Kennedy Ann R, Ware Jeffrey H, Guan Jun, Donahue Jeremiah J, Biaglow John E, Zhou Zhaozong, Stewart Jelena, Vazquez Marcelo, Wan X Steven
Department of Radiation Oncology, University of Pennsylvania School of Medicine, 195 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA, USA.
Free Radic Biol Med. 2004 Jan 15;36(2):259-66. doi: 10.1016/j.freeradbiomed.2003.10.010.
Ionizing radiation-induced adverse biological effects impose serious challenges to astronauts during extended space travel. Of particular concern is the radiation from highly energetic, heavy, charged particles known as HZE particles. The objective of the present study was to characterize HZE particle radiation-induced adverse biological effects and evaluate the effect of D-selenomethionine (SeM) on the HZE particle radiation-induced adverse biological effects. The results showed that HZE particle radiation can increase oxidative stress, cytotoxicity, and cell transformation in vitro, and decrease the total antioxidant status in irradiated Sprague-Dawley rats. These adverse biological effects were all preventable by treatment with SeM, suggesting that SeM is potentially useful as a countermeasure against space radiation-induced adverse effects. Treatment with SeM was shown to enhance ATR and CHK2 gene expression in cultured human thyroid epithelial cells. As ionizing radiation is known to result in DNA damage and both ATR and CHK2 gene products are involved in DNA damage, it is possible that SeM may prevent HZE particle radiation-induced adverse biological effects by enhancing the DNA repair machinery in irradiated cells.
在长时间太空旅行中，电离辐射引起的不良生物学效应给宇航员带来了严峻挑战。特别值得关注的是来自高能重带电粒子（称为HZE粒子）的辐射。本研究的目的是表征HZE粒子辐射引起的不良生物学效应，并评估D-硒代蛋氨酸（SeM）对HZE粒子辐射引起的不良生物学效应的影响。结果表明，HZE粒子辐射可在体外增加氧化应激、细胞毒性和细胞转化，并降低受辐照的Sprague-Dawley大鼠的总抗氧化状态。这些不良生物学效应均可通过SeM治疗预防，表明SeM可能作为对抗太空辐射引起的不良影响的一种对策。已证明SeM处理可增强培养的人甲状腺上皮细胞中ATR和CHK2基因的表达。由于已知电离辐射会导致DNA损伤，且ATR和CHK2基因产物均参与DNA损伤，因此SeM有可能通过增强受辐照细胞中的DNA修复机制来预防HZE粒子辐射引起的不良生物学效应。
