title: Human splanchnic amino-acid metabolism.
abstract: Plasma levels of several amino acids are correlated with metabolic dysregulation in obesity and type 2 diabetes. To increase our understanding of human amino-acid metabolism, we aimed to determine splanchnic interorgan amino-acid handling. Twenty patients planned to undergo a pylorus preserving pancreatico-duodenectomy were included in this study. Blood was sampled from the portal vein, hepatic vein, superior mesenteric vein, inferior mesenteric vein, splenic vein, renal vein, and the radial artery during surgery. The difference between arterial and venous concentrations of 21 amino acids was determined using liquid chromatography as a measure of amino-acid metabolism across a given organ. Whereas glutamine was significantly taken up by the small intestine (121.0 ± 23.8 µmol/L; P < 0.0001), citrulline was released (-36.1 ± 4.6 µmol/L; P < 0.0001). This, however, was not seen for the colon. Interestingly, the liver showed a small, but a significant uptake of citrulline from the circulation (4.8 ± 1.6 µmol/L; P = 0.0138) next to many other amino acids. The kidneys showed a marked release of serine and alanine into the circulation (-58.0 ± 4.4 µmol/L and -61.8 ± 5.2 µmol/L, P < 0.0001), and a smaller, but statistically significant release of tyrosine (-12.0 ± 1.3 µmol/L, P < 0.0001). The spleen only released taurine (-9.6 ± 3.3 µmol/L; P = 0.0078). Simultaneous blood sampling in different veins provides unique qualitative and quantitative information on integrative amino-acid physiology, and reveals that the well-known intestinal glutamine-citrulline pathway appears to be functional in the small intestine but not in the colon.
authors.affiliation: Top Institute Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, The Netherlands.|Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: Evelien P J G
authors.initials: EP
authors.lastname: Neis
authors.affiliation: CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, P.O. Box 5800, 6229 HX, Maastricht, The Netherlands.|GROW School for Oncology and Developmental Biology, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Sabrkhany
authors.affiliation: Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: I
authors.initials: I
authors.lastname: Hundscheid
authors.affiliation: Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Schellekens
authors.affiliation: Top Institute Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, The Netherlands.|Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Lenaerts
authors.affiliation: Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: S W
authors.initials: SW
authors.lastname: Olde Damink
authors.affiliation: Top Institute Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, The Netherlands.|CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, P.O. Box 5800, 6229 HX, Maastricht, The Netherlands.
authors.forename: E E
authors.initials: EE
authors.lastname: Blaak
authors.affiliation: Top Institute Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, The Netherlands.|Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.|Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, 6229 ER, Maastricht, The Netherlands.
authors.forename: C H C
authors.initials: CH
authors.lastname: Dejong
authors.affiliation: Department of General Surgery, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands. s.rensen@maastrichtuniversity.nl.
authors.forename: Sander S
authors.identifier: 0000-0001-6175-7224
authors.initials: SS
authors.lastname: Rensen
mesh_terms: D000368:Aged; D000596:Amino Acids / Q000097:blood*; D003106:Colon / Q000098:blood supply / Q000378:metabolism; D004379:Duodenal Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000601:surgery; D005260:Female; D006503:Hepatic Veins / Q000378:metabolism; D006801:Humans; D007421:Intestine, Small / Q000098:blood supply / Q000378:metabolism; D007668:Kidney / Q000098:blood supply / Q000378:metabolism; D008099:Liver / Q000098:blood supply / Q000378:metabolism; D008297:Male; D008642:Mesenteric Veins / Q000378:metabolism; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000601:surgery; D016577:Pancreaticoduodenectomy / Q000379:methods*; D011169:Portal Vein / Q000378:metabolism; D017534:Radial Artery / Q000378:metabolism; D012082:Renal Veins / Q000378:metabolism; D013152:Splanchnic Circulation / Q000502:physiology*; D013154:Spleen / Q000098:blood supply / Q000378:metabolism; D013162:Splenic Vein / Q000378:metabolism
chemical_list: D000596:Amino Acids
keywords: Amino acids; Gut microbiota; Interorgan metabolism; Obesity; Type 2 diabetes