title: Postprandial fatty acid uptake and adipocyte remodeling in angiotensin type 2 receptor-deficient mice fed a high-fat/high-fructose diet.
abstract: The role of the angiotensin type-2 receptor in adipose physiology remains controversial. The aim of the present study was to demonstrate whether genetic angiotensin type-2 receptor-deficiency prevents or worsens metabolic and adipose tissue morphometric changes observed following a 6-week high-fat/high-fructose diet with injection of a small dose of streptozotocin. We compared tissue uptake of nonesterified fatty acid and dietary fatty acid in wild-type and angiotensin type-2 receptor-deficient mice by using the radiotracer 14(R,S)-[(1) (8)F]-fluoro-6-thia-heptadecanoic acid in mice fed a standard or high-fat diet. Postprandial fatty acid uptake in the heart, liver, skeletal muscle, kidney and adipose tissue was increased in wild-type mice after a high-fat diet and in angiotensin type-2 receptor-deficient mice on both standard and high-fat diets. Compared to the wild-type mice, angiotensin type-2 receptor-deficient mice had a lower body weight, an increase in fasting blood glucose and a decrease in plasma insulin and leptin levels. Mice fed a high-fat diet exhibited increased adipocyte size that was prevented by angiotensin type-2 receptor-deficiency. Angiotensin type-2 receptor-deficiency abolished the early hypertrophic adipocyte remodeling induced by a high-fat diet. The small size of adipocytes in the angiotensin type-2 receptor-deficient mice reflects their inability to store lipids and explains the increase in fatty acid uptake in non-adipose tissues. In conclusion, a genetic deletion of the angiotensin type-2 receptor is associated with metabolic dysfunction of white adipose depots, and indicates that adipocyte remodeling occurs before the onset of insulin resistance in the high-fat fed mouse model.
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Christophe
authors.initials: C
authors.lastname: Noll
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; The Québec Heart and Lung Institute Research Center, Université Laval, Québec, Canada.
authors.forename: Sébastien M
authors.initials: SM
authors.lastname: Labbé
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Sandra
authors.initials: S
authors.lastname: Pinard
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Shum
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Lyne
authors.initials: L
authors.lastname: Bilodeau
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Lucie
authors.initials: L
authors.lastname: Chouinard
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada; Sherbrooke Molecular Imaging Center of CRCHUS and Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada.
authors.forename: Serge
authors.initials: S
authors.lastname: Phoenix
authors.affiliation: The Québec Heart and Lung Institute Research Center, Université Laval , Québec, Canada.
authors.forename: Roger
authors.initials: R
authors.lastname: Lecomte
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: André C
authors.initials: AC
authors.lastname: Carpentier
authors.affiliation: Department of Medicine, Division of Endocrinology, Faculty of Medicine and Health Sciences, Université de Sherbrooke , Sherbrooke, Québec, Canada.
authors.forename: Nicole
authors.initials: N
authors.lastname: Gallo-Payet
keywords: Adipose tissue; NEFA; adipocyte; angiotensin type 2 receptor; high-fat/high-fructose diet; insulin resistance