Calcium overload and reactive oxygen species mediate high glucose-induced apoptosis of mouse osteoblast MC3T3-E1 cells

AIM: To investigate the role of reactive oxygen species(ROS) and calcium overload in the apoptosis of MC3T3-E1 cells induced by high glucose.METHODS: Cultured mouse skull bone-derived osteoblast cell line MC3T3-E1 was treated with high concentration of D-glucose to induce apoptosis.The proliferation of MC3T3-E1 cells was detected by MTT assay after treated with different concentrations of D-glucose for 24 h and 48 h.The apoptotic rate and the intracellular levels of calcium and ROS were also measured after the cells were treated with high glucose(35 mmol/L) for 24 h.RESULTS: After high glucose treatment,the cell proliferation was inhibited.The early apoptosis and total cell death increased to(24.16±3.53)% and(63.74±4.32)%,respectively.High glucose treatment significantly increased intracellular levels of ROS and Ca2+.The increased apoptotic rate was reduced by addition of antioxidant N-acetylcysteine and calcium chelator BAPTA-AM.Inhibition of store-operated Ca2+ channels by La3+ also decreased the intracellular level of Ca2+ and cell apoptosis induced by high glucose.CONCLUSION: High glucose increases intracellular ROS level and the release of Ca2+ through the store-operated Ca2+ channels,thus resulting in intracellular Ca2+ overload and leading to apoptosis of osteoblasts.