Research On Effect Of Tea Polyphenols And Sodium Selenite's Antioxidative Role On Alcoholic Liver Diasease

Objective:By setting up rat models of alcoholic liver disease and intervene with and tea polyphenols or sodium selenite, To observe the pathology,ultramicro-structure changes, and to investigate the variation of liver damage index and lipid peroxidation, also to investigate the TNF-α,Caspase-3 expression and protein content in liver tissue,Thus to reveal the mechanism of alcoholic liver disease and the effect of the two drugs on alcoholic liver disease, to provide experimental basis for clinical therapy.Methods:Forty-two female Wistar rats weighting between 200g and 250g were divided into four groups randomizedly: model group and control group, sodium selenite treatment group and tea polyphenols intervention group . The model group rats were given alcoholic plus corn oil through intragastric administration .Two intervention groups rats were given alcohol,corn oil and sodium selenite(0.4mg/kg/d)) or tea polyphenols (0.25g/kg/d). The control group rats were only given corn oil . during the experiment period ,the rats fed with basic animal feed . The ethanol was infused chronically, the dose of ethanol increase progressively from 8ml to 15ml/kg by week.All the groups were treated for seven weeks. Then they were killed respectively and determinated the hepatic function parameters and lipid peroxidation index : ALT,AST,MDA content in serum. liver tissue spice was dyed by HE and and SudanⅣ. then analyzed under light microscope. The ultramicro-structure changes were observed under transmission electron microscope.The TNF-αmRNA expression and protein content in liver tissue were measured by semiquantitative RT-PCR and immunochemistry, the concentration of TNF-αin serum were determinated by ELISA. liver immunohistochemical staining was performed by SABC technique to assess the Caspase-3 in liver tissue. Results :1.In the model rats, many drops of lipids infiltration were seen throughout the liver tissue after ethanol infusion for 7 weeks, the index such as ALT,AST, TNF-αCaspase-3 increase significantly compared with control group , P<0.05 2. the tea polyphenols intervention group get better in AST and MDA and lower HE scores (P<0.05)but the ALT has no significantly differnce compared with the model group, (P>0.05), The severity of ultramicro-structure displayed changes paralled with the pathology severity. There was decreased expression of TNF-αand Caspase-3 compared with model group.( P<0.05) 3. In sodium selenite treatment group , large lipid droplets.were noticed in many rat liver tissue but there were little inflammatory cell infiltrated ,and hepatocytes necrosis was rare . AST,TNF-αresults is not difference compared with the model group (P > 0.05) , MDA,caspase-3 has significantly difference(P<0.05)。The indexs is not paralled with each other .Conclusions: Ethanol can damage liver, lipid peroxidation is exist in ALD.We infer that tea polyphenols has protective role in alcoholic liver damage,the mechanism is related to the decrese of TNF-αAnd tea polyphenols may influence the cell apotosis in alcoholic liver disease. The role of Sodium selenite with the dose of 0.4mg/kg/d through intragastric administration can't protect the liver.