The Role of Heparan Sulfate in Vascular Remodeling

性状（由申请方提供）：硫酸乙酰肝素蛋白聚糖（HSPG）由共价连接至硫酸乙酰肝素（HS）链的蛋白聚糖核心蛋白组成。这些HS链含有许多趋化因子和生长因子的结合位点。一个新兴的证据表明，趋化因子和生长因子结合和活性的特异性取决于硫酸化表位沿着HS链长度的独特模式。我们已经证明，血管损伤调用显着的变化，在模式的硫酸化表位沿着HS链利用一个敏感的国家的最先进的HPLC为基础的方法。这些变化伴随着调节HS硫酸化的酶的表达的强烈增加。起始硫酸化反应由N-脱乙酰基-N-磺基转移酶（NDST）家族催化。我们发现，在小鼠血管损伤后，最常见的亚型NDST 1增加了20倍。本修订提案的总体目标是确定HS硫酸化在血管损伤中的作用。为此，我们将采用新的遗传小鼠模型，靶向删除平滑肌中的NDST 1，如果必要的话，额外的靶向条件性删除调节HS硫酸化和合成的酶。遗传和生化方法的组合将在体内和体外沿着使用新建立的基于FACS的方法，以仔细定义HS硫酸化如何影响损伤后的重塑过程。具体来说，我们将：测试假设，减少HS硫酸导致减少损伤形成的反应。二.检验HS硫酸化减少会损害趋化因子结合、表达和活性的假设。了解HS结构和功能在体内的操纵如何影响血管重塑，通过设计特异性修饰HS的新型合成化合物，在治疗血管疾病方面可能具有显著的治疗价值。这些研究将提供第一个关键的看看在血管平滑肌细胞的损伤程度和趋化因子的调节内源性HS结构的影响。

DESCRIPTION (provided by applicant): Heparan sulfate proteoglycans (HSPG) consist of a proteoglycan core protein covalently attached to heparan sulfate (HS) chains. These HS chains contain binding sites for numerous chemokines and growth factors. An emerging body of evidence suggests that specificity of chemokine and growth factor binding and activity is dependent upon the unique patterning of sulfated epitopes along the length of the HS chains. We have demonstrated that vascular injury invokes significant changes in the pattern of sulfated epitopes along the HS chains utilizing a sensitive state-of-the-art HPLC-based approach. These changes were accompanied by robust increases in the expression of enzymes that regulate HS sulfation. The initial sulfation reaction is catalyzed by a family of N-deacetylase-N-sulfotransferases (NDSTs). We identified a 20- fold increase in the most prevalent isoform, NDST1, following vascular injury in mice. The overall goal of this revised proposal is to establish the role of HS sulfation in vascular injury. To do this we will employ novel genetic murine models with targeted deletion of NDST1 in smooth muscle, and if necessary, additional targeted conditional deletions of enzymes that regulate HS sulfation and synthesis. A combination of genetic and biochemical approaches will be used in vivo and in vitro along with a newly established FACS-based approach to carefully define how HS sulfation influences the process of remodeling in response to injury. Specifically, we will: Test the hypothesis that decreasing HS sulfation leads to a reduction in lesion formation in response to injury. II. Test the hypothesis that decreasing HS sulfation impairs chemokine binding, expression, and activity. Understanding how the manipulation of HS structure and function in vivo affects vascular remodeling could have significant therapeutic value in treating vascular disease through the design of novel synthetic compounds that specifically modify HS. These studies will provide the first critical look at the impact of endogenous HS structure in vascular smooth muscle cells on the extent of injury and the regulation of chemokines.