USP8 modulates primary ovarian insufficiency through regulation of Beclin1-dependent autophagy-induced ferroptosis.

The premature exhaustion of primordial follicles is a characteristic of primary ovarian insufficiency (POI), represents a profound disorder of ovarian function that leads to infertility, substantial impairments in daily activities, and enduring health risks. Despite its clinical significance, the underlying mechanisms of POI remain largely elusive. In this study, we investigated the potential role of ferroptosis, a form of programmed cell death associated with iron accumulation and lipid peroxidation, in the pathogenesis of POI.Our findings revealed a marked upregulation of USP8 expression in POI cases compared to controls. To further explore the functional significance of this observation, we manipulated USP8 expression in granulosa cells, a key cell type in ovarian function. Overexpression of USP8 resulted in a decrease in glutathione (GSH) levels, reduced cell viability, an increase in lipid peroxidation, iron accumulation, and ultimately, the induction of ferroptosis. Conversely, knockdown of USP8 significantly inhibited these ferroptotic processes, suggesting a critical role for USP8 in regulating ferroptosis in granulosa cells. Mechanistically, we demonstrated that USP8 stabilizes the Beclin1 protein by preventing its ubiquitination and subsequent degradation. This stabilization of Beclin1 promotes autophagy, which in turn facilitates ferroptosis. In conclusion, our study reveals that USP8 plays a pivotal role in the development of premature ovarian insufficiency by stimulating autophagy-dependent ferroptosis through the deubiquitination and stabilization of Beclin1. These discoveries not only improve our knowledge of the molecular processes behind POI but also pave the way for the creation of tailored treatments for POI and other ovarian function-related conditions.