自然に発生する不飽和型リソホスファティド酸によって誘発された血管の再構築 in vivo
Kenji Yoshida1, Wataru Nishida, Ken'ichiro Hayashi
1Department of Neuroscience, Osaka University Graduate School of Medicine (D13), 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Circulation
|September 25, 2003
まとめ
不飽和リソホスファティド酸 (LPA) は,ヒトの動脈硬化症を模倣して,血管の再構築とネオインティマ形成をインビオで誘導します. この研究は,LPAを強調しています.
科学分野:
- 心血管生物学 心血管生物学
- 分子医学は分子医学である.
- 細胞生物学 細胞生物学
背景:
- リソホスファティド酸 (LPA) は,様々な細胞プロセスに関与するシグナル伝達脂質である.
- 不飽和のLPAは,飽和のLPAではないが,以前は,血管滑らかな筋肉細胞 (VSMC) の無差別化を誘発することが判明した.
- この非差別化には,ERKとp38MAPKの活性化があり,VSMCの増殖と移住につながります.
研究 の 目的:
- 不飽和 (18:1 LPA) と飽和 (18:0 LPA) リソフォスファティド酸が血管系に及ぼすインビボ効果を調査する.
- 不飽和のLPAが,生体の中で血管の再編成とネオインティマ形成を誘発するかどうかを判断する.
主な方法:
- ネズミの常軌動脈 (CCA) は18:1 LPAまたは18:0 LPAで治療されました.
- 治療されたCCAの組織学および生化学分析が行われました.
- トレーサー研究 ([3H]18:1 LPA) は,血管壁におけるLPAの組み込みと代謝を評価するために使用されました.
主要な成果:
- 18:1 LPAではなく18:0 LPAで,血管の再編成が顕著に誘発され,主にネオインティマ形成である.
- 血管壁には,VSMCの脱差を誘発する十分な量の代謝されていない18: 1のLPAが検出されました.
- 18:1 LPA誘発のネオインティマ形成は,ERKとp38MAPKの活性化に依存していた.
- 組織学的に 18:1 LPAで治療されたCCAは,人間の動脈硬化動脈に似ていた.
結論:
- この研究は,自然に発生する不飽和のLPAが,体内において血管の再構築を誘発する役割について最初の証拠を提供します.
- この発見は,ネオインティマ形成を研究するための新しい動物モデルを確立しています.
- 不飽和のLPAは,ネオインティマ形成によって特徴づけられる血管疾患の潜在的な治療標的を代表しています.
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