Cardioprotective effect of genetic ablation of the G-protein-coupled receptor kinase GRK2 in adult pancreatic β-cells during high-fat diet.

Cardiovascular diseases are a major comorbidity factor in patients with type 2 diabetes and a leading cause of death among them. Yet, mechanistically, how impairment in pancreatic islets alters cardiac function under different metabolic states remains largely unknown. Here, we investigate the role of the G-protein-coupled receptor kinase 2 (GRK2) in regulating islet adaptations to an obesogenic diet and its impact on myocardial function. Using a novel inducible β-cell-specific GRK2 knockout mouse model (βGRK2KO), we establish that loss of adult β-cell GRK2 delays metabolic islet maladaptation, protecting the heart against obesity-induced cardiac dysfunction. βGRK2KO are more insulin-sensitive than control mice and have improved cardiac function and myocardial morphology. Thus, genetic ablation of GRK2 in adult β-cells during an obesogenic diet play a cardioprotective role. This study prompts a novel therapeutic window for GRK2 intervention strategies for diabetic patients prone to cardiac dysfunction.