Lactobacillus pentosus KCA1 Decreases Vaginal and Gut Microbiota Associated with Bacterial Vaginosis

Abstract

Introduction: Bacterial vaginosis (BV) which affects 14%–50% of reproductive-aged women in Nigeria is misdiagnosed and underreported. Treatment option is antibiotics, which leads to recurrent infections. The objectives of this study are three folds: first, to determine effects of oral feeding of Lactobacillus pentosus KCA1 on the vaginal and gut microbiota of women diagnosed with BV; second, to measure the level of two pro-inflammatory cytokines interleukin-1 (IL-1)-beta and IL-6 before and after KCA1 consumption; and third, to determine the relative abundance of bacterial metabolic genes. Materials and Methods: Seven women diagnosed with BV by Nugent score (7–10) were recruited to provide vaginal and gut sample before and after 14-day oral intake of 3 g of L. pentosus KCA1. The DNA from the swabs was processed for 16S rRNA metagenomics using Illumina MiSeq platform. The paired-end sequence FASTQ reads were imported into Illumina Basespace pipeline for quality check. In addition, EzBioCloud pipeline was used for alpha- and beta-diversity estimation using PKSSU4.0 version and open reference UCLUST_MC2 for operational taxonomic units picking at 97% cutoff. Blood samples were analyzed using ELISA technique. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was used to predict the metabolic functions from the 16S rRNA gene dataset. Results: On average, there was no significant difference at P = 0.05 in the alpha-indices typified by Shannon index. The beta-diversity showed different clustering positions with principal coordinate analysis. However, at individual taxonomic categories, there was a significant decrease in the relative abundance of some genera associated with BV after KCA1 feeding with a corresponding increase of Lactobacillus genus. Bacterial genes related to defense systems were upregulated in the vagina. There was a two-fold downregulation of IL-1-beta after consumption of KCA1. Conclusion: Our findings suggest that L. pentosus KCA1 taken orally lowers pro-inflammatory cytokine and IL-1-beta and decreases the relative abundance of BV-associated bacteria.