Harmine promotes periodontal ligament cell-induced tissue regeneration.
to investigate whether harmine has a promotive effect on human periodontal ligament cells (hPDLCs)-induced tissue regeneration. Various concentrations of harmine on hPDLCs proliferation were tested. Osteogenic and cementogenic characteristics were examined in hPDLCrhBMP-2 and hPDLCharmine by alizarin red S staining, real-time PCR, and Western blotting assay. The activity of harmine was investigated in an ectopic transplantation nude mouse model. We determined that 10 μM of harmine was the threshold concentration. hPDLCharmine showed similar mineralized nodule formation in alizarin S staining compared to hPDLCrhBMP-2. In real-time PCR, the highest gene expression level was observed for Runx2 in hPDLCharmine at all time points. The level of CEMP-1 in hPDLCharmine was higher at 7 days than hPDLCs alone. Thicker band of Runx2 in hPDLCharmine was observed than in hPDLCrhBMP-2 at 7 days by Western blotting. The band for CEMP-1 in hPDLCharmine was thicker than hPDLCs alone at both 7 and 14 days. In ectopic transplantation, hPDLCs with harmine showed a comparable amount of mineralized tissue formation compared to rhBMP-2. hPDLCs with harmine or rhBMP-2 formed both bone and cementum-like tissue with Sharpeys fiber-like collagen insertion. Harmine can be a potential candidate for promoting hPDLCs-induced tissue regeneration.