Selection of Lactobacillus strains as potential probiotics for vaginitis treatment

Abstract

Jos e de las Lajas Mayabeque, CubaLactobacilli are the dominant bacteria of the vaginal tract of healthy women, and imbalance of the local microbiota can predispose women to acquire infections, such as bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC). Although antimicrobial therapy is generally effective, there is still a high incidence of recurrence and increase of microbial resistance due to the repetitive use of antimicrobials. Thus, it has been suggested that administration of probiotics incorporating selected Lactobacillus strains may be an effective strategy for preventing vaginal infections. Accordingly, the in vitro probiotic potential of 23 lactobacilli isolated from the vaginal ecosystem of healthy women from Cuba was evaluated for use in BV and VVC treatments. Eight strains were selected based on their antagonist potential against Gardnerella vaginalis, Candida albicansor both. In vitro assays revealed that all these strains reduced the pathogen counts in co-incubation, showed excellent adhesive properties (biofilm formation and auto-aggregation), were able to co-aggregate with G. vaginalis and C. albicans, yielded high amounts of hydrogen peroxide and lactic acid and demonstrated high adhesion rates to epithelial HeLa cells. Interference tests within HeLa cells showed that all strains were able to reduce the adherence of pathogens by exclusion or displacement. Lactobacilli were able to inhibit HeLa cell apoptosis caused by pathogens when the cells were incubated with the probiotics prior to challenge. These results suggest that these strains have a promising probiotic potential and can be used for prevention or treatment of BV and VVC.

Comparative genomics of human Lactobacillus crispatus isolates reveals genes for glycosylation and glycogen degradation: Implications for in vivo dominance of the vaginal microbiota

“…Biofilm formation was assessed using the crystal violet assay as described by Santos et al . [51] and auto-aggregation as described by Younes et al [52]. Antimicrobial activity against Neisseria gonorrhoeae was assessed by challenging N. gonorrhoeae (WHO-L strain) with varying (neutralized with NaOH to pH 7.0) dilutions of L. crispatus supernatants.…”

The Role of the Cervicovaginal Microbiome on the Genesis and as a Biomarker of Premalignant Cervical Intraepithelial Neoplasia and Invasive Cervical Cancer

“…strains have been isolated from healthy women and their potential as probiotics has been investigated. L. plantarum and L. fermentum strains isolated from healthy Cuban women exhibited antagonic activity against G. vaginalis, C. albicans, as well as remarkable adhesive capacities and lactic acid production [134]. Similarly, L. fermentum 9LB6, 4LB16, and 10LB1 and L. plantarum 9LB4 strains were isolated from Algerian women and suggested as probiotic candidates based on their relevant inhibitory activity of pathogens, lack of hemolytic capability and other beneficial properties according to in vitro studies [135].…”

Lactobacillus rhamnosusinhibitsCandida albicansvirulence factorsin vitroand modulates immune system inGalleria mellonella

“…The inhibition of these virulence factors in C. albicans is an important tool for the treatment of candidiasis. Several studies in the literature showed that some Lactobacillus strains were able to inhibit C. albicans through the production of bacteriocins, environmental alterations through the production and secretion of molecules arising from the metabolism of lactic acid and hydrogen peroxide, or even by mechanical inhibition of adhesion receptors (Orsi et al 2014;Leão et al 2015;Santos et al 2016;Wannun et al 2016). Probiotic bacteria are also capable of modulating the immune systems of their hosts through the production of cytokines and the stimulation of cellular activity (Mendonc ßa et al 2012;Shibasaki et al 2014;Roy et al 2015).…”