a, Workflow of kidney ischemia–reperfusion injury (IRI) model with pretreatment of AY9944 via intraperitoneal injection once daily for four times before IRI at the dose of 25 mg/kg. b, Levels of 7-DHC in kidneys of mice IRI model. n=7 in each group. c, d, The concentration of blood urea nitrogen (BUN) (c) and serum creatinine (SCr) (d) of mice kidney IRI model. n=7 in each group. e, f, Representative PAS staining (e) and quantification of renal damage (f) from mice kidney IRI model. n=6 in each group. Scale bar, 100 μm. g, h, Representative immunohistochemical staining (g) and quantification (h) of 4-HNE in kidneys from mice IRI model. n=6 in each group. Scale bar, 100 μm. For b-h, data are representative of two independent experiments and data plotted are mean ± s.e.m., statistical analysis was performed two-way ANOVA, ***P < 0.001, ****P < 0.0001.