A comparative analysis of the effect of BMP-2 and TNF-alpha( TNF-α) on osteoblast proliferation and differentiation

Objective To investigate the effect of BMP-2 and TNF alpha( TNF-α) on osteoblast proliferation and differentiation and a comparative analysis was to be done. Methods Wistar rat( 1 week old) skull waschipped by the surgery done under sterile conditions and osteoblasts were extracted,cultured,passed,purified and amplified. Different concentrations of BMP-2 and TNF-α were used to induce rat osteoblasts. Methyl thiazolyl tetrazolium( MTT) assay was used to detect the proliferation of osteoblasts,and PP-nitrophenyl phosphate( PNPP) was used to detect the alkaline phosphatase( ALP) activity of osteoblasts. Results Cells stained and calcified by ALP were both positive,which has proven that the cells cultured in vitro have the typical characteristics of mature osteoblasts. Rat osteoblast proliferation activity and ALP activity increased with the increase of BMP-2 concentration,but decreased with the increase of TNF-α concentration,and the differnce was statistically significant( P 0. 05). Conclusions Transfection of BMP-2 can improve the proliferation and differentiation of osteoblasts. TNF-α has inhibitory effect on the proliferation and differentiation of osteoblasts. BMP-2 and TNF alpha respectively promote and inhibit in vitro culture of osteoblasts through different mechanisms.