Ge-Gen Decoction Exerts an Anti-Primary Dysmenorrhea Effect in Rats by Inactivating the HSP90/NLRP3/NF-κB/COX-2 Pathway.

Objective: Although Ge-Gen decoction (GGD) has beneficial effects on primary dysmenorrhea (PD), the underlying mechanisms remain poorly understood. Our previous proteomic data revealed decreased level of heat shock protein 90 (HSP90) in uterine tissues of rats with PD after GGD treatment. However, the potential role of HSP90 in the anti-PD effect of GGD and the underlying mechanisms remain unexplored. This study investigated the potential role and mechanism of HSP90 in the anti-PD effect of GGD using a PD rat model.

Methods: Wistar female rats were used to investigate the potential role of HSP90 in the anti-PD effect of GGD. The rat PD model was established by injecting estradiol benzoate and oxytocin. GGD, Terazosin (an agonist of HSP90) or GGD combined with Terazosin were orally administered to the PD rats. The expression levels of protein and cytokines, including HSP90, nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), nuclear factor kappa B (NF-κB) and cyclooxygenase-2 (COX-2) in the uterine tissue of rats in each group were detected by immunohistochemical assay or Western blot.

Results: GGD ameliorated the writhing response, suppressed the protein levels of HSP90 and inflammation-associated proteins, including NLRP3, NF-κB, and COX-2 in uterine tissues of rats with PD. Terazosin attenuated the anti-PD effect of GGD and reversed the effects of GGD on the protein levels of NLRP3, NF-κB and COX-2 in uterine tissues.

Conclusion: GGD exerts an anti-PD effect and suppresses levels of HSP90 and some inflammation associated proteins in uterine tissues of rats.