The Protective Effects Of Estrogen Against Ischemia-Reperfusion Injury In Rat Liver Transplantation

Objective: To investigate the protective effects of estrogen (E2) against cold ischemia-reperfusion (I/R) injury in rat liver transplantation. Methods: The Sprague Dawley male rats were randomly divided into Sham operation group (Sham group), control group (I/R group) and experimental group (I/R+E2 group). The receptor of experimental group received intraperitoneal injection of 17 beta-estradiol at 500 mu g/kg/day for 7 days, the sham operation group and control group were injected with equal volume of saline. Both control and experimental groups used a modified two-cuff technique of liver transplantation with 4 h for cold ischemia. After 6 h reperfusion, serum ALT, AST, LDH, TNF-alpha and liver tissue MDA, MPO, SOD, Bcl-2 were detected. Survival rate of each group were investigated. Results: (1) Serum ALT, AST, LDH, TNF-alpha content in VR+E2 group were significantly lower compared with those in I/R group (P < 0.05). (2) Liver tissue MDA concentration, MPO activity in I/R+E2 group were significantly decreased than those in I/R group (P < 0.05). (3) Liver tissue Bcl-2 expression and SOD activity in I/R+E2 group were higher than those in I/R group (P < 0.05). (4) E2 pretreatment prolonged the survival time of hepatic graft after I/R. Conclusion: Estrogen has significant protective effects against I/R injury during rat's liver transplantation, and the mechanism of this might be reducing the levels of inflammatory cytokines, improving tissue's antioxidant capacity and slowing down liver cell apoptosis.