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Nakajima Tetsuo - One of the best experts on this subject based on the ideXlab platform.
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Effects from Chronic Restraint-Induced Stress and Total Body Fe Irradiation on the Hematopoietic System in Trp53-Heterozygous Mice.
2020Co-Authors: Tanaka Kaoru, Wang Ing, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qiang, Nakajima TetsuoAbstract:Both ionizing radiation (IR) and psychological stresses (PS) cause detrimental effects on humans. A pioneering study showed chronic restraint-induced PS (CRIPS) increased gamma-radiation-induced carcinogenesis in Trp53+/- mice. Prior to carcinogenesis study, to investigate the effects from PS on IR-induced health consequences, effects of Fe total body irradiation (Fe TBI) on the Hematopoietic System in Trp53+/- mice under CRIPS were studied. Six-week-old male C57BL/6N mice were chronically restrained 6 hours daily for consecutive 28 days, being given Fe TBI (0.1 Gy or 2.0 Gy) on the 8th day. The peripheral blood and the bone marrow were collected for analysis of hematological abnormality and residual damage in the erythrocytes. Results showed that concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy. This work was partially supported by MEXT Grant-in-Aid for Scientific Research on Innovative Areas, “Living in Space” (JP15K21745, 15H05944 and 5H05935).日本宇宙生物科学会第33回大会
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Effects from Chronic Restraint-Induced Stress and Total Body Fe Irradiation on the Hematopoietic System in Trp53-Heterozygous Mice
2019Co-Authors: Wang Ing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qiang, Nakajima TetsuoAbstract:Both ionizing radiation (IR) and psychological stresses (PS) cause detrimental effects on humans. There is a great concern to understand if PS could cause any alterations in the response of human beings to IR. A pioneering study showed chronic restraint-induced PS (CRIPS) increased gamma-radiation-induced carcinogenesis in Trp53+/- mice. Prior to carcinogenesis study, to investigate the effects from PS on IR-induced health consequences, effects of Fe total body irradiation (Fe TBI) on the Hematopoietic System in Trp53+/- mice under CRIPS were studied. Six-week-old male C57BL/6N mice were chronically restrained 6 hours daily for consecutive 28 days, being given Fe TBI (0.1 Gy or 2.0 Gy) on the 8th day. The peripheral blood and the bone marrow were collected for analysis of hematological abnormality and residual damage in the erythrocytes. Results showed that CRIPS alone hardly induce marked alteration in hematological parameters in the peripheral blood and the formation of micronucleated erythrocytes in the bone marrow while Fe TBI alone could induce significant hematological alteration and increased micronucleated erythrocytes. On the other hand, concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy.新領域学術研究「宇宙に生きる」2018年度第2回全体会
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Effects from chronic restraint-induced stress and total body Fe irradiation on the Hematopoietic System in Trp53-heterozygous mice.
2019Co-Authors: Wang Ing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qing, Nakajima TetsuoAbstract:Exposure to either ionizing radiation or psychological stress (PS) could cause detrimental effects on humans. The RBE of high atomic number and energy particles such as Fe ions from the galactic cosmic rays and solar particle events is usually higher than low LET gamma or X-rays. A pioneering study showed that chronic restraint-induced PS (CRIPS) could attenuate Trp53 functions and increase carcinogenesis induced by low LET gamma-rays in Trp53-heterozygous (Trp53+/-) mice.Prior to a carcinogenesis study, we further investigated the modification effects from CRIPS on radiation-induced deterministic effects in the Hematopoietic System in a mouse CRIPS model. We reported previously that in Trp53 wild type (Trp53wt) animals receiving total body irradiation (TBI) with low LET X-rays, CRIPS did not have a significant impact on radiation-induced detrimental effects.In this work, Trp53+/- mice were given both CRIPS and accelerated Fe ions. Results showed that CRIPS alone hardly induce marked alteration in hematological parameters in the peripheral blood and the formation of micronucleated erythrocytes in the bone marrow while Fe TBI alone could induce significant hematological alteration and increased micronucleated erythrocytes. On the other hand, concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy. These findings suggest that concurrent exposure to CRIPS and high LET Fe, particularly at low doses, may have a significant impact on radiation-induced detrimental effects on the Hematopoietic System in Trp53+/- mice. At this annual meeting, the details of the results will be introduced.This work was partially supported by both the Ministry of Education, Culture, Sports, Science and Technology Grant-in-Aid for Scientific Research on Innovative Areas, Grant Numbers JP15K21745 and 15H05935 “Living in Space” and 3 HIMAC Research Project Grants (22B258, 14J286 and 16J295). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.The 64th Annual Radiation Research Society MeetingRRS 2018 学会参加して 「Effects from chronic restraint-induced stress and total body Fe irradiation on the Hematopoietic System in Trp53-heterozygous mice.」のタイトルで ポスター発表を行う
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Induction of genotoxicity by accelerated heavy iron particles in the Hematopoietic System in mice.
