沙尘暴细颗粒物对大鼠肺泡巨噬细胞钙水平和脂质过氧化的影响

Effects of dust storm fine particles on the calcium level and lipid peroxidation of rat alveolar macrophages

2 0 0 4年3月采集甘肃省武威市和内蒙古包头市正常良好天气、局地扬沙天气和沙尘暴天气的大气细颗粒物(PM2 5 )样品.以不同浓度的细颗粒物悬液体外处理大鼠肺泡巨噬细胞后测定细胞内丙二醛(MDA)、谷胱甘肽(GSH)及胞质游离Ca2 + 含量,并观察不同处理时间的细胞存活率.研究结果表明:(1)沙尘暴与非沙尘暴PM2 5均使细胞内MDA和Ca2 + 含量升高、GSH含量下降,且对细胞毒性存在时间效应和剂量 效应关系.(2 )PM2 . 5对各指标的影响仅与处理剂量有关,而与样品种类无关.沙尘暴期间大气PM2 5浓度很高,因而沙尘暴PM2 . 5的危害作用不可忽视.

A study was conducted to investigate the hazards of dust storm fine particulate matter PM2.5 (particles of ≤2.5?μm in aerodynamic diameter)on rat alveolar macrophages (AM), based on the ambient PM2.5 collected in March 2004 from Wuwei city, Gansu Province and Baotou city, Inner Mongolia Autonomous Region. The collected particles were classified as normal, local blowing sand, and dust storm samples. And the mass concentration of airborne PM2.5 during sampling periods was also determined. The level of malondialdehyde (MDA), glutathione (GSH) and cytosolic free calcium ions (Ca 2+) of AM were determined following the in vitro treatment of AM with different concentrations of the collected samples. The cytotoxicity was assessed by using the 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) reduction assay. The results revealed that the concentration of PM2.5 exceeding 300?μg·mL -1 among the normal, blowing sand, and dust storm led to an increase (P<0.05) in cellular MDA and Ca 2+ levels, and a decrease (P<0.05) in GSH levels, which appeared cell viability in a dose-response manner with respect to the control. It is also found that deleterious effect of PM2.5 close response to the concentration rather than the type of particles, due to the above indices showed were no significant difference between the different classes of PM2.5 (normal, blowing sand, and dust storm samples) from both cities. It was also believed that a much more serious effect on AM was imminent due to a higher dose of airborne PM2.5 during blowing sand and dust storm episodes. It concluded that appropriate attention should be focused on the toxicity of dust storm PM2.5 particles.