Characterization of phospholipids in pre-alpha HDL: selective phospholipid efflux with apolipoprotein A-I.
Characterization of phospholipids in pre-alpha HDL: selective phospholipid efflux with apolipoprotein A-I.
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发表时间：
1998-08
影响因子：
6.5
通讯作者：
Wenwu Zhang;B. Asztalos;Paul S. Roheim;L. Wong
中科院分区：
文献类型：
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作者：
Wenwu Zhang;B. Asztalos;Paul S. Roheim;L. Wong
以前，我们已经表明，无脂质的apoA-I，当与成纤维细胞孵育时，将产生前α迁移率的脂蛋白（Asztalos，B. F.、等，1997年。Arterioscler. Thromb. Vasc. 17：1630-1636）。为了了解这些前α粒子的性质，我们进一步表征了它们的脂质含量。前α颗粒是高密度脂蛋白，具有1.08 g/ml的中值密度。它们的表面电荷为-18.45 mV。这些颗粒的磷脂组成表明，它们具有4%的磷脂酰乙醇胺和肌醇; 69%的磷脂酰胆碱和18%的鞘磷脂。该磷脂组成不同于血浆HDL（81%磷脂酰胆碱，13%鞘磷脂）、成纤维细胞上的质膜和整个成纤维细胞磷脂。为了证明前-α流动性存在于脂质中，将来自前-α脂蛋白的脂质用无脂质apoA-I重构。所得粒子保留其前α流动性。我们的结论是，载脂蛋白A-I可能与质膜的特定区域反应，以获得这种不寻常的脂质组合物和前α流动性是由不寻常的磷脂组合物的一部分。
Previously, we have shown that lipid-free apoA-I, when incubated with fibroblasts, will produce lipoproteins of pre-alpha mobility (Asztalos, B. F., et al. 1997. Arterioscler. Thromb. Vasc. Biol. 17: 1630-1636). In order to understand the nature of these pre-alpha particles, we further characterized their lipid content. The pre-alpha particles are high density lipoproteins, having a median density of 1.08 g/ml. They have a surface charge of -18.45 mV. The phospholipid composition of these particles showed that they have 4% each of phosphatidyl ethanolamine and inositol; 69% phosphatidyl choline and 18% sphingomyelin. This phospholipid composition is different from those of plasma HDL (81% phosphatidyl choline, 13% sphingomyelin), plasma membrane on the fibroblasts, and whole fibroblast phospholipid. To demonstrate that the pre-alpha mobility resides in the lipids, lipids from pre-alpha lipoproteins were reconstituted with lipid-free apoA-I. The resultant particles retained their pre-alpha mobility. We conclude that apoA-I may react with specific regions of plasma membrane to acquire this unusual lipid composition and that pre-alpha mobility is caused in part by the unusual phospholipid composition.