Protective Effect of Hepcidin on Sepsis-Associated Acute Kidney Injury via Activating the Nrf2/GPX4 Signaling Pathway

Hepcidin not only sustains systemic iron homeostasis but also functions as an antimicrobial peptide. During this study, we sought to analyze the ability of hepcidin to protect against sepsis-associated acute kidney injury (SAKI) and elucidated its underlying mechanisms in mediating ferroptotic pathways. A SAKI mouse model was created via cecal ligation and puncture (CLP), along with an LPS-induced Human Kidney-2 (HK-2) cell model, to study the protective mechanism of hepcidin against SAKI. Through the analysis of renal injury biomarkers and ferroptosis-related molecules, combined with quantitative detection of nuclear factor-erythroid 2-related factor-2 (Nrf2) nuclear translocation and glutathione peroxidase 4 (GPX4), a regulatory protein of ferroptosis, we uncovered the hepcidin-mediated mechanisms underlying ferroptosis in SAKI. Hepcidin significantly attenuated renal function impairment in mice with SAKI and reduced the sepsis-driven increase in inflammatory mediators. As sepsis was associated with enhanced renal ferroptosis, hepcidin exerted a therapeutic effect by mitigating ferroptosis to a degree comparable with that of the ferroptosis inhibitor Ferrostatin-1 (Fer-1). Furthermore, hepcidin conferred renoprotective effects in SAKI by promoting the nuclear translocation of Nrf2, which in turn mediated the upregulation of the downstream anti-ferroptotic protein GPX4. Importantly, the Nrf2 inhibitor ML385 abrogated both the hepcidin-induced nuclear translocation of Nrf2 and the subsequent increase in GPX4 expression. Protective effects of hepcidin against SAKI are mediated by the Nrf2/GPX4 ferroptosis pathway, underscoring its therapeutic potential for SAKI.