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.

Effects of serum of the rats ventilated with high tidal volume on endothelial cell permeability and therapeutic effects of ulinastatin

Background With the widespread use of ventilators in treating critically ill patients, the morbidity of ventilator-induced lung injury （VILI） is increasing accordingly. VILI is characterized by a considerable increase in microvascular leakiness and activation of inflammatory processes. In this study we investigated the effects of inflammatory mediators in VILI rat serum on endothelial cytoskeleton and monolayer cellular permeability, as well as the therapeutic effect of ulinastatin, to explore the pathogenesis and the relationship between biotrauma and lung oedema induced by VILI. Methods Thirty healthy male Sprague-Dawley rats were randomly divided into three groups： group A （normal tidal volume ventilation）, group B （high tidal volume ventilation） and group C （high tidal volume ventilation plus ulinastatin）. The serum of each rat after ventilation was added to endothelial cell line ECV-304 medium for two hours to observe the effects of serum and/or ulinastatin on endothelial fibrous actin and permeability. Results Compared to rats ventilated with normal tidal volume, serum of rats ventilated with high tidal volume caused a striking reorganization of actin cytoskeleton with a weakening of fluorescent intensity at the peripheral filament bands and formation of the long and thick stress fibres in the centre resulting in endothelial contraction and higher permeability. Prior treatment with ulinastatin lessened the above changes significantly. The changes of permeability coefficient of endothelial permeability after group A, B or C rats serum stimulation were （6.95 ± 1.66）%, （27.50±7.77）% and （17.71±4.66）% respectively with statistically significant differences （P〈0.05） among the three groups. Conclusions The proinflammatory mediators in the serum of the rats given high tidal volume ventilation increases endothelial permeability by reorganizing actin cytoskeleton, and pretreatment with ulinastatin lessens the permeability by inhibiting of proinflammatory mediators.