title: Brown adipose tissue function is accompanied by cerebral activation in lean but not in obese humans.
abstract: Brown adipose tissue (BAT) is able to generate heat and dissipate energy in response to cold exposure in mammals. It has recently been acknowledged that adult humans also have functional BAT, whose metabolic activity is reduced in obesity. In healthy humans, the cerebral mechanisms that putatively control BAT function are unclear. By using positron emission tomography (PET), we showed that cold-induced BAT activation is associated with glucose metabolism in the cerebellum, thalamus, and cingulate, temporoparietal, lateral frontal, and occipital cortices in lean participants, whereas no such associations were found under warm control conditions. The cold-induced increase in cerebral glucose metabolism was more robust in lean than obese participants. Cerebral glucose metabolism was not associated with skeletal muscle or white adipose tissue glucose uptake under warm or cold conditions. In conclusion, BAT metabolism was accompanied by the activation of specific cerebral regions, and this shows an uncharacterized role that the brain plays in the regulation of BAT function. In obese participants, the cold-induced response in cerebral activity was attenuated that provides a clue for obesity-induced impairment in BAT metabolism.
authors.affiliation: Turku PET Centre, University of Turku, Turku, Finland.
authors.forename: Janne
authors.initials: J
authors.lastname: Orava
authors.affiliation: 1] Turku PET Centre, University of Turku, Turku, Finland [2] Department of Biomedical Engineering and Computational Science, School of Science, Aalto University, Espoo, Finland [3] Brain Research Unit, O.V. Lounasmaa Laboratory, School of Science, Espoo, Finland.
authors.forename: Lauri
authors.initials: L
authors.lastname: Nummenmaa
authors.affiliation: Department of Nuclear Medicine, Turku University Hospital, Turku, Finland.
authors.forename: Tommi
authors.initials: T
authors.lastname: Noponen
authors.affiliation: Turku PET Centre, University of Turku, Turku, Finland.
authors.forename: Tapio
authors.initials: T
authors.lastname: Viljanen
authors.affiliation: 1] Turku PET Centre, University of Turku, Turku, Finland [2] Department of Radiology, Tampere University Hospital, Tampere, Finland.
authors.forename: Riitta
authors.initials: R
authors.lastname: Parkkola
authors.affiliation: 1] Turku PET Centre, University of Turku, Turku, Finland [2] Department of Endocrinology, Turku University Hospital, Turku, Finland.
authors.forename: Pirjo
authors.initials: P
authors.lastname: Nuutila
authors.affiliation: 1] Turku PET Centre, University of Turku, Turku, Finland [2] Turku PET Centre, Turku University Hospital, Turku, Finland.
authors.forename: Kirsi A
authors.initials: KA
authors.lastname: Virtanen
mesh_terms: D002001:Adipose Tissue, Brown / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D003080:Cold Temperature; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D009765:Obesity / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology; D049268:Positron-Emission Tomography; D011859:Radiography
chemical_list: D005947:Glucose