OBJECTIVE:To investigate the effects of Zhi Zi (Fructus Gardeniae) on non-alcoholic fatty liver disease (NAFLD) induced by a high-fat diet in the rat.METHODS:A rat model of NAFLD was established using a high-fat diet.Twenty one rats were randomly divided into a normal group,a model group and a Zhi Zi treatment group,7 rats per group.Drinking water and the drug were intragastrically administrated for 5 weeks.Samples were then taken to observe pathological changes of the liver tissue (HE staining); changes in the fat metabolism pathway e.g.triglyceride (TG) and free fatty acid (FFA) content;alterations in liver function,i.e.serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity; and differences in tumor necrosis factor α (TNF-α) and P-IkB protein expression in the liver tissue.RESULTS:Fatty degeneration and vacuole-like changes of different degrees occurred in hepatic cells of the model group.Markers for fat metabolism,serum ALT and AST activities,and expression of TNF-α and P-IkB proteins in liver tissue significantly increased.Fat metabolism in the Zhi Zi group significantly reduced,as shown by a drop in marker levels.Serum ALT and AST activities,and expression ofTNF-α,P-IkB proteins in liver tissue were also significantly decreased in this group.CONCLUSION:Zhi Zi has a very strong inhibitory action on lipidosis and inflammatory injury in the rat model of NAFLD.This mechanism may possibly be related to the inhibition of the free fatty acid metabolism pathway.