Fig. 4.

Involvement of PPARγ in TBBPA-induced lipogenesis.

hMSCs differentiated into osteoblast with 10 μM TBBPA in the absence (-) or presence (+) of 1 μM GW9662 for 21 days. (A) Lipid droplets were stained with oil red O. Morphological changes were observed under a microscope at 40× magnification. (B) Quantitative measurement of lipid droplets stained with oil red O. Oil red O in lipid droplets was eluted with isopropanol. The relative absorbance at 550 nm was expressed as the fold induction as compared with the vehicle. aP2 (C), LPL (D), and PPARγ (E) mRNA levels were measured by quantitative real-time PCR. The relative mRNA level was expressed as the fold induction as compared with the vehicle. The data are presented as means ± SD (n = 5). *P < 0.05, **P < 0.01, significantly different from that in the absence of GW9662.