インテグリン結合キナーゼによる酸化低密度リポプロテイン誘発の血管内皮細胞死に対する保護
1Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA.
Circulation
|December 6, 2001
まとめ
インテグリン結合キナーゼ (ILK) は,血管内皮細胞を酸化LDL (oxLDL) 誘発のアポトーシスから保護する. ILKをアッププレギュレーションすることで,動脈硬化における内皮細胞損傷を予防することができます.
科学分野:
- 心血管生物学 心血管生物学
- 細胞シグナル伝達 細胞信号伝達
- 分子医学は分子医学である.
背景:
- インテグリン結合キナーゼ (ILK) は,細胞外マトリックスシグナル伝達に不可欠であり,好ましくは筋肉組織で発現します.
- ILKは,アポトーシスの重要な媒介体であるタンパク質キナーゼBのアップストリームレギュレータとして作用します.
- 酸化LDL (oxLDL) は,内皮細胞のアポトーシスによるアテロゲネシスに関与しています.
研究 の 目的:
- 血管内皮細胞における酸化LDL (oxLDL) 誘発のアポトーシスにおけるILKの役割を調査する.
- ILKがoxLDL誘発の細胞死に関与するシグナル伝達経路に影響を与えるかどうかを判断する.
主な方法:
- 逆転写ポリメラーゼ連鎖反応と西洋解析を用いてILK遺伝子転写と翻訳を調査した.
- 内皮細胞におけるILK遺伝子過剰発現のための再結合アデノウイルスベクトルを利用した.
- 2つの独立した測定方法を使用してアポトーシスを評価し,アポトーシスに関連する主要な要因 (bcl-2,bcl-xl,caspase 3,caspase 9) とp38 MAPK活性を分析しました.
主要な成果:
- 酸化LDL (oxLDL) 治療は,内皮細胞におけるILK遺伝子転写と翻訳の両方を増加させた.
- ILKの過剰発現は,ヒト動脈と猿のウイルス40型変異マウスリンパ性静脈内皮細胞の両方で,oxLDL誘発のアポトーシスと細胞死を著しく抑制しました.
- ILKは,p38ミトゲン活性化タンパク質キナーゼのoxLDL誘発活性化を抑制し,アポトーシスに関連するタンパク質の発現を調節した.
結論:
- インテグリン結合キナーゼ (ILK) は,血管内皮細胞における酸化LDL (oxLDL) 誘発のアポトーシスを予防する上で重要な規制的役割を果たします.
- ILKの活性を調節することは,動脈硬化における内皮細胞損傷を予防するための潜在的な治療戦略です.
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