title: Anti-inflammatory activity of edible brown alga Eisenia bicyclis and its constituents fucosterol and phlorotannins in LPS-stimulated RAW264.7 macrophages.
abstract: Although individual phlorotannins contained in the edible brown algae have been reported to possess strong anti-inflammatory activity, the responsible components of Eisenia bicyclis have yet to be fully studied. Thus, we evaluated their anti-inflammatory activity via inhibition against production of lipopolysaccharide (LPS)-induced nitric oxide (NO) and tert-butylhydroperoxide (t-BHP)-induced reactive oxygen species (ROS), along with suppression against expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), in RAW 264.7 cells. The anti-inflammatory activity potential of the methanolic extract and its fractions of E. bicyclis was in the order of dichloromethane>methanol>ethyl acetate>n-butanol. The strong anti-inflammatory dichloromethane fraction was further purified to yield fucosterol. From the ethyl acetate fraction, six known phlorotannins were isolated: phloroglucinol, eckol, dieckol, 7-phloroeckol, phlorofucofuroeckol A and dioxinodehydroeckol. We found that these compounds, at non-toxic concentrations, dose-dependently inhibited LPS-induced NO production. Fucosterol also inhibited t-BHP-induced ROS generation and suppressed the expression of iNOS and COX-2. These results indicate that E. bicyclis and its constituents exhibited anti-inflammatory activity which might attribute to inhibition of NO and ROS generation and suppression of the NF-κB pathway and can therefore be considered as a useful therapeutic and preventive approach to various inflammatory and oxidative stress-related diseases.
authors.affiliation: Department of Food Science and Human Nutrition, Chonbuk National University, Jeonju 561-756, Republic of Korea.
authors.forename: Hyun Ah
authors.initials: HA
authors.lastname: Jung
authors.forename: Seong Eun
authors.initials: SE
authors.lastname: Jin
authors.forename: Bo Ra
authors.initials: BR
authors.lastname: Ahn
authors.forename: Chan Mi
authors.initials: CM
authors.lastname: Lee
authors.forename: Jae Sue
authors.initials: JS
authors.lastname: Choi
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D002461:Cell Line, Transformed; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000737:chemistry / Q000378:metabolism; D004146:Dioxanes / Q000009:adverse effects / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D055951:Functional Food / Q000032:analysis*; D044423:Kelp / Q000737:chemistry*; D008264:Macrophages / Q000187:drug effects* / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D051379:Mice; D009569:Nitric Oxide / Q000037:antagonists & inhibitors / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism; D009994:Osmolar Concentration; D018384:Oxidative Stress / Q000187:drug effects; D010696:Phloroglucinol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000009:adverse effects / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism; D056910:Republic of Korea; D012997:Solvents / Q000737:chemistry; D013265:Stigmasterol / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000893:Anti-Inflammatory Agents; D004146:Dioxanes; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012997:Solvents; D009569:Nitric Oxide; C015896:fucosterol; D013265:Stigmasterol; D010696:Phloroglucinol; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2
keywords: 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine hydrochloride; 2′,7′-dichlorodihydrofluorescein; 2′,7′-dichlorodihydrofluorescein diacetate; 2′,7′-dichlorofluorescein; 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide; 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; AMT; Anti-inflammation; COX-2; DCF; DCFH; DCFH-DA; DMEM; DMSO-d(6); Dulbecco’s Modified Eagle’s Medium; Eisenia bicyclis; FBS; Fucosterol; HRP; LPS; MTT; NO; NOS; PVDF; Phlorotannin; ROS; TLC; Trolox; cyclooxygenase-2; deuterated dimethylsulfoxide; fetal bovine serum; horseradish peroxidase; iNOS; inducible nitric oxide synthase; lipopolysaccharide; nitric oxide; nitric oxide synthase; polyvinylidene fluoride; reactive oxygen species; t-BHP; tert-butylhydroperoxide; thin layer chromatography