Effect of butyl alcohol extract of Baitouweng Decoction on epithelial barrier of vaginal mucosa in mice with vulvovaginal candidiasis

Abstract

To investigate the effect of butyl alcohol extract of Baitouweng Decoction(BAEB) on the epithelial barrier of vaginal mucosa in mice with vulvovaginal candidiasis(VVC). Seventy-two female SPF Kunming mice were randomly divided into blank group, VVC model group, fluconazole group, and BAEB treatment groups(high, middle and low dose groups). Estradiol benzoate was injected subcutaneously qd alt, and Candida albicans(2×10~6 CFU·mL~(-1)) was inoculated into the vagina of mice during the pseudo estrus period for 7 days to construct a VVC model, followed by drug treatment for 7 days. Gram staining was used to observe the morphology of C. albicans in the vaginal secretions of mice; the amount of fungal load on the vaginal mucosa of mice was detected on agar plate; the pathological status of murine vaginal mucosa was observed by hematoxylin-eosin staining(HE); the integrity of mice vaginal mucosal epithelial barrier was observed by Masson's trichrome staining(MT), HE and periodic acid-schiff staining(PAS). Mucin-1 and mucin-4 protein expression levels of vaginal mucosal epithelial cells in mice were detected by immunohistochemistry; mucin-1 and mucin-4 protein expression levels on mucosal epithelial cells at 0 d, 3 d, and 7 d were determined by Western blot. The results showed that, in VVC model group, there were a large number of C. albicans hyphae and higher fungal load in vagina, within complete mucosal structure, cornified layer shed off, and the protein expression levels of mucin-1 and mucin-4 were significantly increased. After BAEB treatment, the hyphae in the vagina decreased; the fungal load decreased; the vaginal mucosal tissue damages were improved; the epithelial barrier was repaired, and mucin-1 and mucin-4 protein expression levels were down-regulated. The above results indicated that BAEB may play a role in the treatment of VVC by remodeling the integrity of the vaginal mucosal epithelial barrier.