Transgenic fluorescent zebrafish as tools to characterize prostaglandin EP4 receptor gene expression and to discover drug candidates for abdominal aorta aneurysm

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K17730
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55030:Cardiovascular surgery-related
• Research Institution: Tokyo Medical University
• Principal Investigator: TANIFUJI Shota 東京医科大学, 医学部, 助教 (50529245)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ゼブラフィッシュ / EP4 / 腹部大動脈瘤 / アンジオテンシンII

Outline of Final Research Achievements

The PGE receptor EP4 is distributed in various cells to maintain homeostasis. In abdominal aortic aneurysms (AAA), excessive EP4 expression has been implicated in the progression of the disease, but the mechanism of excessive EP4 expression is unknown. In this study, we aimed to elucidate the molecular mechanism of EP4 expression and to search for compounds that inhibit EP4 expression as a new treatment for AAA. We generated transgenic zebrafish in which EP4 gene expression could be visualized in vivo, and EGFP expression was confirmed. In addition, administration of angiotensin II(AngII) to transgenic zebrafish with visualized blood vessels resulted in a 1.2-fold increase in the dorsal aortic diameter compared to buffer-injected controls at 5 days post-fertilization. AngII-injected 2-month-old zebrafish did not show evidence of aortic expansion, but elastic fiber formation was partly attenuated with enhanced matrix metalloproteinase-2 expression.

Free Research Field

循環生理学

Academic Significance and Societal Importance of the Research Achievements

本研究で作製したEP4-EGFPレポーターゼブラフィッシュは、現時点で唯一EP4発現をin vivoで可視化でき、時間依存的な定量が可能となった遺伝子改変ゼブラフィッシュである。In vivo解析により、生体内環境でEP4発現の亢進をもたらす機序が明らかになれば、AAA等の過剰なEP4シグナルが関与する疾患の病態の理解に貢献ができると期待される。加えてAngII投与ゼブラフィッシュは、稚魚での大動脈径の増大を指標とすることで、治療薬候補となる化合物を短期間にin vivoで絞り込むことが可能であるため、現在までに根本的治療法のないAAAに対する新規の治療法開発への貢献度は高いと考えられる。