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Lipoate Derivatives Targeting Alzheimer's Amyloid

靶向阿尔茨海默病淀粉样蛋白的硫辛酸衍生物

基本信息

批准号：
7473116
负责人：
XUDONG HUANG
金额：
$ 18.22万
依托单位：
BRIGHAM AND WOMEN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-08-01 至 2010-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7473116
关键词：
Affinity Alzheimer&apos s Disease Alzheimer&apos s disease model Amyloid Amyloid beta-Protein Amyloidosis Animals Antioxidants Applications Grants Attenuated Behavior Binding Biological Assay Blood - brain barrier anatomy Brain Cells Cerebrum Ceruloplasmin Chelating Agents Chelation Therapy Clinical Clioquinol Coupled Cultured Cells Data Deferoxamine Development Disease Disease model Dose Edetic Acid Enzyme-Linked Immunosorbent Assay Fluorescence Microscopy Goals Human Hydrogen Bonding Hydrogen Peroxide Immunohistochemistry In Vitro Inbred C57BL Mice Luciferases Measures Mediating Metals Molecular Mus Neuroblastoma Neurons Octanols Oxidative Stress Partition Coefficient Penetration Pentetic Acid Peptides Proteins Range Rattus Reactive Oxygen Species Research Roentgen Rays Safety Senile Plaques Senile dementia Solutions Specificity Surface Plasmon Resonance Techniques Testing Therapeutic Therapeutic Agents Thioctic Acid Toxic effect Trace Elements Transgenic Mice Translations Untranslated Regions Vitamin E Water Wild Type Mouse amyloid pathology base benzothiazole brain tissue catalase chelation concept copper-binding protein design drug development drug discovery human disease in vivo instrument laser capture microdissection lipoate liquid chromatography mass spectrometry luminescence neurotoxicity novel peptide A pharmacophore time interval

项目摘要

DESCRIPTION (provided by applicant): The clinical benefits of current antioxidant/metal chelation therapies for Alzheimer's disease (AD), the most common form of senile dementia, are limited due to their poor disease target specificity. Moreover, the exact subserving mechanism(s) of antioxidant/metal chelation effects upon AD amyloid pathology are not clear. Our long-term objective is thus to design target-specific antioxidants/metal chelators and better understand their pharmacological mechanisms for AD and other human diseases, based on an emerging "pharmacophore conjugation" concept for drug development. The specific hypothesis for this proposal is that amyloid-targeting antioxidants/metal chelators assume targeted interdictions against cerebral A¿ amyloid pathology and associated oxidative stress. We have synthesized and characterized a novel bifunctional antioxidant- XH2 with chemically conjugated amyloid-binding (benzothiazole) and metal-chelating antioxidant (lipoate) moieties. We base the hypothesis on previous observations and current pilot data suggest that: (i) biometals such as Fe, Cu, Zn, which are strongly present in human amyloid plaques, promote A¿ amyloidosis and oligomerization that are mediated by reactive oxygen species (ROS) such as H2O2 and attenuated by catalase and metal chelators- DTPA and EDTA; (ii) XH2 molecule has only one NH group (<5 hydrogen-bond donors), two N and one O atoms (<10 hydrogen bond acceptors), MW=415 (<500), and the measured octanol/water partition coefficient = 2.1¿0.1 (<5). It agrees well with the general Lipinski's Rule of Five; (iii) XH2 interacts with A¿1-40 peptide computationally and has an affinity binding constant of KD=4.43 ¿M toward monomeric A¿1-40 peptide molecules in its freshly prepared solution; (iv) XH2 has no neurotoxicity at low micromolar concentrations, and it attenuates cerebral A¿ amyloid pathology in PS1/APP doubly transgenic mice without inducing apparent animal toxicity and behavior disturbances. We plan to test our current hypothesis and to achieve the objective of this application by pursuing the following three specific aims: 1. Determine the effects of XH2 upon A¿ neurotoxicity and APP translation in cell culture; 2. Determine XH2 binding constants for aggregated and mixed A¿1-40/42 peptides and blood-brain barrier (BBB) penetration of XH2; 3. Determine the effects of XH2 upon cerebral A¿ amyloid pathology, protein glutathionylation, and biometal profiles in amyloid plaques from PS1/APP transgenic mice. To achieve these specific aims, an array of experimental techniques such as surface plasmon resonance (SPR), LC/MS, SDS-PAGE, ELISA, semi-quantitative immunohistochemistry, laser capture microdissection (LCM) coupled with x-ray fluorescence microscopy (micro-XRM) techniques, and in vitro (human SH-SY5Y neuroblastoma and E17 primary rat cortical cells) and in vivo (PS1/APP doubly transgenic mouse) AD models, will be employed for the proposed studies. The overall rationale for the proposal is: our understanding about the molecular mechanism(s) and therapeutic values of amyloid-targeted antioxidants/chelators as potential AD-modifying agents need to be further clarified and validated.

