Effects of cadmium on proliferation,apoptosis,differentiation and mineralization in osteoblast in vitro

Purpose To investigate the effects of cadmium on proliferation,apoptosis,differentiation and mineralization in osteoblast in vitro. Methods The osteoblastic cells were harvested by sequential enzyme digestion from calvaria of Sprague Dawley rats and then cultured.They were treated with Cd2+,then the proliferation was analyzed by MTT methods;cell apoptosis was observed by fluorescence microscopy-acridine orange/ethidium bromide double staining;PNPP method was used to assay the ALP activity of osteoblastic cell;to analyze the mineralization ability of osteoblastic cells,the number and area of mineralization nodes were observed. Results Cd2+(2.0-32 μmol/L) significantly inhibited the proliferation of osteoblastic cells(P0.01);cell apoptosis was observed in the osteoblastic cells exposed to 16.0 μmol/L and 32.0 μmol/L Cd2+;Cd2+ inhibited the ALP activity at 24 h,48 h and 72 h,particularly at 48 h and 72 h(P0.01);Cd2+ significantly inhibited osteoblast mineralization at the concentration of 0.5 μmol/L and 1.0 μmol/L. Conclusions Cd2+ significantly inhibits boneformation of osteoblastic cells by inhibiting the proliferation,differentiation and mineralization of osteoblastic cells and promoting osteoblastic apoptosis.