Signalling in the gut endocrine axis

•Gut hormones like GLP-1 coordinate digestion, metabolism and appetite.•GLP-1 based therapies are effective treatments for type 2 diabetes and obesity.•Nutrient sensing in gut endocrine cells is directly linked to nutrient absorption.•Bacterial metabolites directly modulate gut hormone release.•Bariatric surgery enhances GLP-1 and insulin secretion and improves glucose tolerance.

Enteroendocrine cells are sensory cells located in the intestinal epithelium that produce a variety of hormonal regulators of gastrointestinal physiology, metabolism and food intake. They detect the absorption of a wide range of ingested nutrients via pathways that include transporter-mediated uptake, G-protein coupled receptors and ion channels. This review will describe mechanisms by which the L-cells that produce Glucagon Like Peptide-1 (GLP-1) respond to different components of ingested food, and the importance of these pathways not only for understanding physiology, but also for developing new treatments for type 2 diabetes and obesity.