Objective To explore the role and mechanism of puerarin in ameliorating acetaminophen(APAP)-induced acute liver injury in mice based on ferroptosis signaling pathway.Methods Twenty-four C57BL/6J mice were randomly divided into normal group,model group,and puerarin low-and high-dose groups(50 and 200 mg·kg-1),6 mice in each group;all the administration groups were given continuous gavage(10 mL·kg-1)once a day pre-dosed for 3 days.One hour after the last dose,APAP(300 mg·kg-1)was intraperitoneally injected into the mice of the model group and the puerarin low-and high-dose groups to replicate the drug-induced liver injury(DILI)mouse model.After 24 hours,the serum levels of alanine transaminase(ALT),aspartate aminotransferase(AST),and lactate dehydrogenase(LDH)were measured by the microplate assay;HE staining was used to observe the histopathological changes in liver tissue;the apoptosis of hepatocytes was observed by the TUNEL staining assay;the levels of malondialdehyde(MDA)were measured by the TBA assay;the mRNA expression levels of reactive oxygen species(ROS),4-hydroxynonenal(4-HNE),glutathione peroxidase 4(GPX4),and solute carrier family 7 member 11(SLC7A11)were detected by immunofluorescence;qRT-PCR was performed to measure the mRNA levels of ferroptosis-related genes GPX4,transferrin receptor(TFRC),and solute carrier family 11 member 2(SLC11A2)in liver tissue.Results Compared with the normal group,the serum ALT,AST,and LDH levels of mice in the model group were significantly elevated(P＜0.01);the liver lobules showed obvious damage,with swelling and rupture of hepatocytes,cytoplasmic vacuolisation,fragmentation of nuclei,congestion of the hepatic blood sinusoids and infiltration of inflammatory cells,and an increase in apoptotic cells;the level of MDA in the hepatic tissues was significantly elevated(P＜0.05);the red fluorescence(positive expression)of ROS and 4-HNE was significantly enhanced(P＜0.05,P＜0.01),and the red fluorescence(positive expression)of GPX4 and SLC7A11 was significantly weakened in liver tissue(P＜0.01);the mRNA expressions of GPX4 and SLC11A2 in liver tissue were significantly down-regulated(P＜0.05),and there was a tendency for the down-regulation of TFRC expression but the difference was not statistically significant(P＞0.05).Compared with the model group,the serum AST and LDH levels of mice in the low-and high-dose groups of puerarin were significantly reduced(P＜0.05,P＜0.01),and there was a decrease in serum ALT,but the difference was not statistically significant(P＞0.05);the structure of the liver lobules was clearer,with radial arrangement of hepatic cords,and the area of necrotic liver tissue and apoptotic cells were significantly reduced;the level of MDA in the liver tissue was significantly reduced(P＜0.05);the red fluorescence(positive expression)of ROS and 4-HNE in liver tissue were significantly attenuated(P＜0.05,P＜0.01).The red fluorescence(positive expression)of GPX4 and SLC7A11 in liver tissue of the mice in the puerarin low-dose group were significantly enhanced(P＜0.05,P＜0.01),and there was a tendency to enhance the red fluorescence(positive expression)of GPX4 and SLC7A11 in the liver tissue of the mice in the puerarin high-dose group,but the difference was not statistically significant(P＞0.05).The mRNA expressions of GPX4 and TFRC in liver tissue of mice in low-dose puerarin group was significantly up-regulated(P＜0.05),while the mRNA expressions of GPX4 and SLC11A2 in high-dose puerarin group were significantly up-regulated(P＜0.05).Conclusion Puerarin had a significant protective effect on APAP-DILI,which may be related to its inhibition of cellular ferroptosis through the SLC7A11/GPX4 pathway.