Tertov V V, Sobenin I A, Gabbasov Z A, Popov E G, Orekhov A N
Institute of Experimental Cardiology, USSR Cardiology Research Center, Moscow, Russia.
Biochem Biophys Res Commun. 1989 Aug 30;163(1):489-94. doi: 10.1016/0006-291x(89)92163-3.
We have tested a hypothesis that aggregates of modified low density lipoproteins (LDL) play the key role in the accumulation of lipids by cells of unaffected aortic intima. It was demonstrated using analysis of relative dispersion of light transmission fluctuations as well as gel filtration on Sepharose CL-2B that LDL modified by oxidation, glycosylation, desialylation and malondialdehyde treatment form aggregates under the conditions of culture. Native LDL failed to aggregate under the same conditions. It was demonstrated that modified LDL, unlike native LDL, bring about a 2- to 3-fold rise in cholesteryl ester levels of cultured cells. Moreover, direct and strong correlation (r = 0.86) was observed between the degree of lipoprotein aggregation and the amount of cholesteryl esters accumulated. Removal of modified LDL aggregates by filtration through a 0.1 micron filter or gel filtration completely prevented the intracellular accumulation of cholesteryl esters. These findings indicate that LDL aggregates play an essential, if not the decisive, role in the intracellular accumulation of lipids in vitro.
我们检验了一个假说，即修饰的低密度脂蛋白（LDL）聚集体在未受影响的主动脉内膜细胞的脂质蓄积过程中起关键作用。通过分析光透射波动的相对离散度以及在琼脂糖CL - 2B上进行凝胶过滤证明，经氧化、糖基化、去唾液酸化和丙二醛处理修饰的LDL在培养条件下形成聚集体。天然LDL在相同条件下未能聚集。结果表明，与天然LDL不同，修饰的LDL可使培养细胞的胆固醇酯水平升高2至3倍。此外，观察到脂蛋白聚集程度与积累的胆固醇酯量之间存在直接且强的相关性（r = 0.86）。通过0.1微米滤器过滤或凝胶过滤去除修饰的LDL聚集体可完全防止胆固醇酯在细胞内的积累。这些发现表明，LDL聚集体在体外细胞内脂质积累过程中即使不起决定性作用，也起着至关重要的作用。
