Cabañero Ana I, Madrid Yolanda, Cámara Carmen
Departamento de Química Analítica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
J Agric Food Chem. 2006 Jun 14;54(12):4461-8. doi: 10.1021/jf0603230.
An in vivo experiment was conducted to assess selenium bioaccumulation and bioaccessibility through the food chain and its effect on Hg toxicity. For this purpose 72 chickens were fed under different controlled conditions. Chickens were exposed to a common basal diet or a diet supplemented with Hg(II), MeHg, and Se(IV). Enzymatic digestion (feed, chicken muscle, liver, and kidney) as well as simulated human gastric and intestinal digestion (chicken muscle) led to the identification of selenomethionine (SeMet) in all the samples analyzed. Therefore, although chickens have no efficient mechanism for SeMet synthesis they can be considered as a source of SeMet due to its diet and the plant-animal food chain. The kidneys were the target organ for both total Se and SeMet in chickens (1604 +/- 136 and 128 +/- 6 microg kg(-1), respectively), but the greatest body store, among the tissues studied, was the muscle in both cases (84-96% of total Se). Long-term administration of inorganic and organic mercury did not alter SeMet distribution significantly. The antagonistic effect of Se on Hg toxicity by favoring MeHg demethylation is discussed.
进行了一项体内实验，以评估硒通过食物链的生物累积和生物可及性及其对汞毒性的影响。为此，在不同的受控条件下饲养了72只鸡。鸡被喂食普通基础饲料或添加了Hg(II)、甲基汞和Se(IV)的饲料。酶消化（饲料、鸡肉、肝脏和肾脏）以及模拟人体胃和肠道消化（鸡肉）导致在所有分析的样品中均鉴定出硒代蛋氨酸（SeMet）。因此，尽管鸡没有合成SeMet的有效机制，但由于其饮食和植物-动物食物链，它们可被视为SeMet的来源。肾脏是鸡体内总硒和SeMet的靶器官（分别为1604±136和128±6μg kg(-1)），但在所研究的组织中，两种情况下最大的身体储存部位都是肌肉（占总硒的84-96%）。长期施用无机汞和有机汞并未显著改变SeMet的分布。讨论了硒通过促进甲基汞去甲基化对汞毒性的拮抗作用。
