Defining Vascular Functions of Proteoglycans through Chemical Biology Approaches

项目总结(见说明)； 蛋白多糖是最复杂的糖结合物，在血管系统中起着关键作用。它们由一个 具有两个或更多个糖胺多聚糖(GAG)侧链的蛋白质部分， 硫酸软骨素(CS)、皮肤素硫酸盐(DS)和角蛋白硫酸盐(KS)。HS是研究最广泛的 在所有的笑话中。HS的精细结构，包括其硫化模式、异构化和结构域 组织，极大地影响它们与各种各样的蛋白质结合的能力，包括生长因子， 蛋白水解酶、蛋白水解酶抑制剂、黏附蛋白、趋化因子和细胞因子 调节各种血管病理生理过程，如止血、血栓形成、缺氧、脓毒症、 炎症和血管生成。Gag-蛋白质、Gag-细胞和Gag-ECM的相互作用被证明是 在这些血管病理状态期间调节失调，加剧了疾病的状况。这些 异常的相互作用归因于蛋白多糖和蛋白多糖表达的增加或减少 他们的重塑酶，如细胞外硫酸酯酶，以及他们增加的内皮脱落 细胞。我们对调节这些相互作用的HS精细结构和调节HS的因素的了解 疾病进展过程中的生物合成将提高我们利用 HS在对抗血管疾病方面的作用。此外，了解GAG多价性的重要性将 引导我们微调细胞过程，以改善血管疾病。在此应用程序中，我们 建议(A)使用最初由PI开发的酶策略来组装一组HS结构 确定与凝血酶相互作用所必需的结构参数，以及 细胞因子/趋化因子，(B)通过刺激GAG的生物合成来利用其治疗潜力 使用合成支架模拟蛋白多糖和(C)调节HS生物合成，以更好地定义 HS硫酸盐化模式在血管生成中的作用 相关性(请参阅说明)： 血管损伤是美国最令人衰弱和最主要的死亡原因之一。此外，他们还 占全国医疗保健总成本的第一位。目前有数量有限的药物 其中肝素是最广泛使用的抗凝剂，但它有许多副作用。这 该提案旨在从分子水平上了解类肝素分子的生物学作用，以及 调节其生物合成的因素，最终目标是开发心血管药物。

PROJECT SUMMARY (See instructions); Proteoglycans are the most complex glycoconjugates that play pivotal roles in vasculature. They consist of a protein moiety with two or more glycosaminoglycan (GAG) side chains such as heparan sulfate (HS), chondroitin sulfate (CS), dermatan sulfate (DS) and keratan sulfate (KS). HS is the most widely studied among all GAGs. The fine structures of HS, in terms of their sulfation pattern, epimerization and domain organization, dramatically affect their ability to bind to a wide variety of proteins, including growth factors, proteases, protease inhibitors, adhesive proteins, chemokines and cytokines, which in turn are shown to regulate various vascular pathophysiological processes such as hemostasis, thrombosis, hypoxia, sepsis, inflammation and angiogenesis. GAG-protein, GAG-cell and GAG-ECM interactions are shown to be dysregulated during these vascular pathological conditions exacerbating the disease conditions. These dysregulated interactions are attributed to both increased or decreased expression of proteoglycans and their remodeling enzymes such as extracellular sulfatases as well their increased shedding from endothelial cells. Our knowledge of HS fine structures that regulate these interactions and factors that regulate HS biosynthesis during the disease progression will advance our ability to harness the therapeutic potential of HS in combating vascular diseases. In addition, understanding the importance of GAG multivalency will guide us in fine tuning the cellular processes to ameliorate vascular disorders. In this application, we propose to (a) use enzymatic strategy, originally developed by the PI, to assemble a panel of HS structures to determine the structural parameters that are essential for interactions with coagulation proteases and cytokines/chemokines, (b) to harness the therapeutic potential of GAGs through stimulating the biosynthesis of proteoglycan mimetics using synthetic scaffolds and (c) to modulate HS biosynthesis to better define the role of HS sulfation pattern in angiogenesis. RELEVANCE (See instructions): Vascular injuries are among the most debilitating and leading causes of deaths in USA. Furthermore, they represent number one in the total national health care cost. Currently there are a limited number of drugs available of which heparin is most widely used as anticoagulant though it has numerous side effects. This proposal aims to understand the biological role of heparin like molecules at the molecular level and the factors that regulate their biosynthesis with the final goal of developing cardiovascular drugs.