Baker P W, Rye K A, Gamble J R, Vadas M A, Barter P J
University Department of Medicine, Royal Adelaide Hospital, Adelaide, Australia.
J Lipid Res. 2000 Aug;41(8):1261-7.
The ability of different phosphatidylcholine (PC) species to inhibit cytokine-induced expression of vascular cell adhesion molecule 1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) was investigated. PC species containing palmitoyl- in the sn-1 position and palmitoyl- (DPPC), arachidonyl- (PAPC), linoleoyl- (PLPC) or oleoyl- (POPC) in the sn-2 position were compared. These PC species were studied as components of reconstituted high density lipoproteins (rHDL) (containing apolipoprotein A-I [apoA-I] as the sole protein) or as small unilamellar vesicles (SUVs). The rHDL containing PLPC and PAPC inhibited VCAM-1 expression in activated HUVECs by 95 and 70%, respectively, at an apoA-I concentration of 16 micrometer. At this concentration of apoA-I, POPC rHDL inhibited by only 16% and DPPC rHDL did not inhibit at all. These differences could not be explained by differential binding of the rHDL to HUVECs. The same hierarchy of inhibitory activity was observed when these PC species were presented to the cells as SUVs but only when the SUVs also contained an antioxidant. It was concluded that rHDL PC is responsible for their inhibitory activity and that this varies widely with different PC species.
研究了不同磷脂酰胆碱（PC）种类在人脐静脉内皮细胞（HUVECs）中抑制细胞因子诱导的血管细胞黏附分子1（VCAM-1）表达的能力。比较了在sn-1位含有棕榈酰基且在sn-2位含有棕榈酰基（DPPC）、花生四烯酰基（PAPC）、亚油酰基（PLPC）或油酰基（POPC）的PC种类。这些PC种类作为重组高密度脂蛋白（rHDL）（仅含载脂蛋白A-I [apoA-I]作为唯一蛋白质）的成分或作为小单层囊泡（SUVs）进行研究。在apoA-I浓度为16微摩尔时，含有PLPC和PAPC的rHDL分别使活化的HUVECs中VCAM-1的表达抑制了95%和70%。在该apoA-I浓度下，POPC rHDL仅抑制了16%，而DPPC rHDL根本没有抑制作用。这些差异无法通过rHDL与HUVECs的差异结合来解释。当这些PC种类以SUVs形式呈现给细胞时，观察到了相同的抑制活性等级，但前提是SUVs也含有抗氧化剂。得出的结论是，rHDL中的PC负责其抑制活性，并且这种活性因不同的PC种类而有很大差异。
