Early detection of Alzheimer's disease (AD) is a critical factor in combating this devastating disease. The discovery that pathological changes underlying brain degeneration and cognitive loss begin at least 10-20 years before dementia onset has provide an important target for the improvement of disease diagnosis and therapy. The development of biomarkers to detect neuropathology associated with early-stage AD will allow the implementation of preventive treatments much earlier in the pathological process, maximizing treatment efficacy. Notably, olfactory dysfunction precedes symptoms of dementia and memory loss, which has made olfactory tests a commonly used tool in early AD detection. As olfactory decline also occurs in normal aging, an accurate diagnosis of AD relies in the proper distinction between these processes. Interestingly, it is well established that the entorhinal-hippocampal circuit, a key pathway for learning and memory, exhibits early neuropathology in AD, and that olfactory information is relayed to the hippocampus via the entorhinal cortex. Unfortunately, the mechanisms underlying olfactory deficits in AD and natural aging remain largely unknown. Here we propose to unravel the mechanisms by which olfactory information is conveyed to the entorhinal cortex and the adaptations that precede olfactory dysfunction in naturally aging mice and in a transgenic mouse model of AD. To achieve this goal, our team of investigators will use a multidisciplinary approach that combines viral-assisted retrograde labeling, electrophysiology, optogenetics, and behavioral assessment.

Public Health Relevance

Olfactory dysfunction precedes symptoms of dementia and memory loss, making olfactory tests a useful tool in early detection of brain neuropathology, including Alzheimer's disease (AD). Here, we propose to determine the mechanisms by which olfactory information is conveyed to the entorhinal cortex (EC), a key component of brain circuits important for learning and memory, which also exhibits early neuropathology in AD. Importantly, we will determine the neural components of the olfactory bulb-EC circuit, and how the function of this circuit is affected in normal aging and in an animal model of AD.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG049937-04
Application #
9478041
Study Section
Aging Systems and Geriatrics Study Section (ASG)
Program Officer
St Hillaire-Clarke, Coryse
Project Start
2015-04-15
Project End
2020-01-31
Budget Start
2018-05-01
Budget End
2019-03-31
Support Year
4
Fiscal Year
2018
Total Cost
Indirect Cost
Name
University of Maryland College Park
Department
Biology
Type
Earth Sciences/Resources
DUNS #
790934285
City
College Park
State
MD
Country
United States
Zip Code
20742
Jurado, Sandra (2017) AMPA Receptor Trafficking in Natural and Pathological Aging. Front Mol Neurosci 10:446
Hu, Ruilong; Ferguson, Katie A; Whiteus, Christina B et al. (2016) Hyperpolarization-Activated Currents and Subthreshold Resonance in Granule Cells of the Olfactory Bulb. eNeuro 3: