激活Yes相关蛋白(YAP)抑制铁死亡减轻小鼠急性肝损伤

Activation of Yes-associated protein(YAP)improves mouse acute liver failure by alleviating ferroptosis

目的探索Yes相关蛋白(YAP)可否通过调控铁死亡影响急性肝衰竭的发生发展。方法将8周龄C57BL/6小鼠20只随机分为对照组、急性肝衰竭模型组、YAP激动剂XMU-MP-1干预组和YAP抑制剂维替泊芬(verteporfin)干预组。肝组织HE染色、肝脏生化学检测观察小鼠肝损伤表现;试剂盒检测小鼠肝组织中铁(Fe)、丙二醛(MDA)、谷胱甘肽(GSH)含量;透射电镜观察小鼠肝细胞线粒体改变;荧光定量PCR和Western blot法检测YAP及铁死亡关键基因谷胱甘肽过氧化物酶4(GPX4)、5-脂氧合酶(5-LOX)的表达情况。结果与对照组相比,急性肝衰竭小鼠肝组织严重淤血,可见炎细胞浸润伴肝小叶结构破坏,XMU-MP-1干预组肝损伤减轻。随肝衰竭发生,血浆丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)水平显著升高,XMU-MP-1干预组肝功能改善。此外,电镜观察到肝衰竭小鼠肝细胞内线粒体变小,双层膜密度增高,XMU-MP-1减轻线粒体改变。肝衰竭小鼠肝组织内Fe、MDA水平增加,及GPX4蛋白表达降低、5-LOX表达升高均提示铁死亡参与小鼠急性肝衰竭发生,而活化YAP可抑制铁死亡表现。结论活化YAP可通过抑制铁死亡减轻急性肝衰竭小鼠肝损伤。

Objective To investigate the effects of YAP on the occurrence and progression of acute liver failure by regulating the ferroptosis pathway and its underlying mechanism.Methods A total of 208-week-old C57BL/6 mice were randomly divided into four groups:a control group,an acute liver failure model group,a YAP agonist XMU-MP-1 treatment group and a YAP inhibitor verteporfin treatment group,five mice for each group.HE staining was used to observe the pathological changes of hepatic inflammation and necrosis.Plasma alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels were detected by liver biochemistry.Iron(Fe),malondialdehyde(MDA),glutathione(GSH)determination kits were used to measure their levels in liver tissues of each group.The changes of hepatocyte mitochondrial in each group were observed by electron microscopy.Real time PCR and Western blot analysis were used to detect the mRNA and protein expressions of YAP,glutathione peroxidase 4(GPX4)and 5-lipoxygenase(5-LOX).Results Compared with the control group,mice in the acute liver failure model group and the YAP inhibitor verteporfin treatment group showed severe liver tissue congestion with inflammatory cell infiltration and structural damage to hepatic lobules.Liver injury was alleviated in the XMU-MP-1 treatment group.With the occurrence of liver failure,plasma ALT and AST levels significantly increased,and liver function was improved in XMU-MP-1 treatment group.Electron microscopy showed that mitochondria in hepatocytes of mice with liver failure became smaller and bilayer membrane density increased,while mitochondria changes in the XMU-MP-1 group were alleviated.In addition,the acute liver failure model group showed an increase in Fe and MDA contents,decreased protein expressions of GPX4,and enhanced expression of 5-LOX,suggesting that ferroptosis was involved in acute liver failure in C57BL/6 mice.Ferroptosis was inhibited by activation of YAP.Conclusion Activation of YAP may ameliorate liver injury by inhibiting ferroptosis.