title: Dietary glutamine supplementation effects on amino acid metabolism, intestinal nutrient absorption capacity and antioxidant response of gilthead sea bream (Sparus aurata) juveniles.
abstract: A study was undertaken to evaluate dietary glutamine supplementation effects on gilthead sea bream performance, intestinal nutrient absorption capacity, hepatic and intestinal glutamine metabolism and oxidative status. For that purpose gilthead sea bream juveniles (mean weight 13.0g) were fed four isolipidic (18% lipid) and isonitrogenous (43% protein) diets supplemented with 0, 0.5, 1 and 2% glutamine for 6weeks. Fish performance, body composition and intestinal nutrient absorption capacity were not affected by dietary glutamine levels. Hepatic and intestinal glutaminase (GlNase), glutamine synthetase (GSase), alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase activities were also unaffected by dietary glutamine supplementation. In the intestine GlNase activity was higher and GSase/GlNase ratio was two-fold lower than in the liver, suggesting a higher use of glutamine for energy production by the intestine than by the liver. The liver showed higher catalase and glucose-6-phosphate dehydrogenase activities, while the intestine presented higher glutathione peroxidase and glutathione reductase activities and oxidised glutathione content, which seems to reveal a higher glutathione dependency of the intestinal antioxidant response. Total and reduced glutathione contents in liver and intestine and superoxide dismutase activity in the intestine were enhanced by dietary glutamine, though lipid peroxidation values were not affected. Overall, differences between liver and intestine glutamine metabolism and antioxidant response were identified and the potential of dietary glutamine supplementation to gilthead sea bream's antioxidant response was elucidated.
authors.affiliation: Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, Edifício FC4, 4169-007 Porto, Portugal; CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal. Electronic address: coutinho.filipe.f@gmail.com.
authors.forename: F
authors.initials: F
authors.lastname: Coutinho
authors.affiliation: Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, Edifício FC4, 4169-007 Porto, Portugal; CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Castro
authors.affiliation: Departamento de Bioquímica y Biología Molecular I, Facultad de Ciencias de la Universidad de Granada, Campus Universitario Fuentenueva, 18071 Granada, Spain; Centro de Genómica e Investigación Oncológica (GENYO), Parque Tecnológico de Ciencias de la Salud, 18007 Granada, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Rufino-Palomares
authors.affiliation: Departamento de Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, Diagonal 643, 08028 Barcelona, Spain.
authors.forename: B
authors.initials: B
authors.lastname: Ordóñez-Grande
authors.affiliation: Departamento de Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, Diagonal 643, 08028 Barcelona, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Gallardo
authors.affiliation: Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, Edifício FC4, 4169-007 Porto, Portugal; CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: A
authors.initials: A
authors.lastname: Oliva-Teles
authors.affiliation: CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
authors.forename: H
authors.initials: H
authors.lastname: Peres
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001120:Arginine / Q000378:metabolism; D004032:Diet; D019587:Dietary Supplements; D005502:Food; D005947:Glucose / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D007408:Intestinal Absorption / Q000187:drug effects*; D007422:Intestines / Q000187:drug effects / Q000201:enzymology; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D021541:Sea Bream / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D005973:Glutamine; D001120:Arginine; D005978:Glutathione; D005947:Glucose
keywords: Brush border membrane vesicles; Gilthead sea bream; Glutamine; Glutathione; Intestine; Liver; Oxidative stress