title: A standardized infrared imaging technique that specifically detects UCP1-mediated thermogenesis in vivo.
abstract: The activation and expansion of brown adipose tissue (BAT) has emerged as a promising strategy to counter obesity and the metabolic syndrome by increasing energy expenditure. The subsequent testing and validation of novel agents that augment BAT necessitates accurate pre-clinical measurements in rodents regarding the capacity for BAT-derived thermogenesis. We present a novel method to measure BAT thermogenesis using infrared imaging following β3-adrenoreceptor stimulation in mice. We show that the increased body surface temperature observed using this method is due solely to uncoupling protein-1 (UCP1)-mediated thermogenesis and that this technique is able to discern differences in BAT activity in mice acclimated to 23 °C or thermoneutrality (30 °C). These findings represent the first standardized method utilizing infrared imaging to specifically detect UCP1 activity in vivo.
authors.affiliation: Department of Pediatrics, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada ; Department of Medicine, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada ; Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Justin D
authors.initials: JD
authors.lastname: Crane
authors.affiliation: Department of Medicine, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada ; Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Emilio P
authors.initials: EP
authors.lastname: Mottillo
authors.affiliation: Department of Nuclear Medicine, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada ; Department of Radiology, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Troy H
authors.initials: TH
authors.lastname: Farncombe
authors.affiliation: Department of Pediatrics, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Morrison
authors.affiliation: Department of Medicine, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada ; Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S 4L8, Canada.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Steinberg
keywords: BAT; Beige fat; Brite fat; Brown adipose tissue; Brown fat; CT, computed tomography; Diabetes; FDG-PET, fluorodeoxyglucose positron emission tomography; MRS, magnetic resonance spectroscopy; Metabolism; Obesity; Thermography; Uncoupling protein-1; fMRI, functional magnetic resonance imaging