中文摘要：

目的探讨机动车排放PM2.5对EA.hy926细胞（人脐静脉内皮细胞和人肺腺癌细胞株A549融合的细胞株）增殖功能、DNA甲基化及凋亡的影响。方法机动车排放PM2.5对EA.hy926细胞染毒24 h。采用MTS法测定机动车排放PM2.5对细胞增殖功能的影响;DNA甲基化定量检测试剂盒（比色法）测定机动车排放PM2.5对细胞DNA甲基化的影响;Annexin V-FITC/PI染色,流式细胞仪测定机动车排放PM2.5对细胞凋亡的影响。结果机动车排放PM2.5染毒24 h可抑制细胞增殖功能,当染毒质量浓度为200μg/m L时,与PBS对照组比较差异有统计学意义（P〈0.05）;随着染毒质量浓度的增加细胞DNA甲基化率（5-m C%）下降,在染毒质量浓度为50μg/m L和200μg/m L时,与PBS对照组比较差异有统计学意义（P〈0.05）;随染毒质量浓度升高细胞诱导凋亡率逐渐升高。结论机动车尾气排放PM2.5可以抑制EA.hy926细胞的增殖功能,改变EA.hy926细胞的DNA甲基化率,对EA.hy926细胞产生诱导凋亡作用。此外DNA甲基化可能是细胞增殖和凋亡的机制,定点基因的甲基化仍需要进一步研究。

英文摘要：

Objective To investigate the proliferative function,DNA methylation and apoptosis of EA. Hy926 cells induced by PM2. 5discharged from motor vehicles. Methods EA. Hy926 cells were exposed to PM2. 5discharged from motor vehicles for 24 h,the proliferative function of cells was determined by MTS method,the DNA methylation of cells was determined by test kits（ colorimetric method）,and the apoptosis of cells was stained by Annexin V-FITC / PI and detected by flow cytometry. Results Compared with the control group,the proliferative function of EA. Hy926 cells was suppressed after 24 h of PM2. 5exposure in the 200 μg / m L group（ P〈0. 05）; the methylation of EA. Hy926 cells（ 5- m C%） was significantly decreased after 24 h of exposure to PM2. 5in the 50 and 200 μg / m L group（ P〈0. 05）; the apoptosis of EA. Hy926 cells was increased with the rise of PM2. 5concentration. Conclusions The exposure of PM2. 5discharged from motor vehicles could inhibit the proliferation of EA. Hy926 cells,decrease the level of 5- m C% in EA. Hy926 cells and induce the apoptosis of EA. Hy926 cells,and the decrease of DNA methylation might be the mechanism for inhibited proliferation of EA. Hy926 cells and the apoptosis of EA. Hy926 cells.