城市不同源雾霾颗粒物健康风险差异评估比较

通过研究不同来源霾颗粒物对大鼠气管上皮细胞（RTE cells）电阻抗变化和细胞自噬因子的影响，评价不同来源霾颗粒物对人体健康风险的差异性.分别将RTE暴露于从居民区（I），高架交通源（Ⅱ）和化工园区（Ⅲ）采集的3种雾霾颗粒物中，统一暴露浓度和时间分别为100mg/L和24h.通过电子细胞基质阻抗检测（ECIS）细胞增长引起的阻抗变化和细胞电损伤恢复时间；通过蛋白免疫印迹测定p62，Atg5，Atg7，Beclin1，LC3B和mTOR蛋白表达量来分析比较不同来源雾霾颗粒物对RTE细胞自噬的影响.结果表明，与空白对照组相比，不同雾霾颗粒物处理组细胞电损伤恢复时间分别延长了34.6%，63.2%和78.0%；p62蛋白表达量差异显著性下降，Atg5，Atg7，Beclin1，LC3B蛋白表达量差异显著性上升.此外，mTOR相关蛋白表达量差异显著性下降，分别下降了4.38%，3.34%和2.36%；p-mTOR蛋白表达量与空白组相比，实验组I下降24.2%，实验组Ⅱ下降37.0%，实验组Ⅲ下降60.9%.由以上结果可知，不同来源雾霾颗粒物对RTE细胞均有一定的毒性损伤作用，能够减小细胞增长速度和削弱细胞修复能力，增强细胞自噬因子蛋白的表达，且化工园区采集的雾霾颗粒物毒性强于居民区和高架交通源.不同来源雾霾颗粒物的细胞毒性存在明显差异，基于细胞电损伤恢复时间的测定以及自噬相关蛋白的检测方法能够为雾霾颗粒物健康风险评价提供一种快速的生物学手段.

Comparison and assessment of haze particles health risks from different sources in city

To evaluate the health risks induced by haze particles sampled from three different areas. The present study assessed the effects of haze particles on electrical impedance and autophagy factors of the tracheal epithelial cells. Rat tracheal epithelial (RTE) cells were exposed to haze particles collected from three different areas, including residential area (I), traffic area (Ⅱ), and chemical industry park (Ⅲ) in the megacity Hangzhou, China. The particle concentration was treated and designed as 100mg/L and then a period of 24h exposure was given to cells in treatment groups. The electronic impedance and the time needed for the recovery of electricity damage were determined by ECIS (Electric Cell-substrate Impedance Sensing). Western blot was used to analyze the protein expressions of p62, Atg5, Atg7, Beclin1, LC3B and mTOR to compare the effects of different haze particles on RTE cells autophagy. The results showed that the recovery time of cell injury was prolonged by 34.6%, 63.2% and 78.0%, respectively, when compared with the control group. The expression of Atg5, Atg7, Beclin1and LC3B proteins increased, whereas that of p62protein significantly decreased. The expression of mTOR related proteins decreased significantly by 4.38%, 3.34% and 2.36%, respectively. Compared with the control group, the expression of p-mTOR decreased by 24.2% in group I, 37.0% in group Ⅱ and 60.9% in group Ⅲ. All the results suggested that haze particles collected from different functional areas could induce various toxic damages on RTE cells such as reduction of growth speed, impairment of revovery ability, and increased authophagy protein expression. The haze particles from chemical industrial areas showed more toxic effects than those from residential areas and traffic areas. The cytotoxicity of haze particles from different sources is obviously different The determination of cell electrical injury recovery time and the detection of autophagy-related proteins can provide a rapid biological method for health risk assessment of haze particles.