| Autor: |
Nicolaos Androulakis, Hervé Durand, Ewa Ninio, Demokritos C. Tsoukatos |
| Jazyk: |
angličtina |
| Rok vydání: |
2005 |
| Předmět: |
|
| Zdroj: |
Journal of Lipid Research, Vol 46, Iss 9, Pp 1923-1932 (2005) |
| Druh dokumentu: |
article |
| ISSN: |
0022-2275 |
| DOI: |
10.1194/jlr.M500074-JLR200 |
| Popis: |
Oxidation of LDL is thought to be involved in both initiating and sustaining atherogenesis through the formation of proinflammatory lipids and the covalent modification of LDL particles. Platelet-activating factor (PAF; 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is a potent phospholipid mediator involved in inflammation. Upon oxidation of LDL, oxidized phospholipids with PAF-like structure are generated, and some of them may act via the PAF receptor. We evaluated the contribution of 1-0-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (C16:0 PAF) and of other PAF analogs on the PAF-like bioactivity formed upon Cu2+-initiated oxidation of LDL. Reverse-phase HPLC purification and electrospray ionization-MS analyses showed that upon oxidation of LDL with inactivated PAF-acetylhydrolase (PAF-AH), C16:0 PAF accounted for >30% of PAF-like biological activity and its sn-2 butenoyl analog accounted for >50%. However, upon LDL oxidation in the presence of exogenous 1-0-alkyl-sn-glycero-3-phosphocholine (lyso-PAF) without PAF-AH inactivation, C16:0 PAF formation accounted for >90% of the biological activity recovered. We suggest that the C16:0 PAF, despite being a minor constituent of the LDL peroxidation products, may contribute substantially to the bioactivity formed in oxidized LDL.The higher bioactivity of C16:0 PAF, and the higher selectivity of the LDL-attached lyso-PAF transacetylase toward very short acyl chains [acetate (C2) vs. butanate (C4)], may explain the contribution described above. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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