Biochemical characterization of rat intestine development using high-resolution magic-angle-spinning ¹H NMR spectroscopy and multivariate data analysis

We report details of metabolic profiles for small intestinal samples obtained using high-resolution magic-angle-spinning (HRMAS) ¹H NMR spectroscopy. Intact samples of jejunum and ileum from male Long Evens rats were analyzed on a 600 MHz spectrometer using standard one and two-dimensional ¹H NMR spectroscopic pulse sequences. The metabolic profiles of ileum and jejunum predominately comprised a number of amino acids, lipids, glycerophosphocholine (GPC), choline, creatine, and ethanol, a number of carboxylic acids including acetate and lactate, and nucleoside bases including cytosine, isocytosine, and uracil. Principal component analysis (PCA) was applied to these NMR data to characterize the biochemical differences between jejunum and ileum tissues. Compared with ileum, jejunum contained higher levels of lipids, GPC, choline, lactate and creatinine, but lower levels of amino acids and acetate. In addition, the age dependence of the biochemical composition of intestinal tissues from young rats (15, 36 days and 3-4 months old) was studied. In general, levels of lipids, lactate, taurine and creatinine were positively correlated with age while amino acids and GPC decreased in the older age group. This study will provide a metabolic reference for further studies assessing the metabolic consequences of nutrition, stress and gut microbiota on intestinal composition.