title: Insulin attenuates the stimulatory effects of tumor necrosis factor alpha on 11beta-hydroxysteroid dehydrogenase 1 in human adipose stromal cells.
abstract: Obesity is frequently associated with insulin-resistance and abnormal glucose homeostasis. Recent evidence indicates that TNFalpha may play a role in mediating the insulin-resistance of obesity through its overexpression in adipose tissue. Previously, we have shown that human adipose stromal cells contain 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) mRNA and activity. The present study was designed to examine the effects of insulin on 11beta-HSD1 expression in human adipose stromal cells under basal and TNFalpha-stimulated conditions. The cells were obtained from breast adipose tissue by collagenase digestion, and grown to confluence under replicating conditions in 10% fetal bovine serum. The cells were transferred to serum-free medium for 24 h prior to treatment with either TNFalpha, insulin or both for a further 24 h. The level of 11beta-HSD1 reductase activity was determined by measuring the conversion of [(3)H]-cortisone to [(3)H]-cortisol at a substrate concentration of 10 nM. Treatment with TNFalpha at concentrations of 0.1-10 ng/ml resulted in a dose dependent increase in 11beta-HSD1 reductase activity from 1.5 to 10-fold. Insulin (0.1-100 nM) had no effect under basal conditions, but inhibited the stimulatory effects of TNFalpha (5 ng/ml) on 11beta-HSD1 reductase activity in a dose dependent fashion (8-66%) inhibition). Northern blot analysis revealed corresponding changes in the level of 11beta-HSD1 mRNA, suggesting that the effects of TNFalpha and insulin on 11beta-HSD1 activity are mediated at the level of gene transcription. The interaction between insulin and TNFalpha suggests that local and systemic factors may act in a concerted fashion to modulate glucocorticoid activity in adipose and other peripheral tissues.
authors.affiliation: Department of Pharmacology, University of Utrecht, 3584CA, Utrecht, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Handoko
authors.forename: K
authors.initials: K
authors.lastname: Yang
authors.forename: B
authors.initials: B
authors.lastname: Strutt
authors.forename: W
authors.initials: W
authors.lastname: Khalil
authors.forename: D
authors.initials: D
authors.lastname: Killinger
mesh_terms: D042842:11-beta-Hydroxysteroid Dehydrogenases; D000273:Adipose Tissue / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D004347:Drug Interactions; D006801:Humans; D006913:Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D007328:Insulin / Q000008:administration & dosage / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D014158:Transcription, Genetic / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D007328:Insulin; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D006913:Hydroxysteroid Dehydrogenases; D042842:11-beta-Hydroxysteroid Dehydrogenases