Fig. 3.

AA stimulates osterix expression via modulating prolyl hydroxylase activity. A: effects of desferrioxamine (DFO) and FeCl₂ on AA-induced Osx expression. Primary osteoblasts were treated with DFO (50 μM), FeCl₂ (0.3 μM), or vehicle control in the presence or absence of AA for 24 h. RNA was extracted for real time RT-PCR. The results were expressed as fold changes compared with the expression level of vehicle control without AA treatment (n = 3). B–E: effects of dimethyloxallyl glycineon (DMOG) or protocatechuic acid ethyl ester aka ethyl 3, 4-dihydroxybenzoate (EDHB) on AA-induced Osx, HIF1α, and VEGF expression. MC3T3-E1 osteoblasts were treated with vehicle, DMOG (500 μM), or EDHB (500 μM) for 30 min prior to 24 h treatment with or without AA. RNA and total cellular proteins were extracted for real time RT-PCR and Western blot. The results are expressed as fold change compared with the expression level of vehicle control without AA treatment (n = 3). *Statistical significance compared with expression level of corresponding controls in the absence of AA (P < 0.01).