LDL are oxidatively modified by plateletsviaGP91phoxand accumulate in human monocytes
| Autor: | Francesco Violi, Luisa Lenti, Roberto Carnevale, Barbara Buchetti, Pasquale Pignatelli, S. Di Santo, Valerio Sanguigni |
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| Rok vydání: | 2006 |
| Předmět: |
Blood Platelets
medicine.medical_specialty Hypercholesterolemia gp91phox activation ros medicine.disease_cause Biochemistry Monocytes chemistry.chemical_compound Phospholipase A2 Internal medicine Genetics medicine Humans Vitamin E Platelet Platelet activation x-linked chronic granulomatous disease Molecular Biology Membrane Glycoproteins NADPH oxidase biology Chemistry Monocyte Lysophosphatidylcholines NADPH Oxidases Lipoproteins LDL Endocrinology Lysophosphatidylcholine medicine.anatomical_structure NADPH Oxidase 2 biology.protein Electrophoresis Polyacrylamide Gel lipids (amino acids peptides and proteins) Arachidonic acid Reactive Oxygen Species Oxidation-Reduction Oxidative stress Biotechnology |
| Zdroj: | The FASEB Journal. 21:927-934 |
| ISSN: | 1530-6860 0892-6638 |
| DOI: | 10.1096/fj.06-6908com |
| Popis: | Oxidative stress-mediated LDL modification has a key role in initiation of the atherosclerotic process. Platelets produce reactive oxidant species (ROS) upon stimulation with agonist, but it is uncertain whether they are able to oxidatively modify LDL. Human platelets taken from healthy subjects were incubated with LDL, then stimulated with collagen. Compared with unstimulated platelets, collagen-stimulated platelets induced LDL modification as shown by enhanced conjugated dienes and lysophosphatidylcholine formation, electrophoretic mobility, Apo B-100 degradation, and monocyte LDL uptake. Activated platelets also induced a marked reduction of vitamin E contained in LDL. A significant inhibition of LDL oxidation was observed in platelets treated with arachidonyl trifluomethyl ketone (AACOCF3), an inhibitor of phospholipase A2. The experiments reported above were also conducted in patients with hereditary deficiency of gp91phox, the central core of NADPH oxidase, and in patients with hypercholesterolemia. Platelets from gp91 phox-deficient patients produced a small amount of ROS and weakly modified LDL. Conversely, platelets from hypercholesterolemic patients showed enhanced ROS formation and oxidized LDL more than platelets from healthy subjects. This study provides evidence that platelets modify LDL via NADPH oxidase-mediated oxidative stress, a phenomenon that could be dependent on arachidonic acid activation. This finding suggests a role for platelets in favoring LDL accumulation within atherosclerotic plaque. |
| Databáze: | OpenAIRE |
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