Paeonol alleviates acetaminophen-induced acute liver injury partly through Nrf2/HO-1/GPX4 signaling pathways

Acetaminophen (APAP) overdose often leads to drug-induced acute liver injury (ALI), characterized by ferroptosis, an iron-dependent form of cell death associated with lipid peroxide (LPO) accumulation. Although paeonol (PAE) is known for its hepatoprotective and antioxidant properties, the effects of PAE on APAP-induced hepatocyte apoptosis and ferroptosis are not well understood. In the current study, male Kunming mice were pretreated with PAE at doses of 30, 60, or 120 mg/kg for 7 days before receiving APAP at 300 mg/kg. Mice were sacrificed 24 h post-APAP injection, and liver tissue and serum were analyzed. In vitro, LO2 cells were exposed to APAP (10 mmol/L) to induce hepatic injury. The effects of PAE and ferrostatin-1 were assessed using histopathological, TUNEL, immunofluorescence staining, reactive oxygen species, JC-1 staining, V-FITC/PI, transmission electron microscopy, western blotting and biochemical assays. In vivo study showed that PAE reduced APAP-induced liver histopathological abnormalities, serum aminotransferase levels, and hepatocyte apoptosis. PAE pretreatment also lowered hepatic malondialdehyde and LPO contents while increasing superoxide dismutase, catalase, and glutathione levels. In vitro study indicated that PAE and ferrostatin-1 mitigated APAP-induced LO2 cells apoptosis through inhibiting mitochondrial dysfunction and oxidative injury. PAE treatment increased the expression levels of Nrf2, HO-1 and GPX4 both in vivo and in vitro. In conclusion, PAE appears to protect against APAP-induced ALI by inhibiting ferroptosis-related LPO accumulation through the Nrf2/HO-1/GPX4 signaling pathways.