the BDNF gene, Val66Met, which is present in 30% of the human population and may hinder the efficacy of these treatments in enhancing regeneration after injury is considered. Preliminary data are presented on the effectiveness of one such activity-dependent treatment, electrical stimulation, in enhancing axon regeneration in mice expressing the met allele of the Val66Met polymorphism.
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Affiliation(s)
- Claire Emma McGregor
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
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Pourahmadi M, Hesarikia H, Keshtkar A, Zamani H, Bagheri R, Ghanjal A, Shamsoddini A. Effectiveness of Slump Stretching on Low Back Pain: A Systematic Review and Meta-analysis. PAIN MEDICINE 2018; 20:378-396. [DOI: 10.1093/pm/pny208] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Mohammadreza Pourahmadi
- Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Hamid Hesarikia
- Department of Orthopedic Surgery, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Abbasali Keshtkar
- Department of Health Sciences Education Development, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hamid Zamani
- Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Rasool Bagheri
- Neuromuscular Rehabilitation Research Center, Department of Physiotherapy, Semnan University of Medical Sciences, Semnan, Iran
| | - Ali Ghanjal
- Health Management Research Center, Life Style Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Alireza Shamsoddini
- Exercise Physiology Research Center, Life Style Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
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37
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Lebonvallet N, Laverdet B, Misery L, Desmoulière A, Girard D. New insights into the roles of myofibroblasts and innervation during skin healing and innovative therapies to improve scar innervation. Exp Dermatol 2018; 27:950-958. [DOI: 10.1111/exd.13681] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Nicolas Lebonvallet
- Department of Dermatology and EA4685 “Laboratory Interactions Neurons-Keratinocytes”; Faculty of Medicine and Health Sciences; University of Western Brittany; Brest France
| | - Betty Laverdet
- Department of Physiology and EA6309 “Myelin Maintenance and Peripheral Neuropathies”; Faculty of Pharmacy; University of Limoges; Limoges France
| | - Laurent Misery
- Department of Dermatology and EA4685 “Laboratory Interactions Neurons-Keratinocytes”; Faculty of Medicine and Health Sciences; University of Western Brittany; Brest France
| | - Alexis Desmoulière
- Department of Physiology and EA6309 “Myelin Maintenance and Peripheral Neuropathies”; Faculty of Pharmacy; University of Limoges; Limoges France
| | - Dorothée Girard
- Department of Physiology and EA6309 “Myelin Maintenance and Peripheral Neuropathies”; Faculty of Pharmacy; University of Limoges; Limoges France
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38
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Tai LW, Yeung SC, Cheung CW. Enriched Environment and Effects on Neuropathic Pain: Experimental Findings and Mechanisms. Pain Pract 2018; 18:1068-1082. [PMID: 29722923 DOI: 10.1111/papr.12706] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/04/2018] [Accepted: 04/22/2018] [Indexed: 12/16/2022]
Abstract
Neuropathic pain inflicts tremendous biopsychosocial suffering for patients worldwide. However, safe and effective treatment of neuropathic pain is a prominent unmet clinical need. Environmental enrichment (EE) is an emerging cost-effective nonpharmacological approach to alleviate neuropathic pain and complement rehabilitation care. We present here a review of preclinical studies in ascertaining the efficacy of EE for neuropathic pain. Their proposed mechanisms, including the suppression of ascending nociceptive signaling to the brain, enhancement of the descending inhibitory system, and neuroprotection of the peripheral and central nervous systems, may collectively reduce pain perception and improve somatic and emotional functioning in neuropathic pain. The current evidence offers critical insights for future preclinical research and the translational application of EE in clinical pain management.
