Ishige foliacea ameliorates depressive-like behaviors in stress hormone treated mice

Abstract

Chronic stress is an important factor to several physical and mental diseases. Ishige foliacea, an edible brown seaweed, has various biological properties; however, its role in alleviating stress-induced depression remains unclear. Thus, the antidepressant-like effects of I. foliacea ethanolic extract (IE) were investigated using corticosterone (CORT)-treated HT22 cells and CORT-induced depressive mice. IE significantly reduced the production of reactive oxygen species (ROS) and inhibited monoamine oxidase (MAO) activity and protein expression; furthermore, it up-regulated the extracellular signal-regulated kinase (ERK)-cAMP response element-binding protein (CREB)-brain derived neurotrophic factor (BDNF) signaling pathway. In the CORT-induced depressive mice, IE administration (500 mg/kg, bodyweight) exerted antidepressant effects according to behavioral tests. In addition, IE activated the ERK-CREB-BDNF signaling pathway owing to CORT exposure in the hippocampus. Therefore, IE inhibited ROS production and MAO activity and improved depressive behaviors caused by stress hormones, which demonstrates the therapeutic potential of IE in the treatment of depression.