Synthesis and Application of Novel Apolipoprotein Mimetics

新型载脂蛋白模拟物的合成及应用

• 批准号: 8110380
• 负责人: M. Reza Ghadiri
• 金额: $ 33.23万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2013-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8110380
• 关键词: Adopted; Animals; Anti-Inflammatory Agents; Antiatherogenic; Antioxidants; Apolipoprotein A-I; Apolipoproteins; Apolipoproteins A; Architecture; Area; Arterial Fatty Streak; Atherosclerosis; Biological; Biological Assay; Cardiovascular Diseases; Cardiovascular system; Cells; Chemicals; Cholesterol; Collection; Coronary heart disease; Data; Development; Dimensions; Evaluation; Event; Exposure to; Goals; Heart Diseases; Hepatocyte; High Density Lipoproteins; Human; In Vitro; Lead; Lecithin; Lipid Binding; Lipids; Molecular; Molecular Conformation; Morphology; Mus; Nanostructures; Patients; Peptides; Pharmaceutical Preparations; Phosphatidylcholine-Sterol O-Acyltransferase; Phospholipids; Phosphorylcholine; Plasma; Property; Proteins; Proteomics; Recombinants; Relative (related person); Research; Research Personnel; Research Proposals; Resolution; Roentgen Rays; Series; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Staging; Structure; Techniques; Tertiary Protein Structure; Testing; Therapeutic Agents; combat; design; dimer; hepatoma cell; in vitro Bioassay; in vivo; insight; interest; macrophage; meetings; mimetics; molecular array; nanodisk; nanomaterials; nanoparticle; next generation; novel; packaging material; particle; scaffold; soy; tool; trend

DESCRIPTION (provided by applicant): Apolipoprotein A-I (apoA-I), the major protein component of high-density lipoprotein (HDL), regresses atherosclerosis in animals by several biological mechanisms. Elevated plasma levels of discoidal (pre-?) HDL particles, which are rich in apoA-I, protect against atherosclerosis and coronary heart disease in humans. Human apoA-I is comprised of 10 amphiphilic (or amphipathic) ?-helices (eight 22-mers and two 11-mers) that act together to bind lipids and engender a range of HDL particles. Interestingly, the 18-mer amphiphilic, class A, ?-helical peptide Ac-DWFKAFYDKVAEKFKEAF-NH2 (4F) can mimic many of apoA-I's functional properties. The dramatic difference between the apoA-I and 4F molecules raises important questions about structure vs. function in that we may wonder: (1) how a simple, isolated helix can function so well and (2) what would be the effect of incorporating multiple helices of this type into a single molecular entity. A principal aim of this proposal is to devise molecules with a multiplicity of amphiphilic ?-helices that are attached to a molecular scaffold, covering a range of 2-8 helical subunits systematically. We propose to design, synthesize, characterize, and explore novel chemical species that can mimic apoA-I. These nanomaterials, composed of a distinct scaffold bearing multiple, amphiphilic, class A ?-helical peptides, of appropriate dimensions in the size domain of native HDL (6-12 nm), will be physically characterized and biologically evaluated in vitro, alone and lipidated in the form of HDL-like nanoparticles (i.e. nanolipids). The structures of interest will constitute dimers, trimers, tetramers, hexamers, and octamers with linear and branched chain topologies. We plan to investigate these designer materials packaged with phospholipid, such as (R)-(+)-1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or soy lecithin, in the form of recombinant HDL (rHDL) particles. Studies will be conducted on the self-assembled nanolipids in lipid-poor (discoidal) and lipid-rich (spherical) states, with and without cholesterol present, to gain insight into structure and function, in comparison with 4F and native apoA-I. We plan to assess the potential antiatherogenic properties of derived HDL-like nanodiscs via in vitro bioassays, such as HDL particle remodeling and cholesterol efflux from cells in culture. We plan to analyze our designer nanolipids for acquired protein components after their exposure to plasma by using proteomics techniques (e.g. MALDI-TOF MS). This lipidology research should provide valuable information on: (1) factors involved in nanolipid particle stabilization and morphology, (2) structure-function properties of nanolipid particles, and (3) protein-lipid association that is relevant to HDL. Our results may establish a platform for potential therapeutic agents to treat atherosclerosis by the regression of atherosclerotic plaque in vivo. PUBLIC HEALTH RELEVANCE: In human studies, elevated plasma levels of apoA-I, the major protein in HDL, correlated inversely with the development of coronary heart disease. We propose to design, synthesize, and explore specific molecular entities that can mimic apoA-I. This project could provide a blueprint for new drugs to combat heart disease.

