UC San Diego

Cardiolipin, the signature phospholipid of mitochondria, is crucial for mitochondrial function and architecture in the heart. Defects in cardiolipin remodeling processes and metabolism lead to cardiomyopathy, as seen in patients with Barth Syndrome (BTHS). Tafazzin is a major acyltransferase in CL remodeling that transfers linoleoyl groups to monolyso-CL until the final symmetric acyl composition is achieved. Mutations in Taz that result in BTHS cause inefficient transacylation between phosphoplipid-lysophospholipids, leading to cardiomyopathy. However, little is known as to the detailed molecular mechanisms by which Taz deficiency and consequent CL absnormalities lead to the progression of cardiomyopathy. In our present study, we found that loss of Tafazzin results in increased levels of cardiac stress markers, Anf and Bnp. Histological analysis demonstrated that mice with Taz deletions had thinner left ventricular walls and dilated left ventricular chambers relative to the control mice. Echocardiography analysis also showed that loss of Tafazzin causes decreased cardiac function. Together, these observations suggest that deletion of Tafazzin in cardiomyocytes results in dilated cardiomyopathy as seen in Barth Syndrome.