Rescuing fertility: C-Phycocyanin prevents ovarian damage through NRF2-mediated ferroptosis pathways in polycystic ovary syndrome models.

Polycystic ovary syndrome (PCOS), a common female endocrine disorder marked by disrupted folliculogenesis and hyperandrogenism, is increasingly linked to oxidative stress. Despite this association, the mechanistic basis remains poorly characterized. C-Phycocyanin (C-PC), a cyanobacteria-derived protein with potent antioxidant properties, has demonstrated therapeutic potential for treating PCOS, though the molecular pathways mediating its effects have yet to be delineated. This study employed both a dehydroepiandrosterone (DHEA)-induced murine model and DHEA-challenged human granulosa cells (KGN) to elucidate the regulatory role of C-PC. In vivo, oral administration of C-PC restored estrous cyclicity, reduced the prevalence of cystic follicles, and normalized circulating levels of testosterone, estradiol, progesterone, and luteinizing hormone (LH). In vitro, C-PC treatment activated the NRF2/xCT/GPX4 pathway, enhanced antioxidant activity, improved mitochondrial function, and suppressed ferroptotic death. Direct molecular interaction between C-PC and NRF2 was validated through molecular docking and cellular thermal shift assays (CETSA). Correspondingly, in vivo administration alleviated oxidative stress, inhibited ferroptosis, and increased GPX4 and xCT expression, effects reversed by pharmacological inhibition (ML385) and genetic silencing (AAV-sh-NRF2) of NRF2. C-PC also reduced DHEA-induced phosphorylation of AMPK, while co-treatment with an AMPK activator attenuated its effects on GPX4 and xCT, abolishing its anti-ferroptotic protection against granulosa cells. These findings suggest that C-PC mitigates PCOS pathology by repressing granulosa cell ferroptosis through coordinated activation of NRF2 and modulation of redox-sensitive AMPK signaling, highlighting its potential as a redox-targeted therapeutic strategy for PCOS.