PROTEOGLYCANS, GLYCOSAMINOGLYCANS IN ATHEROSCLEROSIS

我们认为，早期细胞外基质(ECM)的变化导致 动脉内膜增厚是由于合成中的修饰 以及三种ECM成分的相互作用：Verscan(CSPG)，透明质酸(HA) 以及一种HA结合蛋白，RHAMM(HA介导的运动性受体)。我们 假设这些成分的合成由动脉平滑 肌肉细胞(ASMC)在一定程度上受生长因子的调节， 生长因子诱导的Verscan修饰对粘附性的影响 或ASMC的迁移。我们将在体外使用这两种方法来检验这些假说 以及体内方法，将重点放在人类系统上。这项建议 包含五个目标，旨在检查这些目标的参与 血管生物学和病理学中的分子。Aim我将描述 核糖蛋白和Gag链引起的结构修饰 有丝分裂原、血小板衍生生长因子(PDGF)和 生长抑制因子转化生长因子-β1(转化生长因子-β1)。两个都是 这些生长因子刺激多种多样的表达，以及它们对 Verscan将与白细胞介素1(IL-1)诱导的细胞因子进行比较，后者 下调杂乱无章的表达。在这个目标中，我们将重点关注 VERSICAN和POST-2基因剪接变异体的鉴定 结合在一起的Gag链结构的翻译变化 维西嘉。AIM II将研究这些生长因子通过哪些机制 细胞因子调节变态蛋白的表达。因此，实验已经被 旨在询问对杂乱无章的表达的监管是否包括 转录或转录后事件，以及生长因子 独立调节杂蛋白和GAG的合成。在第三节 目的，我们将考察HA和RHAMM的合成是否相互作用 与万西康形成大分子络合物，是平行调节的 和凡西嘉一起。我们也会确定这种情况的形成 大分子复合体是ASMC组装和扩张的关键 细胞外基质，或影响ASMC迁移。第四个目标将是 检测Verscan和HA是否调节血管细胞黏附，以及 Verscan内的特定域负责调解 与细胞表面或基质配体的相互作用。最终的目标将是 确定VERSICAN、HA和RHAMM是否在 表征特定阶段的特定时间或空间模式 血管病变的发展。在这项工作中，我们将重点关注 动脉损伤后和损伤期间形成的病变的检查 血管再狭窄。我们还将测试是否改变了 VERSICAN在血管病变中的表达影响病变的发展。 调控这些基因表达的机制的确定(S) 大分子和旨在研究它们之间关系的研究 它们的结构和在血管组织中的功能提供了 靶向治疗干预的可能性和阻断 血管病变的发展。

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.