Honghe Fujie lotion ameliorates pregnancy-associated vulvovaginal candidiasis in mice by inhibiting the activation of NLRP3 inflammasome.

Vulvovaginal candidiasis, a common infection of the female reproductive tract, poses heightened risks when occurring during pregnancy. Although Honghe Fujie lotion (HFL), a traditional Chinese medicine, is clinically used for mycotic vaginitis, its therapeutic efficacy and mechanisms in pregnancy-associated vulvovaginal candidiasis (pVVC) remain unclear. In this study, HPLC-MS was used to analyze and identify the compounds in HFL. This study investigated HFL's effects through in vitro and in vivo approaches. A murine model of vaginal Candida albicans (C. albicans) infection was established to evaluate the therapeutic effect of HFL on pVVC. Vaginal fungal load was quantified by analyzing vaginal lavage fluid, while the impact of HFL on adverse pregnancy outcomes was assessed through placental developmental analysis. Furthermore, the effects of HFL on pVVC-induced vaginitis and NLRP3 inflammasome activation were examined using immunofluorescence, enzyme-linked immunosorbent assay, and western blot. The results included: (1) High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) analysis identified 545 chemical constituents in HFL. (2) HFL significantly inhibited C. albicans growth and biofilm metabolic activity in vitro; (3) in a murine pVVC model, HFL reduced vaginal fungal load and mitigated adverse pregnancy outcomes, while also restoring trophoblast cell distribution in placental tissues; (4) mechanistically, HFL suppressed NLRP3 inflammasome activation, leading to Caspase-1 activity downregulation and subsequent impairment of pro-inflammatory cytokine secretion. These findings demonstrate that HFL alleviates pVVC by targeting the NLRP3 signaling pathway, providing a preclinical foundation for its therapeutic application in pregnancy-associated VVC.