Jeju seaweeds suppress lipopolysaccharide-stimulated proinflammatory response in RAW 264.7 murine macrophages

Objective:To investigate the anti-inflammatory effects of Jeju seaweeds on macrophage RAW264.7 cells under lipopolysaccharide(LPS)stimulation.Methods:Ethyl acetate fractions were prepared from five different types of Jeju seaweeds,Dictyopteris divaricata(D.divaricata),Dictyopteris prolifera(D.prolifefa),Prioutis cornea(P.comea,Grateloupia laceolata(G,lanceolate,and Cralcloupia filicina(G.filicina)They were screened for inhibitory effects on proinflammatory mediators and cytokines such as nitric oxide(NO),prostaglandin E,,tumor necrosis factor-a(TNF-a),and interleukin-6(11.-6).Results:Our results revealed that D.divaricata,D.prolifera,P.cornea,G.lanceolata,and G.filicina potently inhibited I.PS-stimulaled NO production(IC_(50),values were 18.0,38.36,38.43,32.81 and 37.14μg/mL,respectively).Consistent with these findings,D.divtricata,D.prolifera,P.cornea,and G.fdicina also reduced the IPS-induced and prostaglandin E,production in a concentration-dependent manner.Expectedly,they suppressed the expression of inducible NO synthase and cyclooxygenase-2 at the protein level in a dose-dependent manner in the RAW264.7 cells,as detennined by western blotting.In addition,the levels of TNF-a and IL-6,released into the medium,were also reduced by D.divaricata,D.prolifera,P.cornea,G,lanceolata,and G.fdicina in a dose-dependent manner(IC_(50)values for TNF-a were 16.11,28.21,84.27,45.52 and74.75μg/mL,respectively;IC_(50),values for IL-6 were 37.35,80.08,103.28,62.53 and 84.28μg/mL,respectively).The total phlorotannin content was measured by the Folin-Ciocalteu method and expressed as phloroglucinol equivalents.The content was 92.0μg/mg for D.divaricata,151.8μg/mg for D.prolifera,57.2μg/mg for P.cornea,53.0 pg/mg for G.lanceolata,and 40.2μg/mg for G.fdicina.Conclusions:Thus,these findings suggest that Jeju seaweed extracts have potential therapeutic applications for inflammatory responses.

Inhibitory effect of Jeju endemic seaweeds on the production of pro-inflammatory mediators in mouse macrophage cell line RAW 264.7

Seaweed has been used in traditional cosmetics and as a herbal medicine in treatments for cough,boils,goiters,stomach ailments,and urinary diseases,and for reducing the incidence of tumors,ulcers,and headaches.Despite the fact that seaweeds are frequently used in the practice of human health,little is known about the role of seaweed in the context of inflammation.This study aimed to investigate the influence of Jeju endemic seaweed on a mouse macrophage cell line(RAW 264.7) under the stimulation of lipopolysaccharide(LPS).Ethyl acetate extracts obtained from 14 different kinds of Jeju seaweeds were screened for inhibitory effects on pro-inflammatory mediators.Our results revealed that extracts from five seaweeds,Laurencia okamurae,Grateloupia elliptica,Sargassum thun-bergii,Gloiopeltis furcata,and Hizikia fusiformis,were potent inhibitors of the production of pro-inflammatory mediators such as nitric oxide(NO),prostaglandin E2(PGE2),interleukin-6(IL-6),and tumor necrosis factor-α(TNF-α).Based on these results,the anti-inflammatory effects and low cell toxicity of these seaweed extracts suggest potential thera-peutic applications in the regulation of the inflammatory response.