白藜芦醇通过介导Nrf2/HO-1/GPX4信号通路抑制铁死亡改善肝纤维化的机制研究OA

Objective:To investigate the potential mechanism by which resveratrol inhibits ferroptosis to ameliorate liver fibrosis by mediating the nuclear factor E2-related factor 2(NRF2)/heme oxygenase 1(HO-1)/glutathione peroxidase 4(GPX4)signaling pathway.Methods:SPF-grade SD rats were randomized into normal control,model control,resveratrol(25,50,and 100 mg/kg),and colchicine(0.2 mg/kg)groups.A liver fibrosis model was established by subcutaneous injection of 40%CCl4 olive oil solution for 12 weeks.From the 7th week,each group was administrated with correspond-ing drugs once daily for 6 consecutive weeks.The microplate method was used to measure the hepatocyte injury indica-tors alanine aminotransferase(ALT)and aspartate aminotransferase(AST).Hematoxylin-eosin staining and Masson staining were performed to observe the pathological changes in the liver tissue.Immunohistochemistry was employed to assess the positive expression levels of α-smooth muscle actin(α-SMA)and collagen type I α1(COL1A1).The thio-barbituric acid(TBA)method and microplate method were adopted to measure oxidative stress indicators malondialde-hyde(MDA)and glutathione(GSH),respectively.Prussian blue staining was performed to reveal iron ion deposition in the liver tissue.Western blot was employed to determine the protein levels of solute carrier family 7 member 11(SLC7A11),GPX4,NRF2,and HO-1.Immunofluorescence co-localization was employed to detect the nuclear transloca-tion of NRF2.Results:Compared with the normal control group,the model control group showed elevated serum levels of ALT and AST(P<0.01),significantly enhanced hepatic inflammatory cell infiltration and collagen deposition,increased positive expression of α-SMA and COL1A1(P<0.01),increased MDA content and reduced GSH content in liver tissue homogenate(P<0.01),increased iron ion deposition(P<0.01),down-regulated protein levels of NRF2,HO-1,GPX4,and SLC7A11(P<0.01),and location of NRF2 mostly outside the nucleus.Compared with the model control group,the colchicine(0.2 mg/kg)and resveratrol groups exhibited declined ALT and AST levels(P<0.01 or P<0.05),reduced hepatic inflammatory cell infiltration and collagen deposition,decreased positive expression of α-SMA and COL1A1(P<0.01),lowered MDA level(P<0.01 or P<0.05),raised GSH level(P<0.01),reduced iron ion deposition(P<0.01 or P<0.05),and up-regulated protein levels of Nrf2,HO-1,GPX4,and SLC7A11(P<0.01 or P<0.05).Notably,Nrf2 was predominantly expressed in the nucleus in the resveratrol(100 mg/kg)group.Conclusion:Resveratrol inhibits fer-roptosis by promoting nuclear translocation of NRF2 and mediating the NRF2/HO-1/GPX4 signaling pathway,thus amel-iorating liver fibrosis.