Metabolomics of postprandial plasma alterations: a comprehensive Japanese study.

While endogenous metabolites in plasma can be used as clinical biomarkers, intra-day variations should be carefully considered. The postprandial effect is a large contributing factor and is dependent on regional features (e.g. meals, ethnicity). Thus, for clinical application, regional-specific postprandial baseline data are required. In this study, 10 healthy Japanese volunteers of different ages and genders ate the same meal, and blood samples were taken 30 min before and 1 h after the meal challenge. Plasma metabolomics was conducted and metabolites that significantly changed with the meal challenge were extracted. Principal component analysis of the data from 1101 metabolites showed a postprandial shift with a common direction despite marked individual variation. Pathway enrichment analysis demonstrated known postprandial effects, including the energy utilization shift from lipolysis to glycolysis and the elevation of bile acids for lipid absorption. Other postprandial metabolic changes were observed, including decreases in orexigenic signals and increases of food-derived components. The postprandial alteration accumulated in this study will be used for the understanding of Japanese clinical metabolomics for health promotion in Japan.