Development of protection method against low dose rate radiation exposure of hematopoietic system

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K00552
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Risk sciences of radiation and chemicals
• Research Institution: Fukuoka University (2019); Hiroshima University (2017-2018)
• Principal Investigator: Ohio Yoshinori 福岡大学, 医学部, 講師 (10548986)
• Co-Investigator(Kenkyū-buntansha): 安永 晋一郎 福岡大学, 医学部, 教授 (50336111)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 低線量率放射線 / 造血幹細胞 / ミトコンドリア / ROS

Outline of Final Research Achievements

Hematopoietic tissues are highly sensitive to radiation and prone to radiation injury. It is feared that hematopoietic failure develops and, as a result of the later effects, hematopoietic abnormalities such as leukemia could be induced. We have analyzed effects of low dose-rate radiation exposure on hematopoietic tissues, that have largely remained elusive, and aimed to contribute for establishing a basic theory for preventing the adverse effects of low dose-rate exposure. We found that low dose-rate radiation exposure specifically decreased the number and activity of immature hematopoietic cells including hematopoietic stem cells. Furthermore, it was clarified that the cause was ROS produced from mitochondria. And we found that a new protection method targeting mitochondria is effective.

Free Research Field

幹細胞生物学

Academic Significance and Societal Importance of the Research Achievements

本研究では、今まで充分には明らかにされて来なかった低線量率放射線被ばくの造血システムへの影響について細胞レベルから分子レベルまで詳細に解析した。さらに、その低線量率放射線の影響を軽減されることができる新たな防護法を見出した。原発作業や宇宙開発などの環境下では、長期間に渡る低線量率放射線被ばくが生ずることが危惧され、本研究で明らかにしたように造血幹細胞の特異的な減少や機能障害によって造血不全や免疫不全が引き起こされる危険性が考えられる。そして、本研究成果によって、新たな防御法の開発に道が開かれることを期待したい。