Investigating IAPP Aggregation and Toxicity using Small Molecule Interference

使用小分子干扰研究 IAPP 聚集和毒性

• 批准号: 7652506
• 负责人: James Hebda
• 金额: $ 2.55万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7652506
• 关键词: Amyloid; Amyloid fibers; Beta Cell; Binding; Biological Assay; Catalysis; Cell Death; Cells; Cessation of life; Data; Extravasation; Hormones; Individual; Insulin; Kinetics; Knowledge; Lead; Lipid Bilayers; Lipid Binding; Lipids; Membrane; Monitor; Non-Insulin-Dependent Diabetes Mellitus; Pancreas; Process; Proteins; Screening procedure; Source; Structure; Structure of beta Cell of islet; Toxic effect; amyloid formation; cell killing; inhibitor/antagonist; islet amyloid polypeptide; new therapeutic target; novel; small molecule

DESCRIPTION (provided by applicant): Islet Amyloid Polypeptide (IAPP) is a 37 residue hormone that is co-secreted with insulin from the Beta cells of the pancreas. IAPP aggregation into amyloid fiber has been implicated in the death of insulin producing Beta cells in Type 2 Diabetes. The mechanisms of IAPP amyloid formation and toxicity are not well understood. Lipid bilayers are potent accelerants of amyloid formation. IAPP has been shown to cause membrane leakage, which is believed to be the source of cell toxicity. I propose to study these processes using small molecules that I have previously identified through a novel screening assay. These compounds' interference with the processes of amyloid formation and membrane leakage will lead to a better understanding of the mechanisms that govern these phenomena. First, small molecules will be characterized to determine the causes of the inhibition of amyloid formation. Lipid catalyzed and de novo (no lipid present) conditions will be used to distinguish between small molecules that specifically inhibit lipid catalysis and general amyloid inhibitors. CD will be used to monitor lipid binding and to identify changes in secondary structure due to small molecule interactions. NMR of 15N IAPP will be used to identify specific interactions between small molecules and IAPP. HSQC spectra will be used to identify individual residues perturbed by these interactions. By comparing NMR and CD data with kinetics, I will assign regions and residues that are important for amyloid formation and lipid binding. Second, I will use membrane leakage as a mimic for cell toxicity to identify compounds that are able to reduce the toxic effects of IAPP. Previous knowledge of the molecular interactions that give rise to amyloid formation and lipid binding will allow identification of the toxic species in amyloid formation, and potentially lead to new therapeutic targets for Type 2 Diabetes. IAPP is a small protein made in the pancreas, in the same cells as insulin. Aggregation of IAPP into amyloid fibers has been implicated in the death of these cells that make insulin in type 2 diabetes. Using small molecules I will investigate how IAPP aggregates and kills cells, as well as open new avenues for the treatment of type 2 diabetes.

描述（由申请人提供）：胰岛淀粉样多肽（IAPP）是一种 37 残基激素，与胰腺 Beta 细胞中的胰岛素共同分泌。 IAPP 聚集成淀粉样纤维与 2 型糖尿病中产生胰岛素的 Beta 细胞的死亡有关。 IAPP 淀粉样蛋白形成和毒性的机制尚不清楚。脂质双层是淀粉样蛋白形成的有效促进剂。 IAPP 已被证明会导致膜渗漏，这被认为是细胞毒性的根源。我建议使用我之前通过新颖的筛选试验鉴定出的小分子来研究这些过程。这些化合物对淀粉样蛋白形成和膜渗漏过程的干扰将有助于更好地理解控制这些现象的机制。首先，对小分子进行表征以确定淀粉样蛋白形成受到抑制的原因。脂质催化和从头（不存在脂质）条件将用于区分特异性抑制脂质催化的小分子和一般淀粉样蛋白抑制剂。 CD 将用于监测脂质结合并识别由于小分子相互作用而引起的二级结构的变化。 15N IAPP 的 NMR 将用于识别小分子和 IAPP 之间的特定相互作用。 HSQC 谱将用于识别受这些相互作用干扰的各个残基。通过将 NMR 和 CD 数据与动力学进行比较，我将指定对淀粉样蛋白形成和脂质结合重要的区域和残基。其次，我将使用膜渗漏作为细胞毒性的模拟，以确定能够减少 IAPP 毒性作用的化合物。先前对引起淀粉样蛋白形成和脂质结合的分子相互作用的了解将有助于识别淀粉样蛋白形成中的有毒物质，并可能导致 2 型糖尿病的新治疗靶点。 IAPP 是一种在胰腺中产生的小蛋白质，与胰岛素位于相同的细胞中。 IAPP 聚集成淀粉样蛋白纤维与这些在 2 型糖尿病中产生胰岛素的细胞的死亡有关。我将利用小分子研究 IAPP 如何聚集和杀死细胞，并为 2 型糖尿病的治疗开辟新途径。