Mitochondria in Duchenne Muscular Dystrophy-induced Cardiomyopathy: A Prospective Therapeutic Target to Improve Treatment Response

Abstract

Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disease caused by mutations to the dystrophin gene - resulting in deficiency of dystrophin protein, loss of myofiber integrity in skeletal and cardiac muscle, and eventual cell death and replacement with fibrotic tissue. Pathologic cardiac manifestations occur in nearly every DMD patient, with development of cardiomyopathy - the leading cause of death - inevitable by adulthood. As early cardiac abnormalities are difficult to detect, timely diagnosis and appropriate treatment modalities remain a challenge. There is no cure for DMD – treatment is aimed at delaying disorder progression and alleviating symptoms. A comprehensive understanding of the pathophysiological mechanisms is crucial to development of targeted treatments. While established hypotheses of underlying mechanisms include sarcolemmal weakening, upregulation of pro-inflammatory cytokines, and perturbed ion homeostasis, mitochondrial stress has recently come into focus as a potential key contributor. Several experimental compounds targeting the skeletal muscle pathology of DMD are in development, but effects of such agents on cardiac function remain unclear. Synergistic integration of small molecule- and gene-target-based drugs with metabolic, immune, or ion balance-enhancing compounds into a combinatorial therapy offers potential for treating dystrophin deficiency-induced cardiomyopathy, making it crucial to understand the underlying mechanisms driving the disorder.