Changes of fasting TNF-α,FFAs levels and insulin sensitivity in obesity rats induced by high-fat diet

Objective To observe the changes of fasting FFAs,TNF-αlevels and insulin sensitivity in obesity rats induced by high-fat diet.Method Normal male Wistar rats(9weeks old)were divided into two groups according to taking either normal chow(NC group,3.3Kcal/g,15%-20%calories for fat),or high-fat diet(HF group,5.1Kcal/g,61%calories for fat).Ten weeks later,body weight,visceral fat mass,fasting glucose,fasting insulin,TNF-αand FFAs levels were determined,and HOMA-IR was calculated by the method HOMA-IR=FPG×FINS/22.5.Result Rats of HF group showed significantly body weight and visceral fat mass gain(body weight increased by11.4%in HF group compared with that in NC group,P0.05;Visceral fat mass increased by20.7%in HF compared with that in NC group,P0.01)and developed the insulin resistance(HOMA-IR:HF group,8.88±4.25vs NC group,3.92±2.26,P0.05)after10weeks feeding.The levels of fasting plasma FFAs and TNF-αwere also increased significantly in HF group compared with NC group by80.8%and58.4%(P0.05).But there were no statistical differences in fasting plasma glucose between the two groups(HF:7.89±1.46mmol/L vs NC:8.70±1.59mmol/L,P0.05).Conclusion In this study obesity rat with insulin resistance has be induced successfully with high-fat diet,and the state of insulin resistance of obesity rats is correlated with the increased levels of fasting plasma FFAs and TNF-α.