Targeting matrix metalloproteinase activity and expression for the treatment of viral myocarditis.

Infectious agents including viruses can infect the heart muscle, resulting in the development of heart inflammation called myocarditis. Chronic myocarditis can lead to dilated cardiomyopathy (DCM). DCM develops from the extensive extracellular matrix (ECM) remodeling caused by myocarditis and may result in heart failure. Epidemiological data for viral myocarditis has long suggested a worse pathology in males, with more recent data demonstrating sex-dependent pathogenesis in DCM as well. Matrix metalloproteinases (MMPs), long known modulators of the extracellular matrix, have important roles in mediating heart inflammation and remodeling during disease and in convalescence. This ability of MMPs to control both the inflammatory response and ECM remodeling during myocarditis makes them potential drug targets. In this review, we analyze the role of MMPs in mediating myocarditis/DCM disease progression, their sex-dependent expression, and their potential as drug targets during viral myocarditis and DCM.