Suppression of stress by aroma: alterations in the expression of brain factors

ABSTRACT

Stress such as uncertainty about the future, including the problem of new coronavirus infection, is a very serious problem not only for physical health but also for mental health. It is certain that stress is one of the risk factors for developing mental disorders. We have found stress-responsive biomarker (stress marker) candidates through studies on the process from stress to disease onset. Recently, we have been trying to prove the stress-suppressing effect of aroma with brain factors. We analyzed how aroma affects behavioral changes due to stress and the expression of stress marker candidates in the brain. In this article, the data on aroma that we have accumulated so far will be introduced. Specifically, we will describe changes happened in experimental animals when they smelled coffee beans, lavender, cypress, a-pinene, and thyme linalool. When considering the biological effects of aroma, it is inevitable that not only the olfactory pathway but also odor molecules act through the bloodstream by nasal and transdermal absorption. The brain transferability of odor molecules may be a bottleneck in analyzing the biological effects of volatile components. Thus, we would like to discuss on this issue.