Salvianolic acid B promotes the osteogenic differentiation of human periodontal ligament cells through Wnt/β-catenin signaling pathway

Background: Osteogenic differentiation of human periodontal ligament cells (hPDLCs) is crucial for regenerate periodontal tissues. In this study, we investigated the function of salvianolic acid B (Sal B) in osteogenesis of hPDLCs. Methods: HPDLCs were isolated from healthy third molar roots. HPDLCs at passage 3 were identified by morphological observation and immunohistochemistry of vimentin. The viability of hPDLCs incubated with Sal B at concentrations of 0 mu M, 0.1 mu M, 0.5 mu M, 1 mu M and 5 mu M were measured by CCK-8 assay. To evaluate the effect of Sal B on osteogenic differentiation of hPDLCs, the alkaline phosphatase (ALP) activity, osteogenic differentiation markers, and mineralized nodules were determined by ALP kit, qRT-PCR and alizarin red S staining, respectively. To confirm the function of Sal B in hPDLCs involved in Wnt/beta-catenin signaling pathway, hPDLCs were incubated with Sal B or co-incubated with Sal B and DKK-1 (a inhibitor of Wnt/beta-catenin). The levels of Wnt/beta-catenin signaling pathway and osteogenic differentiation-associated indicators were then determined. Results: HPDLCs showed a typical fibroblast-like and spindle-shaped, with vimentin-positive. The viability of hPDLCs had no obvious change with stimulation of Sal B at various doses. Sal B promoted the increase of ALP activity, osteogenic differentiation markers levels, mineralized nodules and activation of Wnt/beta-catenin signaling pathway, and DKK-1 could block those effects of Sal B on hPDLCs. Conclusion: Sal B promoted osteogenesis of hPDLCs through Wnt/beta-catenin signaling pathway, which providing a potential drug for periodontitis treatment.