上腸の脂質は,腸-脳-肝臓軸を誘発し,グルコースの生産を調節する
Penny Y T Wang1, Liora Caspi, Carol K L Lam
1Toronto General Hospital Research Institute, University Health Network, Toronto M5G 1L7, Canada.
Nature
|April 11, 2008
まとめ
上腸の脂質は,腸,脳,肝臓を含む神経経路を活性化し,グルコースの産生を抑制する. この新たに発見された腸-脳-肝臓軸は,グルコースホメオスタシスの調節に極めて重要です.
科学分野:
- メタボリック生理学 メタボリック生理学
- 神経内分泌学の神経内分泌学
- 胃腸の生理学 胃腸の生理学
背景:
- エネルギーとグルコースホメオスタシスは,食物の摂取と肝臓のグルコース生成に依存する.
- 上腸は栄養素の吸収に重要な役割を果たし,腸-脳軸経由で食物の摂取に影響を与えます.
- 脳と肝臓の軸は,血中脂質レベルに基づいてグルコースの生産を調節することを提案されています.
研究 の 目的:
- 上部腸内脂質が,グルコースホメオスタシスを調節するために腸-脳-肝臓神経軸を活性化するという仮説を検証する.
- 腸の上部における脂質感知に関与する神経経路と,その影響がグルコース生産に及ぼす影響を明らかにする.
主な方法:
- ネズミの上腸に脂質を直接投与する.
- アシル-コア合成と神経経路の薬理学的阻害 (テトラカイン,MK-801).
- サブディアフラグマティック・ヴァゴトミー,腸のヴァガル・デアフェレンテーション,肝臓のヴァゴトミーを含む外科的介入.
主要な成果:
- 上腸の脂質は,長鎖脂肪酸アシル-CoA (LCFA-CoA) のレベルを上昇させ,肝臓のグルコース産生を抑制しました.
- LCFA-CoA合成の阻害または神経封鎖は,脂質誘発によるグルコース産生抑制を廃止しました.
- ヴァゴトミーとMK-801の中央投与は,腸-脳-肝臓のシグナル伝達を妨害し,グルコース生産の抑制を防止しました.
結論:
- 上腸の脂質は,腸,脳,肝臓をつなぐ神経軸を活性化し,グルコースの産生を抑制する.
- この経路は,LCFA-CoAによって媒介され,神経のシグナル伝達を含み,グルコースホメオスタシスの調節のための新しいメカニズムを表しています.
- この発見は,肝臓のグルコース排出を制御するために脂質を感知する上部腸の以前に評価されていない役割を明らかにしています.
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