Abstract
Hexanal is a 6-carbon aldehyde that smells like green leaves and urine to mammals. However, its physiological effects remain unclear. In particular, the effects of hexanal inhalation on the central nervous system have not been clarified. We investigated hexanal inhalation in mice and conducted a series of behavioral experiments to examine the neuropsychological effects of hexanal. After inhaling hexanal emissions for 30 min, mice were subjected to an open field test, a hot plate test, a grip strength test, an elevated plus maze test, a Y-maze test, a tail suspension test, and a forced swim test to examine the effects of hexanal odor on mouse behavior. Compared to controls, mice that inhaled hexanal exhibited reduced anxiety-like behavior in the elevated plus maze test. In addition, mice that inhaled hexanal displayed significantly improved spatial cognitive ability in the Y-maze test. However, in some behavioral experiments there was no significant difference between control mice and mice that inhaled hexanal. The results of this study suggest that hexanal inhalation causes anxiolytic effects and improves cognitive function in mice. These findings may have implications for safety management procedures and determining the effective use of household goods containing hexanal, though further work is required.
Funding source: Yakumo Foundation for Environmental Science
Acknowledgments
We thank Kawasaki Medical School Central Research Institute for providing instruments to support this study. The authors would like to thank Editage (www.editage.com) for English language editing.
Author contributions: All authors had full access to all study data and take full responsibility for the integrity of the data and accuracy of the data analysis. Study concept and design: H.U., A.S., and M.O. Data acquisition: H.U., S.S., and Y.T. Data analysis and interpretation: H.U., A.S., and S.S. Drafting of the manuscript: H.U., A.S., Y.T., and M.O. Critical revision of the manuscript for important intellectual content: A.S., S.M., N.K., K.W., Y.T., Y.M., M.O., and T.I. Statistical analyses: H.U and S.S. Study supervision: M.O. and T.I.
Funding sources: This work is supported by a Grant Aid for the Yakumo Foundation for Environmental Science and the Towa Foundation for Food Science & Research.
Data availability statement: All relevant data are within the manuscript.
Conflict of interest: The authors declare that there are no conflicts of interest.
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