Mediation of endogenous antioxidant enzymes and apoptotic signaling by resveratrol following muscle disuse in the gastrocnemius muscles of young and old rats.

Hindlimb suspension (HLS) elicits muscle atrophy, oxidative stress, and apoptosis in skeletal muscle. Increases in oxidative stress can have detrimental effects on muscle mass and function, and it can potentially lead to myonuclear apoptosis. Resveratrol is a naturally occurring polyphenol possessing both antioxidant and antiaging properties. To analyze the capacity of resveratrol to attenuate oxidative stress, apoptosis and muscle force loss were measured following 14 days of HLS. Young (6 mo) and old (34 mo) rats were administered either 12.5 mg·kg(-1)·day(-1) of trans-resveratrol, or 0.1% carboxymethylcellulose for 21 days, including 14 days of HLS. HLS induced a significant decrease in plantarflexor isometric force, but resveratrol blunted this loss in old animals. Resveratrol increased gastrocnemius catalase activity, MnSOD activity, and MnSOD protein content following HLS. Resveratrol reduced hydrogen peroxide and lipid peroxidation levels in muscles from old animals after HLS. Caspase 9 abundance was reduced and Bcl-2 was increased, but other apoptotic markers were not affected by resveratrol in the gastrocnemius muscle after HLS. The data indicate that resveratrol has a protective effect against oxidative stress and muscle force loss in old HLS animals; however, resveratrol was unable to attenuate apoptosis following HLS. These results suggest that resveratrol has the potential to be an effective therapeutic agent to treat muscle functional decrements via improving the redox status associated with disuse.