Title
Bioavailability of tryptophan from a single oral dose of a trytophan-enriched peptide mixture in healthy men
Author
Brink, E.J.
Boelsma, E.
Steijns, J.
Hendriks, H.F.J.
TNO Voeding Centraal Instituut voor Voedingsonderzoek TNO
Publication year
2004
Abstract
The aim of the study was to investigate the bioavailability of tryptophan (Trp) from a Trp-enriched peptide mixture in healthy men. A second objective was to investigate the effect of this Trp-enriched protein hydrolysate on potential parameters of serotonergic activity. serum serotonim melatonin and prolactin and urinary 5-hydroxyindol-acetic acid and 6-sulfatoxymelatonin. Glucose and insulin were measured as the placebo consisted of orange juice with added glucose. The study was a randomised, double blind, placebo-controlled, four-way crossover trial in eight healthy male subjects. Treatments consisted of a single oral load of a Trp-enriched protein hydrolysate containing 500 mg L-Trp, 500 mg L-Trp plus addition of a mixture of amino acids having the same composition as in the hydrolysate, 500 mg L-Trp, and placebo. Before and after ingestion blood and urine were collected during a period of 4 hours. The Trp-enriched protein hydrolysate increased the plasma Trp/LNAA ratio by about 70% at 60 to 90 min after ingestion. AM three Trp treatments induced a comparable plasma Trp-response demonstrating that Trp is readily available for the body independent of whether it was peptide-bonded or in free amino acid form. None of the Trp treatments affected serum serotonim prolactin, melatonin and insulin concentrations, as well as urinary 5-hydroxyindol-acetic acid and 64-sulfatoxymelatonin concentrations during the 4-hour measurement period in the morning. Copyright © 2004 by New Century Health Publishers, LLC.
Subject
Biology Health
Physiological Sciences
Amino acids
Dietary supplements
Serotonergic activity
Tryptophan
5 hydroxyindoleacetic acid
6 hydroxymelatonin o sulfate
Alanine
Arginine
Aspartic acid
Cystine
Glucose
Glutamic acid
Histidine
Insulin
Isoleucine
Leucine
Lysine
Melatonin
Methionine
Phenylalanine
Prolactin
Proline
Protein hydrolysate
Serine
Serotonin
Threonine
Tryptophan
Valine
Adult
Amino acid blood level
Area under the curve
Blood analysis
Brain function
Chemical binding
Clinical trial
Controlled clinical trial
Controlled study
Crossover procedure
Double blind procedure
Drug bioavailability
Human
Human experiment
Insulin blood level
Male
Metabolic parameters
Normal human
Prolactin blood level
Randomized controlled trial
Review
Serotonin blood level
Serotonin brain level
Serotonin metabolism
Urinalysis
Urine level
To reference this document use:
http://resolver.tudelft.nl/uuid:782f9cf5-0a5c-44b0-aad4-d25306c5e068
TNO identifier
237923
ISSN
1540-7535
Source
Current Topics in Nutraceutical Research, 2 (3), 169-176
Document type
article