Nanoprobes for imaging RONS and drug-induced hepatotoxicity

描述(由申请人提供)：从缺血/再灌流或无菌损伤，到急性和慢性细菌感染，再到癌症、心血管疾病和关节炎等慢性疾病，活性氧和氮物种(RON)的生成增加是许多病理过程的标志。能够确定RON在何时何地作为病理化学信使产生，对于了解这些疾病的病因和优化针对这些潜在威胁生命的疾病的治疗干预至关重要。由于其短的半衰期，RON的产生发生在局部的病理学上，通常发生在疾病发病的亚临床时间点。体内RONS水平的早期和实时分子成像将影响广泛的疾病状态。RONS的产生也与药物代谢密切相关。在新陈代谢过程中，高活性的代谢物往往与肝毒性有关。虽然每种药物的反应代谢物在其化学结构上是独一无二的，但代谢物诱导的肝毒性的潜在机制几乎对候选药物和已批准的药物分子都是通用的：氧化和亚硝化应激：产生快速与各种亚细胞成分(如蛋白质、脂肪和DNA)反应的RON，从而导致有害后果。据估计，进入第一阶段临床试验的新药候选药物中，只有10%曾被批准用于人类使用。药物引起的肝毒性是美国FDA批准的药物撤回的最常见原因，这些药物占美国急性肝功能衰竭病例的50%以上。本研究建议开发一种体内RONS成像平台技术，并在小鼠模型上验证其在药物诱导的RONS肝毒性成像中的应用。传感器平台基于共轭聚合物纳米颗粒，已被证明具有良好的光学性能和生物兼容性。将设计、制备和验证一系列纳米探针，用于对体内产生的特定核仁进行成像。具体地说，有三个目标：1)设计生物相容的基于FRET的荧光纳米管，用于体内RONS的成像；2)开发基于CRET的化学发光探针，用于体内RONS的成像。3)药物诱导的小鼠肝脏RONS的实时在体监测。这些RONS纳米探针将对我们对疾病病理和检测的理解产生重大影响，并提供以前无法获得的有关肝毒性倾向的信息，并有助于及早选择有前途的候选药物进入临床试验。

DESCRIPTION (provided by applicant): The elevated generation of reactive oxygen and nitrogen species (RONS) is a hallmark of many pathological processes ranging from ischemia/reperfusion or sterile injury, to acute and chronic bacterial infections, to chronic diseases such as cancer, cardiovascular disease, and arthritis. The ability to determine when and where RONS are being generated as pathological chemical messengers is critical to both understanding the etiology of these diseases and optimizing therapeutic interventions against these potentially life-threatening conditions. Due to their short half-lives, the generation of RONS occurs locally to pathology and often at subclinical time points in the pathogenesis of disease. Early and real-time molecular imaging of RONS levels in vivo will impact a wide array of diseased states. RONS generation also highly involves with drug metabolism. Upon metabolism, highly reactive metabolites are often associated with hepatotoxicity. While the reactive metabolite profile of each drug is unique to its chemical structure, an underlying mechanism of metabolite-induced hepatotoxicity nearly universal to both drug candidates and approved drug molecules is oxidative and nitrosative stress: the generation of RONS that react rapidly with a variety of subcellular components (e.g. protein, lipid, and DNA) with deleterious outcomes. It is estimated that of new drug candidates entering Phase I clinical trial, only 10% are ever approved for human use. Drug-induced hepatotoxicity is the most common reason for withdrawal of US FDA-approved drugs, which account for more than 50% of acute liver failure cases in the US. This research proposes to develop a platform technology for in vivo imaging RONS, and validate its application for imaging drug-induced RONS hepatotoxicity in a mouse model. The sensor platform is based on conjugated polymer nanoparticles that have been shown with excellent optical properties and biocompatibilities. A series of nanoprobes will be designed, prepared and validated for imaging specific RONS generated in vivo. Specifically, there are three Aims: 1) Design of biocompatible FRET-based fluorescent nanoparobes for in vivo imaging of RONS; 2) Development of CRET-based chemiluminescent probes for in vivo imaging of RONS. 3) Real-time in vivo monitoring of drug-induced RONS in mouse liver. These RONS nanoprobes will significantly impact on our understanding of disease pathology and detection, and provide previously unattainable information regarding the propensity for hepatotoxicity and aid the early selection of promising drug candidates to enter into clinical tria.