CKDu and Ochratoxin-A: risk assessment studies in a microphysiological system

项目摘要/摘要 CKDu(病因不明的CKD)主要发生在发展中国家，与生活和 在炎热气候的农业社区工作。CKDU的治疗费用在低收入人群中是负担不起的 在一些国家，30天的基本药物可能需要高达18天的工资。一个建议的风险因素是 慢性接触赭曲霉毒素A(OTA)是一种常见的真菌毒素，存在于干燥的谷物、豆类中 水果、葡萄酒、咖啡和茶。然而，在一些动物物种中，太田油是一种已证实的肾癌物质。 由于缺乏包括肝脏在内的适当模型，人类的危险识别一直难以捉摸。 生物活化是最终有毒物质的来源。 我们最近开发了一种耦合的肝和肾微生理系统(MPS)，用于识别 转运蛋白特定的肝酶、肾脏转运蛋白和与之相关的中间化学代谢产物 马兜铃酸介导的CKDu。恒流培养，原代肝、肾细胞显示 局部化的I/II相酶和转运蛋白，这是对永生化细胞系的重大进步， 失去酶的表达和转运蛋白的极化。此外，原代肾近端小管细胞显示 肾脏损伤生物标志物的强健和仿生分泌。 对于这项提议，我们开发了一种创新的一体化肝肾MPS，它结合了 单个芯片上的耦合和非耦合肾脏MPS。我们建议定义剂量-反应关系 赭曲霉毒素A与热应激性肾病--鉴定参与肾脏赭曲霉毒素的转运蛋白 A摄取和外排，并确定首过代谢在赭曲霉毒素A诱导的肾病中的作用。一个 更好地了解OTA引起的肾脏损伤的机制将支持风险评估的变化， 监管机构关于允许接触水平的政策，以及高危人群遗传风险因素的确定 人口。

Project Summary/Abstract CKDu (CKD of unknown etiology) occurs primarily in the developing world, and is associated with living and working in agricultural communities in hot climates. The cost of treating CKDu is unattainable in low-income countries, where 30 days of essential medications can cost up to 18 days wages. One proposed risk factor of CKDu is chronic exposure to Ochratoxin A (OTA), a common mycotoxin found in cereal grains, beans, dried fruits, wine, coffee, and tea. OTA is a demonstrated renal carcinogen in several animal species, however hazard identification in humans has been elusive due to the lack of adequate models that include hepatic bioactivation as a source of the ultimate toxic moiety. We have recently developed a coupled liver>kidney microphysiologic system (MPS) that was used to identify the specific hepatic enzymes, renal transporters, and intermediate chemical metabolites associated with aristolochic acid mediated CKDu. Cultured under constant flow, primary liver and kidney cells demonstrated localized phase-I/II enzymes and transporters, a significant advance over immortalized cell lines that rapidly lose enzyme expression and transporter polarization. In addition, primary kidney proximal tubule cells exhibited robust and biomimetic secretion of biomarkers of kidney injury. For this proposal, we have developed an innovative integrated liver>kidney MPS that incorporates both a coupled and uncoupled kidney MPS on a single chip. We propose to define the dose-response relationships of ochratoxin A and heat stress-induced nephropathy, identify the transport proteins involved in renal ochratoxin A uptake and efflux, and determine the role of first pass metabolism in ochratoxin A-induced nephropathy. A better understanding of the mechanisms of OTA-induced kidney injury will support changes in risk assessment, regulatory agency policies on allowable exposure levels, and determination of genetic risk factors in high-risk populations.