PROTEOGLYCANS, GLYCOSAMINOGLYCANS IN ATHEROSCLEROSIS

我们认为，细胞外基质（ECM）的早期变化， 动脉内膜增厚是由于合成中的修饰 和三种ECM组分的相互作用：多功能蛋白聚糖（CSPG）、透明质酸（HA） 和HA结合蛋白RHAMM（HA介导的运动性受体）。我们 假设动脉平滑肌合成这些成分 肌肉细胞（ASMC）部分受生长因子调节， 生长因子诱导的多功能蛋白聚糖修饰影响粘附 或迁移ASMC。我们将在体外试验中使用 和体内方法，这将集中在人类系统。该提案 包含五个目标，旨在检查这些参与 血管生物学和病理学中的分子。目的我将描述 在核心糖蛋白和GAG链中诱导的结构修饰 多功能蛋白聚糖的有丝分裂原，血小板衍生生长因子（pDGF）， 生长抑制剂，转化生长因子-β 1（TGF-β 1）。两 这些生长因子刺激多功能蛋白聚糖的表达， 将多功能蛋白聚糖与白细胞介素-1（IL-1）诱导的多功能蛋白聚糖进行比较， 下调多功能蛋白聚糖的表达。为此，我们会集中研究 多功能蛋白聚糖和后蛋白聚糖的推定剪接变体的鉴定 连接至的GAG链结构的翻译变化 多功能的。目的二将研究这些生长因子的机制， 细胞因子调节多功能蛋白聚糖的表达。因此，实验已经 旨在探讨多功能蛋白聚糖表达的调控是否涉及 转录或转录后事件，以及生长因子 独立调节多功能蛋白聚糖蛋白和GAG合成。第三 目的，我们将研究是否HA和RHAMM的合成，相互作用 与多功能蛋白聚糖形成大分子复合物， 关于Versican我们也将确定是否形成这样的 大分子复合物对ASMC的组装和扩张至关重要 或影响ASMC迁移。第四个目标是 测试多功能蛋白聚糖和HA是否调节血管细胞粘附，以及是否 versican中的特定域负责调解 与细胞表面或基质配体的相互作用。最后一个目标将 确定多功能蛋白聚糖、HA和RHAMM是否表达并沉积在 特定的时间或空间模式，其特征在于 血管病变的发展。在这项工作中，我们将重点关注 检查动脉损伤后形成的病变， 血管再狭窄我们还将测试是否改变 多功能蛋白聚糖在血管损伤中的表达影响损伤的发展。 确定调节这些表达的机制， 大分子和研究，旨在检查之间的关系， 它们的结构和它们在血管组织中的功能提供了 潜在的靶向治疗干预和中断 血管病变发展。

We propose that early changes in the extracellular matrix (ECM) that lead to arterial intimal thickening are due to modifications in the synthesis and interaction of three ECM components: versican (CSPG), hyaluronan (HA) and an HA-binding protein, RHAMM (receptor for HA-mediated motility). We hypothesize that the synthesis of these components by arterial smooth muscle cells (ASMC) is regulated in part by growth factors and that the modifications induced in versican by growth factors influence the adhesion or migration of ASMC. We will test these hypotheses using both in vitro and in vivo approaches, which will focus on human systems. The proposal contains five aims and is designed to examine the involvement of these molecules in vascular biology and pathology. Aim I will characterize the structural modifications induced in the core glycoprotein and GAG chains of versican by the mitogen, platelet-derived growth factor (pDGF), and the growth inhibitor, transforming growth factor-beta1 (TGF-beta1). Both of these growth factors stimulate versican expression, and their effects on versican will be compared to those induced by interleukin-1(IL-1), which down-regulates versican expression. In this aim, we will focus on the identification of putative splice variants of versican and post- translational changes in the structure of the GAG chain attached to versican. Aim II will examine the mechanisms by which these growth factors and cytokines regulate versican expression. Thus, experiments have been designed to ask whether regulation of versican expression involves transcriptional or post-transcriptional events, and whether growth factors independently regulate versican protein and GAG synthesis. In the third aim, we will examine whether the synthesis of HA and RHAMM, which interact with versican to form macromolecular complexes, is regulated in parallel with versican. We will also ascertain whether the formation of such macromolecular complexes is critical to the assembly and expansion of ASMC pericellular matrix, or influences ASMC migration. The fourth aim will test whether versican and HA regulate vascular cell adhesion, and whether specific domains within versican are responsible for mediating interactions with cell surface or matrix ligands. The last aim will determine whether versican, HA and RHAMM are expressed and deposited in specific temporal or spatial patterns that characterize specific phases in the development of vascular lesions. In this work, we will focus on the examination of lesions that form following arterial injury and during vascular restenosis. We will also test whether altering the pattern of versican expression in vascular lesions influences lesion development. Identification of the mechanism(s) that regulate the expression of these macromolecules and studies designed to examine the relationships between their structure and their function within vascular tissue offer the potential for targeted therapeutic intervention and interruption of vascular lesion development.