Department of Bioenvironmental Systems Engineering, National Taiwan University, 1 Roosevelt Road, Sec 4, Taipei 106, Taiwan.
Food Chem Toxicol. 2011 Apr;49(4):812-9. doi: 10.1016/j.fct.2010.12.002. Epub 2010 Dec 7.
Selenium is an essential trace nutrient that has a narrow exposure window between its beneficial and detrimental effects. We investigated how selenium affected the development, fertility, and cholinergic signaling of the nematode, Caenorhabditis elegans. Our results showed that selenite supplementation at 0.01 and 0.05 μM accelerated development and increased the brood size, while the addition of 20 μM selenite retarded the developmental rate and decreased the brood size. We also showed that the 0.01 μM selenite-pretreated nematodes were more resistant to paralysis induced by an acetylcholinesterase inhibitor, aldicarb, and a nicotinic acetylcholine receptor agonist, levamisole, compared to untreated worms. In contrast, 20 μM selenite-pretreated animals were more sensitive to aldicarb- and levamisole-induced paralysis compared to untreated worms. We measured the internal selenium in supplemented worms using inductively coupled plasma atomic emission spectroscopy, and the data obtained suggested that selenite added to growth medium was taken up by the worms. Taken together, these results suggest that selenite exerts both ameliorative and toxic effects on C.elegans, depending on the amount. Our investigations here thus reinforce our understanding of the ameliorative and toxic effects of selenium on development, reproduction, and cholinergic signaling.
硒是一种必需的痕量营养元素，其有益和有害影响之间的暴露窗口很窄。我们研究了硒如何影响线虫秀丽隐杆线虫的发育、生育能力和胆碱能信号传导。我们的结果表明，亚硒酸盐在 0.01 和 0.05 μM 时的补充加速了发育并增加了繁殖量，而 20 μM 亚硒酸盐的添加则延缓了发育速度并减少了繁殖量。我们还表明，与未处理的线虫相比，用 0.01 μM 亚硒酸盐预处理的线虫对乙酰胆碱酯酶抑制剂涕灭威和烟碱型乙酰胆碱受体激动剂左旋咪唑诱导的麻痹更具抗性。相比之下，与未处理的线虫相比，用 20 μM 亚硒酸盐预处理的动物对涕灭威和左旋咪唑诱导的麻痹更敏感。我们使用电感耦合等离子体原子发射光谱法测量了补充线虫中的内部硒，获得的数据表明，添加到生长培养基中的亚硒酸盐被线虫吸收。综上所述，这些结果表明，亚硒酸盐对 C.elegans 产生了既改善又有毒的影响，具体取决于剂量。我们在这里的研究进一步增强了我们对硒对发育、繁殖和胆碱能信号传导的改善和毒性作用的理解。
