Metformin and exercise reduce miR-133a expression in skeletal muscles of diabetic rats

Abstract

Abstract Background Exercise training regulates the expression of miRs in diabetes. We investigated the effects of metformin alone or in combination with high-intensity interval training (HIIT) and moderate continuous training (MCT) on miR-133a expression in skeletal muscles of diabetic rats. Sprague-Dawley rats were randomly allocated into nine groups (n = 10 per group): control group (CG), control group + MCT group (CMTG), control group + HIIT group (CHTG), diabetic control group (CDG), diabetic + metformin group (DMG), diabetic + HIIT group (DHTG), diabetic + MCT group (DMTG), diabetic + metformin and MCT group (DMMTG), diabetic + metformin and HIIT group (DMHTG). Type 2 diabetes mellitus was induced in Sprague-Dawley rats and exercise protocols were performed for eight weeks. MiR-133a was extracted from skeletal muscles and their expression profile was determined by real-time reverse-transcription polymerase chain reaction (RT-PCR). Results The expression of miR-133a was increased in skeletal muscles of sedentary diabetic rats (CDG) in comparison to treated (CMTG,CHTG,DMG, DMTG) and healthy controls (CG). Treatment with either HIIT and MCT reduced miR-133a expression, but the combination of HIIT and MCT caused to a further reduction of miR-133a expression in diabetic rats. Conclusion The increased expression of MiR-133a in skeletal muscles of rats can be attenuated by metformin and / or HIIT and MCT. This presents an intervention target that could be used in preventing, treating, and/or delaying diabetes.