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Updated: Aug 14, 2026
07:27
Olfactory Assays for Mouse Models of Neurodegenerative Disease
Published on: August 25, 2014
Early olfactory involvement in Alzheimer's disease
S Christen-Zaech1, R Kraftsik, O Pillevuit
1University Institute of Pathology, Division of Neuropathology, 1011, CHUV, Lausanne, Switzerland.
Summary
Alzheimer's disease (AD) significantly damages the olfactory system. This study found a strong association between olfactory bulb and tract changes and cortical degeneration in AD patients, suggesting early olfactory system involvement.
Area of Science:
- Neuropathology
- Neuroscience
- Gerontology
Background:
- Alzheimer's disease (AD) is characterized by severe damage to the olfactory system, including the olfactory bulb.
- Previous research noted early olfactory deficits and AD-type changes in the olfactory bulb.
Purpose of the Study:
- To investigate the occurrence of AD-type degenerative changes in the peripheral olfactory system.
- To determine if olfactory bulb and tract changes correlate with those in the cerebral cortex in AD.
Main Methods:
- Histo- and immunohistochemical analysis of cortical areas, olfactory bulb, and tract in 110 autopsy cases.
- Classification of cases into four groups based on semiquantitative analysis of senile plaques, neurofibrillary tangles, and curly fibers.
Main Results:
- Over 84% of cases with cortical AD-type lesions showed olfactory involvement.
- Significant association (P < 0.001) found between olfactory and cortical degenerative changes in frequency and severity.
- Neurofibrillary tangles and neuropil threads were observed in the olfactory system as early as in the entorhinal cortex.
Conclusions:
- A close relationship exists between olfactory and cortical degenerative changes in Alzheimer's disease.
- Involvement of the olfactory bulb and tract is an early event in the central nervous system degenerative process of AD.
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