Skeletal muscle changes after hemiparetic stroke and potential beneficial effects of exercise intervention strategies.
Stroke is the leading cause of disability in the United States. New evidence reveals significant structural and metabolic changes in skeletal muscle after stroke. Muscle alterations include gross atrophy and shift to fast myosin heavy chain in the hemiparetic (contralateral) leg muscle; both are related to gait deficit severity. The underlying molecular mechanisms of this atrophy and muscle phenotype shift are not known. Inflammatory markers are also present in contralateral leg muscle after stroke. Individuals with stroke have a high prevalence of insulin resistance and diabetes. Skeletal muscle is a major site for insulin-glucose metabolism. Increasing evidence suggests that inflammatory pathway activation and oxidative injury could lead to wasting, altered function, and impaired insulin action in skeletal muscle. The health benefits of exercise in disabled populations have now been recognized. Aerobic exercise improves fitness, strength, and ambulatory performance in subjects with chronic stroke. Therapeutic exercise may modify or reverse skeletal muscle abnormalities.
Division of Gerontology, University of Maryland School of Medicine, Baltimore, MD, USA. cmacko@grecc.umaryland.edu
Charlene E
CE
Hafer-Macko
Alice S
AS
Ryan
Frederick M
FM
Ivey
Richard F
RF
Macko
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D005081:Exercise Therapy / Q000379:methods*; D006429:Hemiplegia / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation*; D006801:Humans; D007328:Insulin / Q000378:metabolism; D035002:Lower Extremity / Q000503:physiopathology*; D018482:Muscle, Skeletal / Q000378:metabolism / Q000503:physiopathology*; D009133:Muscular Atrophy / Q000378:metabolism / Q000503:physiopathology; D018995:Myosin Heavy Chains / Q000378:metabolism; D020127:Recovery of Function; D013119:Spinal Cord Injuries / Q000378:metabolism / Q000503:physiopathology / Q000534:rehabilitation; D020521:Stroke / Q000150:complications / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D016138:Walking / Q000502:physiology
D001786:Blood Glucose; D007328:Insulin; D018995:Myosin Heavy Chains