Probiotic lactobacillus and estrogen effects on vaginal epithelial gene expression responses to Candida albicans

Background: vaginal epithelial cells have receptors,signal transduction mechanisms,and cytokine secretion capabilities to recruit host defenses against candida albicans infections. this research evaluates how probiotic lactobacilli affect the defensive epithelial response. methods: this study used quantitative reverse transcription-polymerase chain reaction assay (qrt-pcr),flow cytometry,and a multiplex immunoassay to observe changes in the regulation of gene expression related to cytokine responses in the vk2 (e6/e7) vaginal epithelial cell line treated with 17β-estradiol,exposed to probiotic lactobacillus rhamnosus gr-1® and lactobacillus reuteri rc-14® and challenged with c. albicans. data were statistically evaluated by repeated measures analysis of variance and paired t-tests where appropriate. results: c. albicans induced mrna expression of genes related to inflammatory cytokine responses associated with nuclear factor-kappa b (nf-κb) and mitogen-activated protein kinase (mapk) signal transduction pathways. 17β-estradiol suppressed expression of interleukin-1α (il-1α),il-6,il-8,and tumor necrosis factor alpha (tnfα) mrna. probiotic lactobacilli suppressed c. albicans-induced nuclear factor-kappa b inhibitor kinase kinase alpha (iκκα),toll-like receptor-2 (tlr2),tlr6,il-8,and tnfα,also suggesting inhibition of nf-κb signaling. the lactobacilli induced expression of il-1α,and il-1β mrna,which was not inhibited by curcumin,suggesting that they induce an alternate inflammatory signal transduction pathway to nf-κb,such as the mitogen activated protein kinase and activator protein-1 (mapk/ap-1) signal transduction pathway. curcumin inhibited il-13 secretion,suggesting that expression of this cytokine is mainly regulated by nf-κb signaling in vk2 cells. conclusions: the results suggest that c. albicans infection induces pro-inflammatory responses in vaginal epithelial cells,and estrogen and lactobacilli suppress expression of nf-κb-related inflammatory genes. probiotic lactobacilli may induce il-1α and il-1β expression by an alternate signal transduction pathway,such as mapk/ap-1. activation of alternate signaling mechanisms by lactobacilli to modify epithelial cell cytokine production may be a mechanism for probiotic modulation of morbidity in vulvovaginal candidiasis. © 2012 wagner and johnson.; licensee biomed central ltd.