Khan Mohammad A K, Wang Feiyue
Department of Chemistry, University of Manitoba, Winnipeg MB R3T 2N2, Canada.
Environ Toxicol Chem. 2009 Aug;28(8):1567-77. doi: 10.1897/08-375.1. Epub 2009 Apr 17.
The interaction between mercury (Hg) and selenium (Se) is one of the best known examples of biological antagonism, yet the underlying mechanism remains unclear. This review focuses on the possible pathways leading to the Hg-Se antagonism, with an emphasis on the potential Hg-Se compounds that are responsible for the antagonism at the molecular level (i.e., bis[methylmercuric]selenide, methylmercury selenocysteinate, selenoprotein P-bound HgSe clusters, and the biominerals HgSe(x)S(1-x)). The presence of these compounds in biological systems has been suggested by direct or indirect evidence, and their chemical properties support their potentially key roles in alleviating the toxicity of Hg and Se (at high Hg and Se exposures, respectively) and deficiency of Se (at low Se exposures). Direct analytical evidences are needed, however, to confirm their in vivo presence and metabolic pathways, as well as to identify the roles of other potential Hg-Se compounds. Further studies are also warranted for the determination of thermodynamic properties of these compounds under physiological conditions toward a better understanding of the Hg-Se antagonism in biota, particularly under real world exposure scenarios.
汞（Hg）与硒（Se）之间的相互作用是生物拮抗作用最广为人知的例子之一，但其潜在机制仍不清楚。本综述重点关注导致汞 - 硒拮抗作用的可能途径，特别强调在分子水平上导致拮抗作用的潜在汞 - 硒化合物（即双[甲基汞]硒化物、甲基汞硒代半胱氨酸、硒蛋白P结合的HgSe簇以及生物矿物HgSe(x)S(1-x)）。直接或间接证据表明这些化合物存在于生物系统中，并且它们的化学性质支持它们在减轻汞（分别在高汞暴露时）和硒（分别在高硒暴露时）的毒性以及硒缺乏（在低硒暴露时）方面可能发挥的关键作用。然而，需要直接分析证据来确认它们在体内的存在和代谢途径，以及确定其他潜在汞 - 硒化合物的作用。为了更好地理解生物群中的汞 - 硒拮抗作用，特别是在实际暴露场景下，还需要进一步研究来确定这些化合物在生理条件下的热力学性质。
