Dexamethasone reduces energy expenditure and increases susceptibility to diet‐induced obesity in mice

Abstract

Objective To investigate how long‐term treatment with dexamethasone affects energy expenditure and adiposity in mice and whether this is influenced by feeding on a high‐fat diet (HFD). Design and Methods Mice were placed on a HFD for 2 weeks and started on dexamethasone at 5 mg/kg every other day during the next 7 weeks. Results Treatment with dexamethasone increased body fat, an effect that was more pronounced in the animals kept on HFD; dexamethasone treatment also worsened liver steatosis caused by the HFD. At the same time, treatment with dexamethasone lowered the respiratory quotient in chow‐fed animals and slowed nightly metabolic rate in the animals kept on HFD. In addition, the acute VO2 acceleration in response to β3 adrenergic‐stimulation was significantly limited in the dexamethasone‐treated animals, as a result of marked decrease in UCP‐1 mRNA observed in the brown adipose tissue of these animals. Conclusions Long‐term treatment with dexamethasone in a mouse model of diet‐induced obesity decreases brown adipose tissue thermogenesis and exaggerates adiposity and liver steatosis. © 2013 American Institute of Chemical Engineers AIChE J, 2013