TY - JOUR
T1 - The Effects of the Levels of Hypoxia in the Olfactory Nervous System in Mouse Model
AU - Kim, Boo Young
AU - Park, Ju Yeon
AU - Bae, Jung Ho
N1 - Funding Information:
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2021R1I1A1A01044354).
Publisher Copyright:
© The Author(s) 2023.
PY - 2023/9
Y1 - 2023/9
N2 - Purpose: Intermittent hypoxia (IH) results in low-grade inflammation, sympathetic overactivity, and oxidative stress. However, the specific effects of IH on olfaction have not yet been directly assessed and remain unclear. Therefore, the purpose of this study was to investigate the cytotoxic effects of IH exposure on the mouse olfactory epithelium and the relationship between the concentration of hypoxia and the degree of destruction of the olfactory system. Methods: Thirty mice were randomly divided into six groups: control (room air for 4 weeks), recovery control (room air for 5 weeks), IH 5% oxygen concentration, IH 7% oxygen concentration, recovery 5% hypoxia, and recovery 7% hypoxia groups. Mice in the two hypoxia groups were exposed to 5% and 7% oxygen for 4 weeks. Mice in the two recovery groups were exposed to room air for 1 week after 4 weeks of hypoxia period. Results: Based on, the olfactory marker protein (OMP), Olfr1507, ADCY3, and GNAL were lower, whereas S100b and NGFRAP1 messenger RNA (mRNA) levels were higher in the 5% hypoxia group than those in the control group in the olfactory neuroepithelium. In the brain tissue, the changes in RNA analysis for Olfr 1507, OMP, ADCY, and GNAL mRNA were not typical. However, NeuN and GFAP levels were decreased under 5% hypoxia in the brain tissue. In the recovery state, CNPase, S100b and NeuN levels were increased significantly in both the olfactory neuroepithelium and brain tissue in the 5% hypoxia group. The change in RNA activity in PCR was much higher in the 5% hypoxia group than in the 7% hypoxia group. Conclusions: Our findings suggest that IH damages the olfactory neuroepithelium and brain tissue in mouse model. The activity of olfactory marker genes and neurogenesis in the olfactory neuroepithelium were decreased. The levels of oxygen may be affect changes in the olfactory neuroepithelium. The olfactory ensheathing cell may be a major factor in the recovery of the olfactory neuroepithelium.
AB - Purpose: Intermittent hypoxia (IH) results in low-grade inflammation, sympathetic overactivity, and oxidative stress. However, the specific effects of IH on olfaction have not yet been directly assessed and remain unclear. Therefore, the purpose of this study was to investigate the cytotoxic effects of IH exposure on the mouse olfactory epithelium and the relationship between the concentration of hypoxia and the degree of destruction of the olfactory system. Methods: Thirty mice were randomly divided into six groups: control (room air for 4 weeks), recovery control (room air for 5 weeks), IH 5% oxygen concentration, IH 7% oxygen concentration, recovery 5% hypoxia, and recovery 7% hypoxia groups. Mice in the two hypoxia groups were exposed to 5% and 7% oxygen for 4 weeks. Mice in the two recovery groups were exposed to room air for 1 week after 4 weeks of hypoxia period. Results: Based on, the olfactory marker protein (OMP), Olfr1507, ADCY3, and GNAL were lower, whereas S100b and NGFRAP1 messenger RNA (mRNA) levels were higher in the 5% hypoxia group than those in the control group in the olfactory neuroepithelium. In the brain tissue, the changes in RNA analysis for Olfr 1507, OMP, ADCY, and GNAL mRNA were not typical. However, NeuN and GFAP levels were decreased under 5% hypoxia in the brain tissue. In the recovery state, CNPase, S100b and NeuN levels were increased significantly in both the olfactory neuroepithelium and brain tissue in the 5% hypoxia group. The change in RNA activity in PCR was much higher in the 5% hypoxia group than in the 7% hypoxia group. Conclusions: Our findings suggest that IH damages the olfactory neuroepithelium and brain tissue in mouse model. The activity of olfactory marker genes and neurogenesis in the olfactory neuroepithelium were decreased. The levels of oxygen may be affect changes in the olfactory neuroepithelium. The olfactory ensheathing cell may be a major factor in the recovery of the olfactory neuroepithelium.
KW - brain
KW - hypoxia
KW - olfaction
KW - olfactory dysfunction
KW - olfactory epithelium
KW - olfactory regeneration
KW - olfactory system
UR - http://www.scopus.com/inward/record.url?scp=85162900977&partnerID=8YFLogxK
U2 - 10.1177/19458924231184332
DO - 10.1177/19458924231184332
M3 - Article
C2 - 37350017
AN - SCOPUS:85162900977
SN - 1945-8924
VL - 37
SP - 575
EP - 585
JO - American Journal of Rhinology and Allergy
JF - American Journal of Rhinology and Allergy
IS - 5
ER -