Effect of recombinant connective tissue growth factor on proliferation and odontogenic differentiation of dental pulp cells

PURPOSE To analyze the effect of recombinant connective tissue growth factor(rCTGF) on proliferation and differentiation of human dental pulp cells(hDPCs). METHODS Human dental pulp cells were cultured in vitro and treated with rCTGF at different concentrations (0, 1, 10, 100 ng/mL). The proliferation of dental pulp cells was detected by CCK8 assay. The formation of mineralized nodules was determined by alizarin red staining and half-quantitative alizarin Red S assay. qRT-PCR was utilized to detect the expression of odontogenic differentiation related genes DMP-1, DSPP and OC, and the phosphorylation level of ERK1/2 signaling pathway was detected by Western blot. The data were analyzed with SAS 9.3 software package. RESULTS High concentration of rCTGF(100 ng/mL) could promote proliferation of dental pulp cells. After mineralization induction, 10 g/mL rCTGF had the best effect on promoting the formation of mineralized nodules in dental pulp cells, and calcium ion deposition was the most obvious(P<0.05). The expression of odontogenic differentiation related genes DMP-1 and DSPP was significantly up-regulated(P<0.05). Western blot results showed that hDPCs stimulated by 10 ng/mL rCTGF could increase the expression of p-ERK1/2. CONCLUSIONS rCTGF may promote the proliferation and differentiation of human dental pulp cells through activating ERK1/2 signaling pathway.