RUNX1-BNIP3-mediated mitophagy regulates hepatocyte ferroptosis by promoting SLC25A28 degradation

Lambda-cyhalothrin (LCT), a commonly used pyrethroid insecticide, has been increasingly considered as a possible risk factor for liver injury. Ferroptosis, a form of regulated cell death resulting from the accumulation of iron and lipid peroxidation, is identified by mitochondrial dysfunction, but its mechanisms underlying LCT-induced liver damage remain poorly defined. Runt-related transcription factor 1 (RUNX1) isa transcription factor involved in diverse developmental and stress-responsive processes, yet its role and regulation in xenobiotic-induced liver injury remain unclear. Here, we investigated whether RUNX1-BNIP3-mediated mitophagy links mitochondrial iron homeostasis to ferroptosis-associated liver injury following LCT exposure. We showed that LCT exposure induced structural and functional liver injury accompanied by ferroptosis, impaired autophagic flux, and defective BNIP3-mediated mitophagy. Mechanistically, LCT suppressed RUNX1 expression, resulting in decreased BNIP3 transcription and consequently compromising mitophagic clearance of the mitochondrial iron importer SLC25A28. The resulting iron accumulation, glutathione imbalance and lipid peroxidation could contribute to ferroptosis and accelerate hepatocellular senescence. Of note, RUNX1 or BNIP3 overexpression efficiently restored mitophagy and promoted SLC25A28 turnover, thereby suppressing ferroptosis and cellular senescence. However, these benefits were abolished by BNIP3 knockdown or SLC25A28 overexpression. The results further identified SLC25A28 as an important downstream mediator of BNIP3-mediated mitophagy. Together, these findings identify that RUNX1 represents an important regulatory factor involved in LCT-induced liver injury by regulating BNIP3-dependent mitophagy and facilitating SLC25A28 turnover, thereby inhibiting ferroptosis and attenuating hepatocellular senescence. Our study uncovers that modulation of the hepatic RUNX1-BNIP3-SLC25A28 axis may represent a potential strategy for mitigating LCT-induced liver injury.