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Calabrese EJ, Selby PB. Muller's genetic load/species extinction hypothesis. ENVIRONMENTAL RESEARCH 2024; 241:117599. [PMID: 37952856 DOI: 10.1016/j.envres.2023.117599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/14/2023]
Abstract
The genetic load hypothesis of Hermann Muller raised the profound question of possible species extinction, even for humans, following a prolonged accumulation of recessive genes due to ionizing radiation exposure within the population. Two major mouse radiation research teams in the United States provided the most extensive tests of Muller's hypothesis. One group continued its study for more than two decades, over 82 consecutive generations, approximating 2500 human years. Even though Muller had stressed for decades his fear of species-threatening effects, no significant effects were observed for related factors such as reproductive fitness and longevity. Yet, the paper presenting the data of the 82-generation negative study has only been cited five times in 45 years. Altogether numerous laboratories worldwide collected vast amounts of data on mice, rats, and swine in an unsuccessful attempt to see if there was convincing evidence to support the genetic load theory and claims that species might deteriorate or be rendered extinct. This paper re-examines Muller's genetic load hypothesis with a new evaluation of how that hypothesis was tested and the significance of the findings, with most of those studies being completed before the BEIR I Committee Report in 1972. That committee briefly discussed the available evidence, mostly ignoring those results as they proceeded to make hereditary risk estimates both for (1) the first generation after a radiation exposure and (2) for the time, in the distant future, when a hypothetical genetic equilibrium would be reached. Their estimates assumed accumulation of harmful mutations and a linear no-threshold dose response extending all of the way down to a single ionization. More recent data on induction by ionizing radiation of dominant mutations that affect the skeletons of mice provide further robust supporting evidence that the generationally cumulative and LNT-based assumptions underpinning Muller's genetic load hypothesis are not correct.
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Affiliation(s)
- Edward J Calabrese
- School of Public Health and Health Sciences, Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA, 01003, USA.
| | - Paul B Selby
- Retired from Oak Ridge National Laboratory at Oak Ridge, TN; Home Address: 4088 Nottinghill Gate Road, Upper Arlington, OH, 43220, USA.
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Selby PB, Calabrese EJ. How self-interest and deception led to the adoption of the linear non-threshold dose response (LNT) model for cancer risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:165402. [PMID: 37454843 DOI: 10.1016/j.scitotenv.2023.165402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/06/2023] [Accepted: 07/06/2023] [Indexed: 07/18/2023]
Abstract
This paper clarifies scientific contributions and deceptive/self-serving decisions of William L. Russell and Liane Russell that led to the adoption of the linear non-threshold (LNT) model for cancer risk assessment by the US EPA. By deliberately failing to report an extremely large cluster of mutations in the control group of their first experiment, and thereby greatly suppressing its mutation rate, the Russells incorrectly claimed that the male mouse was 15-fold more susceptible to ionizing-radiation-induced gene mutations as compared with fruit flies. This self-serving error not only propelled their research program into one of great prominence, but it also promoted the LNT-based doubling dose (DD) concept in radiation genetics/cancer risk assessment, by the US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel (1956). The DD concept became a central element in their recommendation that regulatory agencies switch from a threshold to an LNT model. This error occurred because of a decision by W. Russell not to report that a large cluster of control group mutations found in an experiment for which preliminary results were reported in 1951. This failure to report that cluster and similar clusters continued throughout the careers of the Russells, resulting in massive overestimation of low dose radiation risks supporting the LNT. The Russell database and the repeated claim that those data show that there is no threshold dose rate for mutation in irradiated mouse stem-cell spermatogonia, have provided mechanistic validation supporting the epidemiological LNT hypothesis for radiation-induced leukemias and cancers. This reanalysis supports the threshold model for both males and females, thereby rebutting epidemiological extrapolations from the NAS and EPA claiming support for the LNT hypothesis for cancer risk assessment. The implications of the Russell errors/deceptions, how/why they occurred, and their impact upon society are enormous and need to be addressed by scientific/regulatory agencies, affecting regulatory and litigation activities.
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Affiliation(s)
- Paul B Selby
- Retired from Oak Ridge National Laboratory at Oak Ridge, TN, Home Address: 4088 Nottinghill Gate Road, Upper Arlington, OH 43220, USA
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA 01003, USA.
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3
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Calabrese EJ, Agathokleous E, Giordano J, Selby PB. Manhattan Project genetic studies: Flawed research discredits LNT recommendations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 319:120902. [PMID: 36566922 DOI: 10.1016/j.envpol.2022.120902] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/28/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
This paper reexamines the technical report (∼ one page) of Uphoff and Stern (1949) in Science that was highly relied upon by the US National Academy of Sciences (NAS) Biological Effects of Atomic Radiation (BEAR) I Genetics Panel to support a linearity dose response for radiation risk assessment. The present paper demonstrates that research of Uphoff and Stern (1949) to evaluate whether total dose or dose rate best estimated radiation risks included two variables, thereby precluding the ability to accurately derive a reliable conclusion about this topic. Furthermore, the acute dose selected by Uphoff and Stern was given at a strikingly low dose rate that may have precluded the capacity to adequately test the total dose/dose rate hypothesis, even with a proper study design which also this research did not possess. The issue of total dose and dose rate was much later successfully addressed by Russell et al. (1958) using a murine model, yielding a dose-rate rather than a total dose conclusion. The failure to subject the experimental details of the Uphoff and Stern (1949) study to peer-review and publication in the open literature precluded a rigorous and necessary evaluation, profoundly and improperly impacting the adoption of the linear dose response model.
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Affiliation(s)
- Edward J Calabrese
- Department of Environmental Health Sciences; Morrill I, N344; University of Massachusetts, Amherst, MA, 01003, USA.
| | - Evgenios Agathokleous
- School of Applied Meteorology; Nanjing University of Information Science & Technology, Nanjing, 210044, China.
| | - James Giordano
- Departments of Neurology and Biochemistry, and Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington, DC, 20007, USA.
| | - Paul B Selby
- Retired from Oak Ridge National Laboratory at Oak Ridge, TN, USA; 4088 Nottinghill Gate Road; Upper Arlington, OH, 43220, USA.
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4
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Kawamura K, Suzuki K, Mitsutake N. Technical Report: A Simple and Robust Real-Time Quantitative PCR Method for the Detection of Radiation-Induced Multiple Exon Deletions of the Human HPRT Gene. Radiat Res 2023; 199:83-88. [PMID: 34143221 DOI: 10.1667/rade-21-00047.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/25/2021] [Indexed: 01/12/2023]
Abstract
The hypoxanthine-phosphoribosyltransferase (HPRT) mutation assay has been widely used to investigate gene mutations induced by radiation. Here, we developed a novel method detecting deletions of multiple exons of the HPRT gene based on real-time quantitative PCR (qPCR). Immortalized normal human fibroblasts (BJ1-hTERT) were irradiated at various doses with γ rays, subjected to the 6-thioguanine (6-TG) selection, and more than one hundred 6-TG-resistant (6-TGR) clones were isolated. High-molecular-weight genomic DNA was extracted, and real-time qPCR was performed with the nine exon-specific primers. Optimization of the primer concentration, appropriate selection of PCR enzyme and refinement of the reaction profiles enabled simultaneous quantitative amplification of each exon. We were able to identify 6-TGR clones with total deletions, which did not show any amplification of the nine exons, and partial deletion mutants, in which one or some of the nine exons were missing, within a few days. This novel technique allows systematic determination of multiple deletions of the HPRT exons induced by ionizing radiation, enabling high-throughput and robust analysis of multiple HPRT mutants.
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Affiliation(s)
- Kasumi Kawamura
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Keiji Suzuki
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Norisato Mitsutake
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
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Abstract
This paper represents the first assessment of agent-induced hormetic dose responses in induced pluripotent stem cells and their derived cells. The hormetic dose responses were induced by a broad range of chemicals, including pharmaceuticals (eg, metformin), dietary supplements/extracts from medicinal plants (eg, curcumin), and endogenous agents (eg, melatonin). The paper assesses the mechanistic foundations of these induced hormetic dose responses, their therapeutic implications and comparison with hormetic responses in multiple adult and embryonic stem cells.
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Affiliation(s)
- Edward J Calabrese
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA, USA
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6
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Buchumenski I, Roth SH, Kopel E, Katsman E, Feiglin A, Levanon EY, Eisenberg E. Global quantification exposes abundant low-level off-target activity by base editors. Genome Res 2021; 31:2354-2361. [PMID: 34667118 PMCID: PMC8647836 DOI: 10.1101/gr.275770.121] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 10/14/2021] [Indexed: 12/26/2022]
Abstract
Base editors are dedicated engineered deaminases that enable directed conversion of specific bases in the genome or transcriptome in a precise and efficient manner, and hold promise for correcting pathogenic mutations. A major concern limiting application of this powerful approach is the issue of off-target edits. Several recent studies have shown substantial off-target RNA activity induced by base editors and demonstrated that off-target mutations may be suppressed by improved deaminases versions or optimized guide RNAs. Here, we describe a new class of off-target events that are invisible to the established methods for detection of genomic variations and were thus far overlooked. We show that nonspecific, seemingly stochastic, off-target events affect a large number of sites throughout the genome or the transcriptome, and account for the majority of off-target activity. We develop and employ a different, complementary approach that is sensitive to the stochastic off-target activity and use it to quantify the abundant off-target RNA mutations due to current, optimized deaminase editors. We provide a computational tool to quantify global off-target activity, which can be used to optimize future base editors. Engineered base editors enable directed manipulation of the genome or transcriptome at single-base resolution. We believe that implementation of this computational approach would facilitate design of more specific base editors.
