Dominguez-Rodriguez, Alejandro , Mayoral-Gonzalez, Isabel , Avila-Medina, Javier , de Rojas-de Pedro, Eva S. , CALDERON SANCHEZ, EVA MARIA, Diaz, Ignacio , Hmadcha, Abdelkrim , Castellano, Antonio , Rosado, Juan A. , Benitah, Jean-Pierre , Gomez, Ana M. , ORDÓÑEZ FERNÁNDEZ, JOSÉ ANTONIO, Smani, Tarik
No
Front. Physiol.
Article
Científica
3.201
03/07/2018
000437210700001
Aims: Urocortin-2 (Ucn-2) is a potent cardioprotector against Ischemia and Reperfusion (I/R) injuries. However, little is known about its role in the regulation of intracellular Ca2+ concentration ([Ca2+](i)) under I/R. Here, we examined whether the addition of Ucn-2 in reperfusion promotes cardioprotection focusing on {[Ca2+](i) handling. Methods and Results: Cardiac Wistar rat model of I/R was induced by transient ligation of the left coronary artery and experiments were conducted 1 week after surgery in tissue and adult cardiomyocytes isolated from risk and remote zones. We observed that I/R promoted significant alteration in cardiac contractility as well as an increase in hypertrophy and fibrosis in both zones. The study of confocal [Ca2+](i) imaging in adult cardiomyocytes revealed that I/R decreased the amplitude of [Ca2+](i) transient and cardiomyocytes contraction in risk and remote zones. Interestingly, intravenous infusion of Ucn-2 before heart's reperfusion recovered significantly cardiac contractility and prevented fibrosis, but it didn't affect cardiac hypertrophy. Moreover, Ucn-2 recovered the amplitude of [Ca2+](i) transient and modulated the expression of several proteins related to [Ca2+](i) homeostasis, such as TRPC5 and Orai1 channels. Using Neonatal Rat Ventricular Myocytes (NRVM) we demonstrated that Ucn-2 blunted I/R-induced Store Operated Ca2+ Entry (SOCE), decreased the expression of TRPC5 and Orai1 as well as their interaction in reperfusion. Conclusion: Our study provides the first evidences demonstrating that Ucn-2 addition at the onset of reperfusion attenuates I/R-induced adverse cardiac remodeling, involving the [Ca2+](i) handling and inhibiting the expression and interaction between TRPC5 and Orai1.
Urocortin-2; ischemia and reperfusion; adverse remodeling; Ca2+ dysregulation; store operated Ca2+ channels