Opportunities for nutritional amelioration of radiation-induced cellular damage.
Opportunities for nutritional amelioration of radiation-induced cellular damage.
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DOI：
10.1016/s0899-9007(02)00945-0
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发表时间：
2002-10
期刊：
影响因子：
4.4
通讯作者：
N. Turner;L. Braby;J. Ford;J. Lupton
中科院分区：
文献类型：
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作者：
N. Turner;L. Braby;J. Ford;J. Lupton
空间飞行固有的封闭环境和有限的规避能力使宇航员暴露于许多潜在的有害物质（环境中的化学污染物和宇宙辐射暴露）。目前用于实现太空飞行的电力系统过于昂贵，无法满足完全保护宇航员免受宇宙辐射的重量要求。因此，辐射对宇航员来说是一个重大的、目前无法解决的风险，尤其是对长时间的太空飞行来说。长期太空飞行主要关注的有害辐射影响是对眼球晶状体的损害、对免疫系统的损害、对中枢神经系统的损害和癌症。除了对细胞中生物分子的直接损伤外，辐射暴露还会引起氧化损伤。许多天然抗氧化剂，无论是在受辐射之前还是之后服用，都能够提供一定程度的辐射防护。除了从维生素E、维生素C和叶酸等众所周知的抗氧化剂中获得有益效果外，最近发现的几种抗氧化剂分子，如类黄酮、表没食子儿茶素和其他多酚类物质，也能起到一定的保护作用。考虑到ω-3多不饱和脂肪酸被认为容易过氧化，含有高水平ω-3多不饱和脂肪酸的饮食提供的保护有些违反直觉。即使我们掌握了这些信息，也很难预测哪种饮食调整能最好地降低宇航员、生活在地球上的人、或那些忍受诊断性或治疗性辐射暴露的人受到辐射的风险。在我们能够提出具体建议之前，必须在人类身上做更多的工作，无论是在地球上，还是最好在太空中。
The closed environment and limited evasive capabilities inherent in space flight cause astronauts to be exposed to many potential harmful agents (chemical contaminants in the environment and cosmic radiation exposure). Current power systems used to achieve space flight are prohibitively expensive for supporting the weight requirements to fully shield astronauts from cosmic radiation. Therefore, radiation poses a major, currently unresolvable risk for astronauts, especially for long-duration space flights. The major detrimental radiation effects that are of primary concern for long-duration space flights are damage to the lens of the eye, damage to the immune system, damage to the central nervous system, and cancer. In addition to the direct damage to biological molecules in cells, radiation exposure induces oxidative damage. Many natural antioxidants, whether consumed before or after radiation exposure, are able to confer some level of radioprotection. In addition to achieving beneficial effects from long-known antioxidants such as vitamins E and C and folic acid, some protection is conferred by several recently discovered antioxidant molecules, such as flavonoids, epigallocatechin, and other polyphenols. Somewhat counterintuitive is the protection provided by diets containing elevated levels of ω-3 polyunsaturated fatty acids, considering they are thought to be prone to peroxidation. Even with the information we have at our disposal, it will be difficult to predict the types of dietary modifications that can best reduce the risk of radiation exposure to astronauts, those living on Earth, or those enduring diagnostic or therapeutic radiation exposure. Much more work must be done in humans, whether on Earth or, preferably, in space, before we are able to make concrete recommendations.