An NMR Metabolomic Study in the Old Order Amish to Study Increased Dietary Salt Associated with Elevation of Organic Osmolytes Detected in Urine
Guoyun Bai, Nga H. Brereton, Kathy Ryan, Michael Shapiro and Nanette Steinle
Pages 70-75 (6)
Studies have been performed to investigate the metabolic effects of high and low salt diets in Old Order Amish
using a 1H nuclear magnetic resonance (1H NMR)-based metabolomic method. Subjects received a high and low sodium
diet for 6 days each, separated by a 6-14 day washout period. Urine samples were collected on the fourth to sixth days of
each diet and evaluated by NMR. Over 30 metabolites were identified and the whole 1H NMR spectra of 37 samples from
two diet groups were analyzed by principle component analysis (PCA) and Partial Least Squares Discriminant Analysis
(PLS-DA). Osmolytes, such as trimethlamine N-oxide (TMAO), glycine, 1- and 3- methylhistidine, showed distinct differences
between the low and high salt groups which may be associated with renal stress coming from the high salt diet.
From this study, it can be established that the NMR spectrum provides a unique profile for the high salt diet and that metabolomic
technology is of value for the analysis of human dietary data.
Diet, high salt, low salt, metabolomics, NMR, old order Amish.
University of Maryland School of Pharmacy, Baltimore Maryland 21201, USA.