Effect of exogenous inhibition of Wnt signaling pathway on differentiation of human dental pulp cells into dentin induced by BMP-2

PU Tiemin; HAN Yakun

doi:10.3969/j.issn.1002-266X.2019.04.010

Abstract：Objective To investigate the effect of exogenous inhibition of Wnt signaling pathway on the differentiation of human dental pulp cells (HDPCs) into dentin induced by bone morphogenetic protein 2 (BMP-2). Methods HDPCs were randomly divided into the control group, induction group, and inhibitor treatment group. The cells in the control group were not treated. The BMP-2 induction solution was used in the induction group, and the Wnt inhibitors DKK-1 and BMP-2 induction solution were used in the inhibitor treatment group. The expression of β-catenin protein in the nuclei of each group was detected by Western blotting. We detected the alkaline phosphatase activity by PNPP azo method. The number of calcium nodules was detected by Von Kossa staining. The expression of dentin sialophosphoprotein (DSPP) and dentin matrix protein (DMP-1) in cells of each group was detected by real-time fluorescence quantitative PCR and Western blotting. Results Compared with the control group, the expression of β-catenin protein in the HDPC nuclei was down-regulated in the induction group and the inhibitor treatment group (P ＜ 0. 05), while ALP activity, the number of calcified nodules, DSPP and DMP-1 mRNA and protein expression were up-regulated (all P ＜ 0. 05). Compared with the induction group, the expression of β-catenin protein in the HDPC nuclei was down-regulated in the inhibitor treatment group (P ＜ 0. 05), while ALP activity, the number of calcified nodules, DSPP and DMP-1 mRNA and protein expression were up-regulated (all P ＜ 0. 05). Conclusion Exogenous inhibition of Wnt signaling pathway can promote the differentiation of HDPCs into dentin induced by BMP-2.