New work by researchers in Spain indicates that exosome-mediated communication between cardiomyocytes (CMs) and endothelial cells (ECs) establishes a functional relationship that could have potential implications for the induction of local neovascularization during acute situations such as cardiac injury. The researchers noted that it has been well known that CMs and ECs have an intimate anatomical relationship that is essential for maintaining normal development and function in the heart. However, the scientists said that little had been known about about the mechanisms that regulate cardiac and endothelial crosstalk, particularly in situations of acute stress when local active processes are required to regulate endothelial function. Consequently, the research team examined whether CM-derived exosomes could modulate endothelial function. Under conditions of glucose deprivation, immortalized H9C2 CMs increase their secretion of exosomes. CM-derived exosomes are loaded with a broad repertoire of miRNAs and proteins in a glucose-availability-dependent manner. Gene Ontology (GO) analysis of exosome cargo molecules identified an enrichment of biological process that could alter EC activity. The researchers observed experimentally that addition of CM-derived exosomes to ECs induced changes in the transcriptional activity of pro-angiogenic genes. In addition, the scientists demonstrated that incubation of H9C2-derived exosomes with ECs induced proliferation and angiogenesis in the ECs. Thus, they concluded that exosome-mediated communication between CMs and ECs establishes a functional relationship that could have potential implications for the induction of local neovascularization during acute situations such as cardiac injury.Login Or Register To Read Full Story