Linoleic acid-induced endothelial activation: Role of calcium and peroxynitrite signaling

Viswanathan Saraswathi, Guoyao Wu, Michal Toborek, Bernhard Hennig

Research output: Contribution to journalArticle

43 Scopus citations

Abstract

Hypertriglyceridemia, an important risk factor of atherosclerosis, is associated with increased circulating free fatty acids. Research to date indicates that linoleic acid (LA), the major fatty acid in the American diet, may be atherogenic by activating vascular endothelial cells. However, the exact signaling mechanisms involved in LA-mediated proinflammatory events in endothelial cells still remain unclear. We previously reported increased superoxide formation after LA exposure in endothelial cells. The objective of the present investigation is to determine the role of calcium and peroxynitrite in mediating the proinflammatory effect of LA in vascular endothelial cells. LA exposure increased intracellular calcium, nitric oxide, and tetrahydrodiopterin levels as well as the expression of E-selectin. Inhibiting calcium signaling using 1,2-bis(2-aminophenoxy)-ethane-N,N,N′,N′-tetraacetic acid and heparin decreased the expression of E-selectin. Also, LA-mediated nuclear factor kappa B activation and E-selectin gene expression were suppressed by Mn (III) tetrakis (1-methyl-4-pyridyl) porphyrin pentachloride (a superoxide scavenger), NG-monomethyl-L-arginine (an endothelial nitric oxide synthase inhibitor), and 5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron (III) chloride (a peroxynitrite scavenger). LA exposure resulted in increased nitrotyrosine levels, as observed by Western blotting and immunofluorescence. Our data suggest that the proinflammatory effects of LA can be mediated through calcium and peroxynitrite signaling.

Original languageEnglish (US)
Pages (from-to)794-804
Number of pages11
JournalJournal of Lipid Research
Volume45
Issue number5
DOIs
StatePublished - May 1 2004

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Keywords

  • Adhesion molecules
  • Endothelial nitric oxide synthase
  • Fatty acid
  • Nitric oxide
  • Nitrotyrosine
  • Nuclear factor kappa B
  • Oxidative stress
  • Tetrahydrobiopterin

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology
  • Cell Biology

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