Effect of calcium sulfate on BMP-2 and VEGF mRNA expression in differentiation from hBMSC to osteoblasts

Objective To study the effect of calcium sulfate(CS) on osteogenic gene expression in differentiation process from human bone marrow stromal cells(hBMSC) to osteoblastic cells,and illuminate its possible biological mechanism of promoting bone formation.Methods The hBMSC were separated and cultured,and randomly divided into 2 groups.In first week,osteoblast-induced fluids was added into cultured hBMSC.Then in 2nd week,the CS containing osteoblast induced fluid and non-CS containing osteoblast-induced fluid were added into the test group and control group respectively.On the 14th day,RNA was extracted from the cultured cells,purification and quality test were performed.After cDNA was synthesized,quantitative real-time polymerase chain reaction(qRT-PCR) was used to examine the differently BMP-2 and VEGF between 2 groups.After hBMSC grew on the cover glass,they were induced with CS containing or conventional osteoblast-induced fluids,and observed the mineralized nodus formation with FITC dyes under fluorescent microscope.Results It was found that cells in both groups grew well and prolife rated gradually,cell growth and mineralized nodus formation had no significant difference between 2 groups under phasecontrast microscope or fluorescent microscope.However,BMP-2 and VEGF relative expression value in experimental group was higher than those in control group(P 0.05).Conclusion It is demonstrated that CS has potential osteoinductive activity and could promote bone formation,which may be related to the up regulation of osteoblastic gene expression.