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Affiliation(s)
- Ilana Buchumenski
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Shalom Hillel Roth
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Eli Kopel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Efrat Katsman
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Ariel Feiglin
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Erez Y Levanon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
- The Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Eli Eisenberg
- Raymond and Beverly Sackler School of Physics and Astronomy and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 69978, Israel
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7
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Increased Frequency of Copy Number Variations Revealed by Array Comparative Genomic Hybridization in the Offspring of Male Mice Exposed to Low Dose-Rate Ionizing Radiation. Int J Mol Sci 2021; 22:ijms222212437. [PMID: 34830319 PMCID: PMC8621608 DOI: 10.3390/ijms222212437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/16/2021] [Accepted: 11/16/2021] [Indexed: 11/26/2022] Open
Abstract
There is very little information on the transgenerational or genetic effects of low dose-rate ionizing radiation. We report the detection of the transgenerational effects of chronic low dose-rate irradiation in mice, at the molecular level in the whole genome, using array comparative genomic hybridization technology. We observed that the number of the mice with de novo copy number variations (specifically, deletions) was significantly increased in the offspring of C57BL/6J male mice exposed to 20 mGy/day gamma-rays for 400 days (total dose: 8000 mGy), as compared to non-irradiated controls. We did not detect any difference in the size of the de novo deletions between the irradiated and the non-irradiated groups. An analysis of the life span of the offspring suggested a possibility that de novo copy-number variations may be associated with shorter life spans.
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Meier B, Volkova NV, Wang B, González-Huici V, Bertolini S, Campbell PJ, Gerstung M, Gartner A. C. elegans genome-wide analysis reveals DNA repair pathways that act cooperatively to preserve genome integrity upon ionizing radiation. PLoS One 2021; 16:e0258269. [PMID: 34614038 PMCID: PMC8494335 DOI: 10.1371/journal.pone.0258269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/22/2021] [Indexed: 11/22/2022] Open
Abstract
Ionizing radiation (IR) is widely used in cancer therapy and accidental or environmental exposure is a major concern. However, little is known about the genome-wide effects IR exerts on germ cells and the relative contribution of DNA repair pathways for mending IR-induced lesions. Here, using C. elegans as a model system and using primary sequencing data from our recent high-level overview of the mutagenic consequences of 11 genotoxic agents, we investigate in detail the genome-wide mutagenic consequences of exposing wild-type and 43 DNA repair and damage response defective C. elegans strains to a Caesium (Cs-137) source, emitting γ-rays. Cs-137 radiation induced single nucleotide variants (SNVs) at a rate of ~1 base substitution per 3 Gy, affecting all nucleotides equally. In nucleotide excision repair mutants, this frequency increased 2-fold concurrently with increased dinucleotide substitutions. As observed for DNA damage induced by bulky DNA adducts, small deletions were increased in translesion polymerase mutants, while base changes decreased. Structural variants (SVs) were augmented with dose, but did not arise with significantly higher frequency in any DNA repair mutants tested. Moreover, 6% of all mutations occurred in clusters, but clustering was not significantly altered in any DNA repair mutant background. Our data is relevant for better understanding how DNA repair pathways modulate IR-induced lesions.
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Affiliation(s)
- Bettina Meier
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, United Kingdom
| | - Nadezda V. Volkova
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, United Kingdom
| | - Bin Wang
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, United Kingdom
- National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Víctor González-Huici
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, United Kingdom
| | - Simone Bertolini
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, United Kingdom
| | - Peter J. Campbell
- Cancer, Ageing and Somatic Mutation, Wellcome Sanger Institute, Hinxton, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- Department of Haematology, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Moritz Gerstung
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, United Kingdom
- European Molecular Biology Laboratory, Genome Biology Unit, Heidelberg, Germany
| | - Anton Gartner
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, United Kingdom
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
- Department of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
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9
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Cornforth MN, Bedford JS, Bailey SM. Destabilizing Effects of Ionizing Radiation on Chromosomes: Sizing up the Damage. Cytogenet Genome Res 2021; 161:328-351. [PMID: 34488218 DOI: 10.1159/000516523] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 02/16/2021] [Indexed: 11/19/2022] Open
Abstract
For long-term survival and evolution, all organisms have depended on a delicate balance between processes involved in maintaining stability of their genomes and opposing processes that lead toward destabilization. At the level of mammalian somatic cells in renewal tissues, events or conditions that can tip this balance toward instability have attracted special interest in connection with carcinogenesis. Mutations affecting DNA (and its subsequent repair) would, of course, be a major consideration here. These may occur spontaneously through endogenous cellular processes or as a result of exposure to mutagenic environmental agents. It is in this context that we discuss the rather unique destabilizing effects of ionizing radiation (IR) in terms of its ability to cause large-scale structural rearrangements to the genome. We present arguments supporting the conclusion that these and other important effects of IR originate largely from microscopically visible chromosome aberrations.
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Affiliation(s)
- Michael N Cornforth
- Department of Radiation Oncology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Joel S Bedford
- Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Susan M Bailey
- Department of Environmental & Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
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10
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Bando M, Tsunoyama Y, Suzuki K, Toki H. WAM to SeeSaw model for cancer therapy - overcoming LQM difficulties. Int J Radiat Biol 2020; 97:228-239. [PMID: 33253050 DOI: 10.1080/09553002.2021.1854487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE The assessment of biological effects caused by radiation exposure has been currently carried out with the linear-quadratic (LQ) model as an extension of the linear non-threshold (LNT) model. In this study, we suggest a new mathematical model named as SeaSaw (SS) model, which describes proliferation and cell death effects by taking account of Bergonie-Tribondeau's law in terms of a differential equation in time. We show how this model overcomes the long-standing difficulties of the LQ model. MATERIALS AND METHODS We construct the SS model as an extended Wack-A-Mole (WAM) model by using a differential equation with respect to time in order to express the dynamics of the proliferation effect. A large number of accumulated data of such parameters as α and β in the LQ based models provide us with valuable pieces of information on the corresponding parameter b 1 and the maximum volume V m of the SS model. The dose rate b 1 and the notion of active cell can explain the present data without introduction of β, which is obtained by comparing the SS model with not only the cancer therapy data but also with in vitro experimental data. Numerical calculations are presented to grasp the global features of the SS model. RESULTS The SS model predicts the time dependence of the number of active- and inactive-cells. The SS model clarifies how the effect of radiation depends on the cancer stage at the starting time in the treatment. Further, the time dependence of the tumor volume is calculated by changing individual dose strength, which results in the change of the irradiation duration for the same effect. We can consider continuous irradiation in the SS model with interesting outcome on the time dependence of the tumor volume for various dose rates. Especially by choosing the value of the dose rate to be balanced with the total growth rate, the tumor volume is kept constant. CONCLUSIONS The SS model gives a simple equation to study the situation of clinical radiation therapy and risk estimation of radiation. The radiation parameter extracted from the cancer therapy is close to the value obtained from animal experiment in vitro and in vivo. We expect the SS model leads us to a unified description of radiation therapy and protection and provides a great development in cancer-therapy clinical-planning.
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Affiliation(s)
- Masako Bando
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
| | - Yuichi Tsunoyama
- Radioisotope Research Center, Agency for Health, Safety and Environment, Kyoto University, Kyoto, Japan
| | - Kazuyo Suzuki
- Preemptive Medicine and Lifestyle-Related Disease Research Center, Kyoto University Hospital, Kyoto University, Kyoto, Japan
| | - Hiroshi Toki
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
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11
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Vidal LM, Pimentel E, Cruces MP, Sánchez-Meza JC. Evaluating the effect of low dose rate of gamma rays in germ cells of Drosophila melanogaster. Int J Radiat Biol 2020; 96:1068-1075. [PMID: 32338555 DOI: 10.1080/09553002.2020.1761566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Purpose: Evaluation of genetic risk in germ cells is still matter of research, mainly due to their role in the transmission of genetic information from one generation to another. Although numerous experiments have been carried out in Drosophila in order to study the effect of radiation on germ cells, the role of dose rate (DR) has not been fully explored. The purpose of this study was to evaluate the action of DR on the radioprotection induction on male germ cell of D. melanogaster.Material and method: The productivity and the sex-linked recessive lethal (SLRL) tests were used to evaluate the radio-sensitivity of different states of the germ line of males. Two-day-old males of Canton-S wild type strain were pretreated with 0.2 Gy at 5.4 or 34.3 Gy/h of gamma rays from a 60Co source, three hours later, they were irradiated with 20 Gy at 907.7 Gy/h. Thereafter, each single male was crossed with 3 five-day old Basc virgin females, that were replaced every other day by new females. This procedure was conducted three times, to test the whole germ cell stages.Results: Females crossed with males irradiated with 0.2 Gy at both DR tested, laid a higher number of eggs than control, but egg-viability was reduced. On the other hand, in the group of 0.2 Gy + 20 Gy -combined treatments- the total number of eggs laid decreased only when 0.2 Gy were delivered at 34.3 Gy/h however, the egg-viability increased. The dose of 0.2 Gy at both DR did not modify the baseline frequency of SLRL. A tendency to decrease in the frequency of lethals in brood III was found in combined treatments at both DR.Conclusion: The fact that 0.2 Gy at 5.4 or 34.3 Gy/h induced an increase in the egg-viability and a tendency to decrease the genetic damage in pre-meiotic cells provoked by 20 Gy, might indicate the induction of any mechanism that could be interpreted as radioprotection in male germ cells of D. melanogaster. Results emphasize the need to carry out more studies on the effect of the DR on the induction of genetic damage in germ cells.
