Effects of IGF-I and BMP-2 combined application on promoting proliferation, differentiation and calcification of MC 3T3-E1 and NIH 3T3 cells / 浙江大学学报·医学版

ABSTRACT

<p><b>OBJECTIVE</b>To demonstrate the effects of recombinant human insulin-like growth factor-I (rhIGF-I) and/or recombinant human bone morphogenetic protein-2 (rhBMP-2) on proliferation, differentiation and calcification of MC 3T3-E1 cells and NIH 3T3 cells.</p><p><b>METHODS</b>Mouse osteoblast-like cell line MC 3T3-E1 and mouse fibroblast cell line NIH 3T3 were treated with different dosages of rhIGF-I or rhBMP-2 and rhIGF-I plus rhBMP-2. Cell proliferation was measured by methylthiazol tetrazolium (MTT)method and flow cytometry. Cell differentiation was examined by using alkaline phosphatase(ALP)measurement kit. Radioimmunoassay was applied to detect levels of osteocalcin (OC) secreted by cultured cells. Von kossa staining method was used to study the calcification effects.</p><p><b>RESULTS</b>MC 3T3-E1 cells treated with 1-50 ng/ml rhIGF-I and NIH 3T3 cells treated with 5-75 ng/ml rhIGF-I showed marked effects of promoting proliferation (P<0.01), increasing the percentages of S-phase cells, decreasing the percentages of G1-phase cells and increasing activities of cellular ALP and percentages of calcification area (P<0.05). 10-100 ng/ml rhBMP-2 was also able to promote proliferation (P<0.01), increase the percentages of S-phase cells, decrease the percentages of G1-phase cells and enhancing cellular ALP activities and percentages of calcification area for both the two cells (P>0.05).</p><p><b>CONCLUSION</b>rhIGF-I and rhBMP-2 have synergistical effects on promoting cell proliferation, early cell differentiation and calcification depending on the used dosages, but no significant effects on promoting advanced cell differentiation.</p>