Guizhi Fuling Capsule ameliorates endometrial hyperplasia through promoting p62-Keap1-NRF2-mediated ferroptosis

Guizhi Fuling Capsule (GFC) is a classical traditional Chinese medicine officially recorded in Synopsis of the Golden Chamber and has long been used to treat gynecological diseases in China. However, scientific evidence for the anti-endometrial hyperplasia potential of GFC used in traditional medicine is lacking. This study evaluated whether GFC protects against endometrial hyperplasia and its potential mechanism in mice. We used estrogen (estradiol) to induce endometrial hyperplasia in mice. C57BL/6 mice were treated with estradiol subcutaneously for 21 days, and GFC (75 mg/kg and 150 mg/kg) was given intragastric administration from the first day of the modeling. H&E staining is used to evaluate endometrial tissue structure change. Malondialdehyde was measured to explore lipid peroxidation. Western blot, immunohistochemistry and immunofluorescence were performed to observe the expressions of GPX4, p62, Keap1 and NRF2. The degree of ferroptosis in endometrial tissue of patients with endometrial hyperplasia was lower than normal endometrial tissue. In addition, ferroptosis inducer imidazole ketone erastin could improve endometrial hyperplasia in mice. Interestingly, GFC significantly alleviated endometrial hyperplasia through triggering ferroptosis. Furthermore, GFC inhibited p62-Keap1-NRF2 pathway in estradiol-induced endometrial hyperplasia model. GFC may attenuate estrogen-induced endometrial hyperplasia in mice through triggering ferroptosis via inhibiting p62-Keap1-NRF2 pathway. These findings suggest that GFC might act as a promising traditional Chinese medicine to treat endometrial hyperplasia.