Protease-Activated Receptor Type 1 Activation Enhances Osteogenic Activity in Human Periodontal Ligament Stem Cells.

Protease-activated receptor 1 (PAR) has been associated to tissue repair and bone healing. The aim of the present study was to evaluate the effect of PAR activation on the osteogenic activity of human periodontal ligament stem cells (PDLSCs). PDLSCs were cultured in the presence of PAR-selective agonist peptide (100 nM), thrombin (0.1 U/mL), or PAR antagonist peptide (100 nM). Calcium deposits, calcium concentration (supernatant), alkaline phosphatase activity (ALP), cell proliferation, and gene (qPCR) and protein expression (ELISA assay) of osteogenic factors were assessed at 2, 7, and 14 days. PAR activation led to increased calcium deposits ( < 0.05), calcium concentration ( < 0.05), ALP activity ( < 0.05), and cell proliferation ( < 0.05). Further, PAR activation may increase gene and protein expression of Runx2 ( < 0.05) and OPG ( < 0.05). In conclusion, PAR activation increases osteogenic activity of PDLSCs, providing a possible new strategy for periodontal regenerative therapies.