Effects Of Resistance/Aerobic Exercise On Skeletal Muscle Ampk/Sirt1 Signaling Pathway In Rats With Muscular Attenuation Syndrome

Objective: To study the effects of resistance/aerobic exercise on the signaling pathway of adenosine monophosphate-activated protein kinase (AMPK)/silencing information regulator 2 related enzyme 1 (Sirt1) in skeletal muscle in rats with muscular attenuating syndrome. Methods: Ten out of 50 healthy SD rats were randomly selected as normal group and the rest of the rats were used to establish the muscle attenuation syndrome model. The successfully modelled rats were randomly divided into the model group, aerobic exercise group, resistance training group, and combined group (aerobic exercise + resistance training), with 10 rats in each group. Rats in the aerobic exercise group received treadmill training and those in the resistance training group received loaded stair climbing exercise, and those in the combined group received all these exercises at the same time. They were trained for 6 weeks, while rats in the normal group and the model group received no intervention. The body weight and skeletal muscle mass index of rats in each group were measured, and the contents of reactive oxygen species (ROS), ryanodine receptor (RYR), nitric oxide synthetase (NOS), Sirt1, adenosine monophosphate (AMP), adenine nucleoside triphosphate (ATP) and AMPK/Sirt1 signaling pathway related proteins expression levels in skeletal muscle of rats were detected. Results: The body weight, muscle mass index, and the levels of ROS, RYR and NOS, Sirt1 activity, ATP and AMP contents, and AMPK and Sirt1 protein expression levels in rat skeletal muscle of the aerobic exercise group, resistance training group and combined group were higher than those in model group respectively (P<0.05). The combination intervention had the best improvement effects on the above indexes and the aerobic exercise was more effective than resistance training (all P<0.05). Conclusion: Aerobic exercise can more significantly improve the body weight and improve the muscle mass index, enzyme activity, the expression level of AMPK/Sirt1 signaling pathway and energy metabolism in skeletal muscle of rats with muscle attenuation syndrome than resistance training. The combination of aerobic exercise and resistance training has synergistic effects on promoting energy metabolism of rats with muscle attenuation syndrome.