Macromolecular Structure of Arterial Walls

动脉壁的大分子结构

• 批准号: 8344838
• 负责人: Robert Balaban
• 金额: $ 30.45万
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8344838
• 关键词: Affinity; Arterial Fatty Streak; Atherosclerosis; Binding; Binding Sites; Biological Assay; Blood; Blood Vessels; Chemicals; Chondroitin Sulfates; Collagen; Complex; Development; Disease; Disease susceptibility; Elastin; Elements; Fluorescence Microscopy; Goals; Hand; Heparin; Histology; Homologous Gene; Image; Imaging Techniques; Low-Density Lipoproteins; Measures; Methods; Molecular Structure; Mus; Optics; Pattern; Peripheral; Play; Process; Proteins; Sampling; Screening procedure; Structure; Techniques; calcification; coronary sinus valve structure; decorin; design; flexibility; macromolecule; mouse model; novel; novel therapeutic intervention; optical imaging; particle; pre-clinical; pressure; prevent; programs; renal artery; scaffold; submicron; vascular bed

The arterial wall and arterial valves are complex macromolecular structures. One of the major elements of these structures is the scaffold that provides the strength and flexibility to perform the task in hand either retaining the blood in vessels against the arterial pressure or maintaining pressure via the function of coronary valves. In the last several years it has become apparent that the actual microstructure and composition of these macromolecules could influence the progress of different disease states most notably atherosclerosis and value calcification. To gain a better understanding of this process, we have embarked on studies to understand the fine structure of the macromolecules in arterial vascular bed using a novel optical imaging technique that relies on the non-linear excitation (NLE) of collagen and elastin to provide sub-micron images of their structure in unfixed fresh samples together with direct measures of low density lipoprotein particles (LDL) binding using fluorescence microscopy and conventional histology methods. These studies have identified Decorin as a major binding site for LDL in the valve leaflet. Over the last year we have made the following progress: 1) We are currently confirming our studies in the valve leaflet in the more general vascular bed using the renal artery ostia diverter we described two years ago. Protein samples for this vascular structure are being evaluated to establish whether a similar binding pattern discovered in the valves is in play in the peripheral vasculature. 2) Using our screening assay for LDL-Decorin binding, we have been evaluated several molecules for use in a pre-clinical screen in an atheroma prone mouse model. These studies will be designed to look for molecules that interfere with the LDL-Decorin interaction and then evaluate whether these molecules delay or inhibit atheroma formation in the mouse. Currently we have screened and rejected simple chondroitin sulfates and some homologs of heparin as being too low affinity for this purpose, though strong inhibion of binding can be demonstrated at high concentration. Currently we are evaluating several other candidate molecules to accomplish this task as well as evaluating the potential for conducting a more complete chemical screen of this interaction.

动脉壁和动脉瓣是复杂的大分子结构。这些结构的主要元件之一是支架，其提供强度和柔性以执行手头的任务，或者将血液保持在血管中以抵抗动脉压力，或者通过冠状动脉瓣膜的功能来维持压力。在过去的几年中，已经变得明显的是，这些大分子的实际微观结构和组成可以影响不同疾病状态的进展，最显着的是动脉粥样硬化和钙化。为了更好地理解这一过程，我们已经开始研究，利用一种新的光学成像技术来了解动脉血管床中大分子的精细结构，该技术依赖于胶原蛋白和弹性蛋白的非线性激发（NLE），以提供未固定新鲜样本中其结构的亚微米图像，以及低密度脂蛋白颗粒（LDL）的直接测量结合使用荧光显微镜和常规组织学方法。这些研究已经确定核心蛋白聚糖是瓣膜小叶中LDL的主要结合位点。在过去的一年里，我们取得了以下进展：1）我们目前正在确认我们在更广泛的血管床中使用我们两年前描述的肾动脉口分流器的瓣叶研究。正在评价该血管结构的蛋白质样本，以确定在瓣膜中发现的类似结合模式是否在外周血管系统中发挥作用。2)使用我们的LDL-核心蛋白聚糖结合的筛选测定，我们已经评估了几种分子用于在动脉粥样化易感小鼠模型中的临床前筛选。这些研究旨在寻找干扰LDL-核心蛋白聚糖相互作用的分子，然后评估这些分子是否延迟或抑制小鼠动脉粥样硬化形成。目前，我们已经筛选并拒绝了简单的硫酸软骨素和肝素的一些同系物，因为它们对于该目的的亲和力太低，尽管在高浓度下可以证明结合的强抑制。目前，我们正在评估其他几种候选分子来完成这项任务，并评估对这种相互作用进行更完整的化学筛选的潜力。