Original Article

Journal of Molecular Medicine

, Volume 90, Issue 2, pp 127-138

First online:

ZnT-1 protects HL-1 cells from simulated ischemia–reperfusion through activation of Ras–ERK signaling

  • Ofer BeharierAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the NegevCardiac Arrhythmia Research Laboratory, Soroka University Medical Center
  • , Shani DrorAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the NegevCardiac Arrhythmia Research Laboratory, Soroka University Medical Center
  • , Shiri LevyAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the Negev
  • , Joy KahnAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the Negev
  • , Merav MorAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the NegevCardiac Arrhythmia Research Laboratory, Soroka University Medical Center
  • , Sharon EtzionAffiliated withCardiac Arrhythmia Research Laboratory, Soroka University Medical Center
  • , Daniel GitlerAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the Negev
  • , Amos KatzAffiliated withDepartment of Cardiology, Barzilai Medical CenterCardiac Arrhythmia Research Laboratory, Soroka University Medical Center
  • , Anthony J. MuslinAffiliated withCenter for Cardiovascular Research, John Milliken Department of Medicine, Washington University School of Medicine
    • , Arie MoranAffiliated withDepartment of Physiology, Faculty of Health Sciences, Ben-Gurion University of the Negev
    • , Yoram EtzionAffiliated withCardiac Arrhythmia Research Laboratory, Faculty of Health sciences, Ben-Gurion University of the Negev & Soroka University Medical Center Email author 

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Activation of ERK signaling may promote cardioprotection from ischemia–reperfusion (I/R) injury. ZnT-1, a protein that confers resistance from zinc toxicity, was found to interact with Raf-1 kinase through its C-terminal domain, leading to downstream activation of ERK. In the present study, we evaluated the effects of ZnT-1 in cultured murine cardiomyocytes (HL-1 cells) that were exposed to simulated-I/R. Cellular injury was evaluated by lactate dehydrogenase (LDH) release and by staining for pro-apoptotic caspase activation. Overexpression of ZnT-1 markedly reduced LDH release and caspase activation following I/R. Knockdown of endogenous ZnT-1 augmented the I/R-induced release of LDH and increased caspase activation following I/R. Phospho-ERK levels were significantly increased following I/R in cells overexpressing ZnT-1, while knockdown of ZnT-1 reduced phospho-ERK levels. Pretreatment of cells with the MEK inhibitor PD98059 abolished the protective effect of ZnT-1 following I/R. Accordingly, a truncated form of ZnT-1 lacking the C-terminal domain failed to induce ERK activation and did not protect the cells from I/R injury. In contrast, expression of the C-terminal domain by itself was sufficient to induce ERK activation and I/R protection. Interestingly, the C-terminal of the ZnT-1 did not have protective effect against the toxicity of zinc. In the isolated rat heart, global ischemic injury rapidly increased the endogenous levels of ZnT-1. However, following reperfusion ZnT-1 levels were found to be decreased. Our findings indicate that ZnT-1 may have important role in the ischemic myocardium through its ability to interact with Raf-1 kinase.

Keywords

Cardiomyocyte survival Reperfusion injury salvage kinase Raf-1 kinase Extracellular signal-regulated kinase