Fig. 2

Cumulative osteogenic effect of Phenamil and PD98059 treatment in rhBMP-2 stimulated human ASCs cultured on SBG-PLGA composites. mRNA levels of osteoblastic markers in (A) 7-day and (B) 21-day ASC cultures on SBG-PLGA composites. ASCs were cultured in osteogenic medium supplemented with 100 ng/ml rhBMP-2 or 100 ng/ml rhBMP-2, 50 µM PD98059 and 20 µM Phenamil. Results are presented as relative mRNA expression compared to mRNA levels in control cells cultured on PLGA with rhBMP-2 only (marked as black line at 1). (C) mRNA levels of selected osteoblastic markers in 3-day osteogenic ASC cultures treated with different doses of rhBMP-2 (25–250 ng/ml), Phenamil (5–50 µM) or PD98059 (1-125 µM); under fluid shear stress. Results are presented as the expression relative to osteogenic cultures treated only with ascorbic acid, dexamethasone and β-glycerophosphate. (D) Graphical hypothesis of BMP-2, PD98059 and Phenamil cross-talk in intracellular signaling. Average values ± SD are indicated. Two-way ANOVA test, *p < 0.05, **p < 0.001, ***p < 0.0001 relative to the PLGA control group or between marked groups. BMP-2 – bone morphogenetic protein 2, OC – osteocalcin, ON – osteonectin, FOS – AP-1 transcription factor subunit (c-fos), OPG – osteoprotegerin