Improving skeletal muscle function without restoring dystrophin expression in cardiac tissue may exacerbate cardiomyopathy due to increased voluntary activity.
Dystrophin-deficient cardiomyopathy is becoming the dominant cause of death in patients with Duchenne muscular dystrophy (DMD), but its developmental process remains elusive.
Left ventricular thrombosis and systemic emboli have been demonstrated to complicate cardiomyopathy in Duchenne and Becker muscular dystrophy (DMD, BMD).
All dystrophin-associated proteins are decreased in abundance in the cardiomyopathic hamster heart, perhaps explaining why the cardiomyopathy is more severe than the myopathy.
Although this minigene fully normalized skeletal muscle force, it only partially corrected electrocardiogram and heart hemodynamics in dystrophin-null mdx mice that had moderate cardiomyopathy.
Young males presenting with apparent isolated cardiomyopathy or acute myocarditis may harbor dystrophin mutations without overt skeletal muscle pathology.
Thus current research efforts into the elucidation of the molecular mechanisms underlying these genetic diseases are not only directed towards studying skeletal muscle necrosis but also investigate abnormalities of heart and brain dystrophin-glycoprotein complexes in cardiomyopathy and brain deficiencies associated with muscular dystrophy.
Contrary to previous reports, which indicated the involvement of 5'-end mutations in cardiomyopathies as a result of dystrophin gene alterations, this study shows that despite the apparent concentration of deletions in two regions (5'-end and exons 47 through 49), no general conclusions can be drawn regarding the involvement of specific gene mutations in the development of cardiomyopathy.
These findings indicate that AAV-mediated cardiac transduction with microdystrophin might be a promising therapeutic strategy for the treatment of dystrophin-deficient cardiomyopathy.
Heart failure invariably affects patients with various forms of Muscular Dystrophy (MD), but the onset and molecular sequelae of altered structure and function resulting from full-length dystrophin (Dp427) deficiency in MD heart tissue are poorly understood.To better understand the role of dystrophin in cardiomyocyte development and the earliest phase of DMD cardiomyopathy, we studied human cardiomyocytes differentiated from induced pluripotent stem cells (hiPSC-CMs) obtained from the urine of a Deuchenne Muscular Dystrophy (DMD) patient.
Mutations of the dystrophin gene leading to a complete loss of the protein cause Duchenne muscular dystrophy (DMD), frequently associated with severe cardiomyopathy.
These results indicate that viral infection can influence the severity and penetrance of the cardiomyopathy that occurs in the hearts of dystrophin-deficient individuals.
Although mdx mice are deficient in dystrophin, they only develop mild indicators of cardiomyopathy before 1year-of-age, making therapeutic investigations using this model lengthy.