沙尘暴细颗粒物致大鼠肺泡巨噬细胞DNA损伤

[目的]探讨沙尘暴和正常天气细颗粒物(PM2.5)及其水提取物和有机提取物对大鼠肺泡巨噬细胞的细胞毒性和DNA的损伤作用。[方法]沙尘暴和正常天气PM2.5于2004年3月采集自甘肃省武威市和内蒙古自治区包头市。细胞毒性用四甲基偶氮唑盐(MTT)分析法观察,细胞DNA损伤用单细胞凝胶电泳(SCGE)技术检测。[结果]沙尘暴和正常天气PM2.5及其水提取物和有机提取物均对大鼠肺泡巨噬细胞产生一定的细胞毒性,且随剂量的增大而增强;然而,沙尘暴与正常天气之间除了包头沙尘暴PM2.5有机提取物之外,余差异均无显著性。正常天气PM2.5和沙尘暴PM2.5水提取物和有机提取物均可引起细胞DNA损伤,且随剂量增加而损伤增大;正常天气PM2.5比沙尘暴PM2.5水提取物和有机提取物对细胞DNA损伤作用更大。不论正常天气PM2.5还是沙尘暴PM2.5,其有机提取物对DNA的损伤作用均比水提取物作用更强,表明PM2.5中引起DNA损伤的主要化学物是有机化合物种类。武威与包头两城市工业水平不同,大气污染程度不同,但两地沙尘暴PM2.5及其水提取物和有机提取物对细胞DNA的损伤作用,在两地之间并无明显差异。[结论]正常天气PM2.5和沙尘暴PM2.5及其水提取物和有机提取物均可引起DNA损伤,且正常天气PM2.5的损伤作用更强;然而不同地方沙尘暴PM2.5毒性作用未见差异,推测其所含遗传毒性化学物可能类似。

Damage Effects of Fine Particles from Sandstorm on DNA of Alveolar Macrophages in Rats

[ Objective] To study the toxicological effects of fine particles(PM2.5),water extract and solvent-extractable organic compounds of PM2.5 from sandstorm and normal weather on the viability and DNA of rat alveolar macrophages,respectively. [Methods] We collected these fine particulate matters in Wuwei city,Gansu Province,and Baotou city,Inner Mongolia Autonomous Region,in March,2004. DNA damage of rat alveolar macrophages was detected with single cell gel electrophoresis technique and cytotoxicity was assessed by 3(-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)reduction assay. [Results] PM2.5 water extract and solvent-extractable organic compounds from sandstorm and normal weather had cytotoxicity to alveolar macrophages and caused the cell viability decreased in a dose-response manner;however,no significant difference was observed between the sandstorm samples and the normal weather samples except for the Baotou sandstorm PM2.5 solvent- extractable organic compounds. The water extracts of both normal weather PM2.5 and sandstorm PM2.5 could lead to DNA damage in a dose-dependent manner;the water extract of normal weather PM2.5 made higher DNA damage than that of sandstorm PM2.5. The solvent-extractable organic compounds of both PM2.5 could lead to DNA damage and the solvent-extractable organic compounds of normal weather PM2.5 made higher DNA damage than that of sandstorm PM2.5. The solvent-extractable organic compounds made higher DNA damage than the water extract of both PM2.5. It was suggested that the organic compounds are the main contributor to make DNA damage. Though there is difference in air pollution between Baotou city and Wuwei city,no significant differences were observed in DNA damage of sandstorm PM2.5 both for its water extract and solvent-extractable organic compounds between two cities.[ Conclusion] Normal weather PM2.5 and sandstorm PM2.5 and their water extracts and solvent-extractable organic compounds all can lead to DNA damage in a dose-dependent manner;also our results suggest that the genotoxicity of sandstorm PM2.5 from these two cities is similar.