Effects of Wnt/β-catenin signalling on proliferation and differentiation of apical papilla stem cells.

OBJECTIVES: The Wnt signalling pathway has been shown to play an important role in tooth development, however its effects with stem cells from the apical papilla (SCAP) have remained unclear. The purpose of this study was to determine effects of Wnt/β-catenin on proliferation and differentiation of SCAP in vitro.

MATERIALS AND METHODS: SCAP were obtained, identified and cultured. Cell proliferation, alkaline phosphatase (ALP) activity, mRNA expression of mineralization-related genes and mineralized nodule formation were measured in presence or absence of various concentrations of lithium chloride.

RESULTS: MTT assay and flow cytometry demonstrated that Wnt/β-catenin activity could promote proliferation of SCAP. Real-time PCR analysis found that Wnt/β-catenin strongly upregulated expression of dentine sialophosphoprotein, osteocalcin and ALP in SCAP after incubation with mineralization induction medium, while ALP and alizarin red staining indicated that Wnt/β-catenin enhanced ALP activity and formation of mineralized nodules.

CONCLUSION: Our results suggest that canonical Wnt/β-catenin signalling promotes proliferation and odonto/osteogenic differentiation of SCAP.