铅暴露对成骨细胞MC3T3-E1细胞线粒体的影响

Effects of lead exposure on mitochondria of osteoblast MC3T3-E1

目的评价铅暴露对成骨细胞MC3T3-E1线粒体的影响。方法在MC3T3-E1细胞培养瓶中加入不同浓度醋酸铅[Pb(Ac)2]溶液(0、1、10、100μmol/L)培养24 h后,分别测定其线粒体膜电位去极化程度与ATP合成量、胞浆与线粒体内细胞色素c含量以及Caspase-3活性,并利用透射电镜观察细胞线粒体形态变化。结果铅暴露可致成骨细胞MC3T3-E1线粒体膜电位降低,ATP合成减少,细胞内细胞色素c从线粒体到胞浆的释放增加,Caspase-3活性增强,并且呈明显剂量依赖关系。此外,电镜观察可见100μmol/L醋酸铅暴露组细胞线粒体明显肿胀。结论铅暴露可引起成骨细胞MC3T3-E1线粒体功能与结构损伤,从而导致细胞凋亡。

Objective To evaluate the effect of lead exposure on mitochondria of osteoblasts MC3 T3-E1. Methods Osteoblasts MC3 T3-E1 with different concentrations（ 0,1,10,100μmol/L） of lead acetate[Pb（ Ac） 2] solution were incubated for 24 h. After that,the degree of depolarization of mitochondrial membrane potential,the amount of ATP synthesis,cytochrome c content in cytoplasm and mitochondria and Caspase-3 activity were measured. In addition,the morphological changes of mitochondria were observed by transmission electron microscope. Results Lead exposure can cause the decrease of mitochondrial membrane potential,the decrease of ATP synthesis in osteoblasts,Ithe release of cytochrome c from mitochondria to cytoplasm and the increase of Caspase-3 activity in MC3 T3-E1 cells. All results are significantly dosedependent. n addition,through electron microscopy observation,it was found that the mitochondria in exposure of 100 μmol/L lead acetate swelled obviously. Conclusion Lead exposure can cause the functional and structural damage of MC3 T3-E1 mitochondria and thus result in apoptosis.