Using proteomics to uncover extracellular matrix interactions during cardiac remodeling.

The left ventricle (LV) responds to a myocardial infarction (MI) with an orchestrated sequence of events that results in fundamental changes to both the structure and function of the myocardium. This collection of responses is termed LV remodeling. Myocardial ischemia resulting in necrosis is the initiating event that culminates in the formation of an extracellular matrix (ECM)-rich infarct scar that replaces necrotic myocytes. While the cardiomyocyte is the major cell type that responds to ischemia, infiltrating leukocytes and cardiac fibroblasts coordinate the subsequent wound healing response. The matrix metalloproteinase (MMP) family of enzymes regulates the inflammatory and ECM responses that modulate scar formation. Matridomics is the proteomic evaluation focused on ECM, while degradomics is the proteomic evaluation of proteases as well as their inhibitors and substrates. This review will summarize the use of proteomics to better understand MMP roles in post-MI LV remodeling.