Effects of metformin and swimming exercise on serum visfatin level and visfatin protein expressions in different tissues of obese rats

Objective To observe the the effects of metformin,swimming exercise and the combination of both interventions on the serum visfatin and visfatin protein expression in subcutaneous adipose tissue(SAT),perirenal adipose tissue (PAT) and muscle tissue (MT) of high-fat diet-fed obese rats.Methods 70 SD rats were randomly assigned into normal diet group (ND) (n=10) and high-fat diet group (HD) (n=60).Obese model (n = 40) was established and obese rats were randomly assigned into obese group (OB),metformin group (MET),swinmming exercise group (SWI),and the metformin plus swimming exercise group (M+S)(all n=10).Body weight (BW),fasting plasma glucose(FPG), triglyceride (TG),total cholesterol (TC),fasting insulin (FIns) and fasting visfatin were monitored before and after 6 weeks of treatment.Results BW,FPG,TG,TCH,FIns and visfatin levels of each group in obese model were increased significantly (P0.01 or P0.05).BW,FPG,TG,TC,FIns and visfatin levels were decreased in MET,SWI and M + S groups after treatment (P0.01 or P0.05). Visfatin protein expression levels in SAT,PAT and MT of obese group,especially that of PAT,were increased as compared to ND group (P 0.01 or P0.05).In SAT and PAT,the visfatin expression levels in M + S,MET and SWI,especially in M + S group,were decreased after intervention,visfatin expression levels in MT of M + S,MET,and SWI groups were decreased with no statistical difference. The levels of FPG and FIns were positively related to the lever of visfatin (P0.01 or P0.05). Conclusions Visfatin,which preferentially expresses in viscera adipose tissue,may play a role in the glucolipid metabolism of obese rats.Metformin and swimming exercise can down-regulate visfatin protein expression in SAT and PAT but has no influence on that of MT.