Developing Biomarkers of Rice Bran and Navy Bean Intake via Integrated Metabolomics from Infants, Children and Adults for Association with Gut Health Properties
Current Developments in Nutrition
Objectives Self-reporting methods for dietary exposure are error-prone and have had limited impact to identify food components that mitigate disease risk. The purpose of this study was to use non-targeted and targeted metabolomics from feeding trials with rice bran and navy beans for the identification of dietary biomarkers across the lifespan. Methods Prepared meals/snacks, and biological samples from randomized-controlled trials performed in 50 infants, 38 children and 49 adults were utilized
... dults were utilized in this study. Diet groups were placebo control, rice bran, cooked navy bean powder, or a combination of rice bran/navy beans with increasing daily doses by age group and for duration of 4, 12 or 24 weeks per protocol. Plasma/dried blood spots, urine or stool samples were collected at a baseline, midpoint and endpoint. Non-targeted profiling was performed with UPLC-MS/MS, and metabolite quantification by LC-triple-quadropole (LC-QQQ-MS). A linear mixed model to compare between time points in each group was performed using SAS. Results The plasma/blood metabolomes contained between 771–1001 metabolites and showed variation in ∼20–30% of the profile following intervention. Fold changes over time and fold-differences in metabolite abundance were assessed by age (P < 0.05). There were 10–20 candidate identified from metabolomics across studies and with relevance to rice bran and/or navy bean were applied for targeted assay development. Food metabolomes confirmed metabolite origins and the host and microbial metabolism. Candidate metabolites included pipecolate, S-methlycysteine, S-methylcysteine sulfoxide, trigonelline, N-methyl-pipecolate, pyridoxal, 2-hydroxyhippurate, apigenin, xanthurenate, chiro-inositol, and salicylate. Inter-individual variation was reported across studies, ages and dietary patterns. Conclusions Dietary biomarkers for rice bran and/or navy bean intake merit additional selection criteria from non-targeted metabolomics. Targeted assays will need validation in larger cohort investigations using cross-over study designs and diverse dietary patterns. Funding Sources This work was supported by a grant from the National Institute of Foods and Agriculture-U.S Department of Agriculture (NIFA-USDA).