Dissociation between brown adipose tissue 18F-FDG uptake and thermogenesis in uncoupling protein deficient mice


Dissociation between brown adipose tissue 18F-FDG uptake and thermogenesis in uncoupling protein deficient mice

Hankir, M. K.; Kranz, M.; Keipert, S.; Andreasen, S.; Kern, M.; Patt, M.; Klöting, N.; Hesse, S.; Brust, P.; Jastroch, M.; Fenske, W. K.

Abstract
18F-FDG PET imaging is routinely used to assess recruitment of BAT thermogenesis which requires mitochondrial uncoupling protein 1 (UCP1). It remains unsettled whether 18F-FDG uptake by BAT is altered in the absence of UCP1-mediated heat production.
METHODS: UCP1 knockout (UCP1 KO) and wild-type (WT) mice received single intraperitoneal injections of the selective β3 adrenergic receptor agonist CL 316, 243 (1mg/kg) and underwent metabolic cage, infrared thermal imaging and static 18F-FDG PET/MRI experiments. Bioenergetics of isolated brown adipocytes were examined by extracellular flux analysis.
RESULTS: In response to CL 316, 243 treatment, oxygen consumption and BAT thermogenesis were diminished in UCP1 KO mice; however the stimulation of 18F-FDG uptake by BAT was fully retained. Brown adipocytes derived from UCP1 KO mice exhibited defective induction of uncoupled respiration when glycolytic flux appeared normal.
CONCLUSION: Increased glucose metabolism in BAT can occur independently of UCP1-mediated thermogenesis.

Keywords: PET; thermogenesis

Permalink: https://www.hzdr.de/publications/Publ-24378
Publ.-Id: 24378