Dissociable hindbrain GLP1R circuits for satiety and aversion.

Area of Science:

• Neuroscience
• Endocrinology
• Pharmacology

Background:

• Glucagon-like peptide-1 receptor (GLP1R) agonists are effective obesity treatments but cause nausea and vomiting.
• These aversive responses may contribute to the drugs' efficacy in reducing food intake.

Purpose of the Study:

• To investigate the brain circuits linking satiety and aversion.
• To determine if these circuits are functionally separable and can be selectively targeted for weight loss therapies.

Main Methods:

• In vivo two-photon imaging of hindbrain GLP1R neurons in response to nutritive and aversive stimuli.
• Selective manipulation of GLP1R-expressing neurons in the area postrema (AP) and nucleus of the solitary tract (NTS).
• Anatomical tracing and behavioral analyses to map neural pathways and assess feeding behavior.

Main Results:

• Hindbrain GLP1R neurons are crucial for the efficacy of GLP1R-based obesity drugs.
• NTS^GLP1R neurons are primarily tuned to nutritive stimuli and drive satiety without aversion.
• AP^GLP1R neurons are broadly responsive and trigger aversion, leading to reduced food intake.

Conclusions:

• Neural circuits for satiety and aversion mediated by GLP1R are functionally separable.
• Targeting NTS^GLP1R neurons offers a potential strategy for weight loss therapies with reduced adverse effects.
• Selective activation of NTS^GLP1R neurons can promote satiety and reduce food intake without inducing nausea or vomiting.