2019Co-Authors: Wang Bing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Nakajima Tetsuo, Fujimori AkiraAbstract:Purpose: The genotoxicity induced by high LET iron particles was studied and compared to that by low LET X-rays in the ground-based experiments carried out at NIRS using total body irradiation (TBI) of mice with the Heavy Ion Medical Accelerator in Chiba (HIMAC) and an X-ray generator (Pantak 320S, Shimadzu).Materials and Methods: C57BL/6J Jms strain female mice of 8 weeks old were used. TBI was performed at a dose ranging from 0.1 to 3.0 Gy for iron particles (500 MeV/nucleon, 200 keV/μm), or from 0.1 to 5.0 Gy for X-rays (200 kVp, 0.5 mm Al + 0.5 mm Cu filter). The RBE of iron particles to X-rays for induction of acute genotoxicity and late residual damage in the Hematopoietic System was determined respectively at one and two months after TBI using the frequency of micronuclei in bone marrow erythrocytes as the endpoint. The health condition (body weight gain and the hemogram of the peripheral blood) was also investigated. Animals were treated in accordance with the Guidelines for the Care and Use of Laboratory Animals established by NIRS.Results and Conclusions: Reduction of body weight gain after TBI was in a similar way observed in the groups exposed to high doses from iron particles or X-rays. X-rays caused more efficiently hematological abnormality than iron particles. Iron particles and X-rays reduced the ratio of polychromatic erythrocytes (PCEs) to PCEs plus normochromatic erythrocytes (NCEs), an indicator for bone marrow proliferation, in a similar way, while iron particles resulted in more efficiently micronucleated PCEs and NCEs at low doses than X-rays. The relative effectiveness of iron particles to X-rays for induction of genotoxicity in bone marrow erythrocytes was higher at a low dose (0.5 Gy) than that at a high dose (3.0 Gy).Acknowledgments: This work was partially supported by both the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Grant-in-Aid for Scientific Research on Innovative Areas, Grant Number 15H05935 “Living in Space” and three HIMAC Research Project Grants (22B258, 14J286 and 16J295). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.COSPAR 2018 （42nd Assembly, 60th Anniversary
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Relative Effectiveness of Heavy Ion Irradiations from Accelerated Iron-56 Particles for Induction of Genotoxicity in the Hematopoietic System in Mice: Hematological Abnormality in the Peripheral Blood and Residual Damage in the Bone Marrow Erythrocyt
2019Co-Authors: Wang Bing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Nakajima Tetsuo, Nagamatsu AikoAbstract:Purpose: To comparatively study the genotoxicity induced by high LET HZE Fe particles to that by low LET X-rays, ground-based experiments were carried out at the National Institute of Radiological Sciences (NIRS) using total body irradiation (TBI) of mice with accelerated Fe particles generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC) and an X-ray generator (Pantak 320S, Shimadzu).Materials and Methods: C57BL/6J Jms strain female mice of 8 weeks old were used in the study. Animals were treated in accordance with the Guidelines for the Care and Use of Laboratory Animals established by NIRS. TBI was performed at a dose ranging from 0.1 to 3.0 Gy for Fe particles (500 MeV/nucleon, 200 keV/μm), or from 0.1 to 5.0 Gy for X-rays (200 kVp, 0.5 mm Al + 0.5 mm Cu filter). The RBE of Fe particles to X-rays for induction of acute genotoxicity and late residual damage in the Hematopoietic System was determined respectively at one and two months after TBI using the frequency of micronuclei in bone marrow erythrocytes as the endpoint. The health condition (body weight gain and the hemogram of the peripheral blood) was also investigated.Results and Conclusions: Reduction in a similar way of the body weight gain was observed in the groups exposed to TBI at high doses from Fe particles or X-rays. X-rays caused more efficiently hematological abnormality than Fe particles. Fe particles and X-rays reduced the ratio of polychromatic erythrocytes (PCEs) to PCEs plus normochromatic erythrocytes (NCEs), an indicator for bone marrow proliferation, in a similar way, while Fe particles resulted in more efficiently micronucleated PCEs and NCEs at low doses than X-rays. The relative effectiveness of Fe particles to X-rays for induction of genotoxicity in erythrocytes was higher at a low dose (0.5 Gy) than that at a high dose (3.0 Gy).Acknowledgments: This work was partially supported by both the Ministry of Education, Culture, Sports, and Science Culture Grant-in-Aid for Scientific Research on Innovative Areas, Grant Number 15H05935 “Living in Space” and two HIMAC Research Project Grants (22B258 and 14J286). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.2017.RRS (63rd Annual International Meeting, Radiation Research Society)に参加して発表を行
