Impact of cranberry juice consumption on gut and vaginal microbiota in postmenopausal women

Abstract

AbstractCranberries have long been purported to provide protection against urinary tract infections. There is a line of evidence suggesting that causal pathogens might be seeded from the bacteria reservoirs in the intestinal and vaginal tracts. We tested the hypothesis whether cranberry intake would reshape bacteria taxa in the gut, as well as the vaginal ecosystem. A total of 25 postmenopausal women were enrolled into a randomized, double‐blind, placebo‐controlled study. Stool samples and vaginal swabs were collected at baseline and after 15 days of consumption of placebo or cranberry beverages, microbiota analyses were performed by Illumina Miseq sequencing following a double‐index 16S rRNA gene amplicon. All baseline stool samples generally fell in theBacteroidesenterotype. Significant increases ofPrevotella(P = 0.04),ClostridiumXIVa members (P = 0.04),Eggerthella(P = 0.03), andBifidobacterium(P = 0.02) were shown following the cranberry juice intervention; this indicates modulation of the gut microbiota by cranberry components. Baseline vaginal microbiotas fell in three distinct patterns—Lactobacillusdominant, diversified microbiome, andStreptococcusdysbiosis. Compared with the placebo, the cranberry intervention significantly reduced the abundance of pathogenicStreptococcus(P = 0.04) in the dysbiosis group and increased commensal bacteriaAnaerococcus,Finegoldia,Actinomyces, andCorynebacteriumin the diversified microbiome and dysbiosis groups. Overall, these data suggest that cranberry consumption may improve vaginal microbiota composition in individuals with dysbiosis. Gut‐borne taxa stimulation by the combination of cranberry oligosaccharides and polyphenols present in the cranberry product potentially mediates these beneficial properties.