The Role of Proteostasis in the Regulation of Cardiac Intercellular Communication

Given the low mitotic activity of cardiomyocytes, the contractile unit of the heart, these cells strongly rely on efficient and highly regulated mechanisms of protein degradation to eliminate unwanted potentially toxic proteins. This is particularly important in the context of disease, where an impairment of protein quality control mechanisms underlies the onset and development of diverse cardiovascular maladies. One of the biological processes which is tightly regulated by proteolysis mechanisms is intercellular communication. The different types of cells that form the heart, including cardiomyocytes, endothelial cells, fibroblasts, and macrophages, can communicate directly, through gap junctions (GJ) or tunneling nanotubes (TNT), or at long distances, via extracellular vesicles (EV) or soluble factors.