Mechanistic study demonstrating that ectopic hepatic GLP-1R agonism (targeting hepatocyte-expressed GLP-1R rather than CNS or islet receptors) enhances weight loss efficacy of GLP-1 analogues without the adverse cardiovascular effects associated with hepatic glucagon receptor agonism. Proposes liver-targeted GLP-1R engagement as a strategy to achieve triagonist-level weight loss while avoiding glucagon-mediated cardiac side effects. Identifies ectopic hepatic GLP-1R signaling as a novel target for next-generation obesity pharmacotherapy—providing mechanistic basis for improved semaglutide analogs that preserve liver benefits while avoiding cardiovascular liabilities.
Abstract
OBJECTIVES: Unimolecular triagonists drive substantial weight loss in patients with obesity by engaging the glucagon-like peptide 1 receptor (GLP-1R) and glucose dependent insulinotropic polypeptide receptor (GIPR) to reduce food intake (FI) and the hepatic glucagon receptor (GcgR) to enhance energy expenditure (EE). However, their development has been challenged by deleterious cardiovascular (CV) effects, including increased heart rate (HR), elongated QTc, and arrhythmia mediated by GcgR agonism. GLP-1R mono-agonists on the other hand improve both obesity and CV outcomes with negligible effects on EE. We sought to imbue peptide GLP-1R agonists with an EE enhancing effect by combining them with ectopic GLP-1R expression and agonism in hepatocytes.
METHODS: We used an adeno-associated virus (AAV) to induce the expression of a functional, liver-specific GLP-1R combined with traditional peptide agonist treatment to drive greater body weight loss via reduced energy intake and increased energy expenditure.
RESULTS: Agonism of the ectopic GLP-1R with either semaglutide, a cAMP biased GLP-1R analogue (NNC5840), or a dual GLP-1R/GIPR agonist in wild-type (WT) diet induced obese (DIO) mice led to enhanced EE and improved weight loss compared to peptide agonist treatment alone.
CONCLUSIONS: This represents a novel mechanism for achieving poly-pharmacology to treat obesity.
Authors
Douros, Jonathan D; Capozzi, Megan; Novikoff, Aaron; Mokrosinski, Jacek; DuBois, Barent; Stock, Joseph; Rohlfs, Rebecca; Anderson, Mikayla; Jedrzejcyk, Dominika J; Poulsen, Svend; Blenke, Erik Oude; Dago, Tomas; Huus, Kasper; Nørby, Peder L; Kobberup, Sune; Rivir, Marita; Sorrell, Joyce; Mowery, Stephanie A; Drucker, Daniel J; D'Alessio, David A; Campbell, Jonathan E; Müller, Timo D; Perez-Tilve, Diego; Finan, Brian; Knerr, Patrick J
Keywords
Energy expenditureGLP-1GlucagonObesityPharmacology