Oral Presentation Australian & New Zealand Obesity Society 2016 Annual Scientific Meeting

Effect of Glucocorticoid on Brown Adipose Tissue Function in Humans – A Randomised Double-blind Placebo Controlled Cross-over Study (#26)

Moe Thuzar 1 2 3 , W Phillip Law 2 4 , Jeyakantha Ratnasingam 1 , Christina Jang 1 2 , Ken KY Ho 1 2
  1. Department of Endocrinology & Diabetes, Princess Alexandra Hospital, Brisbane, Queensland, Australia
  2. School of Medicine, University of Queensland, Brisbane, Queensland, Australia
  3. Princess Alexandra Hospital, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia
  4. Department of Molecular Imaging, Princess Alexandra Hospital, Brisbane, Queensland, Australia

Background: Glucocorticoid (GC) excess causes obesity. In animals, GC inhibits brown adipose tissue (BAT) function, leading to weight gain. The involvement of BAT in the development of obesity induced by GCs in humans is not known.


Aim: To investigate the effect of GC on BAT function in humans.


Method: In a randomised double-blind cross-over design, 13 healthy adults (6 men, 7 women; age mean±SEM, 28±2 year; BMI 24±1 kg/m2) underwent 1 week each of oral prednisolone (15mg/day) and placebo treatment with an intervening 2-week wash-out period. At the end of each treatment, under standardised cooling (190C), BAT function was assessed by measuring (i) BAT activity on PET-CT scan after 75MBq of FDG (ii) supraclavicular (SCL) skin temperatures using infrared thermography (iii) energy production after a standardised meal using indirect calorimetry.


Results: Compared to placebo, SCL BAT activity (SUVmax 6.1±2.2 vs 3.7±1.2, P=0.049) was lower with prednisolone. During cooling, SCL skin temperature fell to a greater degree with prednisolone (-0.45±0.1 vs -1.0±0.10C, P=0.01). Energy production was stimulated by the meal and the stimulation was significantly higher during prednisolone treatment (187±16 vs 255±25 kcal/day, P<0.01). Postprandially, SCL skin temperature rose during placebo but fell during prednisolone treatment (+0.2±0.1 vs -0.3±0.10C, P=0.03).


Summary: Prednisolone suppresses BAT activity on PET-CT, enhances meal induced energy production but reduces thermogenesis.


Conclusions: GC suppresses the function of human BAT. The enhancement of energy production in the face of a reduced thermogenic response suggests that GC reduces the dissipation of energy as heat, enhancing deposition as energy stores after nutrient intake. This is a likely mechanism by which GC induces obesity.


Acknowledgement: M Thuzar is supported by the Princess Alexandra Hospital Research Support Scheme