title: Strategies to promote peripheral nerve regeneration: electrical stimulation and/or exercise.
abstract: Enhancing the regeneration of axons is often considered to be a therapeutic target for improving functional recovery after peripheral nerve injury. In this review, the evidence for the efficacy of electrical stimulation (ES), daily exercise and their combination in promoting nerve regeneration after peripheral nerve injuries in both animal models and in human patients is explored. The rationale, effectiveness and molecular basis of ES and exercise in accelerating axon outgrowth are reviewed. In comparing the effects of ES and exercise in enhancing axon regeneration, increased neural activity, neurotrophins and androgens are considered to be common requirements. Similarly, there are sex-specific requirements for exercise to enhance axon regeneration in the periphery and for sustaining synaptic inputs onto injured motoneurons. ES promotes nerve regeneration after delayed nerve repair in humans and rats. The effectiveness of exercise is less clear. Although ES, but not exercise, results in a significant misdirection of regenerating motor axons to reinnervate different muscle targets, the loss of neuromuscular specificity encountered has only a very small impact on resulting functional recovery. Both ES and exercise are promising experimental treatments for peripheral nerve injury that seem to be ready to be translated to clinical use.
authors.affiliation: Division of Plastic Reconstructive Surgery, Department of Surgery, 06.9706 Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Toronto, ON, M4G 1X8, Canada.
authors.forename: Tessa
authors.initials: T
authors.lastname: Gordon
authors.affiliation: Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA.
authors.forename: Arthur W
authors.initials: AW
authors.lastname: English
mesh_terms: D000818:Animals; D004599:Electric Stimulation Therapy; D005081:Exercise Therapy; D006801:Humans; D018482:Muscle, Skeletal / Q000294:innervation; D009416:Nerve Regeneration; D059348:Peripheral Nerve Injuries / Q000503:physiopathology / Q000628:therapy*
keywords: electrical stimulation; exercise and nerve regeneration; exercise or electrical stimulation; nerve stimulation; peripheral nerve regeneration