Effect of synthetic osteogenic growth peptide on proliferation and differentiation of OPG~(-/-)BMSCs in different serum concentration

Objective To investigate the effect of synthetic osteogenic growth peptide(sOGP) on proliferation and differentiation of the cultured bone marrow mesenchymal stem cells(BMSCs) of OPG(osteoprotegerin) gene knockout mouse. Methods Cultured adherent BMSCs(from OPG-/-mouse femoral bone) were used in the study.BMSCs were divided into OGP,CON(control) and BMP-2(bone morphogenetic protein-2) groups.Morphological changes were observed under inverted phase contrast microscope,proliferation curves were obtained by MTT method,and the expression of alkaline phosphatase was detected by PNPP method. Results OGP promoted the proliferation of BMSCs,which increased more significantly in the OGP group than in the other two groups(P0.05,MTT curves) when cells were cultured in LG-DMEM with 10% FBS(fetal bovine serum) medium supplemented with 1×10-8 mol/L dexamethasone,1×10-2 mol/L β-glycerophosphate and 50 μg/mL ascorbic acid on the 3rd and 5th days.The effect of OGP on ALP expression was similar to the CON group,but inferior to the BMP-2 group.ALP expression of BMSCs in BMP-2 group increased significantly in the other two groups(P0.05) on the 3rd and 5th days in different serum concentrations. Conclusions High serum concentration of sOGP promotes the proliferation of OPG-/-BMSCs,however,its effect on ALP expression was inferior to BMP-2.