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Affiliation(s)
- Lydia Wai Tai
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China.,Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China
| | - Sung Ching Yeung
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China.,Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China
| | - Chi Wai Cheung
- Laboratory and Clinical Research Institute for Pain, Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China.,Department of Anaesthesiology, The University of Hong Kong, Hong Kong, Special Administrative Region, China.,Research Centre of Heart, Brain, Hormone & Healthy Aging, The University of Hong Kong, Hong Kong, Special Administrative Region, China
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Martins DF, Martins TC, Batisti AP, dos Santos Leonel L, Bobinski F, Belmonte LAO, Mazzardo-Martins L, Cargnin-Ferreira E, Santos ARS. Long-Term Regular Eccentric Exercise Decreases Neuropathic Pain-like Behavior and Improves Motor Functional Recovery in an Axonotmesis Mouse Model: the Role of Insulin-like Growth Factor-1. Mol Neurobiol 2017; 55:6155-6168. [DOI: 10.1007/s12035-017-0829-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 12/07/2017] [Indexed: 11/28/2022]
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Arbat‐Plana A, Navarro X, Udina E. Effects of forced, passive, and voluntary exercise on spinal motoneurons changes after peripheral nerve injury. Eur J Neurosci 2017; 46:2885-2892. [DOI: 10.1111/ejn.13739] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 09/26/2017] [Accepted: 10/12/2017] [Indexed: 12/13/2022]
Affiliation(s)
- Ariadna Arbat‐Plana
- Unitat de Fisiologia Mèdica Institute of Neurosciences Department of Cell Biology, Physiology and Immunology Universitat Autònoma de Barcelona Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) Av Can Domènech, Edifici M E‐08193 Bellaterra Spain
| | - Xavier Navarro
- Unitat de Fisiologia Mèdica Institute of Neurosciences Department of Cell Biology, Physiology and Immunology Universitat Autònoma de Barcelona Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) Av Can Domènech, Edifici M E‐08193 Bellaterra Spain
| | - Esther Udina
- Unitat de Fisiologia Mèdica Institute of Neurosciences Department of Cell Biology, Physiology and Immunology Universitat Autònoma de Barcelona Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) Av Can Domènech, Edifici M E‐08193 Bellaterra Spain
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Monoaminergic descending pathways contribute to modulation of neuropathic pain by increasing-intensity treadmill exercise after peripheral nerve injury. Exp Neurol 2017; 299:42-55. [PMID: 28993250 DOI: 10.1016/j.expneurol.2017.10.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 09/16/2017] [Accepted: 10/06/2017] [Indexed: 01/07/2023]
Abstract
This study characterizes the impact of increasing-intensity treadmill exercise (iTR) on noradrenergic (NE) and serotonergic (5HT) modulation of neuropathic pain. Following sciatic nerve transection and repair (SNTR) rats developed significant mechanical and thermal hyperalgesia that was partially prevented by iTR performed during the first 2weeks after injury. Marked decrease in the expression of 5HT2A and α1A and β-, but not α2A adrenergic receptors in the spinal cord dorsal horn was associated to SNTR and recovered by iTR, particularly in lamina II. iTR significantly increased 5HT2A in periaqueductal grey (PAG), raphe magnus (RM) and dorsal raphe nucleus (DRN), with a pattern suggesting reorganization of serotonergic excitatory interconnections between PAG and DRN. iTR also increased the expression of α1A in locus coeruleus (LC) and DRN, and β2 in LC, indicating that exercise enhanced activity of NE neurons, likely by activating autologous projections from DRN and PAG. iTR hypoalgesia was antagonized by blockade of β2 and 5HT2A receptors with administration of butoxamine and ketanserin. The neurotoxin DSP4 was injected to induce depletion of NE projections from LC before starting iTR. DSP4 treatment worsened mechanical hyperalgesia, but iTR hypoalgesia was similarly produced. Moreover, 5HT2A expression in LC further increased after DSP4 injection, all these results suggesting an intrinsic regulation of 5HT and NE activity between PAG, DRN and LC neurons activated by iTR. Finally, iTR significantly reduced microglial reactivity in LC and increased non-microglial BDNF expression, an effect that was reverted by butoxamine, implicating BDNF regulation in central 5HT/NE actions on neuropathic pain.
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Resistance wheel exercise from mid-life has minimal effect on sciatic nerves from old mice in which sarcopenia was prevented. Biogerontology 2017; 18:769-790. [PMID: 28597407 DOI: 10.1007/s10522-017-9714-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 05/31/2017] [Indexed: 12/16/2022]
Abstract
The ability of resistance exercise, initiated from mid-life, to prevent age-related changes in old sciatic nerves, was investigated in male and female C57BL/6J mice. Aging is associated with cellular changes in old sciatic nerves and also loss of skeletal muscle mass and function (sarcopenia). Mature adult mice aged 15 months (M) were subjected to increasing voluntary resistance wheel exercise (RWE) over a period of 8 M until 23 M of age. This prevented sarcopenia in the old 23 M aged male and female mice. Nerves of control sedentary (SED) males at 3, 15 and 23 M of age, showed a decrease in the myelinated axon numbers at 15 and 23 M, a decreased g-ratio and a significantly increased proportion of myelinated nerves containing electron-dense aggregates at 23 M. Myelinated axon and nerve diameter, and axonal area, were increased at 15 M compared with 3 and 23 M. Exercise increased myelinated nerve profiles containing aggregates at 23 M. S100 protein, detected with immunoblotting was increased in sciatic nerves of 23 M old SED females, but not males, compared with 15 M, with no effect of exercise. Other neuronal proteins showed no significant alterations with age, gender or exercise. Overall the RWE had no cellular impact on the aging nerves, apart from an increased number of old nerves containing aggregates. Thus the relationship between cellular changes in aging nerves, and their sustained capacity for stimulation of old skeletal muscles to help maintain healthy muscle mass in response to exercise remains unclear.
