Eicosanoids mediate a wide variety of physiological processes including inflammation. These lipid mediators are oxygenated metabolites of arachidonic acid and other poly- unsaturated fatty acids. Arachidonic acid levels in cells are tightly controlled by the release of this fatty acid from cell membranes by the action of one or more phospholipases A2. We are studying a family of phospholipases A2 called cytosolic phospholipases A2 (cPLA2s) including cPLA2?, which has been shown to catalyze arachidonic acid release from cellular membranes. We propose to continue our studies of the regulation of cPLA2? in mammalian cells by phosphorylation and by specific protein-membrane lipid interactions. The mammalian genome contains 6 cPLA2s isoforms. We will prepare recombinant forms of all of these proteins so that we can study the specificity of designed inhibitors toward the full set of cPLA2s. We will also use structure-guided design to prepare inhibitors that can distinguish between the 1 and 6 cPLA2 isoforms since these are the two cPLA2s that most likely play a role in arachidonic acid release. We will also study the role of cPLA2s and secreted phospholipases A2 (sPLA2s) in lipid mediator production from human platelets stimulated with a variety of agonists. Finally, we will further develop a new method for high sensitivity, multiplex analysis of eicosanoids that will be very useful in the inflammation field for studying eicosanoid levels in precious biological samples.
The relevance of our work is to discover the molecular basis for eicosanoid production in mammalian cells and tissues. Eicosanoids are lipid mediators that mediate inflammation including asthma and arthritis. The enzymes involved in generating free arachidonic acid, the precursor of the eicosanoids, are being identified, and their regulation is being studied.
|Yun, Bogeon; Lee, HeeJung; Ghosh, Moumita et al. (2014) Serine hydrolase inhibitors block necrotic cell death by preventing calcium overload of the mitochondria and permeability transition pore formation. J Biol Chem 289:1491-504|
|Bollinger, James G; Naika, Gajendra S; Rohan, Gajendra et al. (2013) LC/ESI-MS/MS detection of FAs by charge reversal derivatization with more than four orders of magnitude improvement in sensitivity. J Lipid Res 54:3523-30|
|Thompson, Wallace; Oslund, Rob C; Bollinger, James et al. (2012) High-throughput assay of secreted phospholipases A? inhibitors. Methods Mol Biol 861:149-58|
|Bryant, Katherine J; Bidgood, Matthew J; Lei, Pei-Wen et al. (2011) A bifunctional role for group IIA secreted phospholipase A2 in human rheumatoid fibroblast-like synoviocyte arachidonic acid metabolism. J Biol Chem 286:2492-503|
|Mouchlis, Varnavas D; Magrioti, Victoria; Barbayianni, Efrosini et al. (2011) Inhibition of secreted phospholipases A? by 2-oxoamides based on ?-amino acids: Synthesis, in vitro evaluation and molecular docking calculations. Bioorg Med Chem 19:735-43|
|Yang, Jia-Shu; Valente, Carmen; Polishchuk, Roman S et al. (2011) COPI acts in both vesicular and tubular transport. Nat Cell Biol 13:996-1003|
|Reed, Kathleen A; Tucker, Dawn E; Aloulou, Ahmed et al. (2011) Functional characterization of mutations in inherited human cPLA? deficiency. Biochemistry 50:1731-8|
|Bollinger, James G; Thompson, Wallace; Lai, Ying et al. (2010) Improved sensitivity mass spectrometric detection of eicosanoids by charge reversal derivatization. Anal Chem 82:6790-6|
|Lai, Ying; Oslund, Rob C; Bollinger, James G et al. (2010) Eosinophil cysteinyl leukotriene synthesis mediated by exogenous secreted phospholipase A2 group X. J Biol Chem 285:41491-500|
|Granata, Francescopaolo; Frattini, Annunziata; Loffredo, Stefania et al. (2010) Production of vascular endothelial growth factors from human lung macrophages induced by group IIA and group X secreted phospholipases A2. J Immunol 184:5232-41|
Showing the most recent 10 out of 57 publications