E3 ubiquitin ligase PELI1 promotes ferroptosis in granulosa cells in PCOS by degrading Fth1

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease in women of reproductive age, characterized by hyperandrogenemia and obstruction of ovulation. However, the underlying mechanisms of ovarian abnormalities in PCOS remain to be investigated. In this study, we first identified altered levels of ovarian ferroptosis in the PCOS population by screening a web-based database. Further, we established a prasterone-exposed PCOS mouse model and a granulosa cell model to confirm that hyperandrogenism can lead to the development of ferroptosis in ovarian granulosa cells. The transcriptome sequencing and cellular experiments were conducted to explore the possible mechanisms. It was found that the ubiquitination pathway and P53 pathway are significantly enriched in the prasterone-exposed granulosa cells. The E3 ubiquitin ligase PELI1 gene is significantly highly expressed in PCOS ovaries and may contribute to ferroptosis by degrading FTH1. In addition, high expression of the P53 gene was associated with alterations in PELI1/FTH1. This study confirmed that hyperandrogenism can mediate the development of ovarian ferroptosis via the P53/PELI1/FTH1 pathway and the E3 ubiquitin ligase PELI1 plays an important regulatory role. In vivo, the iron death inhibitor deferoxamine mesylate could alleviate ferroptosis and follicular development disorder in the ovaries of PCOS mice. This study provides new insights into the pathological changes of PCOS ovaries and possible interventions for the treatment of PCOS.