title: Dichloromethane fraction of Laminaria japonica ethanolic extract inhibits lipopolysaccharide-induced nitric oxide synthase and cyclooxygenase-2 expression in RAW 264.7 cells via NF-κB pathway.
abstract: Strong anti-inflammatory activity has been found in Laminaria japonica dichloromethane fraction (LDF); however, the molecular mechanisms underlying its anti-inflammatory activity are not reported. Our results indicated that LDF inhibited LPS-induced nitric oxide and prostaglandin E(2) production in a dose-dependent manner and suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in RAW 264.7 cells. Also, levels of pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin (IL)-1β and IL-6 were remarkably reduced by LDF in LPS-treated RAW 264.7 cells. LDF greatly inhibited promoter activity of nuclear factor-κB (NF-κB) and translocation of NF-κB subunits by prevention of the degradation of inhibitor κB-α in LPS-treated RAW 264.7 cells (p < 0.05). Moreover, LDF inhibited activation of mitogen-activated protein kinases and AKT in LPS-treated RAW 264.7 cells. These results indicate that the LDF downregulates iNOS and COX-2 expressions through the suppression of NF-κB pathway associated with inhibition of multiple signaling proteins.
authors.affiliation: Department of Food Science and Nutrition, Pukyong National University, 599-1, Daeyeon-dong, Nam-gu, Busan 608-737, South Korea.
authors.forename: Ji-Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Min-Sup
authors.initials: MS
authors.lastname: Lee
authors.forename: Ji-Woong
authors.initials: JW
authors.lastname: Choi
authors.forename: Tai Sun
authors.initials: TS
authors.lastname: Shin
authors.forename: Hee-Chul
authors.initials: HC
authors.lastname: Woo
authors.forename: Hyeung-Rak
authors.initials: HR
authors.lastname: Kim
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000378:metabolism*; D015232:Dinoprostone / Q000096:biosynthesis / Q000378:metabolism; D015536:Down-Regulation; D020672:I-kappa B Proteins / Q000235:genetics; D007249:Inflammation; D053583:Interleukin-1beta / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis / Q000378:metabolism; D007795:Laminaria; D008070:Lipopolysaccharides; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000096:biosynthesis / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics; D010936:Plant Extracts / Q000494:pharmacology*; D011401:Promoter Regions, Genetic / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000096:biosynthesis / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D020672:I-kappa B Proteins; D053583:Interleukin-1beta; D015850:Interleukin-6; D008070:Lipopolysaccharides; D016328:NF-kappa B; D010936:Plant Extracts; D014409:Tumor Necrosis Factor-alpha; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D015232:Dinoprostone