J. Wdzieczak-bakala - One of the best experts on this subject based on the ideXlab platform.
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Formation of acetyl-Ser-Asp-Lys-Pro, a new regulator of the Hematopoietic System, through enzymatic processing of thymosin beta 4.
Annals of the New York Academy of Sciences, 1991Co-Authors: M Lenfant, Catherine Grillon, J. Rieger, D Sotty, J. Wdzieczak-bakalaAbstract:The demonstration that AcSDKP, a new regulator of the Hematopoietic System, is formed in the bone marrow by a one-step enzymatic maturation processing of thymosin beta 4 (T beta 4) is presented. AcSDKP and T beta 4 were both detected in bone marrow cells (BMC). Incubation of [3H]T beta 4 with either intact or lysed BMC led to the formation of [3H]AcSDKP, whereas the labeled tetrapeptide was not degraded under these conditions. Model enzymatic degradation of T beta 4 carried out with bacterial enzymes suggests that a mammalian endoproteinase Asp-N might be involved in the formation of AcSDKP through the specific cleavage of the Pro4-Asp5 peptidic bond of T beta 4. In contrast, alpha-prolyl-endopeptidase was ineffective in carrying out a similar processing.
M Lenfant - One of the best experts on this subject based on the ideXlab platform.
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Formation of acetyl-Ser-Asp-Lys-Pro, a new regulator of the Hematopoietic System, through enzymatic processing of thymosin beta 4.
Annals of the New York Academy of Sciences, 1991Co-Authors: M Lenfant, Catherine Grillon, J. Rieger, D Sotty, J. Wdzieczak-bakalaAbstract:The demonstration that AcSDKP, a new regulator of the Hematopoietic System, is formed in the bone marrow by a one-step enzymatic maturation processing of thymosin beta 4 (T beta 4) is presented. AcSDKP and T beta 4 were both detected in bone marrow cells (BMC). Incubation of [3H]T beta 4 with either intact or lysed BMC led to the formation of [3H]AcSDKP, whereas the labeled tetrapeptide was not degraded under these conditions. Model enzymatic degradation of T beta 4 carried out with bacterial enzymes suggests that a mammalian endoproteinase Asp-N might be involved in the formation of AcSDKP through the specific cleavage of the Pro4-Asp5 peptidic bond of T beta 4. In contrast, alpha-prolyl-endopeptidase was ineffective in carrying out a similar processing.
Derrick J Rossi - One of the best experts on this subject based on the ideXlab platform.
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perturbation of the Hematopoietic System during embryonic liver development due to disruption of polyubiquitin gene ubc in mice
PLOS ONE, 2012Co-Authors: Kwonyul Ryu, Irving L Weissman, Derrick J Rossi, Hyejin Park, Ron R KopitoAbstract:Disruption of the polyubiquitin gene Ubc leads to a defect in fetal liver development, which can be partially rescued by increasing the amount of ubiquitin. However, it is still not known why Ubc is required for fetal liver development and the nature of the defective cell types responsible for embryonic lethality have not been characterized. In this study, we assessed the cause of embryonic lethality with respect to the fetal liver Hematopoietic System. We found that Ubc was highly expressed in the embryonic liver, and the proliferation capacity of fetal liver cells was reduced in Ubc−/− embryos. Specifically, Ubc was most highly expressed in Hematopoietic cells, and the proliferation capacity of Hematopoietic cells was significantly impaired in Ubc−/− embryos. While Hematopoietic cell and Hematopoietic stem cell (HSC) frequency was maintained in Ubc−/− embryos, the absolute number of these cells was diminished because of reduced total liver cell number in Ubc−/− embryos. Transplantations of fetal liver cells into lethally irradiated recipient mice by non-competitive and competitive reconstitution methods indicated that disruption of Ubc does not significantly impair the intrinsic function of fetal liver HSCs. These findings suggest that disruption of Ubc reduces the absolute number of HSCs in embryonic livers, but has no significant effect on the autonomous function of HSCs. Thus, the lethality of Ubc−/− embryos is not the result of intrinsic HSC failure.
