title: Protein targets of oxidized phospholipids in endothelial cells.
abstract: Oxidation products of 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine (Ox-PAPC) are found in atherosclerotic lesions, apoptotic cells, and oxidized LDL and stimulate human aortic endothelial cells (HAECs) to produce inflammatory cytokines, leukocyte chemoattractants, and coagulation factors. This regulation is thought to be a receptor-mediated process in which oxidized phospholipids activate specific receptors on HAECs to evoke an inflammatory response. To characterize the HAEC proteins with which oxidized phospholipids interact, a biotinylated PAPC analog, 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidyl-(N-biotinylethanolamine) (PAPE-N-biotin), was synthesized. Oxidation of PAPE-N-biotin in air generated a mixture of biotin-labeled oxidized lipids analogous to Ox-PAPC. Ox-PAPE-N-biotin, like Ox-PAPC, induced interleukin-8 (IL-8) protein synthesis and stimulated IL-8, low density lipoprotein receptor, heme oxygenase-1, and activating transcription factor-3 mRNA expression in HAECs. After treatment of HAECs with Ox-PAPE-N-biotin, the cellular proteins were isolated and separated by SDS-PAGE. Western analysis with streptavidin-HRP demonstrated at least 20 different biotinylated HAEC proteins to which the Ox-PAPE-N-biotin was associated, which were not detected with unoxidized PAPE-N-biotin treatment. This work suggests that oxidized phospholipids, such as those found in oxidized LDL, apoptotic cells, and atherosclerotic lesions, form tight interactions with specific endothelial cell proteins, which may be responsible for the inflammatory response. Identification of these putative oxidized phospholipid targets may reveal therapeutic targets to modulate inflammation and atherosclerosis.
authors: Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
authors: B Gabriel
authors: BG
authors: Gugiu
authors: Kevin
authors: K
authors: Mouillesseaux
authors: Victoria
authors: V
authors: Duong
authors: Tabitha
authors: T
authors: Herzog
authors: Avetis
authors: A
authors: Hekimian
authors: Lukasz
authors: L
authors: Koroniak
authors: Thomas M
authors: TM
authors: Vondriska
authors: Andrew D
authors: AD
authors: Watson
mesh_terms: D050197:Atherosclerosis; D019921:Biotinylation; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000737:chemistry / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology; D006801:Humans; D007249:Inflammation / Q000209:etiology*; D015227:Lipid Peroxidation; D010713:Phosphatidylcholines / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism*; D011485:Protein Binding; D011506:Proteins / Q000032:analysis / Q000378:metabolism*
chemical_list: D010713:Phosphatidylcholines; D010743:Phospholipids; D011506:Proteins; C472349:oxidized-L-alpha-1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine