John G. Edwards, Ph.D.
Associate Professor of Physiology
Department of Physiology
Basic Sciences Building
New York Medical College
Valhalla, NY 10595
Cardiovascular disease is the leading cause of mortality in noninsulin-dependent diabetes mellitus patients. Diabetic cardiomyopathy is associated with abnormal cardiac function, increased apoptosis and loss of cardiac mass. Mitochondrial dysfunction has a significant role in the development and complications of diabetic cardiomyopathy. Diabetes elevates oxidative stress, which contributes to mitochondrial dysfunction. Mitochondrial DNA (mtDNA) is particularly susceptible to damage, and the laboratory group has demonstrated that increased mtDNA mutations are concomitant with the oxidative stress associated with hyperglycemia. The group is examining whether diabetic-induced alterations in mitochondrial topoisomerase activity are the underlying mechanism for mtDNA damage and mitochondrial dysfunction that is antecedent to heart failure. A second project will establish whether cardiac progenitor cells are more sensitive to chronic elevations in oxidative stress than cardiomyocytes. Taking a longer view, identifying the pathology of cardiac stem cells as a consequence of diabetes will alter the clinical paradigm for the management of diabetes. It will provide a basis for development of new studies that focus on the protection of stem cells as a real target for clinical management.
Post Graduate Studies: University of Arizona
Einstein College of Medicine
Graduate Degree: Ph.D.
Graduate Degree Institution: University of Iowa
Undergraduate Institution: Queen’s University
Medikayala S., B. Piteo, X. Zhao, & J. G. Edwards: Chronically elevated glucose compromises myocardial mitochondrial DNA integrity by alteration of mitochondrial topoisomerase function. Amer. Jour, Physiology; Cell; 300(2): C338-348, 2011
Gupte S., N. Labinskyy, A. Csiszar, Z. Ungvari & J. G. Edwards : Role of NAD(P)H oxidase in superoxide generation and endothelial dysfunction in diabetic Goto-Kakizaki (GK) rats. PLOSONE Jul 26;5(7):e11800, 2010
Kalogiannis, M., Grupke, S.L., Potter, P.E.; Edwards, J.G., Chemelli, R.M., Kisanuki, Y.Y., Yanagisawa, M. and Leonard, C.S.: Narcoleptic orexin receptor knockout mice express enhanced cholinergic properties in laterodorsal tegmental neurons. European Journal of Neuroscience 32(1):130-42, 2010
Pepe M., Mohammed Mamdani, Lorena Zentilin, Anna Csiszar, Khaled Qanud, Serena Zacchigna, Zoltan Ungvari, Uday Puligadda, Silvia Moimas, Xiaobin Xu, John G. Edwards, Thomas H. Hintze, Mauro Giacca, Fabio A. Recchia: Intramyocardial VEGF-B167 Gene Delivery Delays the Progression Towards Congestive Failure in Dogs With Pacing-Induced Dilated Cardiomyopathy. Circulation Res. 106: 1893-1903, 2010
Edwards J.G.: Determination of mitochondrial DNA error rate by quantitative realtime PCR. Mitochondrion 9:31-35, 2009
Grijalva J., Steven Hicks S., Zhao X., Medikayala S., Kaminski P, Wolin M.., & John G. Edwards: Exercise training enhanced myocardial endothelial nitric oxide synthase (eNOS) function in diabetic Goto-Kakizaki (GK) rats. Cardiovascular Diabetology 7:34, 2008