Tauroursodeoxycholic acid alleviates hepatic ischemia reperfusion injury by suppressing the function of Kupffer cells in mice

The aim of this study is to investigate the protective effect and the mechanism of tauroursodeoxycholic acid (TUDCA) against hepatic ischemia reperfusion (IR) injury. Male Balb/c mice were intraperitoneally injected with tauroursodeoxycholic acid (400 mg/kg) or saline solution, once per day for 3 days before surgery, and then the model of hepatic I/R injury was established. Blood and liver samples were collected from each group at 3, 6, and 24 h after surgery. Liver pathological changes, liver function, hepatocyte apoptosis and proinflammatory factors were detected. KCs were extracted, cultured and treated with TUDCA or phosphate-buffered saline (PBS) for 24h, and then viability and phagocytosis were examined. Additionally, IRE1 alpha/TRAF2/NF-kappa B pathway activity and AML cell apoptosis were detected. The results showed that TUDCA alleviated hepatic I/R injury, the level of liver function markers, and hepatocyte apoptosis in vivo. Furthermore, the proinflammatory effects of KCs were suppressed by down-regulating IRE1 alpha/TRAF2/NF-kappa B pathway activity in vivo. TUDCA dose-dependently suppressed the expression of inflammatory factors and IRE1 alpha/TRAF2/NF-kappa B pathway activity in vitro, consistent with the in vivo results. Therefore, TUDCA can effectively alleviate hepatic IR injury by down-regulating the activity of the IRE1 alpha/TRAF2/NF-kappa B pathway to suppress the function of KCs.