Ferroptosis-induced effect and mechanism of dihydroartemisinin on tumor cells / 中草药

ABSTRACT

Objective: To explore the effect and mechanism of dihydroartemisinin (DHA) in inducing ferroptosis of tumor cells. Methods: 3,3',5,5'-Tetramethylbenzidine was used to detect the oxygen free radicals (•OH) formed by DHA and FeSO4 in vitro. The cytotoxicity of DHA on HepG2 cells was detected by MTT method (including FeSO4 or deferoxamine pretreated groups). MTT assay was used to investigate the influence of glutathione (GSH) and inhibitor (Fer-1) on cytotoxicity of DHA; DCFH-DA dye was used to investigate intracellular reactive oxygen species induced by DHA (including FeSO4 pretreated groups). C11-BODIPY581/591 and DiO dye were used to examine the influence of DHA (including FeSO4 pretreated groups) on intracellular lipid peroxide formation and cell membrane structure; Glutathione peroxidase assay kit was used to explore the influence of DHA (including FeSO4 pretreated groups) on intracellular activity GPX-4 in HepG2 cells. Results: Fenton-like reaction occurred between DHA and Fe2+, and •OH was produced during the reaction. The half-inhibitory concentration (IC50) of DHA was (39.96 ± 8.78) μmol/L. FeSO4 and deferoxamine could increase or decrease the cytotoxicity of DHA, respectively. After treated with DHA, the intracellular content of reactive oxygen species and lipid peroxide was increased, the cell morphology became larger, and the cell membrane was broken. Compared with the DHA treated group, the FeSO4 pretreated group further increased the intracellular reactive oxygen species and lipid peroxide content, and the cell membrane morphology was completely destroyed. FeSO4 could also enhance the inhibitory effect of DHA on GPX-4 activity. Conclusion: DHA increases intracellular reactive oxygen species through Fenton-like reaction and ultimately induces ferroptosis of tumor cells. In addition, exogenous iron can accelerate the Fenton-like reaction of DHA and accelerate the occurrence and development of ferroptosis of tumor cells.