Sufficient intake of high-fat food attenuates stress-induced social avoidance behavior

Aims: Psychosocial stress is a form of mental stress associated with human relationships that underlies the pathogenesis of mental disorders such as depression. Previous studies have suggested that intake of energy-dense foods, also known as “palatable foods,” can relieve psychosocial stress. However, it remains unclear whether the volume of palatable food affects abnormal behavior induced by psychosocial stress. In the present study, we aimed to determine whether levels of high-fat food intake significantly influence psychosocial stress using the social-defeat stress (SDS) paradigm.
Main methods: Mice subjected to SDS ate either a high-fat or normal chow diet for 10 days. Behavioral tests were conducted following the completion of the SDS paradigm. The hypothalamus, liver, and blood were examined post-mortem.
Key findings: Mice with sufficient intake of high-fat chow immediately following exposure to SDS did not exhibit social avoidance behavior, suggesting that a high-fat diet may improve social behavior. However, inadequate intake of high-fat food, which did not alter cholesterol metabolism or hypothalamic-pituitary-adrenal axis activity, was not associated with such benefits, instead increased anxiety-like behavior.
Significance: The results of the present study demonstrate that eating a high-fat diet may attenuate stress, but that this benefit disappears with insufficient intake of high-fat foods. The benefits of a high-fat diet under SDS may be related to cholesterol metabolism in the liver.

内容要旨・審査要旨・論文本文の公開
本論文は，著者Airi Otsukaの学位論文として提出され，学位審査・授与の対象となっている。

© 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/