The long range goal is intervention to delay or prevent cognitive decline associated with unsuccessful aging, in order to improve the health and well-being of older Americans. The incidence of Alzheimer's disease is projected to increase dramatically, with the greatest prevalence in women. Synaptic loss contributes to memory impairments and estrogen (E2) promotes synaptogenesis and memory. Thus, E2 treatment could have a major impact on public health. However, the efficacy of E2 is greatly reduced if therapy occurs several years after the onset of menopause, suggesting a temporally limited therapeutic window. Evidence indicates estrogen receptor (ER) expression and ER polymorphisms contribute to a variety of hormone sensitive diseases, including cognitive decline. We hypothesize that differential expression of ER1 and ER2 interacts with the level of E2 to contribute to 1) the etiology of age-related memory deficits, 2) loss of E2 mediated synaptogenesis, and 3) the closing of the E2 therapeutic window.
Aim 1 will combine aging ER1 and ER2 knockout mice with viral vectors to influence ER expression and systematically perform behavioral, molecular, and electrophysiological assays to test the hypothesis.
Aim 2 will employ hippocampal viral delivery vectors to increase or decrease ER1 or ER2 in young, middle-age, and aged rats, and will use behavioral and molecular assays to test the hypothesis that shifting the ratio of ER1/ER2 expression rejuvenates hippocampal function.
Aim 3 will employ viral vectors to alter the expression of ER1 or ER2, and will test the hypothesis that ER expression contributes to age-related changes in rapid E2 signaling. Knockout mice and viral vector gene delivery provide novel approaches to test the hypothesis that ER expression is a contributing factor for hippocampal aging. Together, these studies will determine whether altering the level of ER1 or ER2 expression is important for age-related memory decline, E2-induced synaptogenesis, and closing of the E2 therapeutic window, and will provide the groundwork for development of therapies to slow or prevent cognitive decline associated with aging and age-related diseases.

Public Health Relevance

Research to reduce cognitive decline is crucial, given the burgeoning number of elderly, in which 3 in 10 will display serious cognitive decline due to age and Alzheimer's disease. Women exhibit greater risk for cognitive decline and comprise greater than 60% of the Alzheimer population. These studies will provide a scientific foundation for interventions to avert the impending wave of cognitively impaired seniors.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG037984-14
Application #
8707918
Study Section
Neurobiology of Learning and Memory Study Section (LAM)
Program Officer
Wagster, Molly V
Project Start
2010-09-15
Project End
2016-05-31
Budget Start
2014-06-01
Budget End
2015-05-31
Support Year
14
Fiscal Year
2014
Total Cost
$290,997
Indirect Cost
$85,997
Name
University of Florida
Department
Neurosciences
Type
Schools of Medicine
DUNS #
969663814
City
Gainesville
State
FL
Country
United States
Zip Code
32611
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Bean, Linda A; Ianov, Lara; Foster, Thomas C (2014) Estrogen receptors, the hippocampus, and memory. Neuroscientist 20:534-45
Brim, B L; Haskell, R; Awedikian, R et al. (2013) Memory in aged mice is rescued by enhanced expression of the GluN2B subunit of the NMDA receptor. Behav Brain Res 238:211-26