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Functions of human olfactory mucus and age-dependent changes
Tomohiro Shirai1, Dan Takase1, Junkichi Yokoyama2,3
1Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan.
Scientific Reports
|January 18, 2023
Summary
Olfactory mucus captures and metabolizes odorants, influencing our sense of smell. Its amount decreases with age, potentially causing olfactory decline.
Area of Science:
- Olfactory Neuroscience
- Human Physiology
- Biochemistry
Background:
- Olfactory sensory neurons detect odorants, but the overlying olfactory mucus remains poorly understood.
- Key aspects like mucus constituents, functions, and individual differences require further investigation.
Purpose of the Study:
- To investigate the molecular composition and functional role of human olfactory mucus.
- To explore the relationship between olfactory mucus properties and odorant detection.
- To identify factors contributing to age-related olfactory decline.
Main Methods:
- Combined collection of olfactory mucus with olfactory psychophysical testing in human participants.
- Analysis of mucus solutes, including proteins, inorganic elements, and xenobiotic metabolism molecules.
- Experimental validation of mucus quantity's impact on odorant detection.
Main Results:
- Human olfactory mucus contains high solute concentrations, enabling odorant capture and metabolism.
- Odorant metabolism by mucus demonstrably alters the sense of smell.
- Olfactory mucus quantity exhibits an age-dependent decrease.
Conclusions:
- Olfactory mucus plays a crucial role in modulating odorant perception through its molecular composition and volume.
- Age-related reduction in olfactory mucus may underlie olfactory decline.
- These findings offer insights into the molecular mechanisms of olfaction and age-associated sensory changes.
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