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stem cells and the aging Hematopoietic System
Current Opinion in Immunology, 2010Co-Authors: Isabel Beerman, William J Maloney, Irving L Weissmann, Derrick J RossiAbstract:Advancing age is accompanied by a number of clinically significant conditions arising in the Hematopoietic System that include: diminution and decreased competence of the adaptive immune System, elevated incidence of certain autoimmune diseases, increased hematological malignancies, and elevated incidence of age-associated anemia. As with most tissues, the aged Hematopoietic System also exhibits a reduced capacity to regenerate and return to normal homeostasis after injury or stress. Evidence suggests age-dependent functional alterations within the Hematopoietic stem cell compartment significantly contribute to many of these pathophysiologies. Recent developments have shed light on how aging of the Hematopoietic stem cell compartment contributes to Hematopoietic decline through diverse mechanisms.
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stem cells and aging in the Hematopoietic System
Mechanisms of Ageing and Development, 2009Co-Authors: Luigi Warren, Derrick J RossiAbstract:Abstract The effector cells of the blood have limited lifetimes and must be replenished continuously throughout life from a small reserve of Hematopoietic stem cells (HSCs) in the bone marrow. Although serial bone marrow transplantation experiments in mice suggest that the replicative potential of HSCs is finite, there is little evidence that replicative senescence causes depletion of the stem cell pool during the normal lifespan of either mouse or man. Studies conducted in murine genetic models defective in DNA repair, intracellular ROS management, and telomere maintenance indicate that all these pathways are critical to the longevity and stress response of the stem cell pool. With age, HSCs show an increased propensity to differentiate towards myeloid rather than lymphoid lineages, which may contribute to the decline in lymphopoiesis that attends aging. Challenges for the future include assessing the significance of ‘lineage skewing’ to immune dysfunction, and investigating the role of epigenetic dysregulation in HSC aging.
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Hematopoietic stem cells and the aging Hematopoietic System
Seminars in Hematology, 2008Co-Authors: Roi Gazit, Irving L Weissman, Derrick J RossiAbstract:The etiology of the age-associated pathophysiological changes of the Hematopoietic System including the onset of anemia, diminished adaptive immune competence, and myelogenous disease development are underwritten by the loss of normal homeostatic control. As tissue and organ homeostasis in adults is primarily mediated by the activity of stem and progenitor cells, it has been suggested that the imbalances accompanying aging of the Hematopoietic System may stem from alterations in the prevalence and/or functional capacity of Hematopoietic stem cells (HSCs) and progenitors. In this review, we examine evidence implicating a role for stem cells in the aging of the Hematopoietic System, and focus on the mechanisms suggested to contribute to stem cell aging.
Tanaka Kaoru - One of the best experts on this subject based on the ideXlab platform.
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Effects from Chronic Restraint-Induced Stress and Total Body Fe Irradiation on the Hematopoietic System in Trp53-Heterozygous Mice.
