PROTEOGLYCANS, GLYCOSAMINOGLYCANS AND ATHEROSCLEROSIS

蛋白聚糖、糖胺聚糖和动脉粥样硬化

• 批准号: 6353045
• 负责人: Thomas N Wight
• 金额: $ 26.64万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-30 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6353045
• 关键词: apolipoproteins; atherosclerosis; atherosclerotic plaque; cellular pathology; chondroitin sulfates; dietary lipid; extracellular matrix; human tissue; hyaluronate; laboratory mouse; laboratory rat; lectin; low density lipoprotein; mucopolysaccharides; protein binding; protein protein interaction; proteoglycan; tissue /cell culture; vascular smooth muscle

Abstract: Previous work indicates the versican, the major vascular interstitial chondroitin sulfate proteoglycan (CSPG), and the glycosaminoglycan, hyaluronan (HA), which interacts with versican, accumulate in the extracellular matrix (ECM) in early atherosclerotic and restenotic lesions. We have also shown that the synthesis of these two molecules is highly regulated by specific growth factors and cytokines and is modulated when arterial smooth muscle cells (ASMC) are stimulated to migrate and proliferate. Inhibition of the interaction of versican and HA with receptors at the cell surface blocks ASMC proliferation and migration. One consequence of versican accumulation in the ECM is the trapping and retention of lipoproteins. We have shown that versican interacts with apoB and apoE-containing lipoproteins and this interaction is enhanced by factors that influence chondroitin sulfate chain biosynthesis. These observations have led us to continue to explore the importance of versican/HA complexes in the ECM in the regulation of ASMC phenotype, and in the retention of lipoproteins in the vascular wall. We hypothesize that modifications in versican/HA synthesis are required for ASMC proliferation and migration, and that these modifications influence other properties of ASMC, such as the ability to remodel the ECM during different phases of atherogenesis. We further postulate that the accumulation of versican within the ECM is partly responsible for the extracellular accumulation of lipoproteins. We propose to examine these hypotheses in four aims. The first aim will address questions concerning the role of versican and versican isoform expression in the regulation of ASMC phenotype and matrix remodeling. In this work we will express versican isoforms and mini-genes that contain various domains of versican, and examine the effect on cell proliferation, migration and matrix protein deposition. The second aim includes experiments designed to examine the expression of HA synthases by ASMC, and the role of HA, both as an extracellular component of the matrix and as a newly discovered intracellular molecule, in ASMC proliferation, migration and ECM remodeling. The third aim is designed to extend our studies concerning the interaction of lipoproteins with versican chondroitin sulfate side chains. We propose to determine the specific oligosaccharide sequences that are responsible for the binding of ApoB and ApoE-contain lipoproteins to versican, and determine factors that induce changes in chondroitin sulfate chain structure that give rise to versican forms with differing affinities for lipoproteins. In the fourth aim, we will use new reagents to examine the presence of versican variants and proteolytic cleavage products in naturally-occurring atherosclerotic lesions, investigate the effect of altered expression of versican variants and HA synthases on lesion progression by a cell-mediated gene transfer approach in the injured rat carotid neointimal model, and use targeted over-expression of versican variants in a fat-fed transgenic mouse model to examine the role of versican expression on the accumulation of lipoproteins in vascular lesions in vivo. Manipulation of versican and HA metabolism should influence the progression and/or regression of atherosclerotic lesion development.

摘要：先前的研究表明，多功能蛋白聚糖（主要的血管间质硫酸软骨素蛋白聚糖（CSPG））以及与多功能蛋白聚糖相互作用的糖胺聚糖透明质酸（HA）在早期动脉粥样硬化和再狭窄病变的细胞外基质（ECM）中积聚。我们还表明，这两种分子的合成受到特定生长因子和细胞因子的高度调节，并在刺激动脉平滑肌细胞（ASMC）迁移和增殖时受到调节。抑制多功能蛋白聚糖和 HA 与细胞表面受体的相互作用可阻止 ASMC 增殖和迁移。多功能蛋白聚糖在 ECM 中积累的后果之一是脂蛋白的捕获和保留。我们已经证明多功能蛋白聚糖与含有 apoB 和 apoE 的脂蛋白相互作用，并且影响硫酸软骨素链生物合成的因素增强了这种相互作用。这些观察结果促使我们继续探索 ECM 中多功能蛋白聚糖/HA 复合物在调节 ASMC 表型以及在血管壁中保留脂蛋白方面的重要性。我们假设多功能蛋白聚糖/HA 合成的修饰是 ASMC 增殖和迁移所必需的，并且这些修饰影响 ASMC 的其他特性，例如在动脉粥样硬化形成的不同阶段重塑 ECM 的能力。我们进一步假设 ECM 内多功能蛋白聚糖的积累是脂蛋白细胞外积累的部分原因。我们建议通过四个目标来检验这些假设。第一个目标将解决有关多功能蛋白聚糖和多功能蛋白聚糖亚型表达在 ASMC 表型和基质重塑调节中的作用的问题。在这项工作中，我们将表达多功能蛋白聚糖亚型和包含多功能蛋白聚糖各个结构域的小基因，并检查其对细胞增殖、迁移和基质蛋白沉积的影响。第二个目标包括旨在检查 ASMC 表达 HA 合酶的实验，以及 HA 作为基质的细胞外成分和新发现的细胞内分子在 ASMC 增殖、迁移和 ECM 重塑中的作用。第三个目标是扩展我们关于脂蛋白与多功能硫酸软骨素侧链相互作用的研究。我们建议确定负责含有 ApoB 和 ApoE 的脂蛋白与多功能蛋白聚糖结合的特定寡糖序列，并确定诱导硫酸软骨素链结构变化的因素，从而产生对脂蛋白具有不同亲和力的多功能蛋白聚糖形式。在第四个目标中，我们将使用新试剂来检查自然发生的动脉粥样硬化病变中多功能蛋白聚糖变体和蛋白水解裂解产物的存在，通过细胞介导的基因转移方法在受伤的大鼠颈动脉新内膜模型中研究多功能蛋白聚糖变体和HA合酶的表达改变对病变进展的影响，并在损伤大鼠颈动脉新内膜模型中使用多功能蛋白聚糖变体的靶向过度表达。 脂肪喂养的转基因小鼠模型，用于检查多功能蛋白聚糖表达对体内血管病变中脂蛋白积累的作用。控制多功能蛋白聚糖和HA代谢应影响动脉粥样硬化病变发展的进展和/或消退。