Bisphenol a induces differentiation of human preadipocytes in the absence of glucocorticoid and is inhibited by an estrogen-receptor antagonist

Abstract

background: Obesity is a major health concern in the developed world, and increasing evidence suggests that exposures to common environmental substances may enhance the risk for the development of this disease. objectiveS: The current study examines the effect of the ubiquitous plastic monomer bisphenol A (BPA) on the differentiation of primary human preadipocytes in vitro and the role of the estrogen and glucocorticoid receptors. mathods: In this study, the mechanism of BPA-induced adipogenesis in preadipocytes from donors with healthy body mass index in the absence of exogenous glucocorticoid was evaluated. The effects of estradiol, the estrogen-receptor (ER) antagonist ICI and the glucocorticoid receptor (GR) antagonist RU486 on BPA-induced adipogenesis were examined. The expression levels of key adipogenic factors were assessed. results: Treatment of preadipocytes with 1-50 mM BPA induced a dose-dependent increase in differentiation and lipid accumulation as determined by lipid staining and triacylglyceride quantification. BPA also induced expression of the adipogenic markers aP2, adipsin, peroxisome proliferator-activated receptor g and the CCAAT-enhancer-binding proteins a and b. Co-treatment of cells with ICI inhibited the BPA-induced increase in aP2 levels, while treatment with ICI or estradiol alone had no effect. Treatment of cells with the GR antagonist RU486 had no effect on BPA-induced differentiation as evaluated by aP2 levels. conclusionS: This study is one of the first to show that BPA induces human adipocyte differentiation in the absence of exogenous glucocorticoid through a non-classical ER pathway rather than through GR activation. These studies add to the growing evidence that endocrine-disrupting chemicals such as BPA have the potential to modulate adipogenesis and impact human biology.© 2014 Macmillan Publishers Limited.