Resveratrol exhibits differential protective effects on fast- and slow-twitch muscles in streptozotocin-induced diabetic rats

Background: This study aimed to investigate the differential protective effect of resveratrol (RSV) on oxidative stress and metabolic signaling pathways in fast- and slow-twitch skeletal muscles of rats with diabetes. Methods: Diabetic rats were induced by streptozotocin (STZ) for 2 weeks and then administered with RSV (1, 10 and 100μg/kg per day) for 1 week. We determined oxidative stress and protein expression by lucigenin-mediated chemiluminescence and Western immunoblot. Results: The superoxide anion production and copper-zinc superoxide dismutase (CuZnSOD) protein level were increased in fast-twitch muscle than in slow-twitch muscle of diabetes. The Akt and glycogen synthase kinase 3 (GSK-3) phosphorylations were reduced in both fast- and slow-twitch muscles of diabetes. Oxidative stress and GSK-3 dephosphorylation were corrected by RSV treatment in both fast- and slow-twitch muscles of diabetes. Furthermore, RSV treatment downregulated CuZnSOD protein level in diabetic fast-twitch muscle. In diabetic slow-twitch muscle, RSV treatment elevated manganese SOD (MnSOD) and phosphorylated Akt protein levels and reduced acetyl-CoA carboxylase (ACC) phosphorylation. Conclusions: Our results suggested that fast-twitch muscle incurred more oxidative stress, whereas slow-twitch muscle altered metabolic signaling molecules activities under diabetic status. The antidiabetic effect of RSV on fast- and slow-twitch skeletal muscles was mediated by different antioxidative and metabolic signals.