Harmine promotes periodontal ligament cell-induced tissue Regeneration

Abstract

OBJECTIVE to investigate whether harmine has a promotive effect on human periodontal ligament cells (hPDLCs)-induced tissue regeneration. MATERIALS AND METHODS Various concentrations of harmine on hPDLCs proliferation were tested. Osteogenic and cementogenic characteristics were examined in hPDLC/rhBMP-2 and hPDLC/harmine 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. RESULTS We determined that 10 μM of harmine was the threshold concentration. hPDLC/harmine showed similar mineralized nodule formation in alizarin S staining compared to hPDLC/rhBMP-2. In real-time PCR, the highest gene expression level was observed for Runx2 in hPDLC/harmine at all time points. The level of CEMP-1 in hPDLC/harmine was higher at 7 days than hPDLCs alone. Thicker band of Runx2 in hPDLC/harmine was observed than in hPDLC/rhBMP-2 at 7 days by Western blotting. The band for CEMP-1 in hPDLC/harmine 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 Sharpey's fiber-like collagen insertion. CONCLUSION Harmine can be a potential candidate for promoting hPDLCs-induced tissue regeneration.