R21: Acidic Nanoparticles for Restoration of Autophagy in Age-associated NAFLD

R21：酸性纳米颗粒用于恢复年龄相关性 NAFLD 中的自噬

基本信息

批准号：
9902306
负责人：
MARK W. GRINSTAFF
金额：
$ 20.06万
依托单位：
BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2022-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9902306
关键词：
Acidity Acids Action Research Address Age Autophagocytosis Autophagosome Biological Assay Biology Biomedical Engineering Butylene Glycols Cell physiology Cells Cellular Metabolic Process Chronic Collaborations Data Development Diabetes Mellitus Disease Disease model Drug Metabolic Detoxication Elderly Ensure Environment Evaluation Experimental Designs Exposure to Failure Fatty Acids Functional disorder Future Glycolates HepG2 Hepatic Hepatocyte Impairment In Vitro Kinetics Lactic acid Length Libraries Light Lipids Liver Lysosomes Metabolic Modeling Molecular Nanotechnology Normal Range Obesity Organelles Palmitates Pharmacology Polyesters Polymer Chemistry Polymers Process Proteins Quality Control Regulation Risk Factors Role Safety Scientist Stimulus Structure Structure of beta Cell of islet Succinic Acids System Technology base efficacy study ethylene glycol experimental study improved improved functioning in vivo insulin secretion insulinoma middle age mouse model nanoparticle non-alcoholic fatty liver disease novel novel therapeutics pharmacokinetics and pharmacodynamics restoration screening spatiotemporal tool

项目摘要

ABSTRACT This exploratory R21 proposal describes two novel nanotechnologies for acidification of the lysosome and for restoration of autophagic flux. Autophagy, the intracellular process by which proteins and organelles are degraded, requires an acidic lysosome. Failure to acidify the lysosomal compartment affords accumulation of autophagosomes, lipids, and associated undigested content. Impaired lysosomal acidification and reduced autophagic flux are central to non-alcoholic fatty liver disease (NAFLD). NAFLD occurs primarily among the middle-aged and the elderly given that the risk factors for its development increase with advancing age. Current pharmacological and molecular tools are able to reduce lysosomal acidity (increase pH); however, no tools exist to increase lysosomal acidity (decrease pH). Key to our advance is the use of lysosomal accumulating nanoparticles (NPs) that release acid to lower the local pH. Specifically, we propose two new NP technologies to increase lysosomal acidity. The first is a stimuli-responsive NP that acidifies its local environment upon exposure to light (i.e., light activated acid nanoparticle, light-acNP). The second NP responds to the pH of a dysfunctional lysosome (5.7 - 6) to release acid further lowering the pH to a healthy/normal value (4 - 5). These pH-activated acid nanoparticles (pH-acNPs) are polyester-based NPs composed of a potent diacid, tetrafluorosuccinic acid (TFSA), to further lower the pH upon NP degradation. We hypothesize that upon accumulation in lysosomes, the acNPs will release acid through light activation or pH-activation and thereby restore lysosomal acidity and autophagic flux quickly. Further, we hypothesize that the extent of restoration will depend on the length of light exposure and the amount of TFSA in the polymer, respectively. Importantly, substantial preliminary data support the proposed studies, well-characterized materials and rigorous experimental designs are established, and essential cross-disciplinary collaborations and expertise (nanotechnology, polymer chemistry, cell metabolism, and autophagy) are in place to address these hypotheses. The specific aims of this two-year proposal are: Aim 1. Evaluate lysosome-targeted acNPs that activate with light (light-acNPs); and, Aim 2. Synthesize and evaluate lysosome-targeted acNPs that activate at pH 6 (pH-acNPs). Successful completion of the proposal will provide two new tools for scientists, clinicians, and biomedical engineers to study autophagy biology to facilitate agent screening and mechanism(s) of action. From a nanotechnology perspective, new nanoparticle compositions and functions will be identified as well as a means to control a key cellular process via a nanoparticle. Finally, these results would support further evaluation of the acNPs in in vivo murine models to include safety, PK/PD, and efficacy studies as part of a future R01 proposal focused on NAFLD.

抽象的这个探索性的 R21 提案描述了两种用于溶酶体酸化和自噬通量的恢复。自噬，蛋白质和细胞器的细胞内过程降解，需要酸性溶酶体。未能酸化溶酶体室会导致自噬体、脂质和相关的未消化内容。溶酶体酸化受损并减少自噬通量是非酒精性脂肪肝病 (NAFLD) 的核心。 NAFLD 主要发生在中老年人，随着年龄的增长，其发生的危险因素也会增加。当前的药理学和分子工具能够降低溶酶体酸度（增加 pH 值）；然而，没有存在增加溶酶体酸度（降低 pH）的工具。我们进步的关键是溶酶体的使用积累释放酸以降低局部 pH 值的纳米颗粒 (NP)。具体来说，我们提出了两个新的 NP 增加溶酶体酸度的技术。第一个是刺激响应 NP，可酸化其局部环境暴露于光后（即光活化酸纳米颗粒，light-acNP）。第二个 NP 对 pH 值做出响应功能失调的溶酶体 (5.7 - 6) 释放酸，进一步将 pH 值降低至健康/正常值 (4 - 5)。这些 pH 激活酸纳米颗粒 (pH-acNP) 是由强效二酸组成的聚酯基纳米颗粒，四氟琥珀酸 (TFSA)，进一步降低 NP 降解时的 pH 值。我们假设 acNP 在溶酶体中积累后，会通过光激活或 pH 激活释放酸，从而快速恢复溶酶体酸度和自噬通量。此外，我们假设程度修复效果取决于曝光时间和聚合物中 TFSA 的含量，分别。重要的是，大量的初步数据支持了拟议的研究，且特征明确材料和严格的实验设计已经建立，并且必要的跨学科合作和专业知识（纳米技术、高分子化学、细胞代谢和自噬）已到位来解决这些问题假设。这项为期两年的提案的具体目标是：目标 1. 评估靶向溶酶体的 acNP 用光激活（light-acNPs）；目标 2. 合成并评估以溶酶体为靶点的 acNP，其在 pH 6（pH-acNP）。该提案的成功完成将为科学家、临床医生和医生提供两种新工具生物医学工程师研究自噬生物学，以促进药物筛选和作用机制。从从纳米技术的角度来看，将确定新的纳米粒子成分和功能以及方法通过纳米颗粒控制关键的细胞过程。最后，这些结果将支持进一步评估体内鼠模型中的 acNP 将包括安全性、PK/PD 和功效研究，作为未来 R01 提案的一部分专注于 NAFLD。