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: 8269810
• 负责人: M. Reza Ghadiri
• 金额: $ 18.99万
• 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/8269810
• 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.

描述(由申请人提供)：载脂蛋白A-I(apoA-I)是高密度脂蛋白(高密度脂蛋白)的主要蛋白质成分，通过几种生物学机制逆转动物的动脉粥样硬化。血浆盘状核水平升高(前？)高密度脂蛋白颗粒富含载脂蛋白A-I，对人类的动脉粥样硬化和冠心病具有保护作用。人类apoA-I由10个两亲性(或两亲性)？-螺旋(8个22-MERS和2个11-MERS)组成，它们共同作用结合脂质并产生一系列高密度脂蛋白颗粒。有趣的是，18-聚体A类螺旋多肽Ac-DWFKAFYDKVAEKFKEAF-NH2(4F)可以模拟apoA-I的许多功能性质。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，因为我们可能想知道：(1)一个简单的、孤立的螺旋如何能如此好地发挥作用；(2)将这种类型的多个螺旋合并到一个分子实体中会有什么效果。这一提议的一个主要目的是设计具有多种两亲性螺旋的分子，这些分子附着在分子支架上，系统地覆盖2-8个螺旋亚基的范围。我们计划设计、合成、表征和探索能够模拟载脂蛋白A-I的新化学物种。这些纳米材料由不同的支架组成，支架上含有多个两亲性A类螺旋多肽，尺寸在天然高密度脂蛋白(6-12 nm)的尺寸范围内，将在体外单独进行物理表征和生物评价，并以高密度脂蛋白类纳米颗粒(即纳米脂)的形式脂化。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。我们计划研究这些用磷脂包装的设计师材料，如高密度脂蛋白((R)-(+)-1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine)或大豆卵磷脂，以重组高密度脂蛋白(RHDL)颗粒的形式存在。将对低脂(盘状)和富脂(球状)状态下的自组装纳米脂进行研究，以了解其结构和功能，并与4F和天然apoA-I进行比较。我们计划通过体外生物测试评估衍生的高密度脂蛋白类纳米盘的潜在抗动脉粥样硬化特性，例如高密度脂蛋白颗粒重塑和培养细胞的胆固醇外流。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在暴露于血浆后获得的蛋白质组分。这项脂类研究将为以下方面提供有价值的信息：(1)与纳米脂颗粒稳定和形态有关的因素；(2)纳米脂颗粒的结构-功能特性；(3)与高密度脂蛋白相关的蛋白质-脂结合。我们的结果可能为潜在的治疗药物在体内通过消退动脉粥样硬化斑块来治疗动脉粥样硬化建立一个平台。