title: In vivo measurement of energy substrate contribution to cold-induced brown adipose tissue thermogenesis.
abstract: The present study was designed to investigate the effects of cold on brown adipose tissue (BAT) energy substrate utilization in vivo using the positron emission tomography tracers [(18)F]fluorodeoxyglucose (glucose uptake), 14(R,S)-[(18)F]fluoro-6-thia-heptadecanoic acid [nonesterified fatty acid (NEFA) uptake], and [(11)C]acetate (oxidative activity). The measurements were performed in rats adapted to 27°C, which were acutely subjected to cold (10°C) for 2 and 6 hours, and in rats chronically adapted to 10°C for 21 days, which were returned to 27°C for 2 and 6 hours. Cold exposure (acutely and chronically) led to increases in BAT oxidative activity, which was accompanied by concomitant increases in glucose and NEFA uptake. The increases were particularly high in cold-adapted rats and largely readily reduced by the return to a warm environment. The cold-induced increase in oxidative activity was meaningfully blunted by nicotinic acid, a lipolysis inhibitor, which emphasizes in vivo the key role of intracellular lipid in BAT thermogenesis. The changes in BAT oxidative activity and glucose and NEFA uptakes were paralleled by inductions of genes involved in not only oxidative metabolism but also in energy substrate replenishment (triglyceride and glycogen synthesis). The capacity of BAT for energy substrate replenishment is remarkable.
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: Sébastien M
authors: SM
authors: Labbé
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: Alexandre
authors: A
authors: Caron
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: Inan
authors: I
authors: Bakan
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: Mathieu
authors: M
authors: Laplante
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: André C
authors: AC
authors: Carpentier
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada.
authors: Roger
authors: R
authors: Lecomte
authors: *Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada; Department of Medicine, Centre de Recherche du Centre Hospitalier, and Departments of Nuclear Medicine and Radiobiology, Centre d'Imagerie Moléculaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Canada denis.richard@criucpq.ulaval.ca.
authors: Denis
authors: D
authors: Richard
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism*; D015153:Blotting, Western; D001833:Body Temperature Regulation / Q000502:physiology*; D002478:Cells, Cultured; D003080:Cold Temperature; D004734:Energy Metabolism / Q000502:physiology*; D019788:Fluorodeoxyglucose F18; D008297:Male; D049268:Positron-Emission Tomography; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D022722:Thermogenesis / Q000502:physiology*
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D012333:RNA, Messenger; D019788:Fluorodeoxyglucose F18
keywords: NEFA uptake; glucose uptake; glycogenesis; lipogenesis; positron emission tomography