Dynamics of arachidonic acid mobilization by inflammatory cells

Abstract

The development of mass spectrometry-based techniques is opening new insights into the understanding of arachidonic acid (AA) metabolism. AA incorporation, remodeling and release are collectively controlled by acyltransferases, phospholipases and transacylases that exquisitely regulate the distribution of AA between the different glycerophospholipid species and its mobilization during cellular stimulation. Traditionally, studies involving phospholipid AA metabolism were conducted by using radioactive precursors and scintillation counting from thin layer chromatography separations that provided only information about lipid classes. Today, the input of lipidomic approaches offers the possibility of characterizing and quantifying specific molecular species with great accuracy and within a biological context associated to protein and/or gene expression in a temporal frame. This review summarizes recent results applying mass spectrometry-based lipidomic approaches to the identification of AA-containing glycerophospholipids, phospholipid AA remodeling and synthesis of oxygenated metabolites.

Antibody-Opsonized Bacteria Evoke an Inflammatory Dendritic Cell Phenotype and Polyfunctional Th Cells by Cross-Talk between TLRs and FcRs

“…Additionally, we used a novel quantitative mass spectrometry lipidomics approach (22) to profile 120 inflammatory eicosanoids (17)(18)(19)26). iDCs stimulated with IgG-opsonized E. coli demonstrated clear synergistic differences in the secretion of cyclooxygenase (COX)-dependent and lipoxygenase (LOX)-dependent metabolites compared with iDCs stimulated with E. coli (Table I).…”

A quantitiative LC-MS/MS method for the measurement of arachidonic acid, prostanoids, endocannabinoids, N-acylethanolamines and steroids in human plasma

“…They are produced upon the enzymatic oxygenation of AA by cyclooxygenase-2 (COX-2) resulting in e.g. the production of prostaglandin E 2 (PGE 2 ) and thromboxane B 2 (THB B 2 ) [5]. Attention has recently been paid to the fact that like AA, ECs containing an arachidonoyl moiety are good substrates of COX-2, leading to the formation of similar prostanoid derivatives (e.g., prostaglandin E 2 ethanolamide (PGE 2 EA)) [6].…”

Group V Secreted Phospholipase A2 Is Upregulated by IL-4 in Human Macrophages and Mediates Phagocytosis via Hydrolysis of Ethanolamine Phospholipids

“…This reaction is especially important when the fatty acid liberated is arachidonic acid (AA), which can be converted into biologically active compounds called eicosanoids (2,3). Free fatty acids also may act as intracellular signalers on their own (4), and lysophospholipids may initiate signaling through cell surface G protein-coupled receptors (5).…”