2020 Fiscal Year Final Research Report
Inflammation from low dose irradiation in Medaka
| Project/Area Number |
18H04135
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Review Section |
Medium-sized Section 63:Environmental analyses and evaluation and related fields
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
Mitani Hiroshi 東京大学, 大学院新領域創成科学研究科, 教授 (70181922)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
尾田 正二 東京大学, 大学院新領域創成科学研究科, 准教授 (50266714)
小賀 厚徳 山口大学, 大学院医学系研究科, 准教授 (90243633)
|
|---|
| Project Period (FY) |
2018-04-01 – 2021-03-31
|
| Keywords | 放射線 / 炎症 / 遺伝子 / メダカ / 精巣卵 / 腎臓 / 好中球 |
|---|
| Outline of Final Research Achievements |
Wild-type medaka was irradiated with a total dose of 100 mGy gamma rays over seven days. At seven days after irradiation, the pathological examination of each organ was performed in serial tissue sections of the whole body. A decrease in the number of type B spermatogonial cells and a reduction in the proliferation of gill epithelium were observed. Transcriptome analysis showed that the expression of genes related to glycolytic and pentose phosphate pathways was suppressed. The production of NADPH, which plays an important role in antioxidation, was enhanced. The swimming behaviors during the irradiation were videotaped and quantified. The swimming activity of the irradiated fish was enhanced at 5 and 6 days of irradiation period. Chlorella feeding reduced the expression of cytokines and inflammatory mediator genes that promote neutrophil activity and mobilization and macrophage activity associated with inflammatory responses.
|
| Free Research Field |
放射線生物学
|
| Academic Significance and Societal Importance of the Research Achievements |
慢性的な炎症状態の持続は様々な疾患の原因となることが近年急速に明らかになっているが、軽微な炎症反応は自然と治癒・沈静化するためにこれまで大きな注意を払われてこなかった。低線量率長期被ばくが脊椎動物（メダカ）の体のハード（組織構築）とソフト（行動と遺伝子発現パターン）に与えるインパクトを網羅したデータを収集し、RNA-Seq解析とマクロファージと好中球の動態と精巣卵形成が低線量率長期被ばくの生物影響評価に有効な指標となることが明らかにされた。照射下での遊泳行動には、変化が認められたので、再現性と線量依存性の確認が必要である。また、未成熟期での亞致死線量照射に発癌抑制効果があることを示した。
|
