統合ストレス反応カップル 酸化ストレス制御によるミトコンドリアタンパク質翻訳
Guangyu Zhang1, Xiaoding Wang1, Chao Li1
1Division of Cardiology (G.Z., X.W., C.L., Q.L., X.L., T.G.G., Z.V.W.), Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas.
Circulation
|September 29, 2021
まとめ
統合ストレス反応 (ISR) は,心筋梗塞後の再注血損傷中に心臓を保護します. ISRを活性化すると,ミトコンドリアのタンパク質合成と酸化ストレスが抑制され,心臓の損傷が軽減されます.
科学分野:
- 心臓病科
- 分子生物学
- 細胞 の ストレス 反応
背景:
- 心筋梗塞は 世界的に主要な死因です
- 冠動脈再注血は,命を救う一方で,心臓のさらなる損傷 (再注血損傷) を引き起こす可能性があります.
- 統合ストレス反応 (ISR) は,干渉に反応する細胞メカニズムです.
研究 の 目的:
- 心筋不全/再注血 (I/R) 損傷におけるISRの役割を調査する.
- 心筋梗塞の治療のためにISRを操作する治療の可能性を探求する.
主な方法:
- 心臓特有の機能増減モデルを in vivo で利用した.
- 冠動脈の結合と再循環によって誘発された心筋内出出血
- 細胞培養と組織における分子メカニズムを分析した.
- ISRタンパク質の標的を特定し,薬理学的介入を試験した.
主要な成果:
- ISRのPERK (PKRのような内 плазма網膜内定キナーゼ) /eIF2α (エウカリオット開始因子2のα亜単位) 軸は,I/Rによって有意に誘発された.
- 心臓のPERK/ eIF2αシグナリングの活性化により,再注血による損傷に対する心臓保護が認められた.
- PERKは,ミトコンドリア複合体Iの組立因子であるNDUFAF2 (NADH:ウビキノン酸化還元酵素複合体組立因子2) を標的とし,その発現を抑制する.
- ISRの活性化により,ミトコンドリアの活性酸素種が減少し,心臓細胞の生存率が向上した.
結論:
- ISRは心臓細胞の生存率を高め,再注血による損傷を軽減します.
- この保護は,ミトコンドリアのタンパク質合成を選択的に抑制し,酸化ストレスを軽減することによって達成されます.
- ISRの薬理学的活性化は,心筋梗塞の治療に臨床的関連性を示しています.
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