2020Co-Authors: Tanaka Kaoru, Wang Ing, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qiang, Nakajima TetsuoAbstract:Both ionizing radiation (IR) and psychological stresses (PS) cause detrimental effects on humans. A pioneering study showed chronic restraint-induced PS (CRIPS) increased gamma-radiation-induced carcinogenesis in Trp53+/- mice. Prior to carcinogenesis study, to investigate the effects from PS on IR-induced health consequences, effects of Fe total body irradiation (Fe TBI) on the Hematopoietic System in Trp53+/- mice under CRIPS were studied. Six-week-old male C57BL/6N mice were chronically restrained 6 hours daily for consecutive 28 days, being given Fe TBI (0.1 Gy or 2.0 Gy) on the 8th day. The peripheral blood and the bone marrow were collected for analysis of hematological abnormality and residual damage in the erythrocytes. Results showed that concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy. This work was partially supported by MEXT Grant-in-Aid for Scientific Research on Innovative Areas, “Living in Space” (JP15K21745, 15H05944 and 5H05935).日本宇宙生物科学会第33回大会
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Effects from Chronic Restraint-Induced Stress and Total Body Fe Irradiation on the Hematopoietic System in Trp53-Heterozygous Mice
2019Co-Authors: Wang Ing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qiang, Nakajima TetsuoAbstract:Both ionizing radiation (IR) and psychological stresses (PS) cause detrimental effects on humans. There is a great concern to understand if PS could cause any alterations in the response of human beings to IR. A pioneering study showed chronic restraint-induced PS (CRIPS) increased gamma-radiation-induced carcinogenesis in Trp53+/- mice. Prior to carcinogenesis study, to investigate the effects from PS on IR-induced health consequences, effects of Fe total body irradiation (Fe TBI) on the Hematopoietic System in Trp53+/- mice under CRIPS were studied. Six-week-old male C57BL/6N mice were chronically restrained 6 hours daily for consecutive 28 days, being given Fe TBI (0.1 Gy or 2.0 Gy) on the 8th day. The peripheral blood and the bone marrow were collected for analysis of hematological abnormality and residual damage in the erythrocytes. Results showed that CRIPS alone hardly induce marked alteration in hematological parameters in the peripheral blood and the formation of micronucleated erythrocytes in the bone marrow while Fe TBI alone could induce significant hematological alteration and increased micronucleated erythrocytes. On the other hand, concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy.新領域学術研究「宇宙に生きる」2018年度第2回全体会
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Effects from chronic restraint-induced stress and total body Fe irradiation on the Hematopoietic System in Trp53-heterozygous mice.
2019Co-Authors: Wang Ing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Liu Qing, Nakajima TetsuoAbstract:Exposure to either ionizing radiation or psychological stress (PS) could cause detrimental effects on humans. The RBE of high atomic number and energy particles such as Fe ions from the galactic cosmic rays and solar particle events is usually higher than low LET gamma or X-rays. A pioneering study showed that chronic restraint-induced PS (CRIPS) could attenuate Trp53 functions and increase carcinogenesis induced by low LET gamma-rays in Trp53-heterozygous (Trp53+/-) mice.Prior to a carcinogenesis study, we further investigated the modification effects from CRIPS on radiation-induced deterministic effects in the Hematopoietic System in a mouse CRIPS model. We reported previously that in Trp53 wild type (Trp53wt) animals receiving total body irradiation (TBI) with low LET X-rays, CRIPS did not have a significant impact on radiation-induced detrimental effects.In this work, Trp53+/- mice were given both CRIPS and accelerated Fe ions. Results showed that CRIPS alone hardly induce marked alteration in hematological parameters in the peripheral blood and the formation of micronucleated erythrocytes in the bone marrow while Fe TBI alone could induce significant hematological alteration and increased micronucleated erythrocytes. On the other hand, concurrent exposure of the animals to CRIPS and Fe TBI always showed a tendency of increased micronucleated erythrocytes when compared to the animals receiving only Fe TBI, and the increase was statistically significant for the mice receiving Fe TBI at 0.1 Gy. These findings suggest that concurrent exposure to CRIPS and high LET Fe, particularly at low doses, may have a significant impact on radiation-induced detrimental effects on the Hematopoietic System in Trp53+/- mice. At this annual meeting, the details of the results will be introduced.This work was partially supported by both the Ministry of Education, Culture, Sports, Science and Technology Grant-in-Aid for Scientific Research on Innovative Areas, Grant Numbers JP15K21745 and 15H05935 “Living in Space” and 3 HIMAC Research Project Grants (22B258, 14J286 and 16J295). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.The 64th Annual Radiation Research Society MeetingRRS 2018 学会参加して 「Effects from chronic restraint-induced stress and total body Fe irradiation on the Hematopoietic System in Trp53-heterozygous mice.」のタイトルで ポスター発表を行う
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Induction of genotoxicity by accelerated heavy iron particles in the Hematopoietic System in mice.
