Isosteviol plays a protective role on hepatic ischemia and reperfusion injury in mice through MAPK/NF-κB signaling pathway

Abstract Aims The purpose of this paper is to study the effect of isosteviol (ISV) on mice with hepatic ischemia and reperfusion(I/R) injury and further to investigate its underlying mechanism. Methods The blood vessels supplying the left/middle lobe of the liver in mice were clamped to cause liver ischemia for 1h, and then conduct reperfusion for 6 h. ISV or saline was injected intraperitoneally after reperfusion. The expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 in serum and tissues were evaluated by ELISA and qRT-PCR. The infiltration of neutrophils and macrophages into the liver tissue was determined by flow cytometry and myeloperoxidase. Liver HE staining, TUNEL and Annexin V probe were used to determine liver injury and hepatocyte apoptosis. WB was used to investigate the activation of nuclear factor (NF)-κB and c-JunNH2 terminal kinase (JNK), p38 and extracellular regulated protein kinase (ERK), while the expression of apoptosis-related proteins (BCL-2, Bax, caspase3, cleaved-caspase3) was detected. Results ISV reduced AST and ALT levels to alleviate liver injury. ISV significantly reduced the release of inflammatory cytokines and the accumulation of liver neutrophils and microphages. Meanwhile, ISV can promote the expression of anti-apoptosis related protein BCL-2 and inhibit the expression of pro-apoptotic protein Bax and the activation of the protease caspase-3, and reduce the occurrence of hepatocyte apoptosis. Finally, ISV can reduce the phosphorylation level and activation of NF-κB, JNK, p38 and ERK. Conclision ISV inhibit the occurrence of inflammation and hepatocyte apoptosis through MAPK/NF-κB signaling pathway to relieve liver injury.