Objective: To study the preventive effect and mechanism of Xiaoyao San on rat acute liver injury induced by Tripterygium wilfordii. Method: Sixty rats were randomly divided into control group

T. wilfordii model group

ganlixin group

low-dose

medium-dose and high-dose groups of Xiaoyao San. Each group was respectively fed with the corresponding dose of drug for 4 days and then fed with decoction of T. wilfordii for 4 days to make the model except control group. Liver indexes was calculated

alanine aminotransferase(ALT)

aspartate aminotransferase(AST)

interleukin-1β(IL-1β)

tumor necrosis factor(TNF)-αwere measured

and liver pathology was detected. Results: Compared with control group

liver indexes

ALT

AST

IL-1β and TNF-α in model group were significantly increased

and significant pathological changes of liver tissue were found(P<0.05 or P<0.01). Compared with model group

all doses group of Xiaoyao San and ganlixin group could effectively decrease liver indexes

ALT

AST

IL-1β

TNF-α and pathological changes of liver tissue (P<0.05 or P<0.01). Compared with ganlixin group

liver indexes

ALT

AST

IL-1β

TNF-α and pathological changes of liver tissue of all doses group of Xiaoyao San was not significantly different. Conclusion: T. wilfordii-induced acute liver injury is associated with inflammatory injury via IL-1β and TNF-α. Xiaoyao San can protect the liver injury induced by T. wilfordii by inhibiting inflammatory injury.