This study aimed to investigate the protective effect of water extracts of Orychophragmus violaceus seeds on liver injury induced by thioacetamide(TAA) in mice. ICR male mice were randomly divided into seven groups: normal group, model group, bicyclol positive control group(200 mg·kg~(-1)), Kuihua Hugan Tablets group(350 mg·kg~(-1)), O. violaceus seeds low-dose water extract group(125 mg·kg~(-1)), middle-dose water extract group(250 mg·kg~(-1)), and high-dose water extract group(500 mg·kg~(-1)). Intragastric administration was given in all groups at 0.02 mL·g~(-1) body weight, 1 time a day for continuous 4 days. One h after the administration on the 4 th day, the liver injury model was induced by intraperitoneal injection of TAA(100 mg·kg~(-1)). The mice were put to death 24 hours later. Blood and tissues were taken and organ indexes were calculated. The activities of ALT, AST and TBiL in serum were detected. The content of MDA, GSH and the activity of SOD, GSH-Px in liver homogenate were examined by colorimetry method. HE staining was used to observe the pathological changes of liver tissues in mice. The protein expression levels of NF-κB p65, Keap-1, Nrf2, p-p38, p-JNK, p-ERK, Bax, Bcl-2, caspase-3, cleaved caspase-3 and caspase-8 were detected by Western blot. The results showed that as compared with the model group, various O. violaceus seeds groups could significantly improve the pathological conditions of liver and reduce ALT, AST, TBiL activities in serum of mice with liver injury. In the high-dose group, the activities of SOD, GSH-Px and the content of GSH were significantly increased, while MDA content was sharply declined. Meanwhile, O. violaceus seeds extract down-regulated the expressions of Bax, Keap-1, p-p38, p-JNK, p-ERK, NF-κB p65, cleaved caspase-3 and up-regulated the expressions of Nrf2, Bcl-2, caspase-3 and caspase-8. In conclusion, O. violaceus seeds extract exhibited potent protective effect on liver injury induced by TAA in mice, and its mechanism may be related to down-regulating levels of Keap-1, up-regulating the expressions of Nrf2, inhibiting the expressions of p-p38, p-ERK and NF-κB p65 signaling pathway, and inhibiting hepatocyte apoptosis by down-regulating the expressions of p-JNK and Bax and up-regulating the expressions of Bcl-2.
Keywords: NF-κB; Orychophragmus violaceus; acute liver injury; protective effect; thioacetamide(TAA).