カスパース活性化が先行し,タングルにつながります
Alix de Calignon1, Leora M Fox, Rose Pitstick
1MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Alzheimer's Disease Research Laboratory, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.
Nature
|April 2, 2010
まとめ
ニューロフィブリラータングル (NFT) ではなく,カスパースの活性化が,アルツハイマー病のモデルにおけるタウ病理を誘発する. この発見は,タングルではなく,溶解性タウの種が神経変性を誘発し,新しい治療標的を提供することを示唆しています.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- 病理学 パトロジー
背景:
- 死後の研究では,神経線維細胞の絡み (NFTs) が,アルツハイマー病 (AD) と前頭前野性認知症におけるニューロン死亡と関連している.
- NFTはカスパース活性化とアポトーシスに関連しており,タングルは神経変性を引き起こすことを示唆しています.
研究 の 目的:
- カスパース活性化とNFT形成の間の時間的関係を in vivoで調査する.
- タウ病変と神経変性発現におけるカスパース分裂タウの役割を明らかにする.
主な方法:
- 生きているタウ変異遺伝子マウス (Tg4510株) のインビヴォマルチフォトンイメージング.
- カスパース活性化とNFT形成の観察.
- 野生型の4重複型タウ (tau-4R) とカスパース分裂型タウ構造を野生型のマウスに導入した.
主要な成果:
- カスパースのアクティベーションは,NFTの形成に数時間から数日間先行する.
- 新しいNFTは1日以内に形成され,ニューロンは抑制されたカスパース活性で生き残ります.
- カスパースの活性化,タウの断片化,および結合は,タウ-4Rの導入によって誘発された.
- カスパゼで割れたタウミメティック誘発集積体,タングルエピトープ,内生的なタウ募集.
結論:
- 新しいモデルでは,カスパースの活性化がタウ分裂を誘発し,NFTの形成につながることを提案しています.
- NFTは,急性ニューロン死亡への"経路外"であり,タングルベアリングニューロンは長生きしている可能性があります.
- 繊維性タウではなく,溶解性タウ種が,神経変性における主要な毒性物質である可能性が高い.
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