Elucidation of mechanism between delayed ROS and extra-nuclear signal involved in radiation effects

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K07736
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Nara Medical University
• Principal Investigator: Kashino GENRO 奈良県立医科大学, 医学部, 准教授 (00437287)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 活性酸素 / ATM / p53 / 細胞老化 / 放射線

Outline of Final Research Achievements

We investigated how delayed reactive oxygen species after radiation exposure are involved in the DNA damage response in the nucleus. First, when only the outside of the nucleus was irradiated with an X-ray microbeam, a decrease in survival rate was observed with 3 Gy irradiation, but even when delayed reactive oxygen species were relieved, the survival rate was not different from that of the untreated control. When the whole cell was irradiated, an increase in survival rate was observed with AA2G, suggesting that delayed reactive oxygen species play a role in auxiliary amplification of signals originating from DNA damage after hitting the nucleus. It was found that delayed reactive oxygen species play a role in maintaining the ATM-p53 signal in the nucleus even after 3 days from irradiation, and contribute to the induction of cell death and senescence.

Free Research Field

放射線生物学

Academic Significance and Societal Importance of the Research Achievements

放射線障害を引き起こす細胞内の機構の一部を解明することができた。この研究により、放射線障害を抑制する方法の探索が前進するものと期待される。特にアスコルビン酸のような抗酸化剤は放射線障害を抑制する上で役立つが、その処理は照射前からでなく、照射後からでも効果が期待される可能性が高いことが分かった。さらに新たな放射線防護剤の開発においても、今回明らかにした機構が指標として使える可能性が高い。