Effects of rosiglitazone on the expressions of PGC-1a and GLUT4 in skeletal muscles of aged rats fed by high-fat diets

LIU Min; WANG Chao

doi:10.3969/j.issn.1002-7386.2018.02.001

Abstract：Objective To investigate the effects of rosiglitazone (RSG) on the expressions of PGC-1 α and GLUT4 in skeletal muscles of aged rats fed by high-fat diets,and to observe the changes of insulin sensitivity.Methods The male Wistar rats aged 21 ～ 23 months were divided into three group:control group (n =20),high-fat diet group (HF group,n =20) and RSG intervention group (high-fat diet + RSG,n =20).At the end of the 8th week,the insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp technique.The expression levels of PGC-1 α and GLUT4 in skeletal muscle were detected by polymerase chain reaction (PCR) and Western Blot,respectively.Results As compared with those in control group,the serum levels of triacylglycerol and free fatty acids as well as the triglyceride levels in skeletal muscles in HF group were significantly increased at the end of the 8th,however,the glucose infusion rate in HF group was significantly decreased (P ＜0.05).As compared with those in HF group,the serum levels of triacylglycerol and free fatty acids as well as the triglyceride levels in skeletal muscles in RSG intervention group were significantly decreased at the end of the 8th,however,the glucose infusion rate in HF group was significantly increased (P ＜ 0.05).Moreover,as compared with those in control group,the expression levels of PGC-lα and GLUT4 in skeletal muscles in HF group were significantly decreased,however,the expression levels of PGC-1 α and GLUT4 in RSG intervention group were significantly higher than those in HF group,but,which were still significantly lower than those in control group (P ＜ 0.05).Conclusion The high-fat diet can induce insulin resistance of rats,with down-regulating of expresions of PGC-1 o and GLUT4 in skeletal muscles of aged rats fed by high-fat diet.Moreover RSG intervention can improve insulin resistance and increase the expressions of PGC-1 and GLUT4 in skeletal muscle.