Chemical reactivity of the carbon-centered free radicals and ferrous iron in coals: role of bioavailable Fe2+ in coal workers pneumoconiosis.
Chemical reactivity of the carbon-centered free radicals and ferrous iron in coals: role of bioavailable Fe2+ in coal workers pneumoconiosis.
复制标题
煤炭中以碳为中心的自由基和亚铁的化学反应性：生物可利用的 Fe2 在煤工尘肺病中的作用。
DOI：
10.1080/10715769900300481
复制
发表时间：
1999
影响因子：
3.3
通讯作者：
Pezerat,H
中科院分区：
文献类型：
--
作者：
Huang,X;Zalma,R;Pezerat,H
不同矿区煤工尘肺患病率存在显著差异。造成所观察到的煤与水之间区域差异的主要因素尚未查明。本文用ESR技术研究了煤和肺组织中碳中心自由基以及煤中亚铁的化学反应性。ESR谱表明煤中至少存在两种碳中心自由基物种，它们可能分别来自煤的大分子相和分子相。研磨在煤中产生自由基。新磨煤暴露于空气中28 h后，大多数煤的自由基略有增加，暴露4个月后略有下降。煤工尘肺死亡工人肺组织ESR谱与煤样相似，自由基在肺组织中稳定性高。在用谷胱甘肽、过氧化氢、甲酸钠或氧气孵育煤之后，来自Gardanne矿的煤样品（其从未诱导CWP，因此是最不危险的煤）显示出以碳为中心的自由基浓度的最显著变化。在报告的其他煤中没有观察到显著的变化，以诱导CWP。另一方面，我们发现，煤释放不同数量的Fe 2+在酸性介质中。有趣的是，CWP的患病率与这些煤中释放的Fe 2+含量呈正相关，并与酸化煤中Fe 2+与O2相互作用产生的氧自由基的量呈正相关。我们的研究表明，以碳为中心的自由基可能与煤尘诱发的尘肺没有生物学相关性，而酸溶性Fe 2+可能溶解在巨噬细胞的吞噬溶酶体中，从而导致Fe 2+诱导的氧化应激和最终的CWP发展。
Striking differences in the prevalence of coal workers' pneumoconiosis (CWP) exist between different coal mine regions. The major factors responsible for the observed regional differences in CWP have not yet been identified. In the present study, chemical reactivity of the carbon-centered free radicals in coals and lung tissues, as well as ferrous iron in the coals, were studied by ESR techniques. The ESR spectra clearly demonstrated the presence of at least two types of carbon-centered free radical species, which might respectively attribute to the macromolecular phase and the molecular phase of coal. Grinding produced free radicals in coals. Exposure of freshly ground coal to air for 28 h induced a slight increase of free radicals for most of the coals, and a slight decrease after 4 months' exposure. The lung tissue samples of coal workers deceased of CWP showed similar ESR spectra as coal samples, and these radicals were highly stable in the lung. After incubation of coals with glutathione, hydrogen peroxide, sodium formate or oxygen, the coal sample from the Gardanne mine which has never induced CWP, and thus is the least hazardous coal, showed the most significant change in the carbon-centered free radical concentration. No significant changes were observed among other coals reported to induce CWP. On the other hand, we found that the coals released different amounts of Fe2+in an acidic medium. Interestingly, the prevalence of CWP correlates positively with the released Fe2+content in these coals and with the amount of oxygen radicals produced by the interaction of Fe2+with O2in the acidified coal filtrates. Our studies indicate that the carbon-centered free radicals may not be biologically relevant to coal dust-induced pneumoconiosis, whereas the acid soluble Fe2+, which may be dissolved in the phagolysosomes of macrophages, can then lead to Fe2+-induced oxidative stress and eventual CWP development.