Abstract:

Objective The cementum mineralization is important for cementum repair after root resorption. This study aims to investigate the role of Wnt/β-catenin signaling pathway in regulating the mineralization of cementocyes under mechanical stress. Methods The IDG-CM6 cells were subjected to osteogenic-induced medium for 21 days and then harvested for establishing in vitro mechanical loading model for 6 h. RNA-seq technique was used to screen the differentially expressed genes in IDG-CM6 cells under stress. Alizarin red staining was applied to observe the mineralization of IDG-CM6 cells, and the expression levels of β-catenin and osteogenic factors, Runx2 and Osterix, were detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)and Western blot. The expressions of β-catenin and Runx2 were also observed by immunofluorescence staining. After knockdown of β-catenin in IDG-CM6 cells by siRNA technology, the mineralization of IDG-CM6 cells and the expression levels of Runx2 and Osterix were detected under mechanical stress. Results The mineralization of IDG-CM6 cells and the expression levels of Runx2 and Osterix were increased under mechanical stress. The bioinformatic analysis, RT-qPCR, Western blot and immunofluorescence staining showed that mechanical stress could promote β-catenin expression and knockdown of β-catenin could reverse the mineralization promotion effect produced by mechanical stress. Conclusion Wnt/β-catenin pathway is involved in the regulation of cementum mineralization and plays an important role in cementum mineralization after root resorption.

Key words: cementocyte, cementum homeostasis, Wnt/β-catenin signaling pathway, mineralization