Engelmann B, Bräutigam C, Thiery J
Physiologisches Institut der Universität München, Germany.
Biochem Biophys Res Commun. 1994 Nov 15;204(3):1235-42. doi: 10.1006/bbrc.1994.2595.
A phospholipid subgroup with potential antioxidant properties, the plasmalogen (1-alkenyl, 2-acyl-) fraction, was determined to constitute about 4.5% of total LDL phospholipids. In vitro oxidation of LDL by 2,2'-azobis-(2-amidinopropane hydrochloride) (AAPH, 0.5-10mM) or 5 microM copper induced a selective reduction of plasmalogen subgroups in phosphatidylcholine and phosphatidylethanolamine by 15%-35% within 30 min. Under the same experimental conditions alpha tocopherol (vitamin E) levels were lowered by 5%-40%, indicating a comparable sensitivity of plasmalogen phospholipids and alpha tocopherol towards oxidative attack by AAPH and copper. In vitro enrichment of LDL with 1-alkenyl, 2-lyso-phosphatidylcholine increased the lag phase of formation of conjugated double bonds induced by oxidation of the particles with copper. Incorporation of the lyso plasmalogen did not affect the maximal contents of conjugated dienes in copper oxidized LDL. Due to their relatively high concentration in LDL, their pronounced sensitivity towards oxidation and their capacity to increase the oxidative resistance of the particles, plasmalogen phospholipids may play a significant role in the defense of LDL particles against oxidative stress.
一种具有潜在抗氧化特性的磷脂亚组，即缩醛磷脂（1-烯基，2-酰基-）部分，被测定占总低密度脂蛋白（LDL）磷脂的约4.5%。用2,2'-偶氮二（2-脒基丙烷盐酸盐）（AAPH，0.5 - 10mM）或5 microM铜对LDL进行体外氧化，在30分钟内导致磷脂酰胆碱和磷脂酰乙醇胺中的缩醛磷脂亚组选择性降低15% - 35%。在相同实验条件下，α-生育酚（维生素E）水平降低了5% - 40%，表明缩醛磷脂和α-生育酚对AAPH和铜的氧化攻击具有相当的敏感性。用1-烯基，2-溶血磷脂酰胆碱对LDL进行体外富集，增加了用铜氧化颗粒诱导的共轭双键形成的延迟期。溶血缩醛磷脂的掺入不影响铜氧化LDL中共轭二烯的最大含量。由于它们在LDL中的相对高浓度、对氧化的明显敏感性以及增加颗粒抗氧化性的能力，缩醛磷脂可能在保护LDL颗粒免受氧化应激方面发挥重要作用。
