Regulatory Roles of the Ubiquitin-Proteasome System in Cardiomyocyte Apoptosis

W.      Sohns; T.   A.B.   van Veen; M.   A.G.   van der Heyden

doi:10.2174/156652410791065426

Abstract

Cardiovascular disease is the leading cause of death in the western world. The major contributor of all cardiovascular deaths is myocardial infarction, which often progresses into end-stage heart failure. The loss of cardiomyocytes is a key problem in the development of cardiovascular disease. Two main processes mediate cardiomyocyte loss: necrosis and apoptosis. In contrast to necrosis, apoptosis is a well regulated process essential in normal development and tissue homeostasis. Tight regulation of this process is crucial, especially in post mitotic cells lacking regenerative capacity, like cardiomyocytes. The ubiquitin-proteasome system, accounting for 80 to 90% of intracellular protein degradation, appears to be involved in the regulation of apoptosis. In this process, regulation is performed through the degradation of pro- and anti-apoptotic proteins involved in cell cycle control and specific apoptotic pathways. On the one hand, disturbances in this normally well regulated process are associated with a number of cardiovascular diseases. On the other hand, proteasomal dysfunction may result from ischemia, hypertrophy and heart failure, and a number of cardiomyopathies. This paper reviews the current knowledge on the role of the ubiquitin-proteasome systemmediated regulation of cardiomyocyte apoptosis in cardiovascular disease. Finally, within the ubiquitinproteasome system new molecular targets for treatment of cardiovascular disease are suggested.

Keywords: Heart, apoptosis, ubiquitination, ubiquitin-proteasome system, cardiovascular disease, p53