Calcium Ions Released from Mineral Trioxide Aggregate are Taken Up by C2C12 Cells via the L-Type Voltage-Dependent Calcium Channel

Abstract

Mineral trioxide aggregate (MTA) is a commonly used endodontic repair material reported to exhibit calcified-tissue conductive activity. The effect of MTA on osteoblast differentiation has been well-defined; however, its effect on mesenchymal cells is not fully understood. Recently, we reported that MTA converts the differentiation pathway of pluripotent mesenchymal cells (C2C12 cells) into osteoblast lineages, possibly through the influx of elution components, such as calcium ions released from MTA. The purpose of this study was to investigate whether calcium ions released from MTA flow directly into C2C12 cells and whether this influx increases intracellular calcium levels. C2C12 cells were loaded with fluo-3 acetoxymethyl ester, which acts as a calcium-sensitive fluorescent probe. The intracellular calcium levels of C2C12 cells were assessed by confocal laser scanning microscopy. MTA induced a rapid increase in fluorescence intensity (FI) in C2C12 cells; however, application of Dulbecco's modified Eagle's medium (DMEM) as the growth medium had no such effect. To clarify the specific effects of MTA-derived calcium ions, we used calcium chloride as an exogenous calcium ion source and ethylene glycol tetraacetic acid (EGTA) as a calcium chelator. DMEM containing calcium chloride elicited a rapid rise in FI, whereas MTA plus EGTA did not affect FI. Moreover, MTA did not affect FI in C2C12 cells pre-incubated with verapamil, an L-type voltage-dependent calcium channel (VDCC L ) blocker. Our data suggest that calcium ions released from MTA flow directly into C2C12 cells via VDCC L .

Effect of Modified Bioceramic Mineral Trioxide Aggregate Cement with Mesoporous Nanoparticles on Human Gingival Fibroblasts

“…In particular, the increase in the concentration of calcium ions guides cells through mitosis via different mechanisms such as nuclear envelope breakdown, chromosome condensation, spindle fiber formation, and sister chromatid separation [54]. In MTA, calcium ions are present as calcium oxide which reacts with tissue fluids, forming calcium hydroxide [56]. Studies that have evaluated the effect of increasing the concentration of calcium ions in MTA have found that there is a limit to the effect of calcium ions on cellular mineralization [57,58].…”

Thermal, chemical and physical analysis of VDW.1Seal, Fill Root ST, and ADseal root canal sealers

“…Moreover, the alkaline pH provides bacteriostatic effects 45 and can promote apical healing and tissue mineralization 36 . Whereas the release of calcium ions, which are strong extracellular signals for undifferentiated cells 46 , is important for healing of apical periodontitis associated with bone resorption. Results of our study showed that VDW.1Seal exhibited the highest alkalinity and the highest cumulative calcium ion release compared to the other sealers at the end of the observation period ( p ≤ 0.05).…”