Intervention Of Antioxidant In Non-Alcoholic Fatty Liver

Objective:(1) To establish rat model of non-alcoholic fatty liver rapidly with the improved high fat diet.(2) To study the effects of Vitamin E and Selenium on UCP2 and related elements of rat model of non-alcoholic fatty liver.Methods:Forty male SD rats are used to randomly divide into normal group(n=8),model group (n=8),Vitamin E group(n=8),Selenium group (n=8) and taken combination group (n=8). Normal group are fed with normal diet. Others groups are fed with the improved high fat diet. At the same time, diet for Vitamin E group is with the addition of Vitamin E (250mg/kg diet) , diet for Selenium group is with the addition of Selenite (0.5mg/kg diet). We continuously observe rat's ordinary circumstances and the body weight in 5 weeks. Finally all rats are killed at the end of the fifth week. Pathological changes of rat livers are observed by HE staining, and Sudan IV staining is used to understand presence of lipid droplets in rat hepatocyte of model group. At last, we compare the differences of TG,TC,ALT,AST,MDA,SOD in serum between five group rats, and observe the levels of UCP2mRNA,UCP2 and NF-κB protein in liver tissues of five group rats.Results:(1) Compared with normal group, the weights of rats in model group haven't remarkable increased (P>0.05). Indexes of hepatic lipid: there exist a lot of lipid droplets, confirmed by sudan IV staining in cytoplasm of rat liver cells of model group in the fifth week. Furthermore, we test several biochemical markers of the rats. The levels of TG,TC and ALT in serum of model group rats have remarkable increased respectively to achieve 1.28±0.61mmol/L, 12.78±1.47mmol/L, 91.1±11.16U/L, 13.40±4.24nmol/ml (P<0.05),and the SOD energies in serum of model group rats have remarkable decreased comparing with normal group (P<0.05).The expressions of UCP2,NF-κB proteins and UCP2mRNA have increased in liver tissues of model group (P<0.05).(2) Compared with model group, lipid droplets and swellings are observed in rat liver cells of vitamin E group and a little lipid droplets and swellings also exist in Selenium group. In taken combination group, the symptoms of lipid droplets and swellings have been obviously improved. In addition, a large number of mitochodria, with mild swelling, are found on model group liver tissues by electron microscope. The levels of TG,TC,MDA in rat serum of three intervention groups have remarkable decreased (P <0.05), and the levels of SOD energy in rat serum of three intervention groups have remarkable increased(P <0.05), especially the taken combination group, that indicates the Selenium and Vitamin E have the synergy. Immunohistochemical staining shows that the expressions of UCP2 and NF-κB proteins in rat liver tissues of three intervention groups are weaker than model group (p <0.05). The results of RT-PCR: The UCP2 mRNA level of model group is the highest. The three intervention groups have lower levels of expression (p <0.05). The effect of the taken combination group is the best.Conclusion:(1) The improved method successfully establishes the rat model of non-alcoholic fatty liver in five weeks.(2) UCP2 is up-regulated in NAFLD rats. It accelerates the course of non-alcoholic fatty liver.(3) Through the comparison of intervention effect between Selenium,Vitamin E and Selenium plus Vitamin E, we find that Selenium plus Vitamin E can more effectively reduce the degree of hepatic steatosis to achieve the purpose of delaying or preventing the course of non-alcoholic fatty liver.