Effect of rhBMP-2 on mineralization of human periodontal ligament cells under high glucose conditions in vitro

This study was performed to investigate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) during mineralization of human periodontal ligament (hPDL) cells in high glucose conditions. The hPDL cells were cultured in 1000 mg/L d-glucose (normal glucose group) or 4500 mg/L d-glucose (high glucose group) and exposed to rhBMP-2 at concentrations of 0, 50, 100, 300, and 500 ng/mL. MTT assays were performed on days 4 and 7. Alkaline phosphatase (ALP) activity was measured on day 10. On day 28, cells that were stained with alizarin red S and calcium deposition were measured. On days 4 and 7, rhBMP-2 inhibited mitochondrial activity dose-dependently in both groups. On day 10, ALP activity was increased by rhBMP-2 dose-dependently in both groups and had a tendency to inhibit ALP activity in high glucose groups. On day 28, mineralized nodule formation and calcium deposition were increased by rhBMP-2 dose-dependently in both groups and were inhibited at the lower concentration of rhBMP-2 (under 100 ng/mL) but markedly increased at a higher concentration of rhBMP-2 (300 and 500 ng/mL) in high glucose groups. We concluded that it was important to establish the appropriate concentration of rhBMP-2 for the treatment of periodontal disease in diabetic patients.