Dr. Jitka Virag, Ph.D.

Assistant Professor Department of Physiology

Assistant Professor
Brody School of Medicine
East Carolina State University, Greenville, NC
Research focus: Repair of the infarcted heart

Research Scientist (September 2004 - October 2005)
Universities Space Research Association, Division of Space Life Sciences, Center for Advanced Space Studies
Cardiovascular Laboratory, Johnson Space Center, NASA, Houston, TX
Research focus: The Effects of Microgravity on the Heart

Senior Fellow (1999-2004)
University of Washington, Seattle, WA
Advisor: Dr. Charles E. Murry, M.D., Ph.D.
Post-doctoral research project: Murine Myocardial Infarct Repair.
   
Doctor of Philosophy, Physiology (1994 –1999)
Louisiana State University Medical Center (LSUMC), New Orleans, LA
Advisor: Dr. Kathleen H. McDonough, Ph.D.
Dissertation title: Mechanisms of Sepsis-Induced Dysfunction and Protection from Ischemia/Reperfusion Injury

Bachelor of Science with Honors, Biology (1989 -1993)
Queen's University, Kingston, Ontario, Canada
Advisor: David Layzell, Ph.D.
Research project: Nitrogenase Activity in Soybean Root Nodules

Heart failure is a significant public health problem.  Since the heart lacks sufficient regenerative potential to recover from an ischemic event, efforts are being made to prevent excessive damage and alleviate subsequent remodeling and heart failure through the use of gene or protein therapy alone or in conjunction with cell/tissue grafting.  We employ the murine model of myocardial infarction, to study acute ischemia/reperfusion injury as well as chronic remodeling in non-reperfused myocardial infarction.  This is a very valuable tool that can be used to investigate factors that mediate injury, determinants of the extent of remodeling, and interventions that can impede or even halt these processes once they have begun.  

We are currently studying two lines of research: the influence of circadian rhythm genes and the ephrinA/EphA family of receptors tyrosine kinases on modulation of infarct size.  There are clear variations in circadian rhythms in the incidence of cardiovascular disease and the risk of cardiovascular events increases when rhythms are disrupted.  The genes that govern diurnal rhythms have recently been shown to exist in myocardial tissue and are involved in metabolism and contractile function.  Specifically, we are exploring the mechanism by which functional deletion of the mPer2 gene reduces infarct size. This information will hopefully be useful in reducing the incidence of heart disease in susceptible populations (e.g. shift workers, jet lag).  

The Eph receptors (Eph = erythropoietin-producing hepatocellular) and, their cognate ligands the ephrins (contraction of "Eph receptor interacting proteins" and after the Greek word "ephoros" meaning overseer or controller), the largest family of receptor tyrosine kinases, have been shown to contribute to differentiation, proliferation, and migration of various cell types during development. In particular, ephrinA1/EphA receptor tyrosine kinase signaling is essential to vascular growth in development as well as in adult tumor angiogenesis.  The expression pattern of EphrinA1 and the eight EphA receptors is completely unknown in the adult heart, as well as in response to myocardial injury.  Investigating the involvement of ephrinA1/EphA receptors in inflammation, cell kinetics, angiogenesis, and scar formation in post-MI myocardium will provide the framework from which to extrapolate the potential capacity of selectively modulating ephrinA1 and EphA receptors to improve myocardial infarct healing.  

We examine the heart from the level of cardiac function using echocardiography and pressure-volume loops, to the gross level histologically, to the protein and gene level using immunohistochemistry, proteomic analyses, and RT-PCR. We also perform cell culture and molecular assays to resolve mechanistic questions. Those interested may inquire about possible openings in the laboratory.

Active

North Carolina Biotechnology Center Biotechnology Research Grant. Project: Intramyocardial EphrinA1-Fc Reduces Myocardial Infarct Injury. PI: Jitka Virag, Award Amount: $75,000; Sept 2012 - Mar 2014
ECU news: http://www.ecu.edu/cs-admin/news/virag.cfm
Local news: http://www.reflector.com/node/1238717

Past (3 years)

Intramural East Carolina Diabetes and Obesity Institute funds, East Carolina University. Project: Myocardial EphrinA/EphA in Diabetes and Infarction. PI: Jitka Virag, Award Amount: $18,500; Nov 2010-May 2012

Office of Technology Transfer Ignition Funds, East Carolina University.Project: EphrinA1-Fc Attenuates Ischemic Injury. PI: Jitka Virag, Award Amount: $7,300; Dec 2011-Dec 2012