GRK-biased adrenergic agonists for the treatment of type 2 diabetes and obesity

Abstract

Biased agonism of G protein-coupled receptors (GPCRs) offers potential for safer medications. Current efforts have explored the balance between G proteins and β-arrestin; however, other transducers like GPCR kinases (GRKs) remain understudied. GRK2 is essential for β₂ adrenergic receptor (β₂AR)-mediated glucose uptake, but β₂AR agonists are considered poor clinical candidates for glycemic management due to G_s/cyclic AMP (cAMP)-induced cardiac side effects and β-arrestin-dependent desensitization. Using ligand-based virtual screening and chemical evolution, we developed pathway-selective agonists of β₂AR that prefer GRK coupling. These compounds perform well in preclinical models of hyperglycemia and obesity and demonstrate a lower potential for cardiac and muscular side effects compared with standard β₂-receptor agonists and incretin mimetics, respectively. Furthermore, the lead candidate showed favorable pharmacokinetics and was well tolerated in a placebo-controlled clinical trial. GRK-biased β₂AR partial agonists are thus promising oral alternatives to injectable incretin mimetics used in the treatment of type 2 diabetes and obesity.

Keywords: BRET; GLP-1; GPCR; GRK; beta-2 agonists; biased agonism; diabetes; metabolism; obesity; skeletal muscle.