フラクタルキン/CX3CR1システムはβ細胞機能とインスリン分泌を調節する
Yun Sok Lee1, Hidetaka Morinaga, Jane J Kim
1Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Diego, La Jolla, CA 92093, USA.
Cell
|April 16, 2013
まとめ
フラクタルキン (FKN) /CX3CR1システムは,臓の島ベータ細胞機能とインスリン分泌を調節する. FKN/CX3CR1シグナル伝達の障害は,2型糖尿病におけるβ細胞機能障害に寄与する.
科学分野:
- エンドクリノロジー エンドクリノロジー
- 免疫学 免疫学とは
- メタボリック疾患
背景:
- 臓の小島ベータ細胞機能不全は,2型糖尿病の中心にある.
- ベータ細胞機能におけるフラクタルキン (FKN) / CX3CR1シグナル伝達経路の役割は十分に理解されていません.
研究 の 目的:
- 臓島ベータ細胞機能とインスリン分泌の調節におけるFKN/CX3CR1システムの役割を調査する.
- 2型糖尿病の治療標的としてFKN/CX3CR1シグナル伝達の可能性を調査する.
主な方法:
- CX3CR1のノックアウト (KO) マウスとワイルドタイプ (WT) の littermates を利用しました.
- 評価されたグルコースとGLP1刺激によるインスリン分泌 in vivoおよびin vitro.
- 投与されたFKN in vivoおよびin vitroで,グルコース耐性およびインスリン分泌に対する効果を評価する.
- KOとWTマウスの孤立した小島と,FKN治療を受けたWT小島で遺伝子発現を分析した.
主要な成果:
- CX3CR1KOマウスは,グルコースとGLP1刺激によるインスリン分泌の低下を示した.
- In vivo FKN投与は,グルコース耐性を改善し,インスリン分泌を増加させた.
- 島根のFKN治療は,マウスとヒトの島根で細胞内Ca2+を強化し,インスリン分泌を強めた.
- KO島はベータ細胞機能の重要な遺伝子の発現を低下させ,FKN治療はWT島で発現を増加させた.
- 島FKN発現は,高齢化と高脂肪食/肥満とともに減少した.
結論:
- FKN/CX3CR1システムは,臓の小島ベータ細胞機能とインスリン分泌の重要な調節因子である.
- 老化と肥満で観察されるFKN/CX3CR1シグナリングの低下は,2型糖尿病におけるベータ細胞機能不全に寄与する可能性がある.
- FKN/CX3CR1経路を調節することで,2型糖尿病を治療する可能性がある.
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