Type 2 diabetes

Neuroscience

Biology

Distension

Semaglutide

Endocrinology

Receptor

Agonist

Neuron

Endocrine system

Glucagon-like peptide-1

Glucagon-like peptide 1 receptor

Enteroendocrine cell

Internal medicine

Hormone

Gastric distension

Liraglutide

Medicine

Peripheral

Diabetes mellitus

Nature Metabolism

The anorexigenic peptide glucagon-like peptide-1 (GLP-1) is secreted from gut enteroendocrine cells and brain preproglucagon (PPG) neurons, which, respectively, define the peripheral and central GLP-1 systems. PPG neurons in the nucleus tractus solitarii (NTS) are widely assumed to link the peripheral and central GLP-1 systems in a unified gut–brain satiation circuit. However, direct evidence for this hypothesis is lacking, and the necessary circuitry remains to be demonstrated. Here we show that PPGNTS neurons encode satiation in mice, consistent with vagal signalling of gastrointestinal distension. However, PPGNTS neurons predominantly receive vagal input from oxytocin-receptor-expressing vagal neurons, rather than those expressing GLP-1 receptors. PPGNTS neurons are not necessary for eating suppression by GLP-1 receptor agonists, and concurrent PPGNTS neuron activation suppresses eating more potently than semaglutide alone. We conclude that central and peripheral GLP-1 systems suppress eating via independent gut–brain circuits, providing a rationale for pharmacological activation of PPGNTS neurons in combination with GLP-1 receptor agonists as an obesity treatment strategy. GLP-1 is an incretin hormone and neuromodulator produced by gut enterocytes and CNS neurons. Brierley et al. find that GLP-1 from peripheral and central sources acts independently through distinct gut–brain circuits to suppress eating.

Central and peripheral GLP-1 systems independently suppress eating