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43
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Jaiswal PB, English AW. Chemogenetic enhancement of functional recovery after a sciatic nerve injury. Eur J Neurosci 2017; 45:1252-1257. [PMID: 28244163 DOI: 10.1111/ejn.13550] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/15/2017] [Accepted: 02/22/2017] [Indexed: 11/28/2022]
Abstract
Designer receptors exclusively activated by designer drugs (DREADDs) are chemogenetic tools used to modulate neuronal excitability. We hypothesized that activation of excitatory (Gq) DREADD by its designer ligand, clozapine-N-oxide (CNO), would increase the excitability of neurons whose axons have been transected following peripheral nerve injury, and that this increase will lead to an enhanced functional recovery. The lateral gastrocnemius (LG) muscle of adult female Lewis rats was injected unilaterally with AAV9- hsyn- hM3Dq-mCherry (7.6 × 109 viral genomes/μL) to transduce Gq-DREADD expression in LG neurons. The contralateral LG muscle served as an uninjected control. No significant changes in either spontaneous EMG activity or electrically evoked direct muscle (M) responses were found in either muscle after injection of CNO (1 mg/kg, i.p.). The amplitude of monosynaptic H-reflexes in LG was increased after CNO treatment exclusively in muscles previously injected with virus, suggesting that Gq-DREADD activation increased neuronal excitability. After bilateral sciatic nerve transection and repair, additional rats were treated similarly with CNO for up to three days after injury. Electrophysiological data were collected at 2, 4 and 6 weeks after injury. Evoked EMG responses were observed as early as 2 weeks after injury only in Gq-DREADD expressing virus injected LG muscle. By 4 weeks after injury, both M-response and H-reflex amplitudes were significantly greater in muscles previously injected with viral vector than contralateral, uninjected muscles. Increases in the excitability of injured neurons produced by this novel use of Gq-DREADD were sufficient to promote an enhancement in functional recovery after a sciatic nerve injury.
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Affiliation(s)
- Poonam B Jaiswal
- Department of Cell Biology, Emory University, 615 Michael St, Atlanta, GA, 30322, USA
| | - Arthur W English
- Department of Cell Biology, Emory University, 615 Michael St, Atlanta, GA, 30322, USA
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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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45
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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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46
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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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47
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Björkman A, Weibull A, Svensson H, Dahlin L. Cerebral Reorganization in Patients with Brachial Plexus Birth Injury and Residual Shoulder Problems. Front Neurol 2016; 7:240. [PMID: 28066323 PMCID: PMC5179561 DOI: 10.3389/fneur.2016.00240] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/12/2016] [Indexed: 11/22/2022] Open
Abstract
The functional outcome after a brachial plexus birth injury (BPBI) is based on changes in the peripheral nerve and in the central nervous system. Most patients with a BPBI recover, but residual deficits in shoulder function are not uncommon. The aim of this study was to determine cerebral activation patterns in patients with BPBI and also residual symptoms from the shoulder. In seven patients (six females and one male, aged 17–23 years) with a BPBI and residual shoulder problems (Mallet score IV or lower), the cerebral response to active movement of the shoulder and elbow of the injured and healthy arm was monitored using functional magnetic resonance imaging at 3 T. Movements, i.e., shoulder rotation or elbow flexion and extension, of the injured side resulted in a more pronounced and more extended activation of the contralateral primary sensorimotor cortex compared to the activation seen after moving the healthy shoulder and elbow. In addition, moving the shoulder or elbow on the injured side resulted in increased activation in ipsilateral primary sensorimotor areas an also increased activation in associated sensorimotor areas, in both hemispheres, located further posterior in the parietal lobe, which are known to be important for integration of motor tasks and spatial aspects of motor control. Thus, in this preliminary study based on a small cohort, patients with BPBI and residual shoulder problems show reorganization in sensorimotor areas in both hemispheres of the brain. The increased activation in ipsilateral sensorimotor areas and in areas that deal with both integration of motor tasks and spatial aspects of motor control in both hemispheres indicates altered dynamics between the hemispheres, which may be a cerebral compensation for the injury.
