NEDD4L facilitates granulosa cell ferroptosis by promoting GPX4 ubiquitination and degradation

BACKGROUND: Polycystic ovary syndrome (PCOS) is an androgen disorder and ovarian dysfunction disease in women of reproductive age. The cell death of granulosa cells (GCs) plays an important role in the development of PCOS. However, the mechanism of GC death is still unclear. METHODS: In the current study, NEDD4L was found to be elevated in PCOS GEO (Gene Expression Omnibus) databases and mouse models. The cell viability was analyzed by CCK-8 and FDA staining. The expression of ferroptosis markers was assessed by ELISA and immunofluorescence. The direct interaction of GPX4 and NEDD4L was verified by co-immunoprecipitation assay. RESULT: Functionally, results from CCK-8 and FDA staining demonstrated that NEDD4L inhibited the cell viability of KGN cells and NEDD4L increased the levels of iron, malonyldialdehyde, and reactive oxygen species and decreased glutathione levels. Moreover, the cell death of KGN induced by NEDD4L was blocked by ferroptosis inhibitor, suggesting that NEDD4L regulates KGN cell ferroptosis. Mechanistically, NEDD4L directly interacts with GPX4 and promotes GPX4 ubiquitination and degradation. CONCLUSION: Taken together, our study indicated that NEDD4L facilitates GC ferroptosis by promoting GPX4 ubiquitination and degradation and contributes to the development of PCOS.