描述（由申请人提供）： 载脂蛋白 A-I (apoA-I) 是高密度脂蛋白 (HDL) 的主要蛋白质成分，通过多种生物学机制逆转动物动脉粥样硬化。血浆中富含 apoA-I 的盘状（前？）HDL 颗粒水平升高，可预防人类动脉粥样硬化和冠心病。人 apoA-I 由 10 个两亲性（或两亲性）β-螺旋（8 个 22 聚体和两个 11 聚体）组成，它们共同作用以结合脂质并产生一系列 HDL 颗粒。有趣的是，18 聚体两亲性 A 类 β-螺旋肽 Ac-DWFKAFYDKVAEKFKEAF-NH2 (4F) 可以模拟 apoA-I 的许多功能特性。 apoA-I 和 4F 分子之间的巨大差异引发了关于结构与功能的重要问题，我们可能想知道：（1）一个简单的、孤立的螺旋如何能够如此良好地发挥作用，以及（2）将这种类型的多个螺旋合并到单个分子实体中会产生什么效果。该提案的主要目的是设计具有多个两亲性β-螺旋的分子，这些分子附着在分子支架上，系统地覆盖一系列2-8个螺旋亚基。我们建议设计、合成、表征和探索可以模仿 apoA-I 的新型化学物质。这些纳米材料由具有多个两亲性 A 类 β-螺旋肽的独特支架组成，其尺寸在天然 HDL 的尺寸范围内（6-12 nm）（6-12 nm），将在体外单独进行物理表征和生物学评估，并以类 HDL 纳米粒子（即纳米脂质）的形式进行脂质化。感兴趣的结构将构成具有线性和支链拓扑的二聚体、三聚体、四聚体、六聚体和八聚体。我们计划研究这些以重组 HDL (rHDL) 颗粒形式包装的设计材料，例如 (R)-(+)-1-棕榈酰-2-油酰-sn-甘油-3-磷酸胆碱 (POPC) 或大豆卵磷脂。将对贫脂（盘状）和富脂（球形）状态的自组装纳米脂质（存在或不存在胆固醇）进行研究，以与 4F 和天然 apoA-I 进行比较，以深入了解其结构和功能。我们计划通过体外生物测定评估衍生的 HDL 样纳米盘的潜在抗动脉粥样硬化特性，例如 HDL 颗粒重塑和培养细胞中的胆固醇流出。我们计划使用蛋白质组学技术（例如 MALDI-TOF MS）分析我们设计的纳米脂质在暴露于血浆后获得的蛋白质成分。这项脂质学研究应提供以下方面的有价值的信息：(1) 纳米脂质颗粒稳定和形态相关的因素，(2) 纳米脂质颗粒的结构功能特性，以及 (3) 与 HDL 相关的蛋白质-脂质关联。我们的结果可能为潜在的治疗药物建立一个平台，通过体内动脉粥样硬化斑块的消退来治疗动脉粥样硬化。 公共健康相关性：在人类研究中，高密度脂蛋白 (HDL) 中的主要蛋白质 apoA-I 的血浆水平升高与冠心病的发展呈负相关。我们建议设计、合成和探索可以模拟 apoA-I 的特定分子实体。该项目可以为治疗心脏病的新药提供蓝图。