Fermented rice milk ameliorates atopic dermatitis in mice via MAPK and NF-κB signaling pathway

Atopic dermatitis (AD), which is associated with inflammatory response and skin damage, is increasing worldwide in recent years. Interest is increasing in the protective effects of natural and fermented products on the prevention and treatment of AD. This study aimed to investigate the ameliorative effects of a new rice milk product fermented with Saccharomyces cerevisiae on AD mice. Fermented rice milk could effectively attenuated the symptoms of AD mice, such as skin lesions, scaliness and lichenification. Furthermore, fermented rice milk decreased the levels of inflammatory cytokines interleukin (IL)-4, IL-6 and tumor necrosis factor (TNF)-α in 2,4-dinitrochlorobenzene (DNCB) induced mice. It was also observed that fermented rice milk treatment downregulated the levels of p-IKBα, p-NF-κB, p-ERK, p-JNK and p-p38 proteins expression in skin of AD mice, which showed the anti-inflammatory function of fermented rice milk, mainly via the NF-κB and MAPK signaling pathways. In addition, S. cerevisiae fermentation reduced original flavor of rice milk, and increased the acid and alcohol compounds. Overall, the findings indicated that S. cerevisiae fermentation improved the flavor characteristics of rice milk, and fermented rice milk exhibited protective effects against DNCB-induced atopic dermatitis by downregulating NF-κB and MAPK signaling pathways and protecting the skin barrier.