miRNAs in Cardiomyocyte Apoptosis

This chapter aims to discuss the regulation of cardiomyocyte apoptosis by miRNAs. Apoptosis is an active process that leads to cell death. Unlike necrosis, apoptosis is a complex endogenous gene-controlled event that requires an exogenous signal–stimulated or inhibited by a variety of regulatory factors, such as formation of oxygen free radicals, ischemia, hypoxia, reduced intracellular K+ concentration, and generation of nitric oxide. Apoptosis has been implicated in a variety of human disease including heart disease, Alzheimer’s disease, cancer, etc. To date, no less than 30 individual miRNAs are known to regulate apoptosis. The number in the list is expected to expand quickly with more studies. A number of miRNAs including miR-1, miR-29, and miR-320 are considered proapoptotic miRNAs. The miRNAs identified to date possessing antiapoptotic action include miR- 133, miR-21 and miR-199a. In addition, miR-21 has also been shown to produce proproliferative and antiapoptotic effects in vascular smooth muscle cells. This chapter provides detailed description of these individual miRNAs for their role in cardiomyocyte apoptosis