The Chemical Nature of Mercury in Human Brain Following Poisoning or Environmental Exposure
The Chemical Nature of Mercury in Human Brain Following Poisoning or Environmental Exposure
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DOI：
10.1021/cn1000765
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发表时间：
2010-12-01
影响因子：
5
通讯作者：
George, Graham N.
中科院分区：
文献类型：
--
作者：
Korbas, Malgorzata;O'Donoghue, John L.;George, Graham N.
甲基汞是人类接触到的最具潜在毒性的物质之一，无论是通过中毒接触到的高浓度甲基汞，还是通过食用鱼类和其他海产品接触到的低浓度甲基汞。然而，甲基汞对人体毒性的分子机制仍然知之甚少。我们使用同步辐射X射线吸收光谱（XAS）研究汞在人脑组织中的化学形态。高浓度甲基汞中毒的个体表现出皮质硒含量升高，其中硒化汞纳米颗粒以及一些无机汞和与有机硫结合的甲基汞的比例很大。终生大量食用鱼类的人硒化汞和半胱氨酸甲基汞的水平要低得多。汞暴露没有干扰有机硒水平。这些结果阐明了中枢神经系统中的关键解毒途径，并为生物监测的适当方法提供了新的见解。
Methylmercury is among the most potentially toxic species to which human populations are exposed, both at high levels through poisonings and at lower levels through consumption of fish and other seafood. However, the molecular mechanisms of methylmercury toxicity in humans remain poorly understood. We used synchrotron X-ray absorption spectroscopy (XAS) to study mercury chemical forms in human brain tissue. Individuals poisoned with high levels of methylmercury species showed elevated cortical selenium with significant proportions of nanoparticulate mercuric selenide plus some inorganic mercury and methylmercury bound to organic sulfur. Individuals with a lifetime of high fish consumption showed much lower levels of mercuric selenide and methylmercury cysteineate. Mercury exposure did not perturb organic selenium levels. These results elucidate a key detoxification pathway in the central nervous system and provide new insights into the appropriate methods for biological monitoring.