Fucofuroeckol-A fromEisenia bicyclisInhibits Inflammation in Lipopolysaccharide-Induced Mouse Macrophages via Downregulation of the MAPK/NF-κB Signaling Pathway

Abstract

Fucofuroeckol-A (FF) isolated from an edible perennial brown seaweedEisenia bicycliswas shown to be potent anti-inflammatory agents. FF suppressed the production of nitric oxide (NO) and prostaglandin E2(PGE2) and the expression of inducible nitric oxide synthase and cyclooxygenase-2 dose dependently in lipopolysaccharide- (LPS-) induced RAW 264.7 mouse macrophages. An enzyme-linked immunosorbent assay and cytometric bead array assay demonstrated that FF significantly reduced the production of proinflammatory cytokines, such as interleukin-6 and tumor necrosis factor-α, and that of the monocyte chemoattractant protein-1. Moreover, FF reduced the activation of nuclear factorκB (NF-κB) and mitogen-activated protein kinases (MAPKs). These results strongly suggest that the inhibitory effects of fucofuroeckol-A fromE. bicyclison LPS-induced NO and PGE2production might be due to the suppression of the NF-κB and MAPK signaling pathway.

Orally Administered Phlorotannins from Eisenia arborea Suppress Chemical Mediator Release and Cyclooxygenase-2 Signaling to Alleviate Mouse Ear Swelling

“…In particular, only 6,8′-bieckol at 10 μM was able to suppress COX-2 mRNA expression ( Figure 2 ). Although the suppression effects of purified phlorotannins on COX-2 mRNA expression in the mouse macrophage cell line RAW 264.7 were already demonstrated in a previous study [ 8 , 26 , 36 ], this is the first report in mast cell line RBL-2H3. The six phlorotannins at 500 μM inhibited COX-2 enzymatic activity ( Figure 3 ).…”

“…The RBL cells were stimulated by antigen-antibody reaction or A23187. According to previously reported phlorotannin concentration ranging 1 to 200 μM in cultured model cell experiments [ 7 , 8 , 10 , 26 , 27 , 28 , 29 ], we chose a concentration range from 10 to 200 μM in our experiments.…”

“…The six phlorotannins at 500 μM inhibited COX-2 enzymatic activity ( Figure 3 ). There are reports that purified phlorotannins reduce COX-2 signaling via suppression of MAPK/NF-κB signaling [ 8 , 26 , 27 ]. Accordingly, the suppression effects of the six purified phlorotannins tested here could be attributed to COX-2 mRNA expression via suppression of MAPK/NF-κB signaling and inhibition of COX-2 activity in mast cells accumulated in inflamed tissues.…”

“…There are, therefore, several reports of their anti-allergenic and anti-inflammatory effects. In recent reports, phlorotannin extracts from Fucales inhibited lipoxygenase activity and nitrite oxide production from RAW 264.7 cells, and some phlorotannins from Ecklonia cava , Ecklonia stolonifera and Eisenia bicyclis suppressed inflammation through the MAPK cascade or through chemical mediator production in BV-2, HaCaT and RAW 264.7 cells [ 6 , 7 , 8 , 9 , 10 ]. In our previous study, we isolated six phlorotannins (eckol; 6,6′-bieckol; 6,8′-bieckol; 8,8′-bieckol; PFF-A and PFF-B, Figure 1 ) from the brown alga Eisenia arborea [ 11 , 12 ], and reported the anti-allergenic and anti-inflammatory effects of their phlorotannins [ 13 , 14 ].…”

Marine natural products

“…330 The rst total synthesis of dictyoxetane 331,332 and the unnatural enantiomer (À)-erogorgiaene, 333 were reported. Additionally, there were many papers dealing with the biological properties of brown algal lipids, [334][335][336][337] polyphenolics [338][339][340][341][342][343][344][345][346][347][348] and carotenoids. [349][350][351][352][353][354][355][356][357][358][359][360] 6 Red algae…”