在人类胆汁中发现的微生物结合胆汁盐激活胆汁盐受体TGR5和FXR
Ümran Ay1, Martin Leníček2, Raphael S Haider3,4,5
1Department of General, Visceral and Transplant Surgery, University Hospital Aachen, Aachen, Germany.
Hepatology communications
|March 22, 2024
概括
新发现的微生物胆汁盐结合物 (MBSC) 激活宿主受体TGR5和FXR. 然而,MBSCs在人体循环中没有显著发现,这表明对肠肝信号传递的影响很小.
科学领域:
- 肠 - 肝轴研究研究
- 微生物的新陈代谢和宿主信号传递.
- 胆盐生物学 胆盐生物学
背景情况:
- 胆盐调解肠肝轴的通信. 胆盐调解肠肝轴的通信.
- 微生物胆汁盐合物 (MBSCs) 是一个新发现的类.
- 研究MBSC激活宿主受体TGR5和FXR及其循环.
研究的目的:
- 为了确定MBSC是否激活塔克达G蛋白结合受体5 (TGR5) 和法尔内索伊德X受体 (FXR).
- 评估MBSC进入人体全身和肠肝循环的情况.
- 了解MBSCs在肠肝轴上的生理相关性.
主要方法:
- 用氨基酸合成 (氧) 胆酸的N-胺基酸.
- 使用无细胞和基于细胞的测定来评估受体激活.
- 在患者中腹腔血液,门血液和胆汁中量化MBSCs.
主要成果:
- MBSC激活了TGR5和FXR,而FXR的激活取决于胆盐进口商.
- 在MBSC中,对TGR5和FXR的亲和力与宿主胆盐结合物的亲和力相当.
- 个别的MBSC在人类中肠和门血液 (<2.5nmol/L) 中基本上无法检测到.
- 在胆汁中发现了MBSC的Leu和Phe变体 (高达213ppm).
结论:
- MBSCs激活宿主受体TGR5和FXR,并通过关键的肠道和肝脏输送器进行运输.
- 在人类中,MBSCs的系统循环是最小的.
- 低系统水平表明MBSC对人类肠肝TGR5/FXR信号传递的影响有限.
- 胆道MBSCs的起源和功能需要进一步调查.
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