MRI Reveals Human Brown Adipose Tissue Is Rapidly Activated in Response to Cold

Stephan M Oreskovich; Frank J Ong; Basma A Ahmed; Norman B Konyer; Denis P Blondin; Elizabeth Gunn; Nina P Singh; Michael D Noseworthy; Francois Haman; Andre C Carpentier; Zubin Punthakee; Gregory R Steinberg; Katherine M Morrison

doi:10.1210/js.2019-00309

MRI Reveals Human Brown Adipose Tissue Is Rapidly Activated in Response to Cold

J Endocr Soc. 2019 Oct 14;3(12):2374-2384. doi: 10.1210/js.2019-00309. eCollection 2019 Dec 1.

Authors

Stephan M Oreskovich^{1

2}, Frank J Ong¹, Basma A Ahmed^{2

3}, Norman B Konyer⁴, Denis P Blondin⁵, Elizabeth Gunn^{1

2}, Nina P Singh⁶, Michael D Noseworthy^{4

7

8}, Francois Haman⁹, Andre C Carpentier¹⁰, Zubin Punthakee^{1

2

11}, Gregory R Steinberg^{2

3

11}, Katherine M Morrison^{1

2}

Affiliations

¹ Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
² Centre for Metabolism, Obesity and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.
³ Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
⁴ Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada.
⁵ Department of Pharmacology and Physiology, Faculty of Medicine and Health Sciences, Centre de Recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
⁶ Department of Radiology, McMaster University Medical Center, Hamilton, Ontario, Canada.
⁷ Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada.
⁸ McMaster School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada.
⁹ School of Human Kinetics, University of Ottawa, Ottawa, Ontario, Canada.
¹⁰ Division of Endocrinology, Department of Medicine, Centre de Recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada.
¹¹ Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.

Abstract

Context: In rodents, cold exposure induces the activation of brown adipose tissue (BAT) and the induction of intracellular triacylglycerol (TAG) lipolysis. However, in humans, the kinetics of supraclavicular (SCV) BAT activation and the potential importance of TAG stores remain poorly defined.

Objective: To determine the time course of BAT activation and changes in intracellular TAG using MRI assessment of the SCV (i.e., BAT depot) and fat in the posterior neck region (i.e., non-BAT).

Design: Cross-sectional.

Setting: Clinical research center.

Patients or other participants: Twelve healthy male volunteers aged 18 to 29 years [body mass index = 24.7 ± 2.8 kg/m² and body fat percentage = 25.0% ± 7.4% (both, mean ± SD)].

Interventions: Standardized whole-body cold exposure (180 minutes at 18°C) and immediate rewarming (30 minutes at 32°C).

Main outcome measures: Proton density fat fraction (PDFF) and T2* of the SCV and posterior neck fat pads. Acquisitions occurred at 5- to 15-minute intervals during cooling and subsequent warming.

Results: SCV PDFF declined significantly after only 10 minutes of cold exposure [-1.6% (SE: 0.44%; P = 0.007)] and continued to decline until 35 minutes, after which time it remained stable until 180 minutes. A similar time course was also observed for SCV T2*. In the posterior neck fat (non-BAT), there were no cold-induced changes in PDFF or T2*. Rewarming did not result in a change in SCV PDFF or T2*.

Conclusions: The rapid cold-induced decline in SCV PDFF suggests that in humans BAT is activated quickly in response to cold and that TAG is a primary substrate.

Keywords: MRI; PDFF; T2*; brown adipose tissue; cold exposure.

Publication types

Case Reports