Anti-inflammatory Effect of Petalonia binghamiae in LPSInduced Macrophages is Mediated by Suppression of iNOS and COX-2

A number of seaweed species are used as traditional medicine in different parts of the world. However, very few data on the anti-inflammatory effect of seaweed have been published. Petalonia binghamiae (Miyeoksoi), a brown alga, is a traditional food in the southern regions of the Korea peninsula. In this study, the anti-inflammatory effects of the ethyl acetate extracts of P. binghamiae were evaluated on lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. Our results supports that P. binghamiae potently inhibited LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production, exhibiting IC50 values of 38.8 and 9.3 ^g/mL. Consistent with these findings, P binghamiae reduced the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein level in a concentration-dependent manner, as determined by Western blotting. In addition, the levels of tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6) released into the medium were reduced by P binghamiae in a dose-dependent manner, exhibiting IC50 values of 19.4 ^g/mL for IL-6. Based on these results, the anti-inflammatory effects of P binghamiae extracts, together with their low cell toxicity, suggest potential therapeutic applications in the regulation of the inflammatory response. © 2010 Friends Science Publishers