描述(申请人提供)：目前抗氧化剂/金属螯合疗法治疗阿尔茨海默病(AD)的临床益处有限，因为它们的疾病靶标特异性较差。阿尔茨海默病(AD)是最常见的老年痴呆症。此外，抗氧化剂/金属螯合作用在AD淀粉样蛋白病理中的确切作用机制(S)尚不清楚。因此，我们的长期目标是设计靶向特定的抗氧化剂/金属螯合剂，并更好地了解它们对AD和其他人类疾病的药理作用机制，基于一种新兴的药物开发的“药效团结合”概念。这一提议的具体假设是，以淀粉样蛋白为靶标的抗氧化剂/金属螯合剂假定有针对性地阻断大脑淀粉样蛋白病理和相关的氧化应激。我们合成并表征了一种新型的双功能抗氧剂--XH2，它含有化学结合的淀粉样蛋白(苯并噻唑)和金属螯合抗氧化剂(脂酸盐)。我们基于先前的观察和目前的初步数据表明：(I)生物金属，如铁，铜，锌，强烈存在于人类淀粉样斑块中，促进Aβ淀粉样变性和寡聚化，由过氧化氢等活性氧物种(ROS)介导，并被过氧化氢酶和金属螯合剂DTPA和EDTA减弱；(Ii)XH2分子只有一个NH基团(&lt；5个氢键供体)，两个N和一个O原子(&lt；10个氢键受体)，MW=415(&lt；500)，测得的辛醇/水分配系数=2.1±0.1(？lt；5)。它很好地符合一般的Lipinski规则5；(Iii)XH2与A？1-40肽通过计算相互作用，在其新制备的溶液中对单体A？1-40肽分子的亲和力结合常数为Kd=4.43？M；(Iv)XH2在低微摩尔浓度下没有神经毒性，它可以减轻PS1/APP双转基因小鼠的脑淀粉样蛋白病理，而不会引起明显的动物毒性和行为障碍。我们计划验证我们目前的假设，并通过追求以下三个特定目标来实现这一应用的目标：1.确定XH2对细胞培养中Aβ的神经毒性和APP翻译的影响；2.测定聚集和混合A？1-40/42肽的XH2结合常数和XH2对血脑屏障(BBB)的穿透；3.确定XH2对PS1/APP转基因小鼠脑淀粉样蛋白病理、蛋白质谷胱甘肽基化和生物金属谱的影响。为了实现这些特定的目标，将采用一系列实验技术，如表面等离子共振(SPR)、LC/MS、SDS-PAGE、ELISA法、半定量免疫组织化学、激光捕获显微解剖(LCM)结合X射线荧光显微镜(MICRO-XRM)技术、体外(人SH-SY5Y神经母细胞瘤和E17原代大鼠皮质细胞)和体内(PS1/APP双转基因小鼠)AD模型。这项提议的总体理由是：我们对淀粉样蛋白靶向抗氧化剂/螯合剂作为潜在的AD修饰剂的分子机制(S)和治疗价值的理解需要进一步澄清和验证。