{sub p}53-Dependent Adaptive Responses in Human Cells Exposed to Space Radiations

Journal Article · Mon Nov 15 00:00:00 EST 2010 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2010.04.062· OSTI ID:21451164

Takahashi, Akihisa ^[1]; Xiaoming, Su ^[1]; Suzuki, Hiromi ^[2]; Omori, Katsunori ^[3]; Seki, Masaya; Hashizume, Toko ^[4]; Shimazu, Toru ^[2]; Ishioka, Noriaki ^[3]; Iwasaki, Toshiyasu ^[5]; Ohnishi, Takeo ^[6]

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1. Department of Biology, School of Medicine, Nara Medical University, Nara (Japan)
2. Japan Space Forum, Tokyo (Japan)
3. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Ibaraki (Japan)
4. Space Environmental Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima (Japan)
5. Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of the Electric Power Industry of Japan, Tokyo (Japan)
6. Department of Radiation Oncology, School of Medicine, Nara Medical University, Nara (Japan)

Purpose: It has been reported that priming irradiation or conditioning irradiation with a low dose of X-rays in the range of 0.02-0.1 Gy induces a p53-dependent adaptive response in mammalian cells. The aim of the present study was to clarify the effect of space radiations on the adaptive response. Methods and Materials: Two human lymphoblastoid cell lines were used; one cell line bears a wild-type p53 (wtp53) gene, and another cell line bears a mutated p53 (mp53) gene. The cells were frozen during transportation on the space shuttle and while in orbit in the International Space Station freezer for 133 days between November 15, 2008 and March 29, 2009. After the frozen samples were returned to Earth, the cells were cultured for 6 h and then exposed to a challenging X-ray-irradiation (2 Gy). Cellular sensitivity, apoptosis, and chromosome aberrations were scored using dye-exclusion assays, Hoechst33342 staining assays, and chromosomal banding techniques, respectively. Results: In cells exposed to space radiations, adaptive responses such as the induction of radioresistance and the depression of radiation-induced apoptosis and chromosome aberrations were observed in wtp53 cells but not in mp53 cells. Conclusion: These results have confirmed the hypothesis that p53-dependent adaptive responses are apparently induced by space radiations within a specific range of low doses. The cells exhibited this effect owing to space radiations exposure, even though the doses in space were very low.

• OSTI ID: 21451164
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 78, Issue 4; Other Information: DOI: 10.1016/j.ijrobp.2010.04.062; PII: S0360-3016(10)00676-0; Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS
ANIMAL CELLS
APOPTOSIS
CHROMOSOMAL ABERRATIONS
GENES
INTERNATIONAL SPACE STATION
RADIOSENSITIVITY
SPACE SHUTTLES
X RADIATION
AIRCRAFT
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
MUTATIONS
RADIATIONS
SATELLITES
SENSITIVITY
SPACE VEHICLES
VEHICLES