Advanced Molecular Imaging Center, School of Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu city, Oita, Japan.
Free Radic Res. 2013 Jul;47(6-7):474-9. doi: 10.3109/10715762.2013.791025. Epub 2013 May 3.
Here, we focused on suppressive effect of ascorbic acid (AsA) on changes in mitochondrial function and mutagenesis by the radiation- induced bystander effect (RIBE). In mammalian cell lines, medium transfer assay was performed and conditioned medium including secreted factors after X-irradiation were examined to detect the RIBE. We found that the membrane potential and increased levels of superoxide radical (O2(-)) in mitochondria were modulated in cells treated with conditioned medium from irradiated cells. The result of the present study also demonstrated that increases in reactive oxygen species (ROS) levels led to the induction of gene mutations. Interestingly, the modulations in mitochondria, in addition to mutation inductions by RIBE, were completely suppressed by treatment with AsA in cells treated with conditioned medium. These results suggest that mutagenesis, which may have resulted from secreted factors involving the RIBE, may be induced by ROS that are localized in mitochondria and may be relieved by AsA.
在这里，我们专注于抗坏血酸 (AsA) 对辐射诱导的旁效应 (RIBE) 引起的线粒体功能变化和诱变的抑制作用。在哺乳动物细胞系中，进行了培养基转移实验，并检查了 X 射线照射后包含分泌因子的条件培养基，以检测 RIBE。我们发现，用辐照细胞的条件培养基处理的细胞中，线粒体的膜电位和超氧自由基 (O2(-)) 水平增加。本研究的结果还表明，活性氧 (ROS) 水平的增加导致基因突变的诱导。有趣的是，除了 RIBE 引起的突变诱导外，在用条件培养基处理的细胞中，用 AsA 处理完全抑制了线粒体的调节。这些结果表明，可能由涉及 RIBE 的分泌因子引起的突变诱导，可能是由位于线粒体中的 ROS 引起的，并且可以通过 AsA 缓解。
