Ferroptosis is a new mode of cell death, which is characterized by inducing the accumulation of lipid peroxides dependent on iron ions and reactive oxygen species. It has been found that ferroptosis can lead to follicle atresia by promoting granulosa cell death and increasing its reactive oxygen species content, but the specific mechanism has not been elucidated. Through transcriptome sequencing, we found that ferroptosis markers and related genes were upregulated in porcine atretic follicles. PTGS2 was found to be differentially expressed between atretic and healthy follicles. By inhibiting NF-κB nuclear translocation, inhibition of the PTGS2 gene expression reduced the degree of ferroptosis in granulosa cells and rescued granulosa cell death and oxidative stress caused by ferroptosis. Therefore, we propose that the NF-κB/PTGS2 axis plays a key role in ferroptosis-induced granulosa cell death, leading to follicular atresia. Melatonin, a neurohormone secreted by the pineal gland of the upper thalamus, is involved in the regulation of various metabolic, immune, reproductive, and other processes. In the ferroptosis treatment group, melatonin treatment alleviated the degree of ferroptosis (downregulation of ferroptosis marker genes and markers) and decreased the expression of PTGS2. In summary, we have demonstrated that melatonin inhibits ferroptosis via the NF-κB/PTGS2 axis in granulosa cells.

Granulosa cell ferroptosis is a critical factor in follicular atresia and premature ovarian insufficiency (POI). As a regulated form of programmed cell death, ferroptosis is gaining significant attention in reproductive medicine research. MicroRNAs (miRNAs) play a crucial role in regulating key aspects of ferroptosis, including the glutathione-GPX4 pathway, glutamate/cystine transport, and iron and lipid metabolism. The present study demonstrates that miR-26a positively modulates ferroptosis by targeting SLC7A11, a member of the solute carrier family. We found that oocytes and granulosa cells are susceptible to the ferroptosis inducer erastin, and employed RNA sequencing to delineate the miRNA expression profiles during erastin-induced damage and ferroptosis. Notably, miR-26a expression was significantly upregulated in erastin-treated oocytes. Importantly, overexpression of miR-26a promoted ferroptosis in granulosa cells, while its knockdown inhibited this process. Ectopic miR-26a expression suppressed SLC7A11, thereby increasing ferroptosis. Our findings indicate that miR-26a influences ferroptosis by inhibiting glutathione synthesis, reducing cellular antioxidant capacity, and suggesting a potential strategy to enhance reproductive potential.