铀矿尘对RAW264.7细胞的氧化损伤作用

Effects of oxidative damage in RAW264.7 macrophage cells induced by uranium dusts

目的探讨铀矿尘作用于小鼠RAW 264.7细胞一定时间后羟自由基(.OH)、过氧化氢(H2O2)及丙二醛(MDA)含量的变化。方法用120μg/ml的铀矿尘混悬液作用于小鼠RAW264.7细胞,分别在作用2、4、8、16、24和32 h后,采用噻唑蓝比色法(MTT法)检测RAW264.7细胞存活率;HE染色镜下观察细胞形态学变化;比色法测定细胞上清液中.OH、H2O2及MDA含量的改变。结果铀矿尘作用于RAW264.7细胞2、4、8、16、24、32 h后,可见铀矿尘对RAW264.7细胞的增殖有明显抑制作用,染尘32 h后细胞存活率仅有(28.37±3.3)%;铀矿尘在作用于RAW264.7细胞16、24、32 h后,镜下可见梭型或不规则型细胞、多核细胞明显增加,细胞胞质缺失,胞核外露和染色变浅,细胞数目明显减少;铀矿尘处理的细胞上清液中.OH、H2O2及MDA在染尘后24 h达到峰值,分别为(94.05±4.72)U/ml、(68.83±4.34)mmol/L、(5.67±0.29)nmol/ml,与对照组比较,差异有统计学意义(P<0.01)。结论铀矿尘可明显抑制RAW264.7细胞的增殖作用,导致细胞死亡数量增多。可引起细胞上清液中.OH、H2O2及MDA含量增高,对RAW264.7细胞具有氧化损伤作用。

[Objective]To explore the changes of·OH,H2O2 and MDA levels in RAW264.7 murine macrophage cells after exposure to uranium dusts for a certain period of time.[Methods]RAW264.7 murine macrophage cells were treated with uranium dust in aqueous suspension 120 μg/ml.After treatment for 2,4,8,16,24 and 32 h,the rate of survival RAW264.7 was measured with MTT method.Morphological changes were observed by microscope in HE staining.The levels of ·OH、H2O2 and MDA in extracellular were detected by colorimetric method.[Results] Treated with 120 μg/ml uranium dust suspension for 2,4,8,16,24 and 32 h,the proliferation of RAW264.7 cells was significantly suppressed with time-dependent manner,the rate of survival was（28.37±3.3）% after 32 h.At treated 16,24 and 32 h,the increase of the number of spindle cells,irregular cells or multinucleated cells,the significant reduction of the number of cells and morphological changes including cytoplasm lost,nuclei exposed and light staining in cells were observed.The levels of ·OH,H2O2 and MDA in cultured supernatant in uranium dust treated groups were（94.05±4.72） U/ml,（68.83±4.34） mmol/L,（5.67±0.29） nmol/ml after 24-h-treatment,respectively which were significantly different with those of the control group（P0.01）.[Conclusion]The uranium dust can inhibit the proliferation activity of RAW264.7 cells and cause cell death significantly.Uranium dust can increase the levels of ·OH,H2O2 and MDA in cultured supernatant,and induce the effects of oxidative damage in RAW264.7 macrophages.