AUTHOR=Chenoll Empar , Moreno Inmaculada , Sánchez María , Garcia-Grau Iolanda , Silva Ángela , González-Monfort Marta , Genovés Salvador , Vilella Felipe , Seco-Durban Cristina , Simón Carlos , Ramón Daniel 

TITLE=Selection of New Probiotics for Endometrial Health

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=9

YEAR=2019

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2019.00114

DOI=10.3389/fcimb.2019.00114

ISSN=2235-2988

ABSTRACT=<p>Microbiota is a crucial player in gynecologic health, in which bacteria can shift to a dysbiotic state triggering a pathogenic process. Based on an ecological understanding of the problem, the aim of this study is to select a potential probiotic strain to improve female reproductive tract based on its capacity to initially lower pH and to promote the reduction of pathogenic bacteria. Based on this rationale, strain <italic>Lactobacillus rhamnosus</italic> BPL005 was initially selected for its capacity to reduce <italic>in vitro</italic> pH levels and produce organic acids. Subsequently, strain <italic>L. rhamnosus</italic> BPL005 (CECT 8800) was demonstrated to have a protective role on endometrial infections in an <italic>in vitro</italic> model of bacterial colonization of primary endometrial epithelial cells with <italic>Atopobium vaginae, Gardnerella vaginalis, Propionibacterium acnes</italic>, and <italic>Streptococcus agalactiae</italic>. In this model, BPL005 when co-cultured with those pathogens was shown to lower pH and to produce organic acids, being lactic acid the most relevant. The co-cultivation of strain <italic>L. rhamnosus</italic> BPL005 with tested reference pathogens produced a significant reduction in <italic>P. acnes</italic> and <italic>St. agalactiae</italic> levels and a non-significant reduction in <italic>A. vaginae</italic> and <italic>G. vaginalis</italic>. The colonization of <italic>L. rhamnosus</italic> BPL005 in the culture decreased IL-6, IL-8, and MCP-1, heightened in the presence of pathogens, and increased IL-1RA and IL-1 beta. Finally, safety was evaluated showing no signs of cytotoxicity, irritation in vaginal tests, or allergic contact dermatitis potential through the Local Lymph Node Assay. Overall, these results show the potential of <italic>L. rhamnosus</italic> BPL005 strain as a probiotic in gynecological health.</p>