Research

Hormonal

Dual GLP-1/GIP receptor agonism (e.g., tirzepatide) produces synergistic body weight loss compared to selective GLP-1 receptor agonists, a mechanism dependent on the interaction of signals in neurotensin-expressing neurons (Nts CeA) within the central amygdala.

Dual GLP-1/GIP medications (like tirzepatide) are more effective for weight loss than GLP-1-only drugs because they activate a specific brain pathway (neurotensin neurons in the central amygdala) that GLP-1 drugs alone do not fully engage. This biological synergy is the reason for their superior efficacy, not just better stomach tolerance.

GoodSupportsHIGH confidence
Disabling Nts CeA neurons selectively reduces the synergistic effect of dual GLP1R/GIPR agonist administration on body weight.
Claire H. Feetham et al. · Molecular Metabolism · 2025

Why this rating

High-quality preclinical evidence using genetic manipulation (knockout/silencing) in mice, though not human clinical data.

Source

Downstream interaction by glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide agonism is required for synergistic effects on body weight

Claire H. Feetham et al. · Molecular Metabolism · 2025

DOI 10.1016/j.molmet.2025.102214

mechanism_onlyCited 3×
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DOI resolved against Crossref · corpus check 2026-06-10

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