Metabologenomics identified fecal biomarkers for bowel movement regulation by Bifidobacterium longum capsules: an RCT

Background: Bifidobacterium longum supplementation can be used to regulate bowel movement; however, individuals vary in the response to B. longum treatment. One putative factor is the gut microbiota; recent studies have reported that the gut microbiota mediates diet or drug effects. Here, we investigated intestinal features related to B. longum effectiveness in increasing bowel movement frequency. Results: A randomized, double-blind controlled crossover trial was conducted with twenty Japanese subjects selected from 50 participants. The subjects received a two-week dietary intervention consisting of B. longum in acid-resistant seamless capsules or similarly encapsulated starch powder. Bowel movement frequency was recorded daily, and time-series fecal collection was conducted for metabologenomic analyses. There were differences among subjects in B. longum intake-induced bowel movement frequency. The responders were predictable by machine learning based on the metabologenomic features of the fecal samples collected before B. longum intake. Between responders and non-responders, the abundances of nine bacterial genera and of three compounds were significantly different. Conclusions: Thus, the gut microbiome and metabolome composition have a strong impact on B. longum supplementation effectiveness in increasing bowel movement frequency, and gut metabologenomics enables B. longum supplementation effect prediction before intake. These findings have implications for the development of personalized probiotic treatments. Trial registration: UMIN-CTR, UMIN000018924. Registered 07 September 2015, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000021894