Protective Effects of Melatonin Against Low- and High-LET Irradiation
-
- ZHOU Guangming
- Radiobiology Group, Institute of Modern Physics, Chinese Academy of Sciences
-
- KAWATA Tetsuya
- Department of Radiology, Chiba University
-
- FURUSAWA Yoshiya
- Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences
-
- AOKI Mizuho
- Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences
-
- HIRAYAMA Ryoichi
- Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences
-
- ANDO Koichi
- Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences
-
- ITO Hisao
- Department of Radiology, Chiba University
Search this article
Abstract
To investigate the protective effects of melatonin against high-LET ionizing radiation, V79 Chinese hamster cells were irradiated with 100 keV/μm carbon beam. Parallel experiments were performed with 200 kV X-rays. To avoid the impact from extra solvents, melatonin was dissolved directly in culture medium. Cells were cultured in melatonin medium for 1 hr before irradiation. Cell inactivation was measured with conventional colony forming assay, medium containing 6-thioguanine was used for the selection of mutants at hprt locus, and the cell cycle was monitored by flow cytometry. Both carbon beam and X-rays induced cell inactivation, hprt gene mutation and cell cycle G2 block dose-dependently. But carbon beam showed stronger effects as indicated by all three endpoints and the relative biological effectiveness (RBE) was 3.5 for cell killing (at 10% survival level) and 2.9 for mutation induction (at 5 × 10-5 mutants/cell level). Melatonin showed protective effects against ionizing radiation in a dose-dependent manner. In terms of cell killing, melatonin only increased the survival level of those samples exposed to 8Gy or larger of X-rays or 6 Gy or larger of carbon beam. In the induction of hprt mutation and G2 block, melatonin reduced such effects induced by carbon beam but not by X-rays. The results suggest that melatonin reduces the direct interaction of particles with cells rather than an indirect interaction. Further studies are required to disclose the underlying mechanisms.<br>
Journal
-
- Journal of Radiation Research
-
Journal of Radiation Research 47 (2), 175-181, 2006
Journal of Radiation Research Editorial Committee
- Tweet
Keywords
Details 詳細情報について
-
- CRID
- 1390001205217779584
-
- NII Article ID
- 110004740245
-
- NII Book ID
- AA00705792
-
- ISSN
- 13499157
- 04493060
-
- NDL BIB ID
- 7960335
-
- Text Lang
- en
-
- Data Source
-
- JaLC
- NDL
- Crossref
- NDL-Digital
- CiNii Articles
-
- Abstract License Flag
- Disallowed