アポプトティック・ストレスは,老化中のmtDNAの放出を引き起こし,SASPを駆動する
Stella Victorelli1,2, Hanna Salmonowicz1,2,3,4, James Chapman3
1Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
Nature
|October 11, 2023
まとめ
細胞老化は,老化に関連した分泌現象型 (SASP) を介して,年齢に関連する機能障害を誘発する. 衰老細胞におけるミトコンドリア外膜浸透 (MOMP) を阻害すると,炎症が軽減され,マウスの健康期間が延長されます.
科学分野:
- 細胞生物学
- 老化に関する研究
- ミトコンドリア生物学
背景:
- 老化細胞は,老化に関連した分泌現象型 (SASP) を通して,年齢に関連する組織機能障害に寄与する.
- ミトコンドリアがSASPを調節しますが 正確なメカニズムは不明です
- ミトコンドリア外膜浸透 (MOMP) はアポトーシスの重要な出来事であり,老化とは異なる.
研究 の 目的:
- 細胞老化とSASPにおけるミトコンドリアの役割を調査する.
- ミトコンドリア動態とSASP誘導を結びつけるメカニズムを解明する.
- 老化におけるミトコンドリア経路を標的とした 治療戦略を探る
主な方法:
- 衰老細胞におけるミトコンドリア外膜浸透 (MOMP) の特徴.
- マイノリティのMOMP (miMOMP) でのBAXとBAKの役割の分析
- ミトコンドリアDNA (mtDNA) の放出とcGAS-STING経路の活性化の評価
- MOMP抑制が炎症と健康に与える影響を評価するために,老いたマウスの体内試験を行いました.
主要な成果:
- ミトコンドリアの外膜浸透性 (MOMP) は,ミトコンドリアのサブセット (マイノリティのMOMPまたはmiMOMP) の細胞衰老の特徴として識別される.
- miMOMPはBAXとBAKを必要とし,ミトコンドリアDNA (mtDNA) がサイトゾールに放出されます.
- サイトソリック mtDNAは,SASPの重要なレギュレータであるcGAS-STING経路を活性化します.
- MOMPのインビオ抑制は,炎症マーカーを減少させ,老いたマウスの健康状態を改善した.
結論:
- 細胞老化とアポトーシスは,ミトコンドリアに依存する同様の規制メカニズムを共有しています.
- 亜致死性ミトコンドリアアポプトシスストレス,特にmiMOMPはSASPの重要な要因です.
- miMOMP誘発の炎症を抑制することは,老化時の健康状態を改善するための潜在的な治療戦略です.
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