Anti-Inflammatory Effects of Sargassum muticum Ethanol Extract in Lipopolysaccharide-Induced RAW 264.7 Cells and Mouse Ear Edema Models

This study investigated the effects and the anti-inflammatory activity of Sargassum muticum ethanol extract in lipopolysaccharide-induced RAW 264.7 murine macrophage cells and in a croton oil-induced mouse ear edema model. Pretreatment of lipopolysaccharide-induced RAW 264.7 cells with Sargassum muticum ethanol extract (0.1-100 mu g/ml) inhibited lipopolysaccharide-induced production of nitric oxide, interleukin-6 and tumour necrosis factor alpha in a dose-dependent manner. The expression of lipopolysaccharide-induced, inducible nitric oxide synthase and cyclooxygenase-2 in the Sargassum muticum ethanol extract-treated group was also suppressed in a dose-dependent manner. Furthermore, we found that Sargassum muticum ethanol extract induced anti-inflammatory effects by inhibiting Mitogen-activated protein kinases (extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38) and nuclear factor kappa B, p65 phosphorylation in lipopolysaccharide-stimulated RAW 264.7 cells. The anti-inflammatory activity of Sargassum muticum ethanol extract in vivo was evaluated in the ear edema model of a croton oil-treated mouse. Compared to the untreated control, croton oil-induced ear edema was found to be reduced by about 33 % upon treatment with 250 mg/kg Sargassum muticum ethanol extract.

Automated summary

This study found that Sargassum muticum ethanol extract has anti-inflammatory activity both in vitro and in vivo. It inhibits the production of nitric oxide, interleukin-6, and tumor necrosis factor alpha induced by lipopolysaccharide, and suppresses the expression of inducible nitric oxide synthase and cyclooxygenase-2. Furthermore, it induces anti-inflammatory effects by inhibiting the phosphorylation of several signaling pathways.