2019Co-Authors: Wang Bing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Nakajima Tetsuo, Fujimori AkiraAbstract:Purpose: The genotoxicity induced by high LET iron particles was studied and compared to that by low LET X-rays in the ground-based experiments carried out at NIRS using total body irradiation (TBI) of mice with the Heavy Ion Medical Accelerator in Chiba (HIMAC) and an X-ray generator (Pantak 320S, Shimadzu).Materials and Methods: C57BL/6J Jms strain female mice of 8 weeks old were used. TBI was performed at a dose ranging from 0.1 to 3.0 Gy for iron particles (500 MeV/nucleon, 200 keV/μm), or from 0.1 to 5.0 Gy for X-rays (200 kVp, 0.5 mm Al + 0.5 mm Cu filter). The RBE of iron particles to X-rays for induction of acute genotoxicity and late residual damage in the Hematopoietic System was determined respectively at one and two months after TBI using the frequency of micronuclei in bone marrow erythrocytes as the endpoint. The health condition (body weight gain and the hemogram of the peripheral blood) was also investigated. Animals were treated in accordance with the Guidelines for the Care and Use of Laboratory Animals established by NIRS.Results and Conclusions: Reduction of body weight gain after TBI was in a similar way observed in the groups exposed to high doses from iron particles or X-rays. X-rays caused more efficiently hematological abnormality than iron particles. Iron particles and X-rays reduced the ratio of polychromatic erythrocytes (PCEs) to PCEs plus normochromatic erythrocytes (NCEs), an indicator for bone marrow proliferation, in a similar way, while iron particles resulted in more efficiently micronucleated PCEs and NCEs at low doses than X-rays. The relative effectiveness of iron particles to X-rays for induction of genotoxicity in bone marrow erythrocytes was higher at a low dose (0.5 Gy) than that at a high dose (3.0 Gy).Acknowledgments: This work was partially supported by both the Ministry of Education, Culture, Sports, Science and Technology (MEXT) Grant-in-Aid for Scientific Research on Innovative Areas, Grant Number 15H05935 “Living in Space” and three HIMAC Research Project Grants (22B258, 14J286 and 16J295). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.COSPAR 2018 （42nd Assembly, 60th Anniversary
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Relative Effectiveness of Heavy Ion Irradiations from Accelerated Iron-56 Particles for Induction of Genotoxicity in the Hematopoietic System in Mice: Hematological Abnormality in the Peripheral Blood and Residual Damage in the Bone Marrow Erythrocyt
2019Co-Authors: Wang Bing, Tanaka Kaoru, Katsube Takanori, Ninomiya Yasuharu, Hirakawa Hirokazu, Liu Cuihua, Maruyama Kouichi, Vares Guillaume, Nakajima Tetsuo, Nagamatsu AikoAbstract:Purpose: To comparatively study the genotoxicity induced by high LET HZE Fe particles to that by low LET X-rays, ground-based experiments were carried out at the National Institute of Radiological Sciences (NIRS) using total body irradiation (TBI) of mice with accelerated Fe particles generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC) and an X-ray generator (Pantak 320S, Shimadzu).Materials and Methods: C57BL/6J Jms strain female mice of 8 weeks old were used in the study. Animals were treated in accordance with the Guidelines for the Care and Use of Laboratory Animals established by NIRS. TBI was performed at a dose ranging from 0.1 to 3.0 Gy for Fe particles (500 MeV/nucleon, 200 keV/μm), or from 0.1 to 5.0 Gy for X-rays (200 kVp, 0.5 mm Al + 0.5 mm Cu filter). The RBE of Fe particles to X-rays for induction of acute genotoxicity and late residual damage in the Hematopoietic System was determined respectively at one and two months after TBI using the frequency of micronuclei in bone marrow erythrocytes as the endpoint. The health condition (body weight gain and the hemogram of the peripheral blood) was also investigated.Results and Conclusions: Reduction in a similar way of the body weight gain was observed in the groups exposed to TBI at high doses from Fe particles or X-rays. X-rays caused more efficiently hematological abnormality than Fe particles. Fe particles and X-rays reduced the ratio of polychromatic erythrocytes (PCEs) to PCEs plus normochromatic erythrocytes (NCEs), an indicator for bone marrow proliferation, in a similar way, while Fe particles resulted in more efficiently micronucleated PCEs and NCEs at low doses than X-rays. The relative effectiveness of Fe particles to X-rays for induction of genotoxicity in erythrocytes was higher at a low dose (0.5 Gy) than that at a high dose (3.0 Gy).Acknowledgments: This work was partially supported by both the Ministry of Education, Culture, Sports, and Science Culture Grant-in-Aid for Scientific Research on Innovative Areas, Grant Number 15H05935 “Living in Space” and two HIMAC Research Project Grants (22B258 and 14J286). The expert technical assistance and administrative support of Ms. Hiromi Arai, Mr. Sadao Hirobe, Ms. Mikiko Nakajima, and Ms. Yasuko Morimoto are gratefully acknowledged.2017.RRS (63rd Annual International Meeting, Radiation Research Society)に参加して発表を行