title: The effect of endurance exercise on intestinal integrity in well-trained healthy men.
abstract: Exercise is one of the external factors associated with impairment of intestinal integrity, possibly leading to increased permeability and altered absorption. Here, we aimed to examine to what extent endurance exercise in the glycogen-depleted state can affect intestinal permeability toward small molecules and protein-derived peptides in relation to markers of intestinal function. Eleven well-trained male volunteers (27 ± 4 years) ingested 40 g of casein protein and a lactulose/rhamnose (L/R) solution after an overnight fast in resting conditions (control) and after completing a dual - glycogen depletion and endurance - exercise protocol (first protocol execution). The entire procedure was repeated 1 week later (second protocol execution). Intestinal permeability was measured as L/R ratio in 5 h urine and 1 h plasma. Five-hour urine excretion of betacasomorphin-7 (BCM7), postprandial plasma amino acid levels, plasma fatty acid binding protein 2 (FABP-2), serum pre-haptoglobin 2 (preHP2), plasma glucagon-like peptide 2 (GLP2), serum calprotectin, and dipeptidylpeptidase-4 (DPP4) activity were studied as markers for excretion, intestinal functioning and recovery, inflammation, and BCM7 breakdown activity, respectively. BCM7 levels in urine were increased following the dual exercise protocol, in the first as well as the second protocol execution, whereas 1 h-plasma L/R ratio was increased only following the first exercise protocol execution. FABP2, preHP2, and GLP2 were not changed after exercise, whereas calprotectin increased. Plasma citrulline levels following casein ingestion (iAUC) did not increase after exercise, as opposed to resting conditions. Endurance exercise in the glycogen depleted state resulted in a clear increase of BCM7 accumulation in urine, independent of DPP4 activity and intestinal permeability. Therefore, strenuous exercise could have an effect on the amount of food-derived bioactive peptides crossing the epithelial barrier. The health consequence of increased passage needs more in depth studies.
authors: Wageningen Food and Biobased Research, Wageningen University and Research, Wageningen, The Netherlands lonneke.janssen@wur.nl.|Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands.|Division of Human Nutrition, Wageningen University and Research, Wageningen, The Netherlands.
authors: Lonneke M
authors: 0000-0002-9516-6681
authors: LM
authors: JanssenDuijghuijsen
authors: Division of Human Nutrition, Wageningen University and Research, Wageningen, The Netherlands.
authors: Marco
authors: M
authors: Mensink
authors: Department of Surgery, NUTRIM School of Nutrition and Translational Research in Metabolism Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Kaatje
authors: K
authors: Lenaerts
authors: Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Olsztyn, Poland.
authors: Ewa
authors: E
authors: Fiedorowicz
authors: Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands.
authors: Dorien A M
authors: DA
authors: van Dartel
authors: Wageningen Food and Biobased Research, Wageningen University and Research, Wageningen, The Netherlands.
authors: Jurriaan J
authors: JJ
authors: Mes
authors: Nutricia Research, Utrecht, The Netherlands.
authors: Yvette C
authors: YC
authors: Luiking
authors: Human and Animal Physiology, Wageningen University and Research, Wageningen, The Netherlands.
authors: Jaap
authors: J
authors: Keijer
authors: Wageningen Food and Biobased Research, Wageningen University and Research, Wageningen, The Netherlands.
authors: Harry J
authors: HJ
authors: Wichers
authors: Division of Human Nutrition, Wageningen University and Research, Wageningen, The Netherlands.
authors: Renger F
authors: RF
authors: Witkamp
authors: Division of Human Nutrition, Wageningen University and Research, Wageningen, The Netherlands.|Nutricia Research, Utrecht, The Netherlands.
authors: Klaske
authors: K
authors: van Norren
mesh_terms: D000328:Adult; D064368:Healthy Volunteers; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology*; D007421:Intestine, Small / Q000502:physiology*; D010539:Permeability; D010807:Physical Endurance / Q000502:physiology*; D055815:Young Adult
keywords: Amino acids; betacasomorphin‐7; citrulline; dipeptidylpeptidase‐4; exercise; intestinal permeability