Institute of Pharmacy, Department of Pharmacology, University of Tübingen, Tübingen, Germany.
Islets. 2012 Sep-Oct;4(5):333-8. doi: 10.4161/isl.22383. Epub 2012 Sep 1.
Bile acids (BAs) are important signaling molecules that are involved in the regulation of their own metabolism, lipid metabolism, energy expenditure and glucose homeostasis. The nuclear farnesoid X receptor (FXR) and the G-protein-coupled TGR-5 are the most prominent BA receptors. FXR is highly expressed in liver and activation of liver FXR profoundly affects glucose homeostasis. Strikingly, the effect of FXR activation on glucose metabolism seems to depend on the nutritional status of the organism, i.e., slimness or obesity. Recently, it became evident that FXR is present in pancreatic β cells and that activation of β cell FXR contributes to the regulation of glucose homeostasis. Interestingly, FXR activation increases glucose-induced insulin secretion by non-genomic effects on stimulus-secretion coupling. The first chapter of this review shortly introduces the role of liver FXR in glucose metabolism, the second part focuses on the impact of FXR in lean and obese animals, and the third chapter highlights the significance of FXR in β cells.
胆汁酸（BAs）是重要的信号分子，参与自身代谢、脂质代谢、能量消耗和葡萄糖稳态的调节。核法尼醇 X 受体（FXR）和 G 蛋白偶联型受体 5（TGR-5）是最主要的 BA 受体。FXR 在肝脏中高表达，激活肝脏 FXR 可显著影响葡萄糖稳态。引人注目的是，FXR 激活对葡萄糖代谢的影响似乎取决于机体的营养状态，即肥胖或消瘦。最近，人们发现 FXR 存在于胰岛β细胞中，激活β细胞 FXR 有助于调节葡萄糖稳态。有趣的是，FXR 激活通过对刺激-分泌偶联的非基因组作用增加葡萄糖诱导的胰岛素分泌。本篇综述的第一章简要介绍了肝脏 FXR 在葡萄糖代谢中的作用，第二章重点介绍了 FXR 在瘦素和肥胖动物中的作用，第三章强调了 FXR 在β细胞中的意义。
