血小板ポリフォスファートは,生体内では,炎症を誘発するおよび凝固を促す媒介体である
Felicitas Müller1, Nicola J Mutch, Wolfdieter A Schenk
1Department of Molecular Medicine and Surgery and Center for Molecular Medicine, Karolinska Institutet, Stockholm S-171 76, Sweden.
Cell
|December 17, 2009
まとめ
活性化された血小板は,炎症と血液の凝固を誘発する分子である無機ポリフォスファート (polyP) を放出します. フォスファタゼでポリPを標的とした治療は,マウスの血小板駆動性血栓形成と炎症を減少させた.
科学分野:
- バイオケミストリー バイオケミストリー
- 血液学 ヘマトロジ
- 免疫学 免疫学とは
背景:
- 血小板は,血液静止,血栓形成,炎症において極めて重要です.
- 血小板とこれらのプロセスを結びつける分子機構は,現在調査中です.
研究 の 目的:
- 活性化された血小板によって放出される無機ポリフォスファート (polyP) の役割を調査する.
- 血栓形成,炎症,凝固におけるポリPの関与を決定する.
主な方法:
- ポリPがXII因子と結合し,その活性化を研究した.
- ブラジキニンの放出とマウスの血管透過性に対するポリPの効果を評価した.
- フェクターXII,ブラジキニン受容体,およびフォスファタゼがポリP媒介作用に及ぼす影響を研究した.
- プラズマの凝固と肺栓塞のモデルにおけるpolyPの役割を調べた.
- Hermansky-Pudlak症候群患者の血におけるpolyPの効果を分析した.
主要な成果:
- 活性化された血小板はPolyPを放出し,PolyPはXII因子を活性化し,ブラジキニンの放出を誘発する.
- PolyPは,血管の透過性と液体の流出を増加させ,因子XIIとブラジキニン受容体に依存する効果をもたらします.
- PolyPは,接触経路経由でプラズマの凝固を開始し,致死性肺栓塞を引き起こす.
- フォスファタゼでポリPを標的にすると,血小板の血栓活性および血栓形成が抑制されます.
- PolyP添加は,ヘルマンスキ・プードラック症候群患者の血における不完全な凝固を修正する.
結論:
- 無機ポリフォスファート (polyP) は,活性化された血小板によって放出される新しい媒介物質です.
- PolyPは,血小板に起因する炎症性および血の凝固を促す疾患の根本的な役割を果たしています.
- ポリPをターゲットにすることは,血栓性および炎症性疾患に対する潜在的な治療戦略です.
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