Parthenolide attenuated the endometriosis-like lesions by activating autophagy and suppressing NLRP3 inflammasome activity.

[OBJECTIVES] Parthenolide (PTL) has significant anti-inflammatory and immunomodulatory effects, but its regulatory mechanisms in endometriosis (EMs) remain unclear. This study aimed to systematically evaluate the effects of PTL on cellular models and a murine EMs model, with a focus on its regulatory roles in autophagy and the NLRP3 inflammasome pathway.

[MATERIALS AND METHODS] Human monocytic leukemia THP-1 cells, murine immortalized bone marrow-derived macrophages, and 30 female C57BL/6 mice were used. Autophagy-related proteins (Beclin1, LC3, p62) and inflammasome components (NLRP3, ASC, caspase-1) were detected by Western blotting, and the activation of the AMPK/ULK1 signaling pathway was assessed after treating with PTL at a concentration of 10 mg/ml for 1 hr. A murine EMs model was established by peritoneal implantation, followed by intraperitoneal injections of PTL (10 mg/ml). Immunohistochemical staining was performed to detect the expression of NLRP3, caspase-1, IL-1β, and GSDMD in ectopic lesions.

[RESULTS] , PTL (10 mg/ml) significantly inhibited the activation of NLRP3, caspase-1-p20, IL-1β, and GSDMD, while increasing the phosphorylation levels of Beclin1 and AMPK/ULK1, and decreasing the expression of p62 and LC3, indicating enhanced autophagic flux. , PTL treatment markedly reduced the number, surface area, and weight of ectopic lesions in mice, and significantly suppressed the expression of inflammatory proteins in the lesions.

[CONCLUSION] PTL exerts its therapeutic effect on EMs by simultaneously activating autophagy through the AMPK/ULK1 signaling pathway and inhibiting the NLRP3 inflammasome and its downstream effectors.