Modified Erzhi pill inhibits ferroptosis of macrophages in atherosclerosis via DJ-1/GPX4 pathway
AIM:To investigate the effect of modified Erzhi pill(MEP)on macrophage ferroptosis in athero-sclerosis(AS),and to explore its mechanisms.METHODS:(1)Fifty apolipoprotein E gene knockout(ApoE-/-)mice were used to construct AS model and then randomly divided into model group,simvastatin group,and low-,medium-and high-dose MEP groups,with 10 mice in each group.Ten C57BL/6J mice with the same background were used as blank controls.After 10 weeks of intervention according to the grouping,HE staining was performed to observe the pathological changes of mouse aortic sinus tissues,and RT-qPCR was used to detect DJ-1 and glutathione peroxidase 4(GPX4)mRNA expression.(2)Forty SD rats were randomly divided into blank control group and MEP group to prepare MEP-containing serum.Mouse RAW264.7 macrophages were cultured,and divided into blank control serum group,oxidized low-density lipoprotein(ox-LDL)group,ferroptosis inhibitor(ferrostatin-1)group,MEP-containing serum group and MEP-containing serum + ferroptosis inducer(erastin)group.The effect of MEP-containing serum on cell viability was detected by MTT as-say.Oil red O staining was performed to observe lipid deposition in the cells.The levels of reactive oxygen species(ROS),malondialdehyde(MDA),total superoxide dismutase(SOD),glutathione(GSH)and iron ions in the cells were measured by ELISA.Transmission electron microscopy was used to observe the mitochondrial structure and morphology of the cells,and RT-qPCR and Western blot were used to detect the mRNA and protein expression of DJ-1,GPX4,solute carrier family 7 member 11(SLC7A11),ferritin heavy chain 1(FTH1),p53,prostaglandin-endoperoxide synthase 2/cy-clooxygenase 2(PTGS2/COX2)and NADPH oxidase 1(NOX1).RESULTS:(1)The MEP alleviated the formation of plaques at the root of the aortic sinus in mice and significantly increased the mRNA expression of DJ-1 and GPX4 in plaques.(2)Cellular lipid deposition was significantly increased by ox-LDL induction.The ROS,MDA and total SOD levels were significantly elevated,whereas the GSH level was significantly decreased.The mRNA and protein levels of p53,PTGS2/COX2 and NOX1 were significantly up-regulated,while the mRNA and protein levels of DJ-1,GPX4,SLC7A11 and FTH1 were significantly down-regulated.Compared with ox-LDL group,the cells in MEP-containing serum group showed a significant reduction of lipid deposition.Moreover,the levels of ROS,MDA and total SOD markedly de-creased,whereas the level of GSH significantly increased.The mRNA and protein levels of p53,PTGS2/COX2 and NOX1 were significantly down-regulated,while the mRNA and protein levels of DJ-1,GPX4,SLC7A11 and FTH1 were signifi-cantly up-regulated in MEP-containing serum group.CONCLUSION:The MEP can delay AS progression by inhibiting the ferroptosis of macrophages,and the mechanism may be related to the DJ-1/GPX4 signaling pathway.