拡張性心筋症候群の患者におけるチチンの発現変化,心筋硬化,左心室機能の変化
Sherif F Nagueh1, Gopi Shah, Yiming Wu
1Section of Cardiology, Department of Medicine, Baylor College of Medicine, 6550 Fannin, SM-1256, Houston, TX 77030-2717, USA. sherifn@bcm.tmc.edu
Circulation
|July 9, 2004
まとめ
心不全では,巨大なタンパク質のチチンは,より適合性の高いN2BA同型にシフトし,心筋硬直を軽減し,静脈充填と運動耐性に影響を及ぼします. これは,変化したチチンの発現が拡張性心筋病の鍵であることを示唆しています.
科学分野:
- 心血管生物学 心血管生物学
- 筋肉生理学 筋肉生理学
- バイオケミストリー バイオケミストリー
背景:
- 心不全における巨大タンパク質チチンの役割は十分に理解されていません.
- 非発血性伸縮性心筋病変による終末期心不全におけるチチンの発現を調査した.
- ティチン発現,左心室 (LV) の心筋硬化,およびLV機能の間の関係を調べました.
研究 の 目的:
- 心不全の患者におけるチチンのイソフォーム発現を調査する.
- 動脈硬化とLV機能に対するチチンの発現の影響を決定する.
- ティチン発現と心不全の臨床パラメータの相関性を調査する.
主な方法:
- SDS-アガロースゲルを使用してチチンの同型 (N2BとN2BA) を分析した.
- LV筋のストライプで測定された受動筋の硬さ.
- 侵襲性血液動力学とドップラー心声撮影を使用して,LV機能を評価しました.
- 定量化されたチチン結合タンパク質.
主要な成果:
- 心不全患者のN2BA:N2Bチチンの同型比の増加対照群.
- 高度なN2BA:N2B比率を有する患者における受動的な筋肉の硬さの低下.
- N2BA:N2B比とダイアストリック充填パラメータ,ダイアストリック終端の体積/圧力比,運動耐性 (ピークのO2消費量) の間の相関が見つかりました.
- 増幅されたN2BA発現は,チチン結合タンパク質の増加と相関する.
結論:
- トータルチチンの含有量は,衰弱した心臓では変わらない.
- 心不全におけるコンプライアントのN2BAチチン・アイソフォームの割合の増加は,心筋硬直を著しく低下させる.
- 変異したチチンの発現はダイアストリック充填に影響を与え,チチンを結合するタンパク質による細胞信号伝達経路を伴う可能性があります.
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