大叶茜草素对肝癌细胞铁死亡的影响及作用机制研究

Study on Effects and Mechanism of Mollugin in Ferroptosis in Hepatocellular Carcinoma Cells

目的 基于铁死亡通路探究大叶茜草素抑制肝细胞癌的作用机制。方法 体外培养肝癌HepG2细胞,根据IC50分为对照组、大叶茜草素低剂量组(10μmol/L)、大叶茜草素中剂量组(20μmol/L)和大叶茜草素高剂量组(40μmol/L),CCK-8法检测细胞活力,乳酸脱氢酶(LDH)试剂盒检测细胞毒性,克隆形成实验观察细胞克隆能力,检测细胞谷胱甘肽(GSH)、丙二醛(MDA)、活性氧(ROS)、超氧化物歧化酶(SOD)、超氧化物、脂质过氧化物含量及线粒体膜电位(MMP),Western blot检测细胞铁死亡抑制蛋白1(FSP1)、GTP环化水解酶1(GCH1)、二氢乳清酸脱氢酶(DHODH)、谷胱甘肽过氧化物酶(GPX)4蛋白表达,RT-qPCR检测FSP1、DHODH、GCH1、GPX4 mRNA表达。在过表达和沉默GPX4条件下观察大叶茜草素对HepG2细胞活力和GSH、MDA含量的影响。结果 中、高剂量大叶茜草素可减少HepG2细胞克隆形成数目,降低细胞GSH含量和SOD活性,升高MDA、超氧化物、脂质过氧化物和ROS含量,降低MMP(P<0.001)。大叶茜草素干预对HepG2细胞FSP1、GCH1、DHODH蛋白和mRNA表达无显著影响,可降低GPX4蛋白和m RNA表达(P<0.001),过表达和沉默实验验证GPX4是大叶茜草素调控铁死亡的核心靶点。结论 大叶茜草素主要通过调节GPX4介导的铁死亡发挥抗肝细胞癌作用。

Objective To investigate the mechanism of inhibitory effect of mollugin on hepatocellular carcinoma based on the ferroptosis pathway.Methods HepG2 cells were cultured in vitro and divided into control group,mollugin low-(10μmol/L),medium-(20μmol/L),and high-dosage(40μmol/L)groups based on the inhibitory concentration of 50%.The cell viability was detected by CCK-8 method,cytotoxicity was detected by LDH kit,and the ability of cell colony formation was observed by clone formation assay,the contents of GSH,MDA,ROS,SOD,superoxide,lipid peroxide and MMP were detected,the protein expression of ferroptosis suppressor protein 1(FSP1),GTP cyclohydrolase 1(GCH1),dihydroorotate dehydrogenase(DHODH)and glutathione peroxidase 4(GPX4)were detected by Western blot,the mRNA expression of FSP1,DHODH,GCH1 and GPX4 were detected using RT-qPCR.The effect of mollugin on cell viability and GSH,MDA contents of hepatocellular carcinoma cells were observed under overexpression and silencing of GPX4 by mollugin.Results The medium-and high-dose of mollugin could reduce the number of clone formation in HepG2 cells,decrease the GSH content and SOD activity of cells,increase the content of MDA,superoxide,lipid peroxides and ROS,and decreased MMP(P<0.001).The intervention of mollugin had no significant effect on the expressions of FSP1,GCH1,DHODH protein and mRNA in HepG2 cells,but could decrease the expression of GPX4 protein and mRNA(P<0.001).Overexpression and silencing experiments confirmed that GPX4 was the core target for the regulation of ferroptosis by mollugin.Conclusion Mollugin mainly exerts its anti-liver cancer effect by regulating GPX4 mediated ferroptosis.