Abstract: Objective To study the expression and effect of silent mating type information regulation 2 homolog 3（SIRT3） in rats with nonalcoholic steatohepatitis（NASH） and evaluate the beneficial intervention of resveratrol on it. Methods The 60 rats were randomly divided into three groups（20 in each）,e.g. normal,NASH and resveratrol-intervened groups. At the end of 24th week,all the rats were sacrificed. Serum biochemical parameters and liver histological ultrastructural characteristics were observed. Reactive oxygen species（ROS） and superoxide dismutase（SOD） in the liver tissues were determined,and SIRT3 protein was assayed by immunohistochemical staining and Western blot. Results The liver index,serum ALT,AST,TG,TC,LDL-C and oxidative stress levels in model rats were significantly higher than those in the normal control（P<0.01）,and all those indicators in resveratrol-intervened group showed significantly lower than in the model group（P<0.01）;the nonalcoholic fatty liver disease activity score（NAS） in model group was （6.83±0.41）,significantly higher than that in the normal group [（0.24±0.08）,P<0.01],and in the treatment group was（3.27±0.29）,significantly lower than in the model group （P<0.01）;the Flameng semiquantitative score of hepatic mitochondria in the model group was （3.24±0.21）,significantly higher than that in the normal group [（0.17±0.03）,P<0.01],and in the treatment group was（1.39±0.12）,significantly lower than that in the model group（P<0.01）;immunohistochemical staining showed that SIRT3 protein appeared both in the cell nucleus and cytoplasm,and the Western blot quantitative detection of SIRT3 protein showed that it was（0.24±0.03） in the model group,significantly lower than that in the normal group[（0.58±0.02）,P<0.01],and in the treatment group was （0.46±0.03）,significantly higher than that in the model group （P<0.01）. Conclusion The SIRT3 expression is decreased in liver tissues of rats with NASH,and resveratrol intervention can improve the expression of the protein,which might alleviate NASH.

Key words: Nonalcoholic steatohepatitis, Silent mating type information regulation 2 homolog 3, Resveratrol, Rats