Lifetime and trans-generational epigenetic impacts of early-life radiation in a model insect, Acheta domesticus: Modulation by radioprotective and methylation-enhancing diets

受环境辐射影响的动物物种中约90%是昆虫。蟋蟀发育迅速，寿命短，是评估辐射的终生影响和代际影响的理想工具。青少年和成年人吃同样的食物，所以保护性饮食可以在短短几个月内在整个生命周期中进行测试。基因决定了动物的发育和功能。一个被称为“DNA甲基化”的过程决定了某些基因是被激活还是被关闭，辐射暴露可以永久改变DNA甲基化。因此，在生命早期的一次辐射暴露可以通过改变基因的开/关状态来改变动物的形式和功能。这些变化可能对生物体有益或有害。“杀不死你的东西会让你变得更强”这一观点适用于辐射和一门被称为“毒物兴奋效应”的科学。“高剂量的辐射是有害的，但小剂量的辐射实际上是有益的。我们想探索哪些辐射剂量会在蟋蟀的整个生命周期和下一代产生后续的益处或危害（例如，生长、繁殖、衰老率和抗应激性）。我们特别感兴趣的是，了解生命早期的辐射暴露是否可以改善对随后辐射的保护。我们还想知道早期放射治疗是否可以预防其他类型的压力。我们想知道DNA甲基化是如何促成这一点的，以及对辐射的抵抗力是否可以传递给下一代。我们还设计了两种膳食补充剂，应该具有辐射防护品质。我们将测试这些饮食是否能减少与高剂量辐射相关的损害。我们还希望研究这些饮食是否可以加强低剂量辐射对晚年和下一代的益处。这些发现将适用于对核电工业有用的辐射生物学的各个方面，并与辐射污染的环境影响有关。如果这些饮食可以保护免受辐射损伤，那么它们可能对宇航员，核工业工人或意外暴露于辐射的人有益。

About 90% of animal species impacted by environmental radiation exposure are insects. Rapid development and short lives make crickets ideal for assessing lifetime and trans-generational impacts of radiation. Juveniles and adults eat the same food so protective diets can be tested across the entire lifetime in just a few months. Genes determine how animals develop and function. A process called "DNA methylation" determines whether certain genes are activated or shut off, and radiation exposure can permanently alter DNA methylation. Consequently, a single exposure to radiation in early life can change the form and function of animals via altering the on/off status of genes. These changes can be either beneficial or harmful to the organism. The idea that "what does not kill you makes you stronger" applies to radiation and an entire science called "hormesis." High doses of radiation are harmful, but small doses of radiation can actually be beneficial. We want to explore which radiation doses yield subsequent benefits or harm across the lifespan and the next generation of crickets (e.g., growth, reproduction, aging rates, and resistance to stress). We are particularly interested in knowing whether radiation exposure early in life can improve protection against subsequent irradiation. We also want to know if early radiation can protect against other types of stress. We seek to know how DNA methylation may contribute to this, and whether resistance to radiation can be passed on to the next generation. We also designed two dietary supplements that should have radio-protective qualities. We will test whether these diets reduce damage associated with high-dose radiation. We also wish to examine whether these diets may strengthen the benefits of low-dose radiation in later life and in the next-generation. These findings would apply to diverse aspects of radiation biology useful to the nuclear power industry and relevant to environmental impacts of radiation contamination. If the diets are protective against radiation damage they may be of benefit to astronauts, nuclear industry workers or those accidentally exposed to radiation.