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Affiliation(s)
- Luz Ma Vidal
- Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, México
| | - Emilio Pimentel
- Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, México
| | - Martha P Cruces
- Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, México
| | - Juan C Sánchez-Meza
- Facultad de Química, Universidad Autónoma del Estado de México, Toluca, México
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Hirofuji Y. [13. Basic Concept of Protection Quantities in Health Risk]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2020; 76:755-760. [PMID: 32684569 DOI: 10.6009/jjrt.2020_jjrt_76.7.755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Affiliation(s)
- Yoshiaki Hirofuji
- Cent-Medical Associates LLC
- Faculty of Medicine, University of Tsukuba
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13
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Bando M, Kinugawa T, Manabe Y, Masugi M, Nakajima H, Suzuki K, Tsunoyama Y, Wada T, Toki H. Study of mutation from DNA to biological evolution. Int J Radiat Biol 2019; 95:1390-1403. [DOI: 10.1080/09553002.2019.1606957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Masako Bando
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
| | - Tetsuhiro Kinugawa
- Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Suita, Japan
| | - Yuichiro Manabe
- Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Suita, Japan
| | - Miwako Masugi
- Department of Urology, Shiga University of Medical Science, Shiga, Japan
| | - Hiroo Nakajima
- Institute for Radiation Sciences, Osaka University, Suita, Japan
| | - Kazuyo Suzuki
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yuichi Tsunoyama
- Radioisotope Research Center, Agency for Health, Safety and Environment Kyoto University, Kyoto, Japan
| | - Takahiro Wada
- Department of Pure and Applied Physics, Faculty of Engineering Science, Kansai University, Suita, Japan
| | - Hiroshi Toki
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
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14
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Tsunoyama Y, Suzuki K, Masugi-Tokita M, Nakajima H, Manabe Y, Wada T, Bando M. Verification of a dose rate-responsive dynamic equilibrium model on radiation-induced mutation frequencies in mice. Int J Radiat Biol 2019; 95:1414-1420. [DOI: 10.1080/09553002.2019.1569772] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Yuichi Tsunoyama
- Department of Biology, Radioisotope Research Center, Agency for Health, Safety and Environment, Kyoto University, Kyoto, Japan
| | - Kazuyo Suzuki
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine Kyoto University, Kyoto, Japan
| | | | - Hiroo Nakajima
- Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Yuichiro Manabe
- Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Takahiro Wada
- Department of Pure and Applied Physics, Kansai University, Osaka, Japan
| | - Masako Bando
- Yukawa Institute for Theoretical Physics Kyoto University, Kyoto, Japan
- Research Center for Nuclear Physics, Osaka University, Osaka, Japan
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15
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Space Radiation Effects on Crew During and After Deep Space Missions. CURRENT PATHOBIOLOGY REPORTS 2018. [DOI: 10.1007/s40139-018-0175-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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16
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Braga-Tanaka I, Tanaka S, Kohda A, Takai D, Nakamura S, Ono T, Tanaka K, Komura JI. Experimental studies on the biological effects of chronic low dose-rate radiation exposure in mice: overview of the studies at the Institute for Environmental Sciences. Int J Radiat Biol 2018. [PMID: 29533133 DOI: 10.1080/09553002.2018.1451048] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review summarizes the results of experiments conducted in the Institute for Environmental Sciences for the past 21 years, focusing on the biological effects of long-term low dose-rate radiation exposure on mice. Mice were chronically exposed to gamma rays at dose-rates of 0.05, 1 or 20 mGy/day for 400 days to total doses of 20, 400 or 8000 mGy, respectively. The dose rate 0.05 mGy/day is comparable to the dose limit for radiation workers. The parameters examined were lifespan, neoplasm incidence, antineoplasm immunity, body weight, chromosome aberration(s), gene mutation(s), alterations in mRNA and protein levels and trans-generational effects. At 20 mGy/day, all biological endpoints were significantly altered except neoplasm incidence in the offspring of exposed males. Slight but statistically significant changes in lifespan, neoplasm incidences, chromosome abnormalities and gene expressions were observed at 1 mGy/day. Except for transient alterations in the mRNA levels of some genes and increased liver neoplasm incidence attributed to radiation exposure, the remaining biological endpoints were not influenced after exposure to 0.05 mGy/day. Results suggest that chronic low dose-rate exposure may induce small biological effects.
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Affiliation(s)
- Ignacia Braga-Tanaka
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Satoshi Tanaka
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Atsushi Kohda
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Daisaku Takai
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Shingo Nakamura
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Tetsuya Ono
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Kimio Tanaka
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
| | - Jun-Ichiro Komura
- a Department of Radiobiology , Institute for Environmental Sciences , Rokkasho-mura Kamikita-gun , Aomori-ken , Japan
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Shakeri Manesh S, Sangsuwan T, Pour Khavari A, Fotouhi A, Emami SN, Haghdoost S. MTH1, an 8-oxo-2'-deoxyguanosine triphosphatase, and MYH, a DNA glycosylase, cooperate to inhibit mutations induced by chronic exposure to oxidative stress of ionising radiation. Mutagenesis 2017; 32:389-396. [PMID: 28340109 DOI: 10.1093/mutage/gex003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Our previous results showed that in addition to the immediate interaction of ionising radiation with DNA (direct and indirect effect), low-dose and chronic low-dose rate of irradiation induce endogenous oxidative stress. During oxidative stress, free radicals react with DNA, nucleoside triphosphates (dNTPs), proteins and lipids, and modify their structures. The MYH and MTH1 genes play important roles in preventing mutations induced by 8-hydroxy-guanine, which is an oxidised product of guanine. In this study, we used short-hairpin RNA to permanently knockdown MYH and MTH1 proteins in human lymphoblastoid TK6 cells. Knockdown and wild-type cells were chronically exposed to low dose rates of γ-radiation (between 1.4 and 30 mGy/h). The cells were also subjected to acute doses delivered at a high-dose rate. Growth rate, extracellular 8-hydroxy-2'-deoxyguanosine, clonogenic cell survival and mutant frequencies were analysed in all cell types. A reduced level of cell growth and survival as well as increased mutant frequencies were observed in cells lacking both MYH and MTH1 proteins as compared to cells lacking only MYH and wild-type cells. To sum up, our results suggest that low-dose rates elevate oxidative stress. MTH1 together with MYH plays an important role in protection against mutations induced by modified dNTPs during chronic oxidative stress. In addition, we found no dose-rate effect at the level of mutations in the wild-type TK6 and MYH-KD cells. Our data interestingly indicate a dose-rate threshold for mutation induction in MTH1/MYH double knockdown cells.
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Affiliation(s)
- Sara Shakeri Manesh
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Traimate Sangsuwan
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Ali Pour Khavari
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Asal Fotouhi
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - S Noushin Emami
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Siamak Haghdoost
- Centre for Radiation Protection Research, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
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Nakajima H, Furukawa C, Chang YC, Ogata H, Magae J. Delayed Growth Suppression and Radioresistance Induced by Long-Term Continuous Gamma Irradiation. Radiat Res 2017; 188:181-190. [DOI: 10.1667/rr14666.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Hiroo Nakajima
- Department of Breast Surgery, Misugi-kai Sato Hospital, 65-1 Yabuhigashi-machi, Hirakata-shi, Osaka 573-1124, Japan
| | - Chiharu Furukawa
- Department of Biotechnology, Institute of Research and Innovation, 1201 Takada, Kashiwa 277-0861, Japan
| | - Young-Chae Chang
- Department of Cell Biology, Catholic University of Daegu, School of Medicine, 3056-6 Daemyung-4-Dong, Nam-gu, Daegu 705-718, Republic of Korea
| | - Hiromitsu Ogata
- Center for Public Health Informatics, National Institute of Public Health, 2-3-6 Minami, Wako, Saitama 351-0197, Japan
| | - Junji Magae
- Department of Biotechnology, Institute of Research and Innovation, 1201 Takada, Kashiwa 277-0861, Japan
- Center for Public Health Informatics, National Institute of Public Health, 2-3-6 Minami, Wako, Saitama 351-0197, Japan
- Magae Bioscience Institute, 49-4 Fujimidai, Tsukuba 300-1263, Japan
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry, 2-11-1 Iwado Kita, Komae, Tokyo 201-8511, Japan
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19
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Kodaira M, Asakawa JI, Nakamura N. Radiation-Induced Deletions in Mouse Spermatogonia are Usually Large (over 200 kb) and Contain Little Sequence Similarity at the Junctions. Radiat Res 2017; 187:722-731. [DOI: 10.1667/rr14660.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Mieko Kodaira
- Department of Molecular Biosciences, Radiation Effects Research Foundation, 5-2 Hijiyama Park, Minami-ku, Hiroshima 732-0815, Japan
| | - Jun-ichi Asakawa
- Department of Molecular Biosciences, Radiation Effects Research Foundation, 5-2 Hijiyama Park, Minami-ku, Hiroshima 732-0815, Japan
| | - Nori Nakamura
- Department of Molecular Biosciences, Radiation Effects Research Foundation, 5-2 Hijiyama Park, Minami-ku, Hiroshima 732-0815, Japan
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20
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Beyea J. Lessons to be learned from a contentious challenge to mainstream radiobiological science (the linear no-threshold theory of genetic mutations). ENVIRONMENTAL RESEARCH 2017; 154:362-379. [PMID: 28167448 DOI: 10.1016/j.envres.2017.01.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/25/2017] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
There are both statistically valid and invalid reasons why scientists with differing default hypotheses can disagree in high-profile situations. Examples can be found in recent correspondence in this journal, which may offer lessons for resolving challenges to mainstream science, particularly when adherents of a minority view attempt to elevate the status of outlier studies and/or claim that self-interest explains the acceptance of the dominant theory. Edward J. Calabrese and I have been debating the historical origins of the linear no-threshold theory (LNT) of carcinogenesis and its use in the regulation of ionizing radiation. Professor Calabrese, a supporter of hormesis, has charged a committee of scientists with misconduct in their preparation of a 1956 report on the genetic effects of atomic radiation. Specifically he argues that the report mischaracterized the LNT research record and suppressed calculations of some committee members. After reviewing the available scientific literature, I found that the contemporaneous evidence overwhelmingly favored a (genetics) LNT and that no calculations were suppressed. Calabrese's claims about the scientific record do not hold up primarily because of lack of attention to statistical analysis. Ironically, outlier studies were more likely to favor supra-linearity, not sub-linearity. Finally, the claim of investigator bias, which underlies Calabrese's accusations about key studies, is based on misreading of text. Attention to ethics charges, early on, may help seed a counter narrative explaining the community's adoption of a default hypothesis and may help focus attention on valid evidence and any real weaknesses in the dominant paradigm.
