R.T.R® promotes bone marrow mesenchymal stem cells osteogenic differentiation by upregulating BMPs/SMAD induced cbfa1 expression.

Bone marrow mesenchymal stem cells (BMSCs) of rats were isolated and Bio-Oss® and R.T.R® materials were used in this study.Alkaline phosphatase (ALP) activity in each group was calculated. The ability of adhesion and proliferation of BMSCs on Bio-Oss® and R.T.R® increased with time, but they were significantly higher on R.T.R® than that of Bio-Oss® at all time points (p<0.05). Compared with Bio-Oss®, R.T.R® could promote the expression and activity of ALP in BMSCs, and the expression of bone formation related transcription factors bone morphogenetic protein-1 (BMP-1), Cbfa1 and osteoblast marker genes ALP, collagen I, osteopontin, osseomucin and osteocalcin. The expression levels of cbfa1, ALP, collagen I, osteopontin, osseomucin and osteocalcin were inhibited after downregulated expression of BMP-1 in BMSCs and inoculation with R.T.R®. R.T.R® could up-regulate BMP-1 expression and cbfa1 expression through BMPs/SMAD signaling pathway, thereby promoting the expression of ALP, collagen I, osteopontin, osseomucin and osteocalcin and promoting osteoblast differentiation.