title: Endurance exercise facilitates relearning of forelimb motor skill after focal ischemia.
abstract: Endurance exercise (i.e. running), by up-regulating brain-derived neurotrophic factor (BDNF) and other modulators of synaptic plasticity, improves attention and learning, both critical components of stroke rehabilitation. We hypothesized that, following middle cerebral artery occlusion in male Sprague-Dawley rats, endurance exercise would act synergistically with a challenging skilled forelimb task to facilitate motor recovery. Animals were randomly assigned to one of four rehabilitation conditions: no rehabilitation, running only, reach training only, and reach training preceded by running (run/reach training) for 5 weeks beginning 5 days after stroke. The behavioral outcome, morphological change and mRNA expression of proteins implicated in neuroplasticity (BDNF, synapsin I and microtubule-associated protein 2) were compared. Endurance exercise on a motorized running wheel, prior to reach training, enhanced recovery of skilled reaching ability but did not transfer to gross motor skills such as postural support (forelimb asymmetry test) and gait (ladder rung walking test). Microtubule-associated protein 2 staining density in the run/reach group was slightly enhanced in the contralateral motor cortex compared with the contralateral sensory and ipsilateral cingulate cortices, suggesting that running preceding reach training may have resulted in more dendritic branching within the motor cortex in this group. No significant differences in mRNA levels were detected among the training paradigms; however, there was a trend toward greater BDNF and synapsin I mRNA in the reaching groups. These findings suggest that exercise facilitates learning of subsequent challenging reaching tasks after stroke, which has the potential to optimize outcomes in patients with stroke.
authors.affiliation: Basic Medical Sciences, Faculty of Medicine, Memorial University, St. John's, NL, Canada A1B 3V6.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ploughman
authors.forename: Zachary
authors.initials: Z
authors.lastname: Attwood
authors.forename: Nicole
authors.initials: N
authors.lastname: White
authors.forename: Jules J E
authors.initials: JJ
authors.lastname: Doré
authors.forename: Dale
authors.initials: D
authors.lastname: Corbett
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D005552:Forelimb / Q000503:physiopathology*; D007839:Functional Laterality; D005786:Gene Expression Regulation / Q000502:physiology; D007511:Ischemia / Q000473:pathology / Q000503:physiopathology / Q000534:rehabilitation*; D008297:Male; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D009048:Motor Skills / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function; D016704:Synapsins / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C489787:MAP2 protein, rat; D008869:Microtubule-Associated Proteins; D016704:Synapsins