Abstract: Objective To investigate the role of Ferrostatin-1(Fer-1) in high glucose-induced ferroptosis of renal tubular epithelial cells. Method (1) 24 DBA/2J mice were randomly divided into 4 groups: normal control group, Fer-1 intervention group, DM model group, DM + Fer-1 intervention group with 6 mice in each group. According to the body weight of mice, DBA/2J mice were injected intraperitoneally with freshly prepared Streptozocin at a dose of 40 mg / kg for 5 days to establish DM model. Fer-1 intervention group and DM+Fer-1 intervention group were given intraperitoneal injection of Fer-1 (2.5μmol/kg) every day for 12 weeks after modeling.. The control group and DM Group were intraperitoneally injected with the same volume of normal saline for 12 weeks. The expression levels of activated glutathione peroxidase 4(GPX4)and solute carrier family 7 A11(SLC7A11)were detected by Western blotting, and the expression and localization of GPX4 in renal tissue were detected by immunohistochemistry.(2) Human renal tubular epithelial cells (HK-2) were stimulated with high glucose (30 mmol/L) , and treated with 200 nm Fer-1. The expression of ferroptosis signaling in renal tubular epithelial cells was detected by Western blotting and immunofluorescence staining. Results  Compared with the normal control group, the levels of Fe2+and Malondialdehyde (MDA) in the kidney of DM model group were significantly up-regulated, glutathione (GSH) was significantly down-regulated ( t=35.073、15.732 and 4.954 respectively，all P ＜ 0.001) , and the protein expression levels of GPX4 and SLC7A11, which were related to ferroptosis, were significantly up-regulated (t=12.432 and 5.484；P=0.006 and 0.003) . Compared with the DM model group, the levels of Fe2+ and MDA in the kidney of DM +Fer-1 intervention group were down-regulated, while GSH was up-regulated (t=14.503、4.675 and 7.124； all P＜0.001) . The protein expression levels of GPX4 and SLC7A11 were up-regulated (t =4.573 and 27.942；P= 0.039 and 0.001) . In addition, high glucose could induce the expression levels of ferroptosis related proteins GPX4 and SLC7A11 in HK-2 cells cultured in vitro to decrease significantly ( t=12.433 and 7.716；P=0.006 and 0.019) , the expression levels of GPX4 and SLC7A11 were significantly increased by Fer-1(t=5.136 and 5.043；P=0.035 and 0.037) . Conclusions  Inhibition of ferroptosis in renal tubular epithelial cells induced by high glucose may be a new strategy to prevent the progression of DM.

Key words: Ferroptosis, Diabetic kidney disease, Renal tubular epithelial cells, Ferrostatin-1