ER stress-mediated ferroptosis in granulosa cells contributes to follicular dysfunction of PCOS driven by hyperandrogenism

Abstract

Research question: Does hyperandrogenism affect ovarian granulosa cells(GCs) function through activation of ferroptosis? Is hyperandrogen-induced ferroptosis regulated by endoplasmic reticulum(ER) stress?Design: The aim of this study was to investigate the potential mechanism underlying follicular dysfunction induced by hyperandrogenaemia.Results: First, activation of ferroptosis and ER stress were observed in GCs of patients with PCOS undergoing in vitro fertilization/Intracytoplasmic sperm injection(ICSI) treatment. Similar activation was observed in ovaries of PCOS-like mice induced by dehydroepiandrosterone. Subsequently, KGN cells were cultured in vitro with testosterone and ferrostatin-1 (Fer-1), an inhibitor of ferroptosis, to elucidate the potential mechanism associated with excessive induction of ferroptosis in GCs related to PCOS. Our findings demonstrated that testosterone treatment results in elevation of oxidative stress levels, particularly lipid peroxidation, and intracellular iron accumulation in GCs. The expression of genes and proteins associated with factors related to ferroptosis, mitochondrial membrane potential, and ultrastructure was investigated; the results showed that testosterone activated ferroptosis, whereas Fer-1 reversed these alterations. In addition, during in vitro experiments, activation of ER stress induced by testosterone treatment was detected in GCs. Tauroursodeoxycholate(TUDCA), an inhibitor of ER stress, significantly mitigated testosterone-induced ferroptosis in GCs.Conclusions: Our findings suggest that ferroptosis plays a part in reproductive injury mediated by hyperandrogens associated with PCOS and may be regulated by ER stress.