Nitro-oleic acid downregulates lipoprotein-associated phospholipase A2 expression via the p42/p44 MAPK and NFκB pathways

Sci Rep. 2014 May 9:4:4905. doi: 10.1038/srep04905.

Abstract

Nitro-oleic acid (OA-NO2), acting as anti-inflammatory signaling mediators, are involved in multiple signaling pathways. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is well known as a cardiovascular risk biomarker. Our results showed that OA-NO2 downregulated the expression of Lp-PLA2 in a time- and dose-dependent manner, whereas native OA had no such effect. Furthermore, OA-NO2 could repress Lp-PLA2 expression in the peripheral blood mononuclear cells of apo CIII-transgenic (apo CIII TG) pigs, which exhibited higher Lp-PLA2 expression and activity than did wild-type (WT) pigs. OA-NO2 inhibited Lp-PLA2 expression in macrophages, independent of nitric oxide formation and PPARγ-activation. However, OA-NO2 downregulates Lp-PLA2 by inhibiting the p42/p44 mitogen-activated protein kinase (MAPK) and the nuclear factor κB (NFκB) pathways. When used to mediate anti-inflammatory signaling, the regulation of inflammatory cytokines and SOD by OA-NO2 might be associated with the reduction of Lp-PLA2. These results suggested that OA-NO2 might exert a vascular-protective effect partially via Lp-PLA2 inhibition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-Alkyl-2-acetylglycerophosphocholine Esterase / genetics*
  • Animals
  • Cytokines / metabolism
  • Down-Regulation
  • Gene Expression Regulation / drug effects*
  • Humans
  • Inflammation Mediators / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism*
  • NF-kappa B / metabolism*
  • Nitric Oxide / metabolism
  • Oleic Acid / pharmacology*
  • PPAR gamma / metabolism
  • Signal Transduction / drug effects*
  • Superoxide Dismutase / metabolism
  • Swine

Substances

  • Cytokines
  • Inflammation Mediators
  • NF-kappa B
  • PPAR gamma
  • Oleic Acid
  • Nitric Oxide
  • Superoxide Dismutase
  • Mitogen-Activated Protein Kinase 3
  • 1-Alkyl-2-acetylglycerophosphocholine Esterase