Laboratoire de Physiologie Intégrative, Cellulaire et Moléculaire, CNRS, Université Lyon 1, Université de Lyon, 43 Bvd 11 Novembre 1918, 69622, Villeurbanne Cedex, France.
J Comp Physiol B. 2010 Feb;180(2):239-46. doi: 10.1007/s00360-009-0409-6. Epub 2009 Oct 9.
At hatching, breaking eggshell induces a surge in oxygen availability that is likely to generate oxidative stress in newborn chicks. To investigate the involvement of potential adaptive antioxidant mechanisms, we explored some markers of oxidative stress and the regulation of muscle avian uncoupling protein (avUCP) and adenine nucleotide translocase (ANT) in ducklings in the peri-hatching period. When compared with pre-hatching levels, the amount of peroxidized lipids were increased 24 h after external pipping in gastrocnemius muscle (+37%) and heart (+39%) as well as the muscle avUCP mRNA expression (+60%) but the susceptibility of red blood cells to free radicals (a functional test of oxidative status) was not affected. In order to relate these changes to the oxidative transition of hatching, an imposed hypoxia/re-oxygenation protocol was used. Hatched chicks that had spent the last 24 h of incubation in artificial severe hypoxia showed a rise in muscle (+50%) and heart (+69%) lipid peroxidation, an increased susceptibility of red blood cells to free radicals, a marked over-expression of avUCP mRNA (+105%) and a rise in mitochondrial ANT content (+54%). These results suggest that avian UCP and ANT may contribute to prepare incubating eggs to the oxidative stress generated by the hypoxia/re-oxygenation transition naturally occurring at hatching.
在孵化时，打破蛋壳会导致氧气供应激增，这很可能会导致新生小鸡产生氧化应激。为了研究潜在的适应性抗氧化机制，我们在孵化期间研究了鸭雏的一些氧化应激标志物以及肌肉禽类解偶联蛋白 (avUCP) 和腺嘌呤核苷酸转运蛋白 (ANT) 的调节。与孵化前的水平相比，在肌胃和心脏中，外部破壳后 24 小时过氧化脂质的含量增加了（分别增加了 37%和 39%），肌肉 avUCP mRNA 表达增加了（增加了 60%），但红细胞对自由基的敏感性（氧化状态的功能测试）没有受到影响。为了将这些变化与孵化的氧化转变联系起来，我们使用了强制缺氧/复氧方案。在人工严重缺氧中度过孵化最后 24 小时的孵出小鸡显示肌肉（增加 50%）和心脏（增加 69%）脂质过氧化增加，红细胞对自由基的敏感性增加，avUCP mRNA 的显著过表达（增加 105%）和线粒体 ANT 含量增加（增加 54%）。这些结果表明，禽类 UCP 和 ANT 可能有助于为孵化过程中自然发生的缺氧/复氧过渡所产生的氧化应激做好准备。
