The role of ethanol in Nrf2-ARE mediated neuroprotection.

University Of Texas Hlth Science Center, San Antonio TX

Investigators

Abstract

[unreadable] DESCRIPTION (provided by applicant): This proposal is formatted with three Specific Aims designed to determine the mechanisms by which ethanol induces Nrf2 mediated ARE activation of genes which regulate cellular glutathione (GSH) levels and are components of the neuroprotective Y-glutamyl cycle. It is hypothesized that ethanol induces activation of an astrocyte Nrf2-ARE dependant neuroprotective pathway which acts as a cellular redox switch to up-regulate components of the y-glutamyl cycle thereby controlling GSH homeostasis in neurons. The overall objective of this proposal is to elucidate mechanisms underlying protection against ethanol- induced neuroapoptosis in the developing brain. Components of the neuroprotective Y-glutamyl cycle are present on astrocytes and mediate neuron GSH-homeostatic machinery which can be highly regulated to enhance its neuroprotective capacity. The importance of this pathway is that it is a rapid response mechanism by which astrocyte components of the Y-glutamyl cycle can be augmented for neuroprotection. Regulation and/or manipulation of systems responsible for coordinated enhancement of astrocyte glutathione-homeostatic machinery which provides neuroprotection, can be further exploited to protect against a myriad of diseases in which neuronal oxidative damage is implicated. Specific Aim I will extend preliminary data to determine the underlying mechanism of ethanol induced Nrf2 protein. Specific Aim II will address the hypothesis that ethanol induces the dissociation of the Nrf2/Keap1 complex and elucidate the specific mechanisms by which this occurs. Specific Aim III will extend preliminary data to characterize ethanol's effect on Nrf2-ARE binding and activation, and ultimately neuroprotection. This aim will also extend in vitro studies to the whole animal. We will utilize an in-vivo imaging technique that will allow for monitoring of real time effects in the living cerebral cortex. The significance of the proposed studies is to define the underlying mechanisms by which the neuroprotective capacity of astrocytes can be enhanced to protect against ethanol mediated oxidative stress and apoptotic death. Ultimately, sites of augmentation of anti-oxidant pathways that are neuroprotective can be translated into points of clinical intervention. The specific aims described above will characterize a critical neuroprotective pathway that impacts a broad range of neuropathologies connected to oxidative stress. These include cancer, Alzheimer's disease, Parkinson's disease, stroke, and aging. [unreadable] [unreadable] [unreadable]