PM2.5对HTR8-SVneo细胞的毒性作用

目的：探讨大气中的PM2.5对HTR8-SVneo细胞的毒性作用。方法：采用0，30，60，120和200 μg/mL 5个浓度的PM2.5对HTR8-SVneo细胞染毒24 h，以0 μg/mL浓度为对照组，其余浓度为不同剂量PM2.5染毒组，通过CCK-8细胞增殖毒性检测试剂盒测定细胞存活率；激光全息细胞分析及成像系统观察细胞3D形态及动态监测24 h内各组细胞数量变化；流式细胞仪检测细胞生长周期；彗星试验检测细胞DNA损伤水平；活性氧簇（ROS）检测试剂盒测定细胞内ROS水平。结果：60，120和200 μg/mL浓度组细胞存活率及增殖能力低于对照组（P＜0.05或P＜0.01）；PM2.5可使HTR8-SVneo细胞的生长周期阻滞在G2/M期（P＜0.05或P＜0.01）；不同浓度PM2.5染毒组彗尾DNA百分比均高于对照组（P＜0.01），且呈剂量依赖性。各浓度染毒组细胞中ROS的产生均高于对照组（P＜0.05或P＜0.01）。结论：PM2.5对 HTR8-SVneo细胞有一定毒性作用，造成DNA的损伤，阻碍细胞生长周期，这种毒性作用可能与氧自由基的产生增多有关。

Cytotoxicity of PM2.5 on HTR8-SVneo Cells

Objective: To investigate the cytotoxicity of atmospheric PM2.5 on HTR8-SVneo cells. Methods:The in vitro cultured HTR8-SVneo cells were exposed to PM2.5 at the concentrations of 0, 30, 60, 120 and 200μg/mL for 24 h. The cells treated with 0μg/mL PM 2.5 were used as the control group. The cell survival rate was analyzed by the CCK-8 cell proliferation and cytotoxicity test kits. The 3D morphology was observed by the Laser holographic cell analysis and imaging system. The change in the number of cells was also dynamically monitored. The cell cycle was detected by flow cytometry. The level of DNA damage was detected by comet assay. The level of intracellular reactive oxygen species (ROS) was measured by the ROS kits. Results:The survival rate and proliferation ability in three groups treated with 60, 120 and 200 μg/mL PM2.5 were significantly lower than those in the control group (P<0.05 or P<0.01). PM2.5 treatment made the growth cycle arrest in G2/M phase (P<0.05 or P<0.01). The percentage of tail DNA in the PM2.5 exposure groups was higher than that in the control group (P<0.01), with a dose-dependent manner. The level of ROS in the PM2.5 exposed groups was higher than that in the control group (P<0.05 or P<0.01). Conclusions: PM2.5 has a certain cytotoxicity on HTR8-SVneo cells via the DNA damage and the cell cycle arrest which is related to the increased oxygen free radicals.