In Vivo Confirmation of the Antimicrobial Effect of Probiotic Candidates against Gardnerella vaginalis

Microorganisms. 2021 Aug 9;9(8):1690. doi: 10.3390/microorganisms9081690.

Abstract

Bacterial vaginosis (BV) is caused by a microbial imbalance of the vaginal ecosystem, causing genital discomfort and potentially even various complications in women. Moreover, research on the treatment or prevention of BV is increasing. In this study, we evaluated the antimicrobial and anti-inflammation effects of the lactic acid bacteria (LAB) Ligilactobacillus salivarius MG242, Limosilactobacillus fermentum MG901, and Lactiplantibacillus plantarum MG989 in a BV-induced mice model. The oral administration of the LAB significantly inhibited the growth of Gardnerella vaginalis up to 43% (p < 0.05). The LAB downregulated the expression of pro-inflammatory cytokines (IL-1β and TNF-α) and myeloperoxidase (p < 0.05). Upon histological examination, the exfoliation of epithelial cells in the vaginal tissues was found to be reduced in the probiotic administration group compared to the infected group. In addition, the LAB tolerated the gastric and/or intestinal simulated conditions and proliferated, showing potential in promoting health based on hemolysis activity, antibiotic susceptibility, enzyme activity, and lactic acid production. Altogether, our results showed that the investigated LAB may be a good food ingredient candidate for ameliorating BV in women.

Keywords: Gardnerella vaginalis; bacterial vaginosis; lactic acid; probiotics.