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Affiliation(s)
- Jan Beyea
- Consulting in the Public Interest, Lambertville, NJ 08530, United States.
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21
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Zanzonico P, Dauer L, Strauss HW. Radiobiology in Cardiovascular Imaging. JACC Cardiovasc Imaging 2016; 9:1446-1461. [PMID: 27931527 PMCID: PMC5877470 DOI: 10.1016/j.jcmg.2016.09.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 12/18/2022]
Abstract
The introduction of ionizing radiation in medicine revolutionized the diagnosis and treatment of disease and dramatically improved and continues to improve the quality of health care. Cardiovascular imaging and medical imaging in general, however, are associated with a range of radiobiologic effects, including, in rare instances, moderate to severe skin damage resulting from cardiac fluoroscopy. For the dose range associated with diagnostic imaging (corresponding to effective doses on the order of 10 mSv [1 rem]), the possible effects are stochastic in nature and largely theoretical. The most notable of these effects, of course, is the possible increase in cancer risk. The current review addresses radiobiology relevant to cardiovascular imaging, with particular emphasis on radiation induction of cancer, including consideration of the linear nonthreshold dose-response model and of alternative models such as radiation hormesis.
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Affiliation(s)
- Pat Zanzonico
- Memorial Sloan Kettering Cancer Center, New York, New York.
| | - Lawrence Dauer
- Memorial Sloan Kettering Cancer Center, New York, New York
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22
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Niwa O, Barcellos-Hoff MH, Globus RK, Harrison JD, Hendry JH, Jacob P, Martin MT, Seed TM, Shay JW, Story MD, Suzuki K, Yamashita S. ICRP Publication 131: Stem Cell Biology with Respect to Carcinogenesis Aspects of Radiological Protection. Ann ICRP 2016; 44:7-357. [PMID: 26637346 DOI: 10.1177/0146645315595585] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This report provides a review of stem cells/progenitor cells and their responses to ionising radiation in relation to issues relevant to stochastic effects of radiation that form a major part of the International Commission on Radiological Protection's system of radiological protection. Current information on stem cell characteristics, maintenance and renewal, evolution with age, location in stem cell 'niches', and radiosensitivity to acute and protracted exposures is presented in a series of substantial reviews as annexes concerning haematopoietic tissue, mammary gland, thyroid, digestive tract, lung, skin, and bone. This foundation of knowledge of stem cells is used in the main text of the report to provide a biological insight into issues such as the linear-no-threshold (LNT) model, cancer risk among tissues, dose-rate effects, and changes in the risk of radiation carcinogenesis by age at exposure and attained age. Knowledge of the biology and associated radiation biology of stem cells and progenitor cells is more developed in tissues that renew fairly rapidly, such as haematopoietic tissue, intestinal mucosa, and epidermis, although all the tissues considered here possess stem cell populations. Important features of stem cell maintenance, renewal, and response are the microenvironmental signals operating in the niche residence, for which a well-defined spatial location has been identified in some tissues. The identity of the target cell for carcinogenesis continues to point to the more primitive stem cell population that is mostly quiescent, and hence able to accumulate the protracted sequence of mutations necessary to result in malignancy. In addition, there is some potential for daughter progenitor cells to be target cells in particular cases, such as in haematopoietic tissue and in skin. Several biological processes could contribute to protecting stem cells from mutation accumulation: (a) accurate DNA repair; (b) rapidly induced death of injured stem cells; (c) retention of the DNA parental template strand during divisions in some tissue systems, so that mutations are passed to the daughter differentiating cells and not retained in the parental cell; and (d) stem cell competition, whereby undamaged stem cells outcompete damaged stem cells for residence in the niche. DNA repair mainly occurs within a few days of irradiation, while stem cell competition requires weeks or many months depending on the tissue type. The aforementioned processes may contribute to the differences in carcinogenic radiation risk values between tissues, and may help to explain why a rapidly replicating tissue such as small intestine is less prone to such risk. The processes also provide a mechanistic insight relevant to the LNT model, and the relative and absolute risk models. The radiobiological knowledge also provides a scientific insight into discussions of the dose and dose-rate effectiveness factor currently used in radiological protection guidelines. In addition, the biological information contributes potential reasons for the age-dependent sensitivity to radiation carcinogenesis, including the effects of in-utero exposure.
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23
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Beyea J. Response to, "On the origins of the linear no-threshold (LNT) dogma by means of untruths, artful dodges and blind faith.". ENVIRONMENTAL RESEARCH 2016; 148:527-534. [PMID: 26948286 DOI: 10.1016/j.envres.2016.01.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Revised: 01/24/2016] [Accepted: 01/25/2016] [Indexed: 06/05/2023]
Abstract
It is not true that successive groups of researchers from academia and research institutions-scientists who served on panels of the US National Academy of Sciences (NAS)-were duped into supporting a linear no-threshold model (LNT) by the opinions expressed in the genetic panel section of the 1956 "BEAR I" report. Successor reports had their own views of the LNT model, relying on mouse and human data, not fruit fly data. Nor was the 1956 report biased and corrupted, as has been charged in an article by Edward J. Calabrese in this journal. With or without BEAR I, the LNT model would likely have been accepted in the US for radiation protection purposes in the 1950's.
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Affiliation(s)
- Jan Beyea
- Consulting in the Public Interest, 53 Clinton Street, Lambertville, NJ 08530, USA.
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24
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Sridharan DM, Asaithamby A, Blattnig SR, Costes SV, Doetsch PW, Dynan WS, Hahnfeldt P, Hlatky L, Kidane Y, Kronenberg A, Naidu MD, Peterson LE, Plante I, Ponomarev AL, Saha J, Snijders AM, Srinivasan K, Tang J, Werner E, Pluth JM. Evaluating biomarkers to model cancer risk post cosmic ray exposure. LIFE SCIENCES IN SPACE RESEARCH 2016; 9:19-47. [PMID: 27345199 PMCID: PMC5613937 DOI: 10.1016/j.lssr.2016.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 05/11/2016] [Indexed: 06/06/2023]
Abstract
Robust predictive models are essential to manage the risk of radiation-induced carcinogenesis. Chronic exposure to cosmic rays in the context of the complex deep space environment may place astronauts at high cancer risk. To estimate this risk, it is critical to understand how radiation-induced cellular stress impacts cell fate decisions and how this in turn alters the risk of carcinogenesis. Exposure to the heavy ion component of cosmic rays triggers a multitude of cellular changes, depending on the rate of exposure, the type of damage incurred and individual susceptibility. Heterogeneity in dose, dose rate, radiation quality, energy and particle flux contribute to the complexity of risk assessment. To unravel the impact of each of these factors, it is critical to identify sensitive biomarkers that can serve as inputs for robust modeling of individual risk of cancer or other long-term health consequences of exposure. Limitations in sensitivity of biomarkers to dose and dose rate, and the complexity of longitudinal monitoring, are some of the factors that increase uncertainties in the output from risk prediction models. Here, we critically evaluate candidate early and late biomarkers of radiation exposure and discuss their usefulness in predicting cell fate decisions. Some of the biomarkers we have reviewed include complex clustered DNA damage, persistent DNA repair foci, reactive oxygen species, chromosome aberrations and inflammation. Other biomarkers discussed, often assayed for at longer points post exposure, include mutations, chromosome aberrations, reactive oxygen species and telomere length changes. We discuss the relationship of biomarkers to different potential cell fates, including proliferation, apoptosis, senescence, and loss of stemness, which can propagate genomic instability and alter tissue composition and the underlying mRNA signatures that contribute to cell fate decisions. Our goal is to highlight factors that are important in choosing biomarkers and to evaluate the potential for biomarkers to inform models of post exposure cancer risk. Because cellular stress response pathways to space radiation and environmental carcinogens share common nodes, biomarker-driven risk models may be broadly applicable for estimating risks for other carcinogens.
