Involvement of the calcium-sensing receptor in mineral trioxide aggregate-induced osteogenic gene expression in murine MC3T3-E1 cells

Mineral trioxide aggregate (MTA) has excellent biocompatibility as well as bioactivity, including an ability to induce osteoblast differentiation. We examined the effects of the calcium-sensing receptor (CaSR) on osteogenic gene expression induced by MTA. MC3T3-E1 cells were cultured with or without (control) MTA. The expression levels of Runx2, type I collagen, and CaSR genes were analyzed by real-time polymerase chain reaction and their products were measured using enzyme-linked immunosorbent assays. The levels were increased significantly in cells exposed to MTA compared with control. Next, MC3T3-E1 cells were cultured with MTA and EGTA (a calcium chelator), because calcium ions were released continuously from MTA into the culture. Expression levels were decreased to control levels by MTA plus EGTA. NPS2143 (a CaSR antagonist) also reduced MTA-induced gene expression. These results suggest that MTA induced osteogenic gene expressions of Runx2 and type I collagen via CaSR in MC3T3-E1 cells.