367-OR: E-cigarette Vaping Exposure Increases Adipose 11ß-HSD1 Expression and Disturbs Glucose Homeostasis in Mice

Abstract

Electronic cigarette (E-cigs) use may increase the prediabetic risk, but the underlying mechanisms remain underexplored. Pre-receptor activation of glucocorticoids (GCs) via 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in adipose tissues has been identified as an important mediator of insulin resistance and type 2 diabetes. However, little is known about the effects of E-cig vaping on 11β-HSD1 and glucose homeostasis. To address this issue, we conducted animal model studies with mice exposed to aerosolized PBS, nicotine-free or nicotine-containing E-cigs, with concurrent exposure to either vehicle or the GC receptor (GR) antagonist RU486. We observed that exposure of E-cig vaping nicotine for 4 weeks increased 11β-HSD1 expression and induced lipase HSL and ATGL abundance within the adipose tissues with induction of hypercortisolemia in response to elevated plasma nicotine levels in mice compared with those of aerosolized E-cig vaping vehicle or PBS controls. Induction of adipose 11β-HSD1 was correlated with elevated the expression of hepatic gluconeogenic enzymes PEPCK and G6Pase and corresponded to the elevated fasting glucose levels. Moreover, E-cig vaping nicotine also increased glucose intolerance, but decreased the glucose-lowing effects of insulin and elevated plasma FFA levels in mice compared with PBS controls. However, E-cig vapor without nicotine did not affect these metabolic parameters. Furthermore, RU486 treatment attenuated E-cig vaping nicotine-induced adipose 11β-HSD1 and lipase expression. In addition, RU486 also attenuated the E-cig-mediated activation of hepatic PEPCK and G6Pase and decreased plasma FFA levels, but did not change the elevated plasma corticosterone levels in mice on E-cig vaping nicotine. These data indicate that E-cig vapor exposure harmfully affects glucose homeostasis and these effects may arise, in part, from aerosol nicotine-induced adipose 11β-HSD1 and GR expression. Disclosure J.Wang: None. T.Friedman: None. M.Jiang: None. Y.Liu: None. J.Liu: None. Y.Wang: None. S.C.J.Kim: None. E.Espinal: None. R.Yang: None. H.Zhong: None. X.M.Shao: None. K.Lutfy: None. Funding Tobacco-Related Disease Research Program (T31IR1603)