Atopic dermatitis (AD) is a chronic inflammation associated with skin hypersensitivity caused by environmental factors. The objent of this study was to assess the hot water extracts of Sargassum horneri (SHHWE) on AD. AD was induced by spreading 2,4-dinitrochlorobenzene (DNCB) on the BALB/c mice. The efficacy of SHHWE was tested by observing the immunoglobulin E (IgE), cytokine, skin clinical severity score and cytokine secretions in concanavalin A (Con A)-stimulated splenocytes. The levels of interleukine (IL)-4, IL-5 and IgE, the pro-inflammatory cytokines that are closely related, were notably suppressed in a does-dependent manner by SHHWE, whereas the level of interferon γ (IFN-γ), the atopy-related Th1 cytokine inhibiting the production of Th2 cytokines, was increased. Therefore, these results show that SHHWE has a potent anti-inhibitory effect on AD and is highly valuable for cosmetic development.

In this study, the anti-inflammatory effects of Monostroma crassidermum Tokida ethanol extract (MCEE) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and croton oil-stimulated ICR mouse models were investigated. MCEE reduced the secretion of pro-inflammatory cytokines, including interleukin-6, IL-1β, tumor necrosis factor-α, and nitric oxide, which are non-toxic to RAW 264.7 cells. In vivo testing showed that the results in the MCEE-treated group (10-250 mg/kg. body weight) were similar to those in the prednisolone-treated group (10 mg/kg. body weight). Photomicrographs showed that the skin layer was thinned, and mast cell infiltration was reduced in the mouse-ear tissue. Therefore, these results suggested that MCEE exerts an anti-inflammatory effect, indicating the possible applications of MCEE as a natural anti-inflammatory material.