Srinivasan S R, Vijayagopal P, Eberle K, Dalferes E R, Radhakrishnamurthy B, Berenson G S
Department of Medicine, Louisiana State University Medical Center, New Orleans.
Atherosclerosis. 1988 Jul;72(1):1-9. doi: 10.1016/0021-9150(88)90056-1.
Although the selective interaction of low density lipoproteins (LDL) with arterial proteoglycans is known, information is lacking on LDL-binding affinity of different subspecies occurring within a proteoglycan family. Isomeric chondroitin sulfate proteoglycan preparations sedimenting at densities of 1.54 g/ml (D1), 1.50 g/ml (D2) and 1.46 g/ml (D3) were isolated from bovine aorta intima-media under dissociative conditions and subjected to equilibrium binding to LDL-agarose gel. D1, D2 and D3 contained 36%, 37% and 11% dermatan sulfate, respectively. Sulfate to hexosamine ratio was low (0.73) in D1 when compared to D2 and D3 (0.94 and 1.04). Of the total proteoglycans contained in D1, D2 and D3, 41%, 52% and 66% interacted with LDL, respectively. LDL-bound proteoglycans dissociated over a wide range of ionic strengths (0.15-1.0); in comparison, LDL-bound heparin dissociated within a narrow range (0.5-0.75). Unlike other preparations, 30% of bound D3 dissociated at an ionic strength of 1.0. In D1 and D2 the proportion of dermatan sulfate increased in proteoglycan fractions that were bound firmly to LDL, whereas a high affinity fraction in D3 contained no dermatan sulfate. Thus, isomeric chondroitin sulfate proteoglycans display considerable divergence with respect to LDL binding. This may depend not only on the degree of sulfation but on other characteristics of the chondroitin sulfate isomers as well.
尽管低密度脂蛋白（LDL）与动脉蛋白聚糖之间的选择性相互作用已为人所知，但关于蛋白聚糖家族中不同亚类的LDL结合亲和力的信息却很缺乏。在解离条件下，从牛主动脉内膜中分离出密度分别为1.54 g/ml（D1）、1.50 g/ml（D2）和1.46 g/ml（D3）的硫酸软骨素蛋白聚糖异构体制剂，并使其与LDL-琼脂糖凝胶进行平衡结合。D1、D2和D3分别含有36%、37%和11%的硫酸皮肤素。与D2和D3（0.94和1.04）相比，D1中的硫酸根与己糖胺的比率较低（0.73）。D1、D2和D3中所含的总蛋白聚糖分别有41%、52%和66%与LDL相互作用。与LDL结合的蛋白聚糖在很宽的离子强度范围内（0.15 - 1.0）解离；相比之下，与LDL结合的肝素在较窄的离子强度范围内（0.5 - 0.75）解离。与其他制剂不同，30%与LDL结合的D3在离子强度为1.0时解离。在D1和D2中，与LDL紧密结合的蛋白聚糖组分中硫酸皮肤素的比例增加，而D3中的高亲和力组分不含硫酸皮肤素。因此，硫酸软骨素蛋白聚糖异构体在LDL结合方面表现出相当大的差异。这可能不仅取决于硫酸化程度，还取决于硫酸软骨素异构体的其他特性。
