title: Dietary (n-3) polyunsaturated fatty acids remodel mouse T-cell lipid rafts.
abstract: In vitro evidence indicates that (n-3) polyunsaturated fatty acids (PUFA) suppress T-cell activation in part by displacing proteins from lipid rafts, specialized regions within the plasma membrane that play an important role in T-cell signal transduction. However, the ability of (n-3) PUFA to influence membrane microdomains in vivo has not been examined to date. Therefore, we compared the effect of dietary (n-3) PUFA on raft (liquid ordered) vs. soluble (liquid disordered) microdomain phospholipid composition in mouse T cells. Mice were fed diets containing either 5 g/100 g corn oil (control) or 4 g/100 g fish oil [contains (n-3) PUFA] + 1 g/100 g corn oil for 14 d. Splenic T-cell lipid rafts were isolated by density gradient centrifugation. Raft sphingomyelin content (mol/100 mol) was decreased (P < 0.05) in T cells isolated from (n-3) PUFA-fed mice. Dietary (n-3) PUFA were selectively incorporated into T-cell raft and soluble membrane phospholipids. Phosphatidylserine and glycerophosphoethanolamine, which are highly localized to the inner cytoplasmic leaflet, were enriched to a greater extent with unsaturated fatty acids compared with sphingomyelin, phosphatidylinositol and glycerophosphocholine. These data indicate for the first time that dietary (n-3) PUFA differentially modulate T-cell raft and soluble membrane phospholipid and fatty acyl composition.
authors.affiliation: Faculty of Nutrition, Center for Environmental and Rural Health, Texas A&M University System, Health Science Center, College Station, TX, USA.
authors.forename: Yang-Yi
authors.initials: YY
authors.lastname: Fan
authors.forename: David N
authors.initials: DN
authors.lastname: McMurray
authors.forename: Lan H
authors.initials: LH
authors.lastname: Ly
authors.forename: Robert S
authors.initials: RS
authors.lastname: Chapkin
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D005260:Female; D050356:Lipid Metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D010743:Phospholipids / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism*; D014018:Tissue Distribution / Q000187:drug effects
chemical_list: D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D010743:Phospholipids