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Affiliation(s)
| | | | - Steve R Blattnig
- Langley Research Center, Langley Research Center (LaRC), VA, United States
| | - Sylvain V Costes
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | | | | | | | - Lynn Hlatky
- CCSB-Tufts School of Medicine, Boston, MA, United States
| | - Yared Kidane
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Amy Kronenberg
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Mamta D Naidu
- CCSB-Tufts School of Medicine, Boston, MA, United States
| | - Leif E Peterson
- Houston Methodist Research Institute, Houston, TX, United States
| | - Ianik Plante
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Artem L Ponomarev
- Wyle Science, Technology & Engineering Group, Houston, TX, United States
| | - Janapriya Saha
- UT Southwestern Medical Center, Dallas, TX, United States
| | | | | | - Jonathan Tang
- Exogen Biotechnology, Inc., Berkeley, CA, United States
| | | | - Janice M Pluth
- Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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25
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Wada T, Manabe Y, Nakamura I, Tsunoyama Y, Nakajima H, Bando M. Dose and dose-rate dependence of mutation frequency under long-term exposure – a new look at DDREF from WAM model. J NUCL SCI TECHNOL 2016. [DOI: 10.1080/00223131.2016.1164635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Takahiro Wada
- Department of Pure and Applied Physics, Kansai University, Suita, Osaka, Japan
| | - Yuichiro Manabe
- Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan
| | - Issei Nakamura
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, P. R. China
| | - Yuichi Tsunoyama
- Division of Biology, Radioisotope Research Center, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Hiroo Nakajima
- Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Masako Bando
- Yukawa Institute for Theoretical Physics, Kyoto University, Sakyo-ku, Kyoto, Japan
- Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka, Japan
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26
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27
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Rühm W, Woloschak GE, Shore RE, Azizova TV, Grosche B, Niwa O, Akiba S, Ono T, Suzuki K, Iwasaki T, Ban N, Kai M, Clement CH, Bouffler S, Toma H, Hamada N. Dose and dose-rate effects of ionizing radiation: a discussion in the light of radiological protection. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2015; 54:379-401. [PMID: 26343037 DOI: 10.1007/s00411-015-0613-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 08/18/2015] [Indexed: 05/21/2023]
Abstract
The biological effects on humans of low-dose and low-dose-rate exposures to ionizing radiation have always been of major interest. The most recent concept as suggested by the International Commission on Radiological Protection (ICRP) is to extrapolate existing epidemiological data at high doses and dose rates down to low doses and low dose rates relevant to radiological protection, using the so-called dose and dose-rate effectiveness factor (DDREF). The present paper summarizes what was presented and discussed by experts from ICRP and Japan at a dedicated workshop on this topic held in May 2015 in Kyoto, Japan. This paper describes the historical development of the DDREF concept in light of emerging scientific evidence on dose and dose-rate effects, summarizes the conclusions recently drawn by a number of international organizations (e.g., BEIR VII, ICRP, SSK, UNSCEAR, and WHO), mentions current scientific efforts to obtain more data on low-dose and low-dose-rate effects at molecular, cellular, animal and human levels, and discusses future options that could be useful to improve and optimize the DDREF concept for the purpose of radiological protection.
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Affiliation(s)
- Werner Rühm
- Institute of Radiation Protection, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Gayle E Woloschak
- Department of Radiation Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Roy E Shore
- Radiation Effects Research Foundation (RERF), 5-2 Hijiyama Park, Minami-ku, Hiroshima City, 732-0815, Japan
| | - Tamara V Azizova
- Southern Urals Biophysics Institute (SUBI), Ozyorskoe Shosse 19, Ozyorsk, Chelyabinsk Region, Russian Federation, 456780
| | - Bernd Grosche
- Federal Office for Radiation Protection, Ingolstaedter Landstr. 1, 85764, Oberschleissheim, Germany
| | - Ohtsura Niwa
- Fukushima Medical University, Hikarigaoka 1, Fukushima, 960-1295, Japan
| | - Suminori Akiba
- Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima City, Japan
| | - Tetsuya Ono
- Institute for Environmental Sciences, 1-7 Ienomae, Rokkasho, Aomori-ken, 039-3212, Japan
| | - Keiji Suzuki
- Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan
| | - Toshiyasu Iwasaki
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Tokyo, 201-8511, Japan
| | - Nobuhiko Ban
- Faculty of Nursing, Tokyo Healthcare University, 2-5-1 Higashigaoka, Meguro, Tokyo, 152-8558, Japan
| | - Michiaki Kai
- Department of Environmental Health Science, Oita University of Nursing and Health Sciences, 2944-9 Megusuno, Oita, 840-1201, Japan
| | - Christopher H Clement
- International Commission on Radiological Protection (ICRP), PO Box 1046, Station B, 280 Slater Street, Ottawa, ON, K1P 5S9, Canada
| | - Simon Bouffler
- Centre for Radiation, Chemical and Environmental Hazards, Public Health England (PHE), Chilton, Didcot, OX11 ORQ, UK
| | - Hideki Toma
- JAPAN NUS Co., Ltd. (JANUS), 7-5-25 Nishi-Shinjuku, Shinjuku-Ku, Tokyo, 160-0023, Japan
| | - Nobuyuki Hamada
- International Commission on Radiological Protection (ICRP), PO Box 1046, Station B, 280 Slater Street, Ottawa, ON, K1P 5S9, Canada.
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28
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Hatada S, Subramanian A, Mandefro B, Ren S, Kim HW, Tang J, Funari V, Baloh RH, Sareen D, Arumugaswami V, Svendsen CN. Low-Dose Irradiation Enhances Gene Targeting in Human Pluripotent Stem Cells. Stem Cells Transl Med 2015; 4:998-1010. [PMID: 26185257 DOI: 10.5966/sctm.2015-0050] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 05/27/2015] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Human pluripotent stem cells (hPSCs) are now being used for both disease modeling and cell therapy; however, efficient homologous recombination (HR) is often crucial to develop isogenic control or reporter lines. We showed that limited low-dose irradiation (LDI) using either γ-ray or x-ray exposure (0.4 Gy) significantly enhanced HR frequency, possibly through induction of DNA repair/recombination machinery including ataxia-telangiectasia mutated, histone H2A.X and RAD51 proteins. LDI could also increase HR efficiency by more than 30-fold when combined with the targeting tools zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats. Whole-exome sequencing confirmed that the LDI administered to hPSCs did not induce gross genomic alterations or affect cellular viability. Irradiated and targeted lines were karyotypically normal and made all differentiated lineages that continued to express green fluorescent protein targeted at the AAVS1 locus. This simple method allows higher throughput of new, targeted hPSC lines that are crucial to expand the use of disease modeling and to develop novel avenues of cell therapy. SIGNIFICANCE The simple and relevant technique described in this report uses a low level of radiation to increase desired gene modifications in human pluripotent stem cells by an order of magnitude. This higher efficiency permits greater throughput with reduced time and cost. The low level of radiation also greatly increased the recombination frequency when combined with developed engineered nucleases. Critically, the radiation did not lead to increases in DNA mutations or to reductions in overall cellular viability. This novel technique enables not only the rapid production of disease models using human stem cells but also the possibility of treating genetically based diseases by correcting patient-derived cells.
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Affiliation(s)
- Seigo Hatada
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Aparna Subramanian
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Berhan Mandefro
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Songyang Ren
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Ho Won Kim
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Jie Tang
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Vincent Funari
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Robert H Baloh
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Dhruv Sareen
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Vaithilingaraja Arumugaswami
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Clive N Svendsen
- Board of Governors, Regenerative Medicine Institute, Department of Biomedical Sciences, iPSC Core, The David and Janet Polak Foundation Stem Cell Core Laboratory, Genomics Core Facility, Department of Surgery, and Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, California, USA
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Otsuka K, Iwasaki T. Effects of dose rates on radiation-induced replenishment of intestinal stem cells determined by Lgr5 lineage tracing. JOURNAL OF RADIATION RESEARCH 2015; 56:615-22. [PMID: 25832104 PMCID: PMC4497386 DOI: 10.1093/jrr/rrv012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 02/16/2015] [Indexed: 05/05/2023]
Abstract
An understanding of the dynamics of intestinal Lgr5(+) stem cells is important for elucidating the mechanism of colonic cancer development. We previously established a method for evaluating Lgr5(+) stem cells by tamoxifen-dependent Lgr5-lineage tracing and showed that high-dose-rate radiation stimulated replenishment of colonic stem cells. In this study, we evaluated the effects of low-dose-rate radiation on stem cell maintenance. Tamoxifen (4OHT)-injected Lgr5-EGFP-IRES-Cre(ERT2) × ROSA-LSL-LacZ mice were used, LacZ-labeled colonic crypts were enumerated, and the loss of LacZ(+) crypts under low-dose-rate radiation was estimated. After 4OHT treatment, the number of LacZ-labeled Lgr5(+) stem cells was higher in the colon of infant mice than in adult mice. The percentage of LacZ-labeled crypts in infant mice rapidly decreased after 4OHT treatment. However, the percentage of labeled crypts plateaued at ∼2% at 4 weeks post-treatment and remained unchanged for up to 7 months. Thus, it will be advantageous to evaluate the long-term effects of low-dose-rate radiation. Next, we determined the percentages of LacZ-labeled crypts irradiated with 1 Gy administered at different dose rates. As reported in our previous study, mice exposed to high-dose-rate radiation (30 Gy/h) showed a marked replenishment (P = 0.04). However, mice exposed to low-dose-rate radiation (0.003 Gy/h) did not exhibit accelerated stem-cell replenishment (P = 0.47). These findings suggest the percentage of labeled crypts can serve as a useful indicator of the effects of dose rate on the stem cell pool.
