LDL-Proteoglycans Complex as a fatty strek site in atherosclerosis.

低密度脂蛋白-蛋白聚糖复合物作为动脉粥样硬化中的脂肪运动部位。

• 批准号: 09670741
• 负责人: HAMADA Masanori
• 金额: $ 2.05万
• 依托单位: Wakayama Medical Collage
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09670741/
• 关键词: 動脈硬化; glycosaminoglycans; low density lipoprotein

Objective : It has been reported that low density lipoprotein(LDL) produce insoluble complex with mono-sulfated glycosamino-glycans(GAGs). The complex also has a high affinity with calcium binding proteins namely osteopontin(OPN). We reported that the GAGs are increased in the aorta of experimental models of hypertension in rat. The main aim of this experiment was to investigate how the increased GAGs react with LDL to make insoluble GAGs-LDL complex at the site of atheroscleritic lesion and how the OPN is controled by angiotensin II.Design and Methods : 96-well microtiteation plate was coated with a certain amount of LDL. A limiting quantity of biotin-conjugated proteoglycans(PrG) is allowed to bind to each coated well in competition with different kind of GAGs or lipoproteins applied during incubation period. The amount of biotin-conjugated PrG retained on well was estimated spectrophotometrically by alkaline phosphatase-avidin method. The OPN produced in the culture medium by cultur … More ed vascular smooth muscle cells are measured by Western blotting with monoclonal antibody to OPN.Results : Lp(a) and very low density lipoprotein (VLDL) showed higher affinity with chondroitin-PrG than LDL and high density lipoprotein(HDL) but not significantly. Heparin showed significantly higher affinity with chondroitin-PrG than hiarulonic acid, heparan sulfate and chondroitin sulfate. Divalent cations(calcium, magnesium or manganese) were important to obtain insoluble GAGs-LDL complex in this in vitro model. Angiotensin II increased OPN protein in the medium in accordance with the concentrations between 10ィイD2-11ィエD2M to 10ィイD2-7ィエD2M. Whereas Sar-Ala angiotensin II did not. Angiotensin II receptor blockade supressed OPN increase produced by angiotensin II completely at a concentration of 10ィイD2-5ィエD2M.Conclusions : Our results showed that GAGs and divalent cations are essential for LDL to remain in the atherosclerotic lesion. Hypertension might contribute to make the complex by enhance production of chondroitin sulfate in the aortic media. Angiotensin II might enhance hydroxyapatite formation in hypertensive atherosclerotic lesion. Less

目的：低密度脂蛋白（LDL）与单硫酸化糖胺聚糖（GAG）形成不溶性复合物。该复合物还与钙结合蛋白即骨桥蛋白（OPN）具有高亲和力。本文报道了实验性高血压大鼠主动脉中糖胺聚糖的含量增加。本实验的主要目的是研究在动脉粥样硬化病变部位增加的糖胺聚糖（GAGs）如何与低密度脂蛋白（LDL）反应形成不溶性的GAGs-LDL复合物，以及血管紧张素Ⅱ（Ang Ⅱ）如何调控骨桥蛋白（OPN）。允许有限量的生物素缀合的蛋白聚糖（PrG）与在孵育期间应用的不同种类的GAG或脂蛋白竞争结合到每个包被的孔。通过碱性磷酸酶-亲和素法，通过生物素定量法估计保留在孔上的生物素缀合的PrG的量。培养液中产生的骨桥蛋白， ...更多信息 结果：Lp（a）和极低密度脂蛋白（VLDL）与软骨素-PrG的亲和力高于低密度脂蛋白（LDL）和高密度脂蛋白（HDL），但差异不显著。肝素与软骨素-PrG的亲和力显著高于黄曲霉酸、硫酸乙酰肝素和硫酸软骨素。二价阳离子（钙、镁或锰）对于在该体外模型中获得不溶性GAGs-LDL复合物是重要的。血管紧张素II在10 μ mol/L D2-11 μ mol/L D2 M至10 μ mol/L D2-7 μ mol/L D2 M浓度范围内增加培养液中OPN蛋白的表达。而Sar-Ala血管紧张素II则没有。在10 μ mol/L D2-5 μ mol/L D2 M浓度下，血管紧张素Ⅱ受体阻断剂完全抑制血管紧张素Ⅱ引起的OPN增加。结论：GAGs和二价阳离子是LDL在动脉粥样硬化病变中滞留的必要条件。高血压可能通过增加主动脉中膜硫酸软骨素的产生而促进复合物的形成。血管紧张素II可能促进高血压动脉粥样硬化病变中羟基磷灰石的形成。少

项目成果

S.Booka,M.Hamada: "Glycosaminoglycans enhmces lipid accumulation in hypertension" J.of Hypertension. 61s. 321 (1998)

S.Booka，M.Hamada：“糖胺聚糖增强高血压中的脂质积累”J.of Hypertension。