This proposal is being submitted as an application for an AREA award that would allow the Principal Investigator to initiate a new research program related to neuronal survival mechanisms for oxidative stress. As by-products of cellular respiration, a variety of reactive oxygen species (ROS) are formed that can be highly damaging to most types of macromolecules. Several degenerative disorders are associated with oxidative stress and the accumulation of damaged molecules, including aging, Alzheimer's disease, and the damage associated with hypoxia or ischemia/reperfusion events. This research will utilize neurons cultured from an extremely anoxia/reoxygenation resistant vertebrate, the freshwater turtle Trachemys scripta, to test our overarching hypothesis that molecular events induced during anoxia constitutively precondition turtle neurons to withstand reoxygenation stress. These events, including the upregulation of the NFkB and Akt pathways, have been associated with survival or anti-apoptotic pathways in a variety of mammalian cell types. However, their roles are difficult to define in the brain because mammalian neurons are exquisitely sensitive to hypoxia and oxidative stress. Antisense and decoy constructs will be employed to knockout NFkB and/or Akt activities to determine if these pathways are critical to the survival of oxidative stress induced by H202 exposure. Identification of the critical pathways in neuronal survival would be a major contribution to our understanding of the pathology of ischemia/reperfusion events and lend insight into therapeutic approaches for diseases associated with oxidative stress.
Nayak, Gauri; Prentice, Howard M; Milton, Sarah L (2016) Lessons from nature: signalling cascades associated with vertebrate brain anoxic survival. Exp Physiol 101:1185-1190 |
Kesaraju, Shailaja; Schmidt-Kastner, Rainald; Prentice, Howard M et al. (2009) Modulation of stress proteins and apoptotic regulators in the anoxia tolerant turtle brain. J Neurochem 109:1413-26 |
Milton, Sarah L; Prentice, Howard M (2007) Beyond anoxia: the physiology of metabolic downregulation and recovery in the anoxia-tolerant turtle. Comp Biochem Physiol A Mol Integr Physiol 147:277-90 |
Milton, Sarah L; Nayak, Gauri; Kesaraju, Shailaja et al. (2007) Suppression of reactive oxygen species production enhances neuronal survival in vitro and in vivo in the anoxia-tolerant turtle Trachemys scripta. J Neurochem 101:993-1001 |