Urine and dried blood spots from children and pregnant women reveal phytochemicals, amino acids, and carnitine metabolites as cowpea consumption biomarkers

Authors: TIPTON, MADISON - Colorado State University; BAXTER, BRIDGET - Colorado State University; PFLUGER, BRIGITTE - Emory University; SAYRE-CHAVEZ, BROOKE - Colorado State University; MUÑOZ-AMATRIAÍN, MARIA - Colorado State University; BROECKLING, COREY - Colorado State University; SHANI, ISSAH - University Of Ghana; STEINER-ASIEDU, MATILDA - University Of Ghana; MANARY, MARK - Children'S Nutrition Research Center (CNRC); RYAN, ELIZABETH - Colorado State University

Submitted to: Molecular Nutrition and Food Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/23/2023
Publication Date: 1/17/2024
Citation: Tipton, M., Baxter, B.A., Pfluger, B.A., Sayre-Chavez, B., Muñoz-Amatriaín, M., Broeckling, C.D., Shani, I., Steiner-Asiedu, M., Manary, M., Ryan, E.P. 2024. Urine and dried blood spots from children and pregnant women reveal phytochemicals, amino acids, and carnitine metabolites as cowpea consumption biomarkers. Molecular Nutrition and Food Research. 68(4). Article e2300222. https://doi.org/10.1002/mnfr.202300222.
DOI: https://doi.org/10.1002/mnfr.202300222

Interpretive Summary: Legume consumption has been proven to promote health across the lifespan; cowpeas has proven to be useful in combating childhood malnutrition and poor weight gain, Ghana has an estimated malnutrition rate of 35.6% of children. This cowpea feeding study aimed to identify a set of metabolic consumption biomarkers in children and adults by analyzing urine and dried blood spots from children (9-21 months) and pregnant women (>18 years) that were collected before and after increasing amounts of four cowpea varieties were consumed for 15 days. Significant increases in amino acids and several chemicals produced by plants specific to cowpea were identified, the set of key metabolites classified as amino acids, lipids, and phytochemicals for dietary legume and cowpea-specific food exposures of could be used in future studies looking at dietary exposure and have significant global health importance.

Technical Abstract: Legumes consumption has been proven to promote health across the lifespan; cowpeas have demonstrated efficacy in combating childhood malnutrition and growth faltering, with an estimated malnutrition prevalence of 35.6% of children in Ghana. This cowpea feeding study aimed to identify a suite of metabolic consumption biomarkers in children and adults. Urine and dried blood spots (DBS) from 24 children (9-21 months) and 21 pregnant women (>18 years) in Northern Ghana are collected before and after dose-escalated consumption of four cowpea varieties for 15 days. Untargeted metabolomics identified significant increases in amino acids, phytochemicals, and lipids. The carnitine metabolism pathway is represented by 137 urine and 43 DBS metabolites, with significant changes to tiglylcarnitine and acetylcarnitine. Additional noteworthy candidate biomarkers are mansouramycin C, N-acetylalliin, proline betaine, N2, N5-diacetylornithine, S-methylcysteine, S-methylcysteine sulfoxide, and cis-urocanate. S-methylcysteine and S-methylcysteine sulfoxide are targeted and quantified in urine. This feeding study for cowpea biomarkers supports the utility of a suite of key metabolites classified as amino acids, lipids, and phytochemicals for dietary legume and cowpea-specific food exposures of global health importance.