メンタルヘルスを支える栄養科学 : 食品成分の抗うつ様活性評価

Nowadays anti-stress effect of food ingredients attracts much attention from the standpoint of maintenance of mental health. Nevertheless, definitive evidence on the effect is very few in human studies. The University of Tokushima proceeded the２１st -Century COE Program,“Human Nutrition Science on Stress Control”, from ２００４ to ２００８. In this program, we carried out the screening and evaluation of antidepressant-like effect of plant polyphenols. It is suggested that plant polyphenols are able to suppress brain mitochondrial monoamine oixidase-A（MAO-A）activity which is responsible for the serotonin metabolism in synapses. In addition, intake of quercetin, a representative plant polyphenol, seems to affect hypothalamus-pituitary gland-adrenal cortex axis（HPA axis）leading to the suppression of plasma cortisol. It is therefore likely that plant polyphenols act as anti-stress ingredients from foods to contribute metal health, although more studies including human trials are obviously required.