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Updated: Dec 19, 2025
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A Free-breathing fMRI Method to Study Human Olfactory Function
Published on: July 30, 2017
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Alzheimer's Disease: What Can We Learn From the Peripheral Olfactory System?
Michele Dibattista1, Simone Pifferi2, Anna Menini2
1Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari A. Moro, Bari, Italy.
Frontiers in Neuroscience
|June 9, 2020
Summary
Olfactory system impairments, including the olfactory epithelium and bulb, are early indicators in Alzheimer's disease (AD) progression. Studying these changes in mice offers insights into AD pathogenesis and early molecular mechanisms.
Area of Science:
- Neuroscience
- Pathophysiology
- Olfactory System Research
Background:
- Olfactory dysfunction, characterized by a decreased ability to smell, is an early symptom in neurodegenerative disorders like Parkinson's disease (PD) and Alzheimer's disease (AD).
- The olfactory system, encompassing olfactory neurons and the olfactory bulb (OB), offers a unique peripheral window into central nervous system (CNS) physiology and pathophysiology.
- Regenerative properties of olfactory neurons present diverse cellular mechanisms potentially altered in AD pathogenesis.
Purpose of the Study:
- To review pathophysiological changes in the peripheral olfactory system during Alzheimer's disease progression in mouse models.
- To highlight the sensitivity of the olfactory epithelium and olfactory bulb to AD-related protein and enzyme alterations.
- To explore the potential of olfactory impairments as early biomarkers for understanding AD molecular mechanisms.
Main Methods:
- Review of existing literature focusing on mouse models of Alzheimer's disease.
- Analysis of studies examining changes in the olfactory epithelium and olfactory bulb.
- Correlation of olfactory system alterations with known AD pathogenesis markers and proteins.
Main Results:
- The olfactory epithelium and olfactory bulb exhibit particular sensitivity to changes in proteins and enzymes implicated in Alzheimer's disease pathogenesis.
- Alterations in odorant receptor expression, neurogenesis, neurodegeneration, axonal targeting, and synaptogenesis within the olfactory system are observed.
- These peripheral olfactory changes occur in conjunction with typical pathological hallmarks of AD.
Conclusions:
- The olfactory system, particularly the olfactory epithelium and olfactory bulb, serves as a sensitive indicator of early Alzheimer's disease progression.
- Investigating olfactory impairments in mouse models can elucidate molecular mechanisms underlying the initial phases of AD pathology.
- Olfactory dysfunction may represent a valuable, non-invasive biomarker for early AD detection and understanding.
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