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Affiliation(s)
- Kensuke Otsuka
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
| | - Toshiyasu Iwasaki
- Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan
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30
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Adewoye AB, Lindsay SJ, Dubrova YE, Hurles ME. The genome-wide effects of ionizing radiation on mutation induction in the mammalian germline. Nat Commun 2015; 6:6684. [PMID: 25809527 PMCID: PMC4389250 DOI: 10.1038/ncomms7684] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 02/17/2015] [Indexed: 01/12/2023] Open
Abstract
The ability to predict the genetic consequences of human exposure to ionizing radiation has been a long-standing goal of human genetics in the past 50 years. Here we present the results of an unbiased, comprehensive genome-wide survey of the range of germline mutations induced in laboratory mice after parental exposure to ionizing radiation and show irradiation markedly alters the frequency and spectrum of de novo mutations. Here we show that the frequency of de novo copy number variants (CNVs) and insertion/deletion events (indels) is significantly elevated in offspring of exposed fathers. We also show that the spectrum of induced de novo single-nucleotide variants (SNVs) is strikingly different; with clustered mutations being significantly over-represented in the offspring of irradiated males. Our study highlights the specific classes of radiation-induced DNA lesions that evade repair and result in germline mutation and paves the way for similarly comprehensive characterizations of other germline mutagens.
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Affiliation(s)
- Adeolu B. Adewoye
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK
| | - Sarah J. Lindsay
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Yuri E. Dubrova
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK
| | - Matthew E. Hurles
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
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31
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Nenoi M, Wang B, Vares G. In vivo radioadaptive response: a review of studies relevant to radiation-induced cancer risk. Hum Exp Toxicol 2015; 34:272-83. [PMID: 24925363 PMCID: PMC4442823 DOI: 10.1177/0960327114537537] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Radioadaptive response (RAR) describes phenomena where small conditioning doses of ionizing radiation (IR) reduce detrimental effects of subsequent higher IR doses. Current radiation protection regulations do not include RAR because of the large variability in expression among individuals and uncertainties of the mechanism. However, RAR should be regarded as an indispensable factor for estimation and control of individual IR sensitivity. In this article, RAR studies relevant to individual cancer risk are reviewed. Using various stains of mice, carcinogenic RAR has been demonstrated. Consistently much in vivo evidence for RAR with end points of DNA and chromosome damage is reported. Most in vivo RAR studies revealed efficient induction of RAR by chronic or repeated low-dose priming irradiation. Chronic IR-induced RAR was observed also in human individuals after environmental, occupational, and nuclear accident radiation exposure. These observations may be associated with an intrinsically distinct feature of in vivo experimental systems that mainly consist of nonproliferating mature cells. Alternatively, induction of RAR by gap junction-mediated bystander effects suggests that multicellular systems comprising densely communicating cells may be capable of responding to long-lasting low-dose-rate priming irradiation. Regulation by endocrine factors is also a plausible mechanism for RAR at an individual level. Emerging evidence suggests that glucocorticoids, known as stress hormones, participate in in vivo RAR induction following long-term low-dose-rate exposure to IR.
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Affiliation(s)
- M Nenoi
- Research Center for Radiation Protection, National Institute of Radiological Sciences, Inage-ku, Chiba, Japan
| | - B Wang
- Research Center for Radiation Protection, National Institute of Radiological Sciences, Inage-ku, Chiba, Japan
| | - G Vares
- Research Center for Radiation Protection, National Institute of Radiological Sciences, Inage-ku, Chiba, Japan
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32
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Murakami M, Oki T. Estimated dietary intake of radionuclides and health risks for the citizens of Fukushima City, Tokyo, and Osaka after the 2011 nuclear accident. PLoS One 2014; 9:e112791. [PMID: 25390339 PMCID: PMC4229249 DOI: 10.1371/journal.pone.0112791] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 10/19/2014] [Indexed: 11/18/2022] Open
Abstract
The radionuclides released from the Fukushima Daiichi nuclear power plant in 2011 pose a health risk. In this study, we estimated the 1st-year average doses resulting from the intake of iodine 131 (131I) and cesium 134 and 137 (134Cs and 137Cs) in drinking water and food ingested by citizens of Fukushima City (∼50 km from the nuclear power plant; outside the evacuation zone), Tokyo (∼230 km), and Osaka (∼580 km) after the accident. For citizens in Fukushima City, we considered two scenarios: Case 1, citizens consumed vegetables bought from markets; Case 2, citizens consumed vegetables grown locally (conservative scenario). The estimated effective doses of 134Cs and 137Cs agreed well with those estimated through market basket and food-duplicate surveys. The average thyroid equivalent doses due to ingestion of 131I for adults were 840 µSv (Case 1) and 2700 µSv (Case 2) in Fukushima City, 370 µSv in Tokyo, and 16 µSv in Osaka. The average effective doses due to 134Cs and 137Cs were 19, 120, 6.1, and 1.9 µSv, respectively. The doses estimated in this study were much lower than values reported by the World Health Organization and the United Nations Scientific Committee on the Effects of Atomic Radiation, whose assessments lacked validation and full consideration of regional trade in foods, highlighting the importance of including regional trade. The 95th percentile effective doses were 2–3 times the average values. Lifetime attributable risks (LARs) of thyroid cancers due to ingestion were 2.3–39×10−6 (Case 1) and 10–98×10−6 (Case 2) in Fukushima City, 0.95–14×10−6 in Tokyo, and 0.11–1.3×10−6 in Osaka. The contributions of LARs of thyroid cancers due to ingestion were 7.5%–12% of all exposure (Case 1) and 12%–30% (Case 2) in Fukushima City.
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Affiliation(s)
- Michio Murakami
- Institute of Industrial Science, The University of Tokyo, Meguro, Tokyo, Japan
- Japan Science and Technology Agency, Core Research for Evolutionary Science and Technology (CREST), Chiyoda, Tokyo, Japan
- * E-mail:
| | - Taikan Oki
- Institute of Industrial Science, The University of Tokyo, Meguro, Tokyo, Japan
- Japan Science and Technology Agency, Core Research for Evolutionary Science and Technology (CREST), Chiyoda, Tokyo, Japan
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33
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Tanaka K, Satoh K, Kohda A. Dose and dose-rate response of lymphocyte chromosome aberrations in mice chronically irradiated within a low-dose-rate range after age adjustment. RADIATION PROTECTION DOSIMETRY 2014; 159:38-45. [PMID: 24870362 DOI: 10.1093/rpd/ncu173] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The incidences of chromosome aberrations were analysed in splenic lymphocytes from mice that were continuously exposed to (137)Cs gamma rays within the low-dose-rate (LDR) range to evaluate the dose-response and dose-rate effects. Chromosome aberrations were detected by fluorescence in situ hybridisation method, and these were found to increase in frequency up to 8000 mGy at 20 mGy for 22 h d(-1) and to 700 mGy at 1 mGy for 22 h d(-1). Translocations increased in a linear quadratic manner with age in non-exposed mice. The dose-response relationship for the frequency of translocations at each dose rate (20 and 1 mGy for 22 h d(-1)) was obtained using age-adjusted multiple linear regression analysis. Values of the linear term, shown as the slope, decreased as the dose rate was reduced from 20 to 1 mGy for 22 h d(-1), indicating a positive dose-rate effect in the LDR range. These results will be useful for estimating the risk of LDR radiation exposure and radiation protection.
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Affiliation(s)
- K Tanaka
- Department of Radiobiology, Institute for Environmental Sciences, 2-121 Hachazawa, Takahoko, Rokkasho, Kamikita, Aomori 039-3213, Japan
| | - K Satoh
- Department of Environmetrics and Biometrics, Institute for Radiation Biology and Medicine, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima, Hiroshima 734-8551, Japan
| | - A Kohda
- Department of Radiobiology, Institute for Environmental Sciences, 2-121 Hachazawa, Takahoko, Rokkasho, Kamikita, Aomori 039-3213, Japan
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Manesh SS, Deperas-Kaminska M, Fotouhi A, Sangsuwan T, Harms-Ringdahl M, Wojcik A, Haghdoost S. Mutations and chromosomal aberrations in hMTH1-transfected and non-transfected TK6 cells after exposure to low dose rates of gamma radiation. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2014; 53:417-425. [PMID: 24549366 DOI: 10.1007/s00411-014-0521-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 02/02/2014] [Indexed: 06/03/2023]
Abstract
The aim of the present study was to analyse the dose rate effect of gamma radiation at the level of mutations, chromosomal aberrations, and cell growth in TK6 cells with normal as well as reduced levels of hMTH1 protein. TK6 cells were exposed to gamma radiation at dose rates ranging from 1.4 to 30.0 mGy/h (chronic exposure) as well as 24 Gy/h (acute exposure). Cell growth, frequency of thymidine kinase mutants, and of chromosomal aberrations in painted chromosomes 2, 8, and 14 were analysed. A decline in cell growth and an increase in unstable-type chromosomal aberrations with increasing dose rate were observed in both cell lines. A dose rate effect was not seen on mutations or stable-type chromosomal aberrations in any of the two cell lines. Reduction in the hMTH1 protein does not influence the sensitivity of TK6 cells to gamma radiation. This result fits well with data of others generated with the same cell line.
