title: Polar lipids from the marine macroalga Palmaria palmata inhibit lipopolysaccharide-induced nitric oxide production in RAW264.7 macrophage cells.
abstract: The EtOAc soluble fraction of a MeOH/CHCl3 extract of Palmaria palmata showed strong nitric oxide (NO) inhibitory activity against lipopolysaccharide (LPS)-induced NO production in murine RAW264.7 cells. NO inhibition-guided isolation led to identification of three new polar lipids including a sulfoquinovosyl diacylglycerol (SQDG) (2S)-1-O-eicosapentaenoyl-2-O-myristoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)-glycerol (1) and two phosphatidylglycerols, 1-O-eicosapentaenoyl-2-O-trans-3-hexadecenoyl-3-phospho-(1'-glycerol)-glycerol (3) and 1-O-eicosapentaenoyl-2-O-palmitoyl-3-phospho-(1'-glycerol)-glycerol (4) from the EtOAc fraction. Seven known lipids were also isolated including a SQDG (2), a phospholipid (5) and five galactolipids (6-10). Structures of the isolated lipids were elucidated by spectral analyses. The isolated SQDGs, phosphatidylglycerols and phospholipid possessed strong and dose-dependent NO inhibitory activity compared to N(G)-methyl-L-arginine acetate salt (L-NMMA), a well-known NO inhibitor used as a positive control. Further study suggested that these polar lipids suppressed NO production through down-regulation of inducible nitric oxide synthase (iNOS).
authors.affiliation: Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada. Electronic address: arjun.banskota@nrc-cnrc.gc.ca.
authors.forename: Arjun H
authors.initials: AH
authors.lastname: Banskota
authors.affiliation: Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: Roumiana
authors.initials: R
authors.lastname: Stefanova
authors.affiliation: Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: Sandra
authors.initials: S
authors.lastname: Sperker
authors.affiliation: Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: Santosh P
authors.initials: SP
authors.lastname: Lall
authors.affiliation: Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, Canada.
authors.forename: James S
authors.initials: JS
authors.lastname: Craigie
authors.affiliation: Acadian Seaplants Limited, 30 Brown Avenue, Dartmouth, Nova Scotia B3B 1X8, Canada.
authors.forename: Jeff T
authors.initials: JT
authors.lastname: Hafting
authors.affiliation: Acadian Seaplants Limited, 30 Brown Avenue, Dartmouth, Nova Scotia B3B 1X8, Canada.
authors.forename: Alan T
authors.initials: AT
authors.lastname: Critchley
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques; D002460:Cell Line; D006017:Glycolipids / Q000302:isolation & purification / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D058086:Microalgae / Q000737:chemistry*; D015394:Molecular Structure; D009569:Nitric Oxide / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors; D010715:Phosphatidylglycerols / Q000302:isolation & purification / Q000494:pharmacology*; D000461:Rhodophyta / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D006017:Glycolipids; D008070:Lipopolysaccharides; D010715:Phosphatidylglycerols; C496611:sulfoquinovosylacylglycerol; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse
keywords: Anti-inflammatory activity; Dulse; Glycolipid; Lipids; Nitric oxide; Palmaria palmata; Palmariaceae; Phosphatidylglycerol; Phospholipid; Sulfolipid; iNOS