[Molecular mechanism of Prunella vulgaris in alleviating autoimmune hepatitis in mice]

Objective To observe the therapeutic effects of Prunella vulgaris on autoimmune hepatitis (AIH) in mice and explore its mechanism. Methods Forty C57BL/6 mice were randomly divided into normal group, AIH model group and 50, 100 and 200 mg/kg Prunella vulgaris-treated AIH groups with 8 mice each. AIH mice were established with mouse liver antigen S100 mixed with Freund's complete adjuvant (S100/FCA) by intraperitoneal injection. One week after modeling, the normal group and AIH model group were gavaged with 0.2 mL normal saline per day, and Prunella vulgaris-treated AIH groups with 50, 100 and 200 mg/kg of Prunella vulgaris instead per day. After 30 days of intervention, we detected the levels of serum aminotransferase (ALT) and aspartate aminotransferase (AST) by Rate method, hepatic histopathological changes by HE staining, the protein expression of IFN-γ, IL-17A and TGF-β by immunohistochemistry, and the protein levels of BAX and caspase-3 by Western blot analysis. Results Compared with the AIH model group, the decrease of ALT and AST was found in the Prunella vulgaris-treated AIH groups. In addition, tissue necrosis and inflammatory cell infiltration in the Prunella vulgaris-treated AIH groups were less than those in the AIH model group. The lower expression of IFN-γ, IL-17A, BAX and caspase-3 were shown in the Prunella vulgaris-treated AIH groups in comparison with the AIH model group. However, anti-inflammatory factor TGF-β increased in the Prunella vulgaris-treated AIH groups compared with the AIH model group. All results were dose-dependent. Conclusion Prunella vulgaris can remarkably lessen the symptoms of AIH mice through its anti-inflammatory and anti-apoptotic effects.