Low-Dose-Rate Irradiation for 1 Hour Induces Protection Against Lethal Radiation Doses but Does Not Affect Life Span of DBA/2 Mice

Prior findings showed that serum from DBA/2 mice that had been given whole-body irradiation for 1 hour at a low dose rate (LDR) of 30 cGy/h induced protection against radiation in reporter cells by a mechanism depending on transforming growth factor β3 and inducible nitric oxide synthase activity. In the present study, the effect of the 1 hour of LDR irradiation on the response of the preirradiated mice to a subsequent lethal dose and on the life span is examined. These DBA/2 mice were prime irradiated for 1 hour at 30 cGy/h. Two experiments with 9 and 9.5 Gy challenge doses given 6 weeks after priming showed increased survival in primed mice compared to unprimed mice followed up to 225 and 81 days after challenge irradiation, respectively. There was no overall significant difference in life span between primed and unprimed mice when no challenge irradiation was given. The males seemed to have a slight increase in lifespan after priming while the opposite was seen for the females.

[1]  P. Ebbesen,et al.  TGF-B3 Dependent Modification of Radiosensitivity in Reporter Cells Exposed to Serum From Whole-Body Low Dose-Rate Irradiated Mice , 2015, Dose-response : a publication of International Hormesis Society.

[2]  J. Sandvik,et al.  The roles of TGF-β3 and peroxynitrite in removal of hyper-radiosensitivity by priming irradiation , 2014, International journal of radiation biology.

[3]  J. Sandvik,et al.  The role of nitric oxide radicals in removal of hyper-radiosensitivity by priming irradiation , 2013, Journal of radiation research.

[4]  J. Magae,et al.  Prolongation of Life Span in the Accelerated Aging klotho Mouse Model, by Low-Dose-Rate Continuous γ Irradiation , 2013, Radiation research.

[5]  H. Kim,et al.  Life Span and Thymic Lymphoma Incidence in High- and Low-Dose-Rate Irradiated AKR/J Mice and Commonly Expressed Genes , 2010, Radiation research.

[6]  T. Stokke,et al.  Mechanisms of the elimination of low dose hyper-radiosensitivity in T-47D cells by low dose-rate priming , 2009, International journal of radiation biology.

[7]  G. Gasset,et al.  Effect of Continuous Irradiation with a Very Low Dose of Gamma Rays on Life Span and the Immune System in SJL Mice Prone to B-Cell Lymphoma , 2007, Radiation research.

[8]  T. Stokke,et al.  Recovery of low-dose hyper-radiosensitivity following a small priming dose depends on priming dose-rate , 2007 .

[9]  J. Schwartz.  Variability: the common factor linking low dose-induced genomic instability, adaptation and bystander effects. , 2007, Mutation research.

[10]  S. Tapio,et al.  Radioadaptive response revisited , 2007, Radiation and environmental biophysics.

[11]  T. Nomura,et al.  Enhancement of Bio-Protective Functions by Low Dose/Dose-Rate Radiation , 2006, Dose-response : a publication of International Hormesis Society.

[12]  K. Sakai,et al.  Further Study of Prolongation of Life Span Associated with Immunological Modification by Chronic Low-Dose-Rate Irradiation in MRL-lpr/lpr Mice: Effects of Whole-Life Irradiation , 2005, Radiation research.

[13]  Tsuneya Matsumoto,et al.  No Lengthening of Life Span in Mice Continuously Exposed to Gamma Rays at Very Low Dose Rates , 2003, Radiation research.

[14]  R. Schmidt-Ullrich,et al.  Stress and Radiation-Induced Activation of Multiple Intracellular Signaling Pathways1 , 2003, Radiation research.

[15]  Shu-zheng Liu.  On Radiation Hormesis Expressed in the Immune System , 2003, Critical reviews in toxicology.

[16]  G. Gasset,et al.  Life span, cancer and non-cancer diseases in mouse exposed to a continuous very low dose of γ-irradiation. , 2002, International journal of radiation biology.

[17]  Mark A. Suckow,et al.  The laboratory mouse , 2000 .

[18]  D. Boreham,et al.  The adaptive response modifies latency for radiation-induced myeloid leukemia in CBA/H mice. , 1999, Radiation research.

[19]  H. Planel,et al.  Effect of a Continuous Gamma Irradiation at a Very Low Dose on the Life Span of Mice , 1998, Gerontology.

[20]  M. Yonezawa,et al.  Two types of X-ray-induced radioresistance in mice: presence of 4 dose ranges with distinct biological effects. , 1996, Mutation research.

[21]  A. Wambersie,et al.  Survival and diseases in C57BL mice exposed to X rays or 3.1 MeV neutrons at an age of 7 or 21 days. , 1996, Radiation research.

[22]  J. F. Thomson,et al.  Life shortening in mice exposed to fission neutrons and gamma rays. VIII. Exposures to continuous gamma radiation. , 1989, Radiation research.

[23]  S. Wolff,et al.  Characterization of the adaptive response to ionizing radiation induced by low doses of X rays to human lymphocytes. , 1987, Radiation research.

[24]  F. S. Williamson,et al.  Life shortening in mice exposed to fission neutrons and gamma rays. V. Further studies with single low doses. , 1985, Radiation research.

[25]  R. Mole.  The LD50 for uniform low LET irradiation of man. , 1984, The British journal of radiology.

[26]  S. Wolff,et al.  Adaptive response of human lymphocytes to low concentrations of radioactive thymidine. , 1984, Science.

[27]  L. D. Carlson,et al.  EFFECTS OF PROLONGED LOW-LEVEL IRRADIATION OF MICE. , 1965, Radiation research.

[28]  C. Congdon,et al.  Long-term effects of acute and chronic irradiation in mice. I. Survival and tumor incidence following chronic irradiation of 0.11 r per day. , 1955, Journal of the National Cancer Institute.

[29]  J. Valentin.  The 2007 Recommendations of the International Commission on Radiological Protection. ICRP publication 103. , 2007, Annals of the ICRP.

[30]  M. Anver,et al.  CHAPTER 21 – Gerontology , 2004 .