salubrinal and Coronary-Disease

Previous studies have suggested an association of hyperhomocysteinemia-induced vascular pathology with enhanced apoptotic potential of endothelial progenitor cells in patients with coronary heart disease. Our results indicate that 500 µmol/L homocysteine induced endothelial progenitor cell apoptosis and activation of caspase-3, both of which were abolished by 100 µmol/L and 200 µmol/L salubrinal, an agent that prevents endoplasmic reticulum stress-induced apoptosis. The addition of 500 µmol/L homocysteine caused a release of Ca(2+) from intracellular stores, and enhanced phosphor-eukaryotic initiation factor 2α phosphorylation at Ser51 and the expression of a glucose-regulated protein of 78 kDa and a C/EBP homologous protein independently of extracellular Ca(2+). These effects of homocysteine on endothelial progenitor cells were significantly greater in patients with coronary heart disease than in healthy donors. These findings suggest that homocysteine induces endoplasmic reticulum stress-mediated activation of caspase-3 in endothelial progenitor cells, an event that is enhanced in patients with coronary heart disease. Furthermore, enhanced endoplasmic reticulum stress-mediated activation of caspase-3 in endothelial progenitor cells might be involved in hyperhomocysteinemia-associated vascular pathology.

Topics: Animals; Apoptosis; Blood Donors; Calcium Signaling; Caspase 3; Cell Line; Cinnamates; Coronary Disease; Endoplasmic Reticulum; Endothelial Cells; Homocysteine; HSP70 Heat-Shock Proteins; Humans; Male; Membrane Proteins; Oxidative Stress; Phosphorylation; Stem Cells; Thiourea