Metabologenomic approach reveals intestinal environmental features associated with barley-induced glucose tolerance improvements in Japanese cohort: a randomized controlled trial

Abstract

AbstractConsumption of barley has been known to exert beneficial effects on metabolic disorders; however, it has also been reported that there are inter-individual differences in these responses. Recent evidence has suggested that these individual differences are mediated by the gut microbiota. Therefore, in the present study, we aimed to understand the relationship between the intestinal environment, including gut microbiota, and metabolic disorders. A randomized controlled trial in Japanese subjects with 4-week consumption of barley or control food was conducted. In this study, we analyzed the intestinal environment, including microbiota and their metabolites, and blood parameters were assessed collectively. We found that microbial genera Blautia and Agathobacter belonging to Lachnospiraceae, and fecal metabolites such as azelate were increased 1.31-fold, 1.84-fold, and 1.48-fold after barley consumption, respectively. Furthermore, the subjects whose glucose tolerance were slightly impaired showed improvement in their glucose tolerance index following the barley consumption. Additionally, the analysis showed that the increase in the abundance of the Anaerostipes was correlated with the improvement in the glucose tolerance index. Our findings indicate that the effects of barley consumption for glucose tolerance are partly defined by the intestinal environment of consumers, providing a quantitative measurement of the dietary effect based on the intestinal environment.