| Autor: |
Snider PL; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Sierra Potchanant EA; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Sun Z; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Edwards DM; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Chan KK; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Matias C; Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA., Awata J; Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA., Sheth A; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Pride PM; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Payne RM; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Rubart M; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Brault JJ; Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA., Chin MT; Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA., Nalepa G; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA., Conway SJ; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46033, USA. |
| Abstrakt: |
Cardiomyopathy is the predominant defect in Barth syndrome (BTHS) and is caused by a mutation of the X-linked Tafazzin (TAZ) gene, which encodes an enzyme responsible for remodeling mitochondrial cardiolipin. Despite the known importance of mitochondrial dysfunction in BTHS, how specific TAZ mutations cause diverse BTHS heart phenotypes remains poorly understood. We generated a patient-tailored CRISPR/Cas9 knock-in mouse allele ( Taz PM ) that phenocopies BTHS clinical traits. As Taz PM males express a stable mutant protein, we assessed cardiac metabolic dysfunction and mitochondrial changes and identified temporally altered cardioprotective signaling effectors. Specifically, juvenile Taz PM males exhibit mild left ventricular dilation in systole but have unaltered fatty acid/amino acid metabolism and normal adenosine triphosphate (ATP). This occurs in concert with a hyperactive p53 pathway, elevation of cardioprotective antioxidant pathways, and induced autophagy-mediated early senescence in juvenile Taz PM hearts. However, adult Taz PM males exhibit chronic heart failure with reduced growth and ejection fraction, cardiac fibrosis, reduced ATP, and suppressed fatty acid/amino acid metabolism. This biphasic changeover from a mild-to-severe heart phenotype coincides with p53 suppression, downregulation of cardioprotective antioxidant pathways, and the onset of terminal senescence in adult Taz PM hearts. Herein, we report a BTHS genotype/phenotype correlation and reveal that absent Taz acyltransferase function is sufficient to drive progressive cardiomyopathy. |
