滑らかな筋肉細胞は,フローと損傷に対する内皮細胞の反応をオーケストラ化します
Mercedes Balcells1, Jordi Martorell, Carla Olivé
1Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA. merche@mit.edu
Circulation
|May 12, 2010
まとめ
血管の滑らかな筋肉細胞 (SMC) は,血流によって活性化される,内皮細胞 (EC) mTORシグナリングを調節する. このクロスストークは,介入後のEC回復に影響を与え,新しいステント設計を提案します.
科学分野:
- 血管生物学 血管生物学とは
- 内皮細胞と滑らかな筋肉細胞のシグナル伝達
- 心血管研究に関する研究.
背景:
- ラパミシン (mTOR) 信号調節の血管性哺乳類標的は,介入後の滑らかな筋肉細胞 (SMC) 増殖に影響しますが,内皮細胞 (EC) 毒性を引き起こす可能性があります.
- 血管のアーキテクチャは,ECとSMCをパラクリン通信のために配置し,SMCは直接の流れから保護されています.
- ECとSMCにおけるmTORシグナル伝達に対するフローの異なる影響と,EC mTORにおけるSMCの規制的役割を仮説化した.
研究 の 目的:
- 血管ECとSMCにおけるmTORシグナル伝達に対する血流の差異的影響を調査する.
- ECにおけるフロー誘発型mTORシグナリングに関するSMCの規制役割を決定する.
- 血管介入とステント設計におけるEC-SMCクロストークの影響を明らかにする.
主な方法:
- SMCsおよび/またはECsの冠動脈の流れへの浸透バイオリアクターの曝露.
- フォスフォ-S6リボソームタンパク質 (p-S6RP) の発現を評価するために,フローサイトメトリ,免疫光,および免疫ブロッティングを行います.
- ステント付き豚動脈とシロリムスステントエリューションを用いたin vivo検証.
主要な成果:
- 流れがEC p-S6RP (mTORターゲット) 発現を著しく増加させた.
- SMC S6RPは成長因子に反応したが,フローに反応しなかった.
- SMCsは,フロー誘発EC mTORシグナリングを阻害し,テンシロリムスはこれらの効果を廃止した.
- ステントが置かれた動脈では,EC p-S6RPはSMCから最も遠くにあり,シロリムスのエリューションでは存在しない.
結論:
- 光の流れは,ECのmTOR経路を活性化する.
- SMCは,フロー誘発の内皮のmTORシグナル伝達に抑制効果を発揮する.
- 新しいフロー刺激とEC-SMCクロストークメカニズムを特定しました.
- 発見は,流動と薬物効果を考慮して,局所抗増殖剤の投与と将来のステント設計のための戦略を伝える.
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