The experiments in this project use innovative gene delivery techniques and a multipronged approach to assess the fundamental role of astrocyte activation in neurologic function in an intact mouse model of Alzheimer's disease (AD). Studies use adeno-associated virus vectors (AAV) bearing the astrocyte-specific promoter Gfa2 to target the protein phosphatase calcineurin (CN) and NFAT transcription factors in astrocytes of wild-type and APP/PS1 mice. AAV-Gfa2 vectors are bilaterally delivered to the hippocampus at different ages/disease stages and mice are assessed on different AD biomarkers.
In Aim 1, cognitive status is assessed using the active avoidance task, while synaptic function is evaluated using hippocampal slice electrophysiology and Western blot measures of synaptic proteins.
In Aim 2, hippocampal glutamate regulation is investigated using ceramic enzyme-based microelectrode arrays and measures of glutamate transporter levels.
In Aim 3, levels of glial activation and neuroinflammation are determined with immunohistochemical (IHC) analyses and assessment of cytokine levels using Multiplex ELISAs.
In Aim 4, IHC is used to determine the extent of A? deposition, while ELISAs are used to quantify levels of A?40 and A?42 in soluble and insoluble hippocampal tissue fractions, and Westerns used to assess BACE protein expression. AAV-Gfa2 vectors encode either potent inhibitors or activators of CN/NFAT signaling and therefore will determine the necessity and sufficiency of this astrocytic pathway in driving and/or maintaining neurologic dysfunction in AD mice. These studies provide a highly novel approach to the study of activated astrocytes and could have a major impact on the development of treatment strategies for AD and other neurodegenerative conditions.

Public Health Relevance

Increasing evidence implicates activated astrocytes in a variety of neurodegenerative conditions, including Alzheimer's disease (AD). However, these cells are difficult to target selectively with therapeutics. In this project, we use cutting-edge adeno associated virus vectors to selectively prevent astrocyte activation and improve neurologic function in intact AD model mice. This approach could emerge as a new treatment strategy for AD and other neurodegenerative disorders.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG027297-08
Application #
8657965
Study Section
Cell Death in Neurodegeneration Study Section (CDIN)
Program Officer
Wise, Bradley C
Project Start
2005-12-01
Project End
2017-03-31
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
8
Fiscal Year
2014
Total Cost
$299,613
Indirect Cost
$94,613
Name
University of Kentucky
Department
Other Health Professions
Type
Schools of Medicine
DUNS #
939017877
City
Lexington
State
KY
Country
United States
Zip Code
40506
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