Inhibitory effect of Lacticaseibacillus paracasei VCare-360 on Candida albicans in mice with vaginal candidiasis.

BACKGROUND

Vaginal candidiasis (VC), mainly triggered by Candida species, ranks among the most‑common reproductive‑tract infections worldwide. Over‑utilization of antibiotics and antifungal medicines aggravates fungal drug‑resistance, which makes it imperative to explore novel alternative therapies. This work intended to investigate the anti‑Candida‑albicans activity of Lacticaseibacillus paracasei VCare‑360.

METHODS

The in‑vitro capacities of the strain to produce hydrogen peroxide and lactic acid and its antifungal activity were tested. A vaginal‑epithelial‑cell model was adopted to evaluate bacterial competitive adhesion and the regulation of pro‑inflammatory cytokine secretion. A mouse VC animal‑model was constructed to assess vaginal mucosal repair, inflammatory‑factor levels, myeloperoxidase activity, as well as vaginal and faecal microbiota composition after probiotic intervention.

RESULTS

L. paracasei VCare‑360 competed against C. albicans for vaginal‑epithelial‑cell adhesion and suppressed fungal colonization. It lowered the release of pro‑inflammatory cytokines in-vitro. In mice, this probiotic alleviated vaginal epithelial exfoliation, repaired damaged vaginal mucosa and relieved local inflammation (p < 0.05). It also decreased pro‑inflammatory cytokine concentrations and myeloperoxidase activity in blood and vaginal tissue. Sequencing results demonstrated that VCare‑360 enriched the relative abundance of Lactobacillus and cut down vaginal Escherichia-Shigella.

CONCLUSION

Lacticaseibacillus paracasei VCare‑360 can inhibit C. albicans infection, modulate vaginal flora and restore the vaginal mucosal barrier, and serves as a promising probiotic candidate for the treatment of Candida‑induced vaginal candidiasis.