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

• 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
• 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

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 该探索性R21提案描述了两种新型纳米技术，用于酸化溶酶体和用于 恢复自噬通量。自噬，蛋白质和细胞器的细胞内过程 退化，需要酸性溶酶体。未能酸化溶酶体室的积累 自噬体，脂质和相关的未消除含量。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 中年和老年人认为其发展的危险因素随着年龄的增长而增加。当前的 药理和分子工具能够降低溶酶体酸度（增加pH）；但是，不 存在增加溶酶体酸度（减少pH）的工具。我们进步的关键是使用溶酶体 积累纳米颗粒（NP），释放酸以降低局部pH。具体来说，我们提出了两个新的NP 增加溶酶体酸度的技术。首先是刺激反应的NP，它酸化其本地环境 暴露于光线后（即，光活化的酸纳米颗粒，光ACNP）。第二个NP响应 功能障碍的溶酶体（5.7-6）释放酸将pH进一步降低至健康/正常值（4-5）。这些 pH激活的酸纳米颗粒（pH-ACNP）是基于聚酯的NP，由有效的二酮组成， 四氟糖核酸（TFSA），以进一步降低NP降解后的pH值。我们假设这是 在溶酶体中积聚，ACNP将通过光激活或pH激活释放酸，并且 从而快速恢复溶酶体酸度和自噬通量。此外，我们假设该程度 恢复的恢复将取决于光暴露的长度和聚合物中的TFSA量 分别。重要的是，实质性的初步数据支持拟议的研究，良好的研究 建立了材料和严格的实验设计，以及基本的跨学科合作和 专业知识（纳米技术，聚合物化学，细胞代谢和自噬）已适当解决这些问题 假设。该为期两年的提案的具体目的是：目标1。评估以溶酶体为靶向的ACNP 用光激活（轻度ACNP）；以及目标2。合成和评估激活溶酶体靶向的ACNP pH 6（pH-acnps）。该提案的成功完成将为科学家，临床医生和 生物医学工程师研究自噬生物学，以促进剂筛查和作用机制。从 纳米技术的观点，将确定新的纳米颗粒组成和功能以及一种手段 通过纳米颗粒控制关键的细胞过程。最后，这些结果将支持对 作为未来R01提案的一部分，体内鼠模型中的ACNP包括安全性，PK/PD和功效研究 专注于NAFLD。