Exercise Training Promotes Functional Recovery after Spinal Cord Injury

Abstract

The exercise training is an effective therapy for spinal cord injury which has been applied to clinic. Traditionally, the exercise training has been considered to improve spinal cord function only through enhancement, compensation, and replacement of the remaining function of nerve and muscle. Recently, accumulating evidences indicated that exercise training can improve the function in different levels from end-effector organ such as skeletal muscle to cerebral cortex through reshaping skeletal muscle structure and muscle fiber type, regulating physiological and metabolic function of motor neurons in the spinal cord and remodeling function of the cerebral cortex. We compiled published data collected in different animal models and clinical studies into a succinct review of the current state of knowledge.

Blocking of BDNF-TrkB signaling inhibits the promotion effect of neurological function recovery after treadmill training in rats with spinal cord injury

“…As a noninvasive SCI rehabilitation therapy, exercise training increases the expression of BDNF [6,8] and promotes the functional recovery of paralyzed muscles. Additionally, the remodeling of the brain, improvement of the spinal cord microenvironment, and protection of the function of remnant neurons via a variety of mechanisms is promoted [2]. However, to date, a majority of the studies have been focused on assessing the effect of exercise training on BDNF expression and locomotor function recovery, while the critical role in promoting the functional recovery through exercise training is ignored [11].…”

“…After SCI, a marked spinal cord neuronal loss, axonal damage, inflammatory cell infiltration, astrocyte and microglia proliferation, nerve fiber demyelination, and a series of secondary changes may occur [2,3]. In the central nervous system (CNS), the self-repair mechanism is limited post injury, which restricts the effective reorganization and regeneration of the neurons and neural circuits, resulting in a limited spontaneous recovery of the function [4].…”

Forced treadmill running reduces systemic inflammation yet worsens upper limb discomfort in a rat model of work-related musculoskeletal disorders

“…Levels of systemic cytokines are more likely to match muscle and bone inflammatory responses [37,74] (the latter tissue not examined as part of this study). Aerobic exercise is a potent antiinflammatory (locally and systemically) [31,62,75], reduces adipose tissue within and around the exercised tissues [72,76], enhances muscle fiber formation [77,78] and promotes axonal regeneration after peripheral nerve injury [79]. In our case, we suspect that the running task had an additive "repetitive" loading effect on the already strained tissues exposed to the HRHF task and contributed to the injurious cycle.…”

Effect of willed movement training on neurorehabilitation after focal cerebral ischemia and on the neural plasticity-associated signaling pathway

“…Exercise training has been considered to improve neuroplasticity, which leads to enhancement, compensation and replacement of the remaining function of nerve (24). Synaptic activity is decreased following brain injury, however exercise training increases presynaptic release of neurotransmitters, in addition to upregulating postsynaptic response to those neurotransmitters, which can, at least in part, restore neural function following an injury (26). In addition to synaptic activity regulation, new synapse formation, which may compensate for the lost structural circuits, can be triggered by stroke.…”