Clarification of the mechanism for Japanese paradox regarding ischemic heart disease by using microRNA

2020 Fiscal Year Final Research Report

• Project/Area Number: 17H02184
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Applied health science
• Research Institution: Hyogo Medical University
• Principal Investigator: Ichiro Wakabayashi 兵庫医科大学, 医学部, 教授 (70220829)
• Co-Investigator(Kenkyū-buntansha): 江口 良二 兵庫医科大学, 医学部, 助教 (00461088) ; 大門 貴志 兵庫医科大学, 医学部, 教授 (40372156)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: マイクロRNA / 虚血性心疾患 / 人種差 / 血管平滑筋細胞 / 血小板 / 赤血球

Outline of Final Research Achievements

The mortality from ischemic heart disease is much lower in Japan than in Western countries. In order to elucidate the reason for this difference, expression levels of microRNAs in the blood were totally analyzed and compared in Austrians and Japanese. The levels of 372 miRNAs showed significant difference between the countries, and the targeting molecules of these miRNAs were suggested to be collagen in vascular smooth muscle cells and IL-1, IL-6, IL-8, TNF, MMP-3 and MMP-9 in foam cells. There were 12 miRNAs that showed significant difference in their expression levels in the blood of Austrian and Japanese men and were reported to be associated with ischemic heart disease.

Free Research Field

衛生学

Academic Significance and Societal Importance of the Research Achievements

日本では欧米に比べて心筋梗塞などの虚血性心疾患の死亡率が低いが、その理由は不明である。そこで、蛋白質の転写発現を調節するマイクロRNA (miRNA)の違いを検討した。日本人とオーストリア人の血中のすべてのマイクロRNAレベルを調べたところ、372種類のmiRNAに差が認められ、これらのmiRNAは動脈硬化の進行に関連する動脈壁の複数の蛋白の発現を調節していることが判明した。日本人で虚血性心疾患が少ない理由にmiRNAが関係している可能性を、本研究は世界で初めて示唆した。