ACE2は,アミノ酸の栄養不良を微生物生態学と腸内炎症と関連付けています
Tatsuo Hashimoto1, Thomas Perlot, Ateequr Rehman
1IMBA, Institute of Molecular Biotechnology of the Austrian Academy of Sciences, 1030 Vienna, Austria.
Nature
|July 28, 2012
まとめ
アンジオテンシンI変換酵素2 (Ace2) 欠乏症は,アミノ酸のバランスと腸内微生物群を乱すことで,腸内炎症に対する感受性を高めます. これは,栄養不良が腸の問題をどのように引き起こしているかを説明します.
科学分野:
- 微生物学 微生物学とは
- 免疫学 免疫学とは
- 胃腸内科 胃腸内科
背景:
- 栄養失調は,世界中で10億人以上の人々に影響を及ぼし,しばしば下痢や腸の炎症を引き起こす.
- 食事の不均衡と腸の機能不全を結びつける正確なメカニズムは不明である.
- レニン-アンジオテンシン系 (RAS) 酵素であるアンジオテンシンI変換酵素2 (Ace2) は,様々な生理学的プロセスにおいて極めて重要です.
研究 の 目的:
- 腸内ホメオスタシスの維持におけるAce2の役割と,栄養不良による炎症との関連を調査する.
- Ace2が腸内免疫,微生物の構成,大腸炎の感受性に影響するメカニズムを解明する.
主な方法:
- 化学的に誘発された上皮損傷と大腸炎に対する感受性を評価するために,Ace2欠乏したマウスを研究した.
- 腸内アミノ酸ホメオスタシスの変化,抗菌性ペプチドの発現,腸内微生物群の構成を分析した.
- Ace2変異マウスの糞便の微生物群を,細菌のない野生型受容体に移植した.
- 食中のトリプトファンが,Ace2依存性腸の調節に与える影響を調査した.
主要な成果:
- Ace2欠乏症は,腸炎や大腸炎に対する感受性を著しく高めました.
- Ace2は,腸内のアミノ酸のバランス,抗微生物ペプチドの発現,およびRASから独立して腸内微生物の生態を調節する.
- Ace2変異のマウスの腸内微生物群の変化は,細菌のない宿主に対する大腸炎の感受性の増加を伝達した.
- 食中のトリプトファンは,腸内免疫と微生物群のAce2媒介調節に直接影響する.
結論:
- Ace2は,食事中のアミノ酸ホメオスタシス,先天性免疫,腸内微生物の組成の重要な調節剤です.
- Ace2の欠乏は,大腸炎への感染性感受性につながり,栄養不良に関連した腸炎症の分子基盤を提供します.
- Ace2媒介経路をターゲットにすることで,栄養不良に関連した胃腸疾患の治療戦略を提供することができます.
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