Objective: To investigate the immunomodulatory effect of oxymatrine on concanavalin A(ConA)-induced liver injury in mice. Method: In the present study

Balb/C mice were randomly divided into five groups:normal group

model group

low and high-dose oxymatrine groups (60

120 mg·kg-1) and bicyclol group (156 mg·kg-1). The mice in the treated groups were administered with oxymatrine (intraperitoneally) or bicyclol (orally) for 5 consecutive days. 30 min after the last medication

all the mice except the normal group were injected with 15 mg·kg-1 of ConA intravenously to establish liver injury models. 8 hours later

blood samples were taken to test the levels of alanine transaminase(ALT)

aspartate aminotransferase(AST)

and total bilrubin(TBIL) in serum

and the liver tissues were taken for HE-staining to evaluate the histopathology changes. The expression levels of serum cytokines interferon-γ(IFN-γ)

tumour necrosis factor-α(TNF-α)

interleukin-4(IL-4)

interleukin-6(IL-6)

interleukin-10(IL-10) and interleukin-27(IL-27) were measured by luminex. Spleen lymphocytes were isolated and the expression levels of CD4+IL-17A and the percentage of CD4+CD25+FoxP3+Treg were tested by flow cytomerty. Results showed that

after con-A injection

the expression levels of ALT

AST and TBIL were increased (P<0.05

P<0.01) as compared with the normal group. As compared with the model group

bicyclol and oxymatrine (60

120 mg·kg-1) could markedly decrease the activity of ALT (P<0.05

P<0.01); oxymatrine at 120 mg·kg-1 could significantly decrease the levels of AST (P<0.05)

and oxymatrine at both 60

120 mg·kg-1 could decrease the levels of TBIL (P<0.05). There were no statistical differences in other groups. All treatment groups could relieve the liver pathological changes to different degrees

and reduce the infiltration of inflammatory cells. After treatment with high dose OMT

the levels of IL-10 and IL-27 were significantly increased (P<0.05). Flow cytomerty results revealed that high dose OMT could significantly decrease the expression levels of CD4+IL-17A (P<0.05) and up-regulate the percentage of CD4+CD25+foxP3+Treg cells (P<0.05). Conclusion: oxymatrine could alleviate ConA-induced liver injury by inhibiting the expression of IL-17A and promoting the proliferation of Treg cells.