ANALYSIS OF THE URINARY GLUCOSE-[N, N]-UREIDE CONTENT IN THE STUDY OF THE LACTOSE-[N, N]-UREIDE METABOLISM IN HEALTHY HUMANS
Résumé
Background/Objectives: Lactose-[N, N]-ureide is used to study the fate of the colonic urea-nitrogen metabolism. During the passage through the gastrointestinal tract, lactose ureide is hydrolysed to glucose ureide, which is absorbed to a limited extent from the small intestine and is excreted urinarily. In the present study, a procedure has been developed to quantify the urinary excretion of glucose-[N, N]-ureide. In addition, urine and faecal samples obtained during a dietary intervention study with the prebiotic lactulose were retrospectively analysed. Subjects/Methods: The glucose ureide and lactose ureide content was measured by GC-MS in nineteen healthy volunteers. After consumption of a standard test meal containing 75 mg lactose-[N, N]-ureide, 6 healthy volunteers performed a fractionated 24h urine collection to investigate the urinary excretion of glucose-[N, N]-ureide. In 13 volunteers, the effect of lactulose administration on the urinary excretion of glucose-[N, N]-ureide was analysed. Results: The urinary excretion of glucose-[N, N]-ureide reached its maximum level in the 3-6h urine collection and decreased in the 6-9h urine. The label was still detectable in the 9-24h urine collection. The cumulative excretion of N-labelled glucose ureide after 24h amounted 12.91 %. No significant differences in glucose-[N, N]-ureide excretion were found in either of the urine fractions after administration of lactulose compared to baseline. In none of the urine samples lactose-[N, N]-ureide was detected. Conclusions: In conclusion, the results obtained in the present study indicated that the percentage dose glucose-[N, N]-ureide recovered in urine is rather constant and not influenced by the presence of lactulose.
Origine : Fichiers produits par l'(les) auteur(s)
Loading...