Quantitative measurements of the generation of hydroxyl radicals by soot particles in a surrogate lung fluid
Quantitative measurements of the generation of hydroxyl radicals by soot particles in a surrogate lung fluid
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DOI：
10.1016/j.atmosenv.2005.11.015
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发表时间：
2006-02-01
影响因子：
5
通讯作者：
Kennedy, IM
中科院分区：
文献类型：
--
作者：
Jung, H;Guo, B;Kennedy, IM
流行病学和毒理学研究表明，吸入大气颗粒物与对心肺健康的不利影响之间存在联系。颗粒物产生活性氧（ROS）是其毒性作用的一种当前假说。因此，ROS的定量测量是重要的，因为这将是评估颗粒可能在肺中引起的氧化应激的指标。我们开发了一种技术，用于定量和特异性地测量水性缓冲提取液（作为替代肺液（SLF））中的（OH）-O-中心点（最强的生物活性氧）。使用这种技术，我们定量测量（OH）-O-中心点形成在SLF含有过氧化氢（HOOH）的样品的火焰烟灰颗粒，炭黑，和周围的细颗粒物（PM2.5）。我们发现，（OH）-O-中心点是由火焰煤烟形成的，与过渡金属无关，具有依赖于HOOH浓度的剂量依赖性线性响应。用炭黑进行的实验表明，其质量归一化（OH）-O-中心点的生成比火焰烟灰的生成低10倍，这表明炭黑在健康影响研究中不是烟灰颗粒的良好替代物，至少在氧化应激方面是这样。由环境PM2.5产生的质量归一化（OH）-O-中心点比火焰烟灰大6-30倍。虽然大部分的PM2.5的反应性被抑制预处理样品与过渡金属螯合剂，有一个显着的分数的反应性不受影响。我们的研究结果表明，在体内产生的自由基，特别是（OH）-O-中心点，通过吸入PM2.5部分是由于碳烟以及过渡金属。(c)2005爱思唯尔有限公司保留所有权利。
Epidemiological and toxicological studies have shown a relation between the inhalation of atmospheric particles and adverse cardiopulmonary health effects. The generation of reactive oxygen species (ROS) by particles is one current hypothesis for their toxic effects. Thus a quantitative measurement of ROS is important since that will be an index to assess the oxidative stress that particles may cause in the lung. We have developed a technique to quantitatively and specifically measure (OH)-O-center dot (the strongest biological ROS) in an aqueous, buffered extract solution as a surrogate lung fluid (SLF). Using this technique we quantitatively measured (OH)-O-center dot formation in SLF containing hydrogen peroxide (HOOH) for samples of flame soot particles, carbon black, and ambient fine particles (PM2.5). We have found that (OH)-O-center dot is formed by flame soot, independent of transition metals, with a dose-dependent linear response that depends upon HOOH concentration. Experiments with carbon black revealed that its mass-normalized (OH)-O-center dot generation was similar to 10 times lower than that of flame soot, suggesting that carbon black is not a good surrogate for soot particles in health effect studies, at least in terms of oxidative stress. Mass-normalized (OH)-O-center dot generation by ambient PM2.5 was 6-30 times larger than that of flame soot. While much of the PM2.5 reactivity was suppressed by pretreating samples with a transition metal chelator, there was a significant fraction of reactivity which was not affected. Our results suggest that the in vivo generation of free radicals, specifically (OH)-O-center dot, by inhalation of PM2.5 is partially due to carbonaceous soot as well as transition metals. (c) 2005 Elsevier Ltd. All rights reserved.