Overexpression of vasostatin-1 protects hypoxia/reoxygenation injuries in cardiomyocytes-endothelial cells transwell co-culture system

Vasostatin-1 (VS-1) plays important roles in myocardial ischemia/reperfusion injury. We have explored the protective effects of VS-1 on cardiomyocytes using cardiomyocyte-endothelial cells Transwell Co-culture System. Cardiomyocytes and rat aortic endothelial cells (RAECs) were prepared from ventricles and thoraco-abdominal aorta of Sprague-Dawley rats. The experiment used cardiomyocytes alone culture group (C) and cardiomyocytes-RAECs co-culture group (T), each with three subgroups: C-Ad-Null, C-Ad-VS-1, C-Hb (Ad-VS-1+NO scavenger Hb), or T-Ad-Null, T-Ad-VS-1 transfection, T-Hb. After 48h incubation, all groups were treated with hypoxia for 60min and then reoxygenated for 120min. We also investigated endothelial cells-mediated cardiomyocytes protection. RAECs were treated with hypoxia for 30min and reoxygenated with normal cardiomyocytes for 120min. The cardiomyocytes apoptosis rate, aspartate aminotransferase (AST) and creatine kinase isozyme MB (CK-MB) were recorded. As expected, cardiomyocytes apoptosis, AST and CK-MB were significantly increased in the T-Ad-Null group than in the C-Ad-Null group. VS transfection significantly reduced these levels. However, apoptosis, AST and CK-MB levels were increased again after Hb treatment, returning to the similar level of the C-Ad-null group in the C-Hb group, but still significantly lower in the T-Hb group compared with the T-Ad-null group. RAEC injury caused cardiomyocyte injury, and VS-1 transfection of the RAEC decreased apoptosis and the levels of AST and CK-MB. The findings suggest that VS-1 exerts protective effects on the cardiomyocytes directly or indirectly by cardiomyocyte-endothelial cells interaction.