2,3,7,8-Tetrachlorodibenzo-p-Dioxin and TGF-β3 Mediated-Mouse Embryonic Palatal Mesenchymal Cells.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a well-known environmental teratogenic agent for cleft palate. But transforming growth factor beta 3 (TGF-beta 3) is an essential growth factor for palatogenesis. This study is to clarify effects of TCDD and TGF-beta 3 in mouse embryonic palatal mesenchymal (MEPM) cells. The result showed that with increase of TCDD (0.5 nM-10 nM), the expression of TGF-beta 3 increased, but after 10 nM TCDD, the expression of TGF-beta 3 reduced. The viabilities of MEPM cells decreased in 10 nM TCDD-treated group. But the viabilities increased in 10 ng/mL TGF-beta 3-treated group, or the viabilities were between that of them in combination of 10 nM TCDD and 10 ng/mL TGF-beta 3-treated group. This phenomenon was the same as the motilities. In addition, we found that the expression of phosphorylated Smad2/3 and Smad7 was increased by 10 nM TCDD, 10 ng/mL TGF-beta 3, or combination of 10 nM TCDD and 10 ng/mL TGF-beta 3 induced, but the expression of Smad4 was decreased. These data revealed that the TGF-beta/Smad signaling pathway affected TCDD and TGF-beta 3 in MEPM cells.