What is the Origin of TGR5 Receptor?

The term "TGR5" is an acronym for "Takeda G protein-coupled receptor 5," initially characterized as an orphan receptor by the pharmaceutical company Takeda, before its ligand was identified as bile acids. This discovery established a novel signaling pathway that directly links the gut's bile acid metabolism to systemic endocrine and metabolic regulation. It has become a significant focal point in gastroenterology and metabolic endocrinology research.

What is the Mechanism of TGR5 Receptor?

Upon binding of bile acids, the TGR5 receptor initiates a G-protein signaling cascade that typically leads to the rapid generation of the second messenger cyclic AMP (cAMP). In the intestinal L cells, TGR5 activation stimulates the release of the incretin hormone Glucagon-like Peptide-1 (GLP-1), which in turn enhances glucose-dependent insulin secretion. In brown adipose tissue, this activation promotes non-shivering thermogenesis and increases overall energy expenditure by upregulating uncoupling proteins.

TGR5 Receptor

Meaning

The TGR5 Receptor is a G protein-coupled receptor, formally known as the G-protein-coupled bile acid receptor 1 (GPBAR1), which is potently activated by circulating bile acids. This receptor is strategically expressed in various metabolic tissues, including the gallbladder, intestine, liver, and brown adipose tissue, serving as a critical sensor for the bile acid pool. TGR5 activation mediates the non-genomic effects of bile acids, influencing systemic energy expenditure, glucose metabolism, and the secretion of essential gut hormones.