Mutations in the gene are a main cause of congenital heart disease. Several studies have addressed the phenotypic consequences of disrupting the gene locus, although animal models to date failed to recapitulate the full spectrum of the human disease. Here, we describe a new point mutation murine model, akin to its human counterpart disease-generating mutation. Our model fully reproduces the morphological and physiological clinical presentations of the disease and reveals an understudied aspect of-driven pathology, a primary right ventricular dysfunction. We further describe the molecular consequences of disrupting the transcriptional network regulated by in the heart and show that-dependent perturbation of the Wnt signaling pathway promotes heart dysfunction through alteration of cardiomyocyte metabolism. Our data provide mechanistic insights on how regulates heart function and metabolism, a link in the study of congenital heart disease, and confirms that our models are the first murine genetic models to our knowledge to present all spectra of clinically relevant adult congenital heart disease phenotypes generated by mutations in patients.

No abstract

Congenital heart disease (CHD) is the most frequent birth defect worldwide and the number of adult patients with CHD, now referred to as ACHD, is increasing. However the mechanisms whereby ACHD predisposes patients to heart dysfunction are still unclear. ACHD is strongly associated with metabolic syndrome, but how ACHD interacts with poor modern lifestyle choices and other comorbidities, such as hypertension, obesity and diabetes, is mostly unknown. Using a genetic mouse model of ACHD we showed that ACHD mice placed under metabolic stress (high fat diet) displayed decreased heart function. Comprehensive physiological, biochemical and molecular analysis showed that ACHD hearts exhibited early changes in energy metabolism that preceded cardiac dysfunction. Restoration of metabolic balance by metformin prevented the development of heart dysfunction in ACHD mice. This study reveals that early metabolic impairment reinforces heart dysfunction in ACHD predisposed individuals and diet or pharmacological interventions can be used to modulate heart function and attenuate heart failure and may be an important avenue for intervention in ACHD.