Bisphenol A Diglycidyl Ether Induces Adipogenic Differentiation of Multipotent Stromal Stem Cells through a Peroxisome Proliferator-Activated Receptor Gamma-Independent Mechanism

BACKGROUND: Bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE), used in manufacturing coatings and resins, leach from packaging materials into food. Numerous studies suggested that BPA and BADGE may have adverse effects on human health, including the possibility that exposure to such chemicals can be superimposed on traditional risk factors to initiate or exacerbate the development of obesity. BPA is a suspected obesogen, whereas BADGE, described as a peroxisome proliferator activated receptor gamma (PPAR gamma) antagonist, could reduce weight gain. OBJECTIVES: We sought to test the adipogenic effects of BADGE in a biologically relevant cell culture model. METHODS: We used multipotent mesenchymal stromal stem cells (MSCs) to study the adipogenic capacity of BADGE and BPA and evaluated their effects on adipogenesis, osteogenesis, gene expression, and nuclear receptor activation. DISCUSSION: BADGE induced adipogenesis in human and mouse MSCs, as well as in mouse 3T3-L1 preadipocytes. In contrast, BPA failed to promote adipogenesis in MSCs, but induced adipogenesis in 3T3-L1 cells. BADGE exposure elicited an adipogenic gene expression profile, and its ability, to induce adipogenesis and the expression of adipogenic genes was not blocked by known PPAR gamma antagonists. Neither BADGE nor BPA activated or antagonized retinoid "X" receptor (RXR) or PPAR gamma in transient transfection assays. CONCLUSIONS: BADGE can induce adipogenic differentiation in both MSCs and in preadipocytes at low nanomolar concentrations comparable to those that have been observed in limited human bio-monitoring. BADGE probably acts through a mechanism that is downstream of, or parallel to, PPAR gamma.