Electroacupuncture ameliorates endometriosis-associated ovarian dysfunction by activating the Nrf2 pathway to upregulate GPX4 function and inhibit ferroptosis

In brief: Iron overload-induced ferroptosis contributes to ovarian damage in endometriosis, yet effective interventions are lacking. This study shows that electroacupuncture preserves ovarian function by activating the nuclear factor erythroid 2-related factor 2 antioxidant pathway to inhibit ferroptosis. Abstract: Endometriosis (EMs) is a common cause of ovarian dysfunction and infertility, closely linked to iron overload-induced oxidative stress and ferroptosis. While electroacupuncture (EA) has shown promise in treating reproductive disorders, its role in regulating ovarian ferroptosis in EMs remains unclear. This study aimed to investigate the protective effects and underlying mechanisms of EA on ovarian function in a mouse model of EMs, which simulated the chronic pelvic hemorrhage observed in patients. Comprehensive evaluations were performed using hematoxylin-eosin staining, quantitative real-time PCR, western blot, immunohistochemistry, immunofluorescence, and biochemical assays to assess ovarian function, iron metabolism, oxidative stress, and ferroptosis-related markers. The results demonstrated that EA treatment significantly restored estrous cyclicity, increased ovarian weight and index, improved serum hormone levels, promoted multi-stage follicular development, and reduced follicular atresia. EA also alleviated ovarian iron overload and oxidative stress. Mechanistically, EA activated the nuclear factor erythroid 2-related factor 2 pathway and its downstream targets, upregulated the anti-ferroptotic protein glutathione peroxidase 4, suppressed the pro-ferroptotic factor long-chain acyl-CoA synthetase 4, and consequently reduced lipid peroxidation. In conclusion, this study reveals that EA mitigates granulosa cell ferroptosis and ameliorates EMs-induced ovarian injury by activating nuclear factor erythroid 2-related factor 2 to enhance glutathione peroxidase 4 activity and inhibit long-chain acyl-CoA synthetase 4-mediated lipid peroxidation. These findings provide experimental evidence supporting EA as a potential complementary therapy for EMs-related infertility.