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Affiliation(s)
- Sara Shakeri Manesh
- Department of Molecular Biosciences, Centre for Radiation Protection Research (CRPR), The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
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35
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Sarapultseva EI, Igolkina JV, Tikhonov VN, Dubrova YE. The in vivo effects of low-intensity radiofrequency fields on the motor activity of protozoa. Int J Radiat Biol 2014; 90:262-7. [DOI: 10.3109/09553002.2014.868612] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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36
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The Mouse House: A brief history of the ORNL mouse-genetics program, 1947–2009. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2013; 753:69-90. [DOI: 10.1016/j.mrrev.2013.08.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/12/2013] [Indexed: 11/20/2022]
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37
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Tanaka K, Kohda A, Satoh K. Dose-rate effects and dose and dose-rate effectiveness factor on frequencies of chromosome aberrations in splenic lymphocytes from mice continuously exposed to low-dose-rate gamma-radiation. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2013; 33:61-70. [PMID: 23295730 DOI: 10.1088/0952-4746/33/1/61] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Dose-rate effects on chromosome aberrations in the low-dose-rate range have not been evaluated previously. The incidences of chromosome aberrations were analysed in splenic lymphocytes from female specific pathogen-free (SPF) C3H mice that were continuously irradiated with low- or medium-dose-rate (LDR, MDR) (137)Cs γ rays from 56 days of age to evaluate the dose-rate effects. The dose-response relationship for the frequency of dicentric chromosome aberration at each dose rate (400 mGy/22h/day, 20 mGy/22h/day and 1 mGy/22h/day) was obtained using age-adjusted multiple linear regression analysis assuming that the relationship can be represented by a linear or linear quadratic model and a test for the difference between the irradiated group and the non-irradiated group. Values of the linear term, shown as the slope, decreased as the dose rate was reduced from 400 mGy/22h/day (18.2 mGy h(-1)) to 1 mGy/22h/day (0.045 mGy h(-1)), indicating a positive dose-rate effect in the dose-rate region. The incidences of dicentric chromosomes and translocation for LDR (20 mGy day(-1)) were compared with those for HDR (890 mGy min(-1)) irradiation at each total dose to obtain the dose and dose-rate effectiveness factor (DDREF). The DDREFs were 4.5 for dicentrics and 2.3 for translocations at a total dose of 100 mGy based on the chromosome aberration rate. These results will be useful for estimating the risk of LDR radiation exposure and radiation protection.
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Affiliation(s)
- Kimio Tanaka
- Department of Radiobiology, Institute for Environmental Sciences (IES), 2-121 Hachazawa, Takahoko, Rokkasho, Kamikita, Aomori 039-3213, Japan.
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38
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Mughal SK, Myazin AE, Zhavoronkov LP, Rubanovich AV, Dubrova YE. The dose and dose-rate effects of paternal irradiation on transgenerational instability in mice: a radiotherapy connection. PLoS One 2012; 7:e41300. [PMID: 22911775 PMCID: PMC3404076 DOI: 10.1371/journal.pone.0041300] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 06/19/2012] [Indexed: 01/08/2023] Open
Abstract
The non-targeted effects of human exposure to ionising radiation, including transgenerational instability manifesting in the children of irradiated parents, remains poorly understood. Employing a mouse model, we have analysed whether low-dose acute or low-dose-rate chronic paternal γ-irradiation can destabilise the genomes of their first-generation offspring. Using single-molecule PCR, the frequency of mutation at the mouse expanded simple tandem repeat (ESTR) locus Ms6-hm was established in DNA samples extracted from sperm of directly exposed BALB/c male mice, as well as from sperm and the brain of their first-generation offspring. For acute γ-irradiation from 10–100 cGy a linear dose-response for ESTR mutation induction was found in the germ line of directly exposed mice, with a doubling dose of 57 cGy. The mutagenicity of acute exposure to 100 cGy was more pronounced than that for chronic low-dose-rate irradiation. The analysis of transgenerational effects of paternal irradiation revealed that ESTR mutation frequencies were equally elevated in the germ line (sperm) and brain of the offspring of fathers exposed to 50 and 100 cGy of acute γ-rays. In contrast, neither paternal acute irradiation at lower doses (10–25 cGy), nor low-dose-rate exposure to 100 cGy affected stability of their offspring. Our data imply that the manifestation of transgenerational instability is triggered by a threshold dose of acute paternal irradiation. The results of our study also suggest that most doses of human exposure to ionising radiation, including radiotherapy regimens, may be unlikely to result in transgenerational instability in the offspring children of irradiated fathers.
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Affiliation(s)
- Safeer K. Mughal
- Department of Genetics, University of Leicester, Leicester, United Kingdom
| | - Andrey E. Myazin
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Leonid P. Zhavoronkov
- Medical Radiological Research Center of the Russian Ministry of Health and Social Development, Obninsk, Russia
| | | | - Yuri E. Dubrova
- Department of Genetics, University of Leicester, Leicester, United Kingdom
- * E-mail:
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39
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Russell LB, Hunsicker PR. The effect of dose rate on the frequency of specific-locus mutations induced in mouse spermatogonia is restricted to larger lesions; a retrospective analysis of historical data. Radiat Res 2012; 177:555-64. [PMID: 22397578 DOI: 10.1667/rr2853.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A series of 19 large-scale germ-cell mutagenesis experiments conducted several decades ago led to the conclusion that low-LET radiation delivered to mouse spermatogonia at dose rates of 0.8 R/min and below induced only about one-third as many specific-locus mutations as did single, acute exposures at 24 R/min and above. A two-hit origin of the mutations was deemed unlikely in view of the then prevailing evidence for the small size of genetic lesions in spermatogonia. Instead, the dose-rate effect was hypothesized to be the result of a repair system that exists in spermatogonia, but not in more mature male reproductive cells. More recent genetic and molecular studies on the marker genes have identified the phenotypes associated with specific states of the mutant chromosomes, and it is now possible retrospectively to classify individual past mutations as "large lesions" or "other lesions". The mutation-frequency difference between high and low dose rates is restricted to the large lesion mutations, for which the dose-curve slopes differ by a factor exceeding 3.4. For other lesion mutations, there is essentially no difference between the slopes for protracted and acute irradiations; induced other lesions frequencies per unit dose remain similar for dose rates ranging over more than 7 orders of magnitude. For large lesions, these values rise sharply at dose rates >0.8 R/min, though they remain similar within the whole range of protracted doses, failing to provide evidence for a threshold dose rate. The downward bend at high doses that had been noted for X-ray-induced specific-locus mutations as a whole and ascribed to a positive correlation between spermatogonial death and mutation load is now found to be restricted to large lesion mutations. There is a marked difference between the mutation spectra (distributions among the seven loci) for large lesions and other lesions. Within each class, however, the spectra are similar for acute and protracted irradiation.
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Affiliation(s)
- Liane B Russell
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA.
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40
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Koana T, Takahashi T, Tsujimura H. Reduction of Spontaneous Somatic Mutation Frequency by a Low-Dose X Irradiation ofDrosophilaLarvae and Possible Involvement of DNA Single-Strand Damage Repair. Radiat Res 2012; 177:265-71. [DOI: 10.1667/rr2630.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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41
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42
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Isobe T. [The essential knowledge for exposition of radiation protection]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2012; 68:1419-1427. [PMID: 23089847 DOI: 10.6009/jjrt.2012_jsrt_68.10.1419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
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43
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Magae J, Furukawa C, Ogata H. Dose-Rate Effect on Proliferation Suppression in Human Cell Lines Continuously Exposed to γ Rays. Radiat Res 2011; 176:447-58. [DOI: 10.1667/rr2408.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Junji Magae
- Institute of Research and Innovation, 1201 Takada, Kashiwa 277-0861, Japan
| | - Chiharu Furukawa
- Institute of Research and Innovation, 1201 Takada, Kashiwa 277-0861, Japan
| | - Hiromitsu Ogata
- National Institute of Public Health, 2-3-6, Minami, Wako, Saitama 351-0197 Japan
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44
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Koana T, Tsujimura H. A U-shaped dose-response relationship between x radiation and sex-linked recessive lethal mutation in male germ cells of Drosophila. Radiat Res 2010; 174:46-51. [PMID: 20681798 DOI: 10.1667/rr2085.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We reported previously that low-dose X irradiation of DNA repair-proficient immature sperm of wild-type Drosophila melanogaster at a low dose rate (50 mGy/min) resulted in a mutation frequency that was lower than that in the sham-irradiated group. Therefore, a U-shaped dose-response relationship was suggested. Here we show that the dose-response curve is actually U-shaped by carrying out a large-scale sex-linked recessive lethal assay using Drosophila. No reduction of the mutation frequency was observed in a strain mutant for the nucleotide excision repair gene mei-9a (Drosophila homologue of human XPF). Introduction of a chromosome fragment containing mei-9+ into the mei-9a mutant strain restored the reduction of the mutation frequency in the low-dose-irradiated group. These results showed that DNA repair was responsible for the U-shaped dose-response relationship in Drosophila.
