Analysis of the gene cross talk within a brain of photoaging and learning ability depression by long-term UV eye irradiation

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K11085
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 59040:Nutrition science and health science-related
• Research Institution: Suzuka University of Medical Science
• Principal Investigator: Hiramoto Keiichi 鈴鹿医療科学大学, 薬学部, 助教 (90251793)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: UVA / 光老化 / 記憶・学習能力 / 慢性炎症

Outline of Final Research Achievements

Long-term eye exposure to UVA can effect memory and learning ability. However, the underlying mechanism behind these effects remain unknown. In this study, we used mice to study effects of long-term UVA eye irradiation. The eyes of the mice were exposed to UVA at the dose of 110kj/m2 using an FL20SBLB-A lamp three times a week over 12 months. Our results showed that UVA eye irradiation potentially mediated a decline in memory and learning ability via enhancing levels of urocortin 2, microglia, and β-amyloid in the brain. In addition, we found that the p53 level increased significantly following long-term UVA eye irradiation, whereas the levels of Period2, Bmal1, Clock, NMNAT and NAMPT activities, NAD+ , and Sirt1 decreased significantly.
These results indicate that it was shown that UVA eye irradiation leads to aging of the whole body by controlling the hormonal system, the inflammatory system and the clock gene system.

Free Research Field

光生物学

Academic Significance and Societal Importance of the Research Achievements

UVA長期眼照射による光老化の誘導は申請者が発見した新規領域で極めて独創的であり、現在大きな問題になっている紫外線による病態の予防軽減法開発に有効であり、その意義は極めて大きい。
さらに本研究結果は、UVA長期眼照射による光老化と時計遺伝子の関係に言及した報告であり、現在社会における生活習慣の乱れ（夜更かしや昼夜逆転）による様々な肉体的および精神的疾患と光老化を結びつける重要な研究である。