α-亚麻酸植物甾醇酯调控Nrf2/GPX4信号通路抑制HepG2细胞铁死亡

PLANT STEROL ESTER OFα-LINOLENIC ACID INHIBITES FERROPTOSIS OF HepG2CELLS VIA REGULATING Nrf2/GPX4 SIGNALING PATHWAY

目的探讨α-亚麻酸植物甾醇酯(PS-ALA)对油酸与铁死亡诱导剂(OA/erastin)联合诱导的HepG2细胞铁死亡的改善作用,并基于Nrf2/GPX4信号通路进一步探索其潜在分子机制。方法采用1mmol的OA和10μmol的erastin联合诱导HepG2细胞发生铁死亡,同时给予ALA、PS和PS-ALA干预。油红O染色观察HepG2细胞脂肪变性程度;Hoechst/PI双染评价铁死亡发生;蛋白免疫印迹检测铁死亡相关蛋白Nrf2、GPX4、HO-1、NQO1及ptgs2的表达水平;荧光探针检测细胞内ROS与脂质过氧化物水平。结果与Control组相比,OA/erastin组细胞内有大量脂质沉积,ROS和脂质过氧化物显著增多,发生明显铁死亡。PS-ALA干预显著减轻OA/erastin诱导的HepG2细胞脂质沉积、减少细胞ROS与脂质过氧化物产生,抑制铁死亡。进一步的分子机制研究表明PS-ALA显著上调HepG2细胞Nrf2及其靶基因GPX4、HO-1与NQO1的蛋白表达水平。结论PS-ALA能有效抑制OA/erastin诱导的HepG2细胞铁死亡,其分子机制可能与上调Nrf2/GPX4通路有关。

Objective To investigate the ameliorative effect of plant sterol ester ofα-linolenic acid(PS-ALA)on ferroptosis of HepG2 cells induced by oleic acid and ferroptosis inducer(OA/erastin)and further explore the potential molecular mechanism based on Nrf2/GPX4 signaling pathway.Methods The ferroptosis of HepG2 cells were induced by the combination of 1mmol OA and 10μmol erastin and intervened with ALA,PS,and PS-ALA.The degree of hepatocyte steatosis was observed by Oil red O staining.The occurrence of ferroptosis was assessed by Hoechst/PI staining.The expression levels of ferroptosis-related proteins(Nrf2,GPX4,HO-1,NQO1,and ptgs2)were detected by Western blot.ROS and lipid peroxides were detected by fluorescence probe.Results Compared with the control group,the OA/erastin group showed significant lipid deposition,excessive ROS,a lot of lipid peroxides,and obvious ferroptosis.PS-ALA treatment significantly inhibited OA/erastin-induced lipid deposition,ROS and lipid peroxides production,and ferroptosis in HepG2cells.Further molecular mechanism studies showed that PS-ALA significantly up-regulated the protein expression levels of Nrf2 and its targeted genes GPX4,HO-1,and NQO1 in HepG2 cells.Conclusion PS-ALA can effectively inhibit OA/erastin-induced ferroptosis in HepG2 cells,and its molecular mechanism is related to up-regulated Nrf2/GPX4 signaling pathway.[ACTA NUTRIMENTA SINICA,2023,45(1):63-69]