Fucoxanthin inhibits the inflammatory response by suppressing NF-κB and MAPKs activation in LPS-induced RAW 264.7 macrophages

Abstract

In the present study, we investigated the anti-inflammatory effects of fucoxanthin, a natural biologically active substance isolated from Ishige okamurae by examining its inhibitory effects on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells. Fucoxanthin caused dose-dependent reductions in the levels of inducible nitric oxide (iNOS) at protein and mRNA levels and concomitant decreases in NO production. In addition, it was found that fucoxanthin suppressed the production and mRNA expressions of inflammatory cytokines, such as, IL-1β, TNF-α and IL-6. Furthermore, fucoxanthin inhibited the cytoplasmic degradation of IκB-α, and the nuclear translocation of p50 and p65 protein, leading to less NF-κB transactivation. In addition, fucoxanthin dose-dependently inhibited the phosphorylations of JNK, ERK and p38. Taken together, these results suggest that fucoxanthin reduces levels of the pro-inflammatory mediators, such as, NO, iNOS, IL-1β, TNF-α, and IL-6 through the inhibition of NF-κB activation and suppression of JNK, ERK and p38 phosphorylation in RAW 264.7 cells. These findings reveal in part the molecular basis for the anti-inflammatory properties of fucoxanthin.