Adipogenic and lipolytic effects of chronic glucocorticoid exposure.

Published

Journal Article

Glucocorticoids have been proposed to be both adipogenic and lipolytic in action within adipose tissue, although it is unknown whether these actions can occur simultaneously. Here we investigate both the in vitro and in vivo effects of corticosterone (Cort) on adipose tissue metabolism. Cort increased 3T3-L1 preadipocyte differentiation in a concentration-dependent manner, but did not increase lipogenesis in adipocytes. Cort increased lipolysis within adipocytes in a concentration-dependent manner (maximum effect at 1-10 μM). Surprisingly, removal of Cort further increased lipolytic rates (∼320% above control, P < 0.05), indicating a residual effect on basal lipolysis. mRNA and protein expression of adipose triglyceride lipase and phosphorylated status of hormone sensitive lipase (Ser563/Ser660) were increased with 48 h of Cort treatment. To test these responses in vivo, Sprague-Dawley rats were subcutaneously implanted with wax pellets with/without Cort (300 mg). After 10 days, adipose depots were removed and cultured ex vivo. Both free fatty acids and glycerol concentrations were elevated in fed and fasting conditions in Cort-treated rats. Despite increased lipolysis, Cort rats had more visceral adiposity than sham rats (10.2 vs. 6.9 g/kg body wt, P < 0.05). Visceral adipocytes from Cort rats were smaller and more numerous than those in sham rats, suggesting that adipogenesis occurred through preadipocyte differentiation rather than adipocyte hypertrophy. Visceral, but not subcutaneous, adipocyte cultures from Cort-treated rats displayed a 1.5-fold increase in basal lipolytic rates compared with sham rats (P < 0.05). Taken together, our findings demonstrate that chronic glucocorticoid exposure stimulates both lipolysis and adipogenesis in visceral adipose tissue but favors adipogenesis primarily through preadipocyte differentiation.

Full Text

Duke Authors

Cited Authors

  • Campbell, JE; Peckett, AJ; D'souza, AM; Hawke, TJ; Riddell, MC

Published Date

  • January 2011

Published In

Volume / Issue

  • 300 / 1

Start / End Page

  • C198 - C209

PubMed ID

  • 20943959

Pubmed Central ID

  • 20943959

Electronic International Standard Serial Number (EISSN)

  • 1522-1563

Digital Object Identifier (DOI)

  • 10.1152/ajpcell.00045.2010

Language

  • eng

Conference Location

  • United States