The effect of norepinephrine on ovarian dysfunction by mediating ferroptosis in mice model.

Studies have shown that stress is associated with ovarian dysfunction. Norepinephrine (NE), a classic stress hormone involved in the stress response, is less recognized for its role in ovarian function. In this study, an NE-treated mouse model is induced by intraperitoneal injection of NE for 4 weeks. Compared with normal control mice, NE-treated mice show disturbances in the estrous cycle, decreased levels of anti-Mullerian hormone (AMH) and estradiol (E2), and increased level of follicle-stimulating hormone (FSH). Additionally, the numbers of primordial follicles, primary follicles, secondary follicles, and antral follicles are decreased, whereas the number of atretic follicles is increased in NE-treated mice, indicating NE-induced ovarian dysfunction. RNA sequencing further reveals that genes associated with ferroptosis are significantly enriched in NE-treated ovarian tissues. Concurrently, the levels of reactive oxygen species (ROS), ferrous ions, and malondialdehyde (MDA) are increased, whereas the expression level of glutathione peroxidase 4 (GPX4) is decreased. To elucidate the mechanism of NE-induced ferroptosis in ovaries and the potential reversal by Coenzyme Q10 (CoQ10), an antioxidant, we conduct both in vitro and in vivo experiments. In vitro, the granulosa cell line KGN, when treated with NE, shows decreased cell viability, reduced expression of GPX4, elevated levels of ferrous ion and ROS, and increased MDA level. However, these NE-induced changes are reversed by the addition of CoQ10. Compared with the NE group, the NE-treated mice supplemented with CoQ10 present increased GPX4 level and decreased iron, ROS, and MDA levels. Moreover, the differential expression of genes associated with ferroptosis induced by NE is ameliorated by CoQ10 in NE-treated mice. Additionally, CoQ10 improves ovarian function, as evidenced by increased ovarian weight, more regular estrous cycles, and an increase in follicles at various stages of growth in NE-treated mice. In conclusion, NE induces ovarian dysfunction by triggering ferroptosis in ovarian tissues, and CoQ10 represents a promising approach for protecting reproductive function by inhibiting ferroptosis.