A novel properties of rice bran: rice bran supplement alleviates chronic restraint stress-induced depression-like behaviors in mice

Abstract

Depression is emerging as a social and health-related issue in many countries. Rice bran supplement (RBS) possesses a variety of biological properties; however, its potential antidepressant effects have not been previously reported. This study investigated the antidepressant effects of RBS in a mouse model of chronic restraint stress (CRS)-induced depression. RBS (250, 500, and 1000 mg/kg) was administered to mice subjected to CRS for 5 weeks. RBS significantly improved depressive symptoms in CRS-exposed mice, as evidenced by increased sucrose preference and reduced immobility time. It reduced serum corticotropin-releasing hormone, adrenocorticotropic hormone, and corticosterone. Additionally, RBS downregulated the expression of glucocorticoid receptor and FK506 binding protein 5 and upregulated the ERK-CREB-BDNF pathway in the prefrontal cortex and hippocampus. Furthermore, RBS increased serotonin, dopamine, and norepinephrine levels and decreased monoamine oxidase mRNA and protein levels in the brain. Thus, RBS administration could be a promising therapeutic approach to treating chronic stress-induced depression.