Short-term HFD does not alter lipolytic function of adipocytes.
A short bout of high fat diet (HFD) impairs glucose tolerance and hepatic insulin sensitivity. We recently identified adipose tissue inflammation and resulting dysfunctional adipose tissue-liver cross-talk as an early event in the development of HFD-induced hepatic insulin resistance. In particular, reducing white adipose tissue (WAT) inflammation by adipocyte-specific depletion of Fas/CD95 protected mice from developing hepatic insulin resistance but not hepatic steatosis. Herein, we expanded our previous work and determined the impact of four days of HFD on lipolytic activity of isolated adipocytes. Compared with chow-fed mice, the degree of basal and isoproterenol-stimulated free fatty acid (FFA) and glycerol release was similar in HFD-fed animals. Moreover, insulin's ability to suppress lipolysis remained intact, suggesting retained insulin sensitivity. Despite unaltered lipolysis, circulating FFA concentrations were greatly increased in non-fasted HFD-fed mice. In conclusion, a short-term HFD challenge does not affect lipolytic function of adipocytes. The observed increase of circulating FFA levels in randomly fed animals may rather be the result of increased dietary fat supply.
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland ; Zurich Center for Integrative Human Physiology; University of Zurich; Zurich, Switzerland.
Michael Sf
MS
Wiedemann
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland.
Stephan
S
Wueest
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland ; Institute of Human Movement Sciences; ETH Zurich; Zurich, Switzerland.
Alexandra
A
Grob
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland.
Flurin
F
Item
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland.
Eugen J
EJ
Schoenle
Division of Pediatric Endocrinology and Diabetology; University Children's Hospital; Zurich, Switzerland ; Children's Research Center; University Children's Hospital; Zurich, Switzerland ; Zurich Center for Integrative Human Physiology; University of Zurich; Zurich, Switzerland.
Daniel
D
Konrad
adipose tissue–liver crosstalk; diabetes mellitus; fat depot; lipolysis; lipotoxicity