Hypothalamic bile acid-TGR5 signaling protects from obesity

Cell Metab. 2021 Jul 6;33(7):1483-1492.e10. doi: 10.1016/j.cmet.2021.04.009. Epub 2021 Apr 21.

Abstract

Bile acids (BAs) improve metabolism and exert anti-obesity effects through the activation of the Takeda G protein-coupled receptor 5 (TGR5) in peripheral tissues. TGR5 is also found in the brain hypothalamus, but whether hypothalamic BA signaling is implicated in body weight control and obesity pathophysiology remains unknown. Here we show that hypothalamic BA content is reduced in diet-induced obese mice. Central administration of BAs or a specific TGR5 agonist in these animals decreases body weight and fat mass by activating the sympathetic nervous system, thereby promoting negative energy balance. Conversely, genetic downregulation of hypothalamic TGR5 expression in the mediobasal hypothalamus favors the development of obesity and worsens established obesity by blunting sympathetic activity. Lastly, hypothalamic TGR5 signaling is required for the anti-obesity action of dietary BA supplementation. Together, these findings identify hypothalamic TGR5 signaling as a key mediator of a top-down neural mechanism that counteracts diet-induced obesity.

Keywords: GPBAR1; TGR5; bile acids; body weight; diet; energy expenditure; food intake; hypothalamus; obesity; sympathetic nervous system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bile Acids and Salts / metabolism*
  • Body Weight / genetics
  • Energy Metabolism / genetics
  • HEK293 Cells
  • Humans
  • Hypothalamus / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Obese
  • Mice, Transgenic
  • Obesity / genetics
  • Obesity / metabolism*
  • Obesity / prevention & control
  • Receptors, G-Protein-Coupled / genetics
  • Receptors, G-Protein-Coupled / metabolism*
  • Signal Transduction / physiology

Substances

  • Bile Acids and Salts
  • Gpbar1 protein, mouse
  • Receptors, G-Protein-Coupled