The most significant etiological factor in Alzheimer's disease (AD) is age. But how does age contribute to the cellular and molecular pathology of AD? It is hypothesized that hippocampal neurons from aged animals are more susceptible to Abeta than younger neurons due to a decreased ability to generate the energy needed to control ion fluxes in this region of the AD brain. Novel techniques for the culture of aged neurons in serum-free medium have been developed recently by the PI, enabling examination of age-related cellular responses. New data have been obtained that subtoxic levels of lactate acidosis alter APP processing resulting in deposition of more amyloidogenic fragments. Also, neurons from aged rats are more susceptible to Abeta, lactate acidosis, and glutamate toxicity and fail to increase ATP levels to meet demands of increased ionic fluxes. Using neurons cultured from adult and aged rats, the first aim is to compare responses to fibrillar Abeta in terms of intracellular calcium, pH, and viability. Also regional AD pathology will be examined by comparing responses to Abeta in hippocampal with cerebellar granule neurons.
The second aim examines the impact of glutamate and lactate acidosis on Abeta toxicity.
The third aim examines whether age-related changes in susceptibility to Abeta are accounted for by declines in energy production, free radical damage, or induction of apoptosis. These studies hope to provide a better understanding of the age-related responses of cultured neurons to stressors thought to be important in the AD brain.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
3R01AG013435-03S1
Application #
6051450
Study Section
Neurological Sciences Subcommittee 1 (NLS)
Project Start
1997-04-01
Project End
2001-03-31
Budget Start
1999-04-15
Budget End
2000-03-31
Support Year
3
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Southern Illinois University School of Medicine
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
City
Springfield
State
IL
Country
United States
Zip Code
62794
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Patel, Jigisha R; Brewer, Gregory J (2008) Age-related changes to tumor necrosis factor receptors affect neuron survival in the presence of beta-amyloid. J Neurosci Res 86:2303-13

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