Joan McEwen, Ph.D. is a Research Associate Professor in the Department of Geriatrics at UAMS. She researches mechanistic links between mitochondrial metabolism and cellular oxidative and nitrosative stress. The metabolic energy required for growth, repair, and survival of eukaryotic cells is predominantly generated by mitochondria, but an unavoidable side reaction of oxidative metabolism is production of free radicals, thus contributing to cellular oxidative stress and aging. Cellular nitrosative stress, caused by nitric oxide, includes direct inhibition of mitochondrial enzymes with cell death as the end result, if the stress is not appropriately combatted. For her studies, Dr. McEwen uses two model organisms, Baker’s yeast (Saccharomyces cerevisiae) and Histoplasma capsulatum.
Johnson, CH, Klotz, MG, York, JL, Kruft, V and McEwen, JE. Redundancy, phylogeny and differential expression of Histoplasma capsulatum catalases. Microbiology, 2002. 148: 1129-1142.
Johnson CH, Prigge JD, Warren AD, McEwen, JE. 2003. Characterization of an alternative oxidase activity of Histoplasma capsulatum. Yeast 20:381-388.
Missal, T.A., Lodge, J.K., and McEwen, J.E. 2004. Mechanisms of resistance to oxidative and notrosative stress: Implications for fungal survival in mammalian hosts. Eukaryotic Cell 3: 835-846.
McEwen, J.E., Zimniak, P., Mehta, J.L., and Reis, R.J. 2005. Molecular pathology of aging and its implications for senescent coronary atherosclerosis. Current Opinion in Cardiology 20: 399-405.