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Affiliation(s)
- Anders Björkman
- Department of Hand Surgery, Skåne University Hospital , Malmö , Sweden
| | - Andreas Weibull
- Department of Radiation Physics, Skåne University Hospital , Malmö , Sweden
| | - Hampus Svensson
- Department of Hand Surgery, Skåne University Hospital , Malmö , Sweden
| | - Lars Dahlin
- Department of Hand Surgery, Skåne University Hospital, Malmö, Sweden; Department of Translational Medicine - Hand Surgery, Lund University, Malmö, Sweden
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Coradini JG, Kunz RI, Kakihata CMM, Errero TK, Bonfleur ML, Ribeiro LDFC, Brancalhão RMC, Bertolini GRF. Swimming does not alter nociception threshold in obese rats submitted to median nerve compression. Neurol Res 2016; 37:1118-24. [PMID: 26923582 DOI: 10.1080/01616412.2015.1114742] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES We, herein, analyzed the effect of swimming on nociception threshold and peripheral nerve regeneration in lean and obese rats submitted to median nerve compression. METHODS To induce obesity, newborn male Wistar rats received injections of monosodium glutamate (MSG), whereas the control (CTL) group received saline. The animals were separated into 6 groups; control and obese (CTL and MSG), control and obese with lesion (CTL LES and MSG LES), and control and obese with lesion submitted to physical exercise (CTL LES PE and MSG LES PE). RESULTS Median nerve compression reduced nociception threshold in CTL LES and MSG LES rats. Swimming effectively altered nociception only in CTL LES PE animals. Lean and obese animals displayed histological differences, when compared to sedentary animals, and exercise improved axon regeneration in both groups. The brain-derived neurotrophic factor and GAP 43 protein expression was greater in animals submitted to nervous compression without alteration by exercise. DISCUSSION In conclusion, swimming, a conservative treatment for peripheral nerve lesions, was not able to improve the nociception threshold in obese rats.
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Affiliation(s)
- Josinéia Gresele Coradini
- 1 Laboratório do Estudo das Lesões e Recursos Fisioterapêuticos, Universidade Estadual do Oeste do Paraná , Cascavel, Brazil
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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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50
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Cannoy J, Crowley S, Jarratt A, Werts KL, Osborne K, Park S, English AW. Upslope treadmill exercise enhances motor axon regeneration but not functional recovery following peripheral nerve injury. J Neurophysiol 2016; 116:1408-17. [PMID: 27466130 DOI: 10.1152/jn.00129.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 06/30/2016] [Indexed: 11/22/2022] Open
Abstract
Following peripheral nerve injury, moderate daily exercise conducted on a level treadmill results in enhanced axon regeneration and modest improvements in functional recovery. If the exercise is conducted on an upwardly inclined treadmill, even more motor axons regenerate successfully and reinnervate muscle targets. Whether this increased motor axon regeneration also results in greater improvement in functional recovery from sciatic nerve injury was studied. Axon regeneration and muscle reinnervation were studied in Lewis rats over an 11 wk postinjury period using stimulus evoked electromyographic (EMG) responses in the soleus muscle of awake animals. Motor axon regeneration and muscle reinnervation were enhanced in slope-trained rats. Direct muscle (M) responses reappeared faster in slope-trained animals than in other groups and ultimately were larger than untreated animals. The amplitude of monosynaptic H reflexes recorded from slope-trained rats remained significantly smaller than all other groups of animals for the duration of the study. The restoration of the amplitude and pattern of locomotor EMG activity in soleus and tibialis anterior and of hindblimb kinematics was studied during treadmill walking on different slopes. Slope-trained rats did not recover the ability to modulate the intensity of locomotor EMG activity with slope. Patterned EMG activity in flexor and extensor muscles was not noted in slope-trained rats. Neither hindblimb length nor limb orientation during level, upslope, or downslope walking was restored in slope-trained rats. Slope training enhanced motor axon regeneration but did not improve functional recovery following sciatic nerve transection and repair.
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Affiliation(s)
- Jill Cannoy
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Sam Crowley
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Allen Jarratt
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Kelly LeFevere Werts
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Krista Osborne
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Sohee Park
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
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