Mechanistic studies on the regulation of ferroptosis by ferritin 1 through the FTH1 signaling pathway affecting oocyte maturation.

Ferrostatin-1 (FER-1) is a ferroptosis inhibitor that blocks lipid peroxidation; however, its role in porcine oocyte maturation remains unclear. This study assessed the effects and regulatory mechanisms of FER-1 on porcine oocyte maturation in vitro by regulating ferroptosis through the ferritin heavy chain 1 (FTH1) signaling pathway. A ferroptosis-induced injury model was established using ammonium ferric citrate (FAC), and a rescue model was established by adding FER-1. The cells were divided into four groups: control, FAC, FER-1, and FAC + FER-1. FTH1, Fe2+, and reactive oxygen species levels were analyzed using western blotting, FerroOrange fluorescent probe, and 2',7'-dichlorodihydrofluorescein diacetate, respectively. Mitochondrial membrane potential (MMP) and ferroptosis-related gene expression were assessed using 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide staining and real-time quantitative polymerase chain reaction, respectively. The FAC group exhibited significantly reduced oocyte maturation rate, FTH1 protein levels, MMP, and cleavage and blastocyst rates of in vitro-fertilized embryos, whereas Fe2+ and oxidative stress levels were significantly increased. Solute carrier family 7 member 11 (SLC7A11), FTH1, and glutathione peroxidase 4 (GPX4) levels were significantly reduced (P < 0.01), whereas acyl-CoA synthetase long-chain family member 4 (ACSL4) expression increased (P < 0.05). Co-treatment with FER-1 significantly increased oocyte maturation rates, FTH1 protein levels, and MMP, and cleavage and blastocyst rates of in vitro-fertilized embryos were significantly higher in the FAC + FER-1 group than in the FAC group, whereas Fe2+ and oxidative stress levels were significantly reduced. Additionally, SLC7A11, FTH1, and GPX4 mRNA levels were significantly increased (P < 0.05), and ACSL4 expression was significantly downregulated (P < 0.05). In summary, FER-1 may reduce ferroptosis in iron-overloaded mature oocytes through the FTH1 signaling pathway.