Effects Of Resistin On Insulin Resistance In NAFLD Rats

Objective:To investigate the effects of resistin on insulin resistance in rats non-alcoholic fatty liver disease.Methods : A rat model of insulin- resistant fatty liver was established by a high fat diet. The levels of triglyceride (TG), cholesterol (TC), alanine aminotransferase (ALT)and aspartate aminotransferase (AST) ,fasting glucose, fasting insulin ,MDA,SOD energy in serum and insulin sensitivity index (ISI) were detected . The levels of histological changes were observed by HE and sudanⅢstaining.Western blot and RT-PCR were used to measure the dynamic changes ofIRS-2, NF-κB and resistin expression on protein and mRNA levels,respectively . The relationship among resistin and MDA, resistin and SOD, resistin and NF-κB, resistin and IRS-2 were analyzed respectively.Result: Fatty Liver and insulin resistance model was successfully developed proved by TG,TC and histological examination in liver.Compared with control group and model group at each time point, the levels of MDA,the mRNA and protein expression of NF-κB and resistin were increased markedly with the development of NAFLD(p<0.05), while those of SOD, ISI and IRS-2 were decreased significantly (p <0.05). The gene and protein expression of resistin was positively correlated with those of NF-κB and levels of MDA in serum,and was negatively correlated with those of IRS-2 and SOD energy .Conclusion: Insulin resistance in NAFLD may be related with insulin signaling,involved in the decrease of initial factor IRS-2 and the increase of resistin. Resistin can not only inhibit the phosphor ylation of IRS to affect the signal transduction of insulin upstream pathway ,but also increase the occurrence of IR by activating NF-κB to inhibit insulin downstream pathway and maybe involved in lipid peroxidation in liver damage.