GLP-1 increases preingestive satiation via hypothalamic circuits in mice and humans

Area of Science:

• Neuroscience
• Endocrinology
• Metabolic Diseases

Background:

• Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are established antiobesity medications.
• The exact central nervous system mechanisms underlying GLP-1RA efficacy are not fully understood.

Purpose of the Study:

• To elucidate the neural pathways through which GLP-1RAs induce preingestive satiation.
• To identify specific neuronal populations involved in GLP-1RA-mediated appetite regulation.

Main Methods:

• Administration of GLP-1RAs to individuals with obesity and analysis of their subjective satiety.
• Brain tissue analysis in humans and mice to locate GLP-1 receptor (GLP-1R) expressing neurons.
• Optogenetic manipulation and calcium imaging of dorsomedial hypothalamus (DMH) GLP-1R neurons in mice.
• Investigating the interaction between DMH^GLP-1R neurons and arcuate nucleus NPY/AgRP neurons.

Main Results:

• GLP-1RA administration increased preingestive satiation in patients with obesity.
• GLP-1R neurons were identified in the DMH, a key hypothalamic area.
• Activation of DMH^GLP-1R neurons mimicked satiation effects.
• These neurons showed increased activity during eating behavior following GLP-1RA treatment.
• A functional connection between DMH^GLP-1R and ARC^NPY/AgRP neurons regulating food intake was established.

Conclusions:

• GLP-1RAs exert their antiobesity effects by modulating preingestive satiation through a hypothalamic mechanism.
• DMH^GLP-1R neurons are critical for encoding preingestive satiation and mediating GLP-1RA action.
• The interplay between DMH^GLP-1R and ARC^NPY/AgRP neurons represents a novel target for obesity interventions.