GSI Helmholtzzentrum für Schwerionenforschung, Biophysics Department, Planckstraße 1, 64291 Darmstadt, Germany.
TIFPA, Trento Institute for Fundamentals Physics and Applications, Istituto Nazionale Fisica Nucleare, Via Sommarive 14-38123 Povo, TN, Italy.
Int J Mol Sci. 2019 Jan 16;20(2):352. doi: 10.3390/ijms20020352.
Hibernation has been proposed as a tool for human space travel. In recent years, a procedure to induce a metabolic state known as "synthetic torpor" in non-hibernating mammals was successfully developed. Synthetic torpor may not only be an efficient method to spare resources and reduce psychological problems in long-term exploratory-class missions, but may also represent a countermeasure against cosmic rays. Here we show the preliminary results from an experiment in rats exposed to ionizing radiation in normothermic conditions or synthetic torpor. Animals were irradiated with 3 Gy X-rays and organs were collected 4 h after exposure. Histological analysis of liver and testicle showed a reduced toxicity in animals irradiated in torpor compared to controls irradiated at normal temperature and metabolic activity. The expression of ataxia telangiectasia mutated (ATM) in the liver was significantly downregulated in the group of animal in synthetic torpor. In the testicle, more genes involved in the DNA damage signaling were downregulated during synthetic torpor. These data show for the first time that synthetic torpor is a radioprotector in non-hibernators, similarly to natural torpor in hibernating animals. Synthetic torpor can be an effective strategy to protect humans during long term space exploration of the solar system.
休眠状态被提议作为人类太空旅行的一种工具。近年来，一种在非冬眠哺乳动物中诱导称为“人工冬眠”的代谢状态的程序已成功开发。人工冬眠不仅可能是在长期探索性任务中节约资源和减少心理问题的有效方法，而且可能也是对抗宇宙射线的一种对策。在这里，我们展示了在正常体温或人工冬眠条件下暴露于电离辐射的大鼠实验的初步结果。用 3 Gy X 射线照射动物，并在照射后 4 小时收集器官。肝脏和睾丸的组织学分析显示，与在正常体温和代谢活性下照射的对照组相比，在冬眠中照射的动物的毒性降低。在肝脏中，共济失调毛细血管扩张突变（ATM）的表达在人工冬眠组中明显下调。在睾丸中，在人工冬眠期间，更多参与 DNA 损伤信号的基因下调。这些数据首次表明，人工冬眠是一种非冬眠动物的放射保护剂，类似于冬眠动物的自然冬眠。人工冬眠可能是保护人类在太阳系进行长期太空探索的有效策略。