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Affiliation(s)
- Takao Koana
- Radiation Safety Research Center, Central Research Institute of Electric Power Industry, Komae, Tokyo 201-8511, Japan.
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45
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Uehara Y, Ito Y, Taki K, Nenoi M, Ichinohe K, Nakamura S, Tanaka S, Oghiso Y, Tanaka K, Matsumoto T, Paunesku T, Woloschak GE, Ono T. Gene Expression Profiles in Mouse Liver after Long-Term Low-Dose-Rate Irradiation with Gamma Rays. Radiat Res 2010; 174:611-7. [DOI: 10.1667/rr2195.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Yoshihiko Uehara
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Yasuko Ito
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Keiko Taki
- Radiation Effect Mechanisms Research Group, National Institute of Radiological Sciences, Chiba 263-8555, Japan
| | - Mitsuru Nenoi
- Radiation Effect Mechanisms Research Group, National Institute of Radiological Sciences, Chiba 263-8555, Japan
| | - Kazuaki Ichinohe
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Shingo Nakamura
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Satoshi Tanaka
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Yoichi Oghiso
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Kimio Tanaka
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Tsuneya Matsumoto
- Department of Radiobiology, Institute for Environmental Sciences, Aomori 039-3212, Japan
| | - Tatjana Paunesku
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Gayle E. Woloschak
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Tetsuya Ono
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
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46
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Okudaira N, Uehara Y, Fujikawa K, Kagawa N, Ootsuyama A, Norimura T, Saeki KI, Nohmi T, Masumura KI, Matsumoto T, Oghiso Y, Tanaka K, Ichinohe K, Nakamura S, Tanaka S, Ono T. Radiation Dose-Rate Effect on Mutation Induction in Spleen and Liver of gpt delta Mice. Radiat Res 2010; 173:138-47. [DOI: 10.1667/rr1932.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Naohito Okudaira
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Yoshihiko Uehara
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Kazuo Fujikawa
- Deparment of Life Science, Faculty of Science and Technology, Kinki University, Kowakae, Higashiosaka 577-8502, Japan
| | - Nao Kagawa
- Deparment of Life Science, Faculty of Science and Technology, Kinki University, Kowakae, Higashiosaka 577-8502, Japan
| | - Akira Ootsuyama
- Department of Radiation Biology and Health, University of Occupational and Environmental Health, Kitakyushu, 807-8555, Japan
| | - Toshiyuki Norimura
- Department of Radiation Biology and Health, University of Occupational and Environmental Health, Kitakyushu, 807-8555, Japan
| | - Ken-ichi Saeki
- Yokohama College of Pharmacy, Totsuka-ku, Yokohama 245-0066, Japan
| | - Takehiko Nohmi
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
| | - Ken-ichi Masumura
- Division of Genetics and Mutagenesis, National Institute of Health Sciences, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
| | - Tsuneya Matsumoto
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Yoichi Oghiso
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Kimio Tanaka
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Kazuaki Ichinohe
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Shingo Nakamura
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Satoshi Tanaka
- Institute for Environmental Sciences, Rokkasho, Aomori 039-3212, Japan
| | - Tetsuya Ono
- Department of Cell Biology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
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47
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Kuhne WW, Gersey BB, Wilkins R, Wu H, Wender SA, George V, Dynan WS. Biological effects of high-energy neutrons measured in vivo using a vertebrate model. Radiat Res 2009; 172:473-80. [PMID: 19772468 DOI: 10.1667/rr1556.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Interaction of solar protons and galactic cosmic radiation with the atmosphere and other materials produces high-energy secondary neutrons from below 1 to 1000 MeV and higher. Although secondary neutrons may provide an appreciable component of the radiation dose equivalent received by space and high-altitude air travelers, the biological effects remain poorly defined, particularly in vivo in intact organisms. Here we describe the acute response of Japanese medaka (Oryzias latipes) embryos to a beam of high-energy spallation neutrons that mimics the energy spectrum of secondary neutrons encountered aboard spacecraft and high-altitude aircraft. To determine RBE, embryos were exposed to 0-0.5 Gy of high-energy neutron radiation or 0-15 Gy of reference gamma radiation. The radiation response was measured by imaging apoptotic cells in situ in defined volumes of the embryo, an assay that provides a quantifiable, linear dose response. The slope of the dose response in the developing head, relative to reference gamma radiation, indicates an RBE of 24.9 (95% CI 13.6-40.7). A higher RBE of 48.1 (95% CI 30.0-66.4) was obtained based on overall survival. A separate analysis of apoptosis in muscle showed an overall nonlinear response, with the greatest effects at doses of less than 0.3 Gy. Results of this experiment indicate that medaka are a useful model for investigating biological damage associated with high-energy neutron exposure.
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Affiliation(s)
- Wendy W Kuhne
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, Georgia 30912, USA.
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48
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Shin SC, Kang YM, Jin YW, Kim HS. Relative morphological abnormalities of sperm in the caudal epididymis of high- and low-dose-rate gamma-irradiated ICR mice. JOURNAL OF RADIATION RESEARCH 2009; 50:261-266. [PMID: 19531924 DOI: 10.1269/jrr.09005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This study evaluated the effects of low dose radiation on spermatogenic cells using the morphological characteristics of sperm in the caudal epididymis of ICR mice. In this study, six abnormal sperm shapes (amorphous heads, blunt hooks, excessive hooks, two heads and tails, folded tails and short tails) were observed at eight days after gamma-irradiation ((137)Cs, 0, 0.2, 0.5, 1, 2 or 4 Gy) with both a high-dose-rate (0.8 Gy/min) and a low-dose-rate (0.7 mGy/hr). Fewer abnormal forms of sperm were observed in low-dose-rate irradiated mice than in mice that received a high-dose-rate irradiation (P = 0.002). The ratio of the dose rate effect among low-dose-rate irradiated mice to high-dose-rate irradiated mice was approximately 0.6. In addition, sperm with blunt hooks and two heads and tails significantly increased in number after irradiation, potentially providing an endpoint marker for estimating the effects of radiation. This study suggests that low-dose-rate (0.7 mGy/hr) radiation does not damage stem spermatogonia and probably stimulates repair in damaged spermatogonial stem cells in male mice.
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Affiliation(s)
- Suk Chul Shin
- Radiation Health Research Institute, Korea Hydro & Nuclear Power Co., Ltd., 388-1 Ssangmun-dong, Dobong-gu, Seoul, Korea
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49
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Tanaka K, Kohda A, Satoh K, Toyokawa T, Ichinohe K, Ohtaki M, Oghiso Y. Dose-rate effectiveness for unstable-type chromosome aberrations detected in mice after continuous irradiation with low-dose-rate gamma rays. Radiat Res 2009; 171:290-301. [PMID: 19267556 DOI: 10.1667/rr1238.1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Chronological changes in the chromosome aberration rates of splenocytes from specific-pathogen-free (SPF) mice after continuous and long-term exposure to low-dose-rate gamma rays were studied. Incidences of dicentrics plus centric rings (Dic+Rc), detected by conventional Giemsa staining, and dicentric chromosomes, detected by fluorescence in situ hybridization (Dic by FISH) using a centromere probe, showed an essentially linear increase up to a total accumulated dose of 8000 mGy after irradiation for about 400 days at a low dose rate of 20 mGy/day. For comparison, acute high-dose-rate and medium-dose-rate irradiation were performed. The values of the alpha coefficients in the linear regression lines for these unstable-type aberrations decreased as the dose rates were lowered from medium dose rates (200 and 400 mGy/day) to low dose rates (1 and 20 mGy/day). The dose and dose-rate effectiveness factor (DDREF), estimated by the ratio of calculated incidences using the best-fit regression lines at a high dose rate (890 mGy/min) and low dose rate (20 mGy/day), was 4.5 for Dic by FISH and 5.2 for Dic+Rc, respectively, at the same dose of 100 mGy, while different DDREFs were obtained for different accumulated doses. This is the first study to provide information regarding the effects of long-term exposure to low-dose-rate radiation on chromosomes.
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Affiliation(s)
- Kimio Tanaka
- Department of Radiobiology, Institute for Environmental Sciences, Hacchazawa 2-121, Takahoko, Rokkasho, Kamikita, Aomori 039-3213, Japan.
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50
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Ono T, Uehara Y, Okudaira N, Fujikawa K, Kagawa N, Yoshida M, Hayata I, Nohmi T, Matsumoto T, Oghiso Y, Tanaka K, Ichinohe K, Nakamura S, Tanaka S. Alteration of Genome Structure Induced by Very Low Dose-Rate Irradiation in Mouse Tissues. DATA SCIENCE JOURNAL 2009. [DOI: 10.2481/dsj.br-05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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