GLP-3 is a synthetic peptide designed as a triple agonist targeting glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon receptors for advanced laboratory research. It is utilized in in vitro and animal model studies to explore complex metabolic regulation, including glucose homeostasis, lipid metabolism, and energy balance pathways. Researchers employ retatrutide to examine its binding affinity and signaling properties across multiple receptor types in cell lines and rodent models under controlled conditions.