Human liver-kidney model elucidates the mechanisms of aristolochic acid nephrotoxicity
Human liver-kidney model elucidates the mechanisms of aristolochic acid nephrotoxicity
复制标题
DOI：
10.1172/jci.insight.95978
复制
发表时间：
2017-11-16
期刊：
影响因子：
8
通讯作者：
Eaton, David L.
中科院分区：
文献类型：
--
作者：
Chang, Shih-Yu;Weber, Elijah J.;Eaton, David L.
环境暴露对人类健康构成重大威胁。然而，由于伦理问题，通常很难研究人类受试者的毒理学机制。植物来源的马兜铃酸是迄今为止发现的最有效的肾毒素和致癌物之一，但其在人类中的生物活化机制仍知之甚少。微生理系统（器官芯片）提供了一种方法来检查复杂的，物种特异性的毒理学效应的药物和环境化学品使用人体细胞。我们用微流体连接了芯片上的肾脏和芯片上的肝脏，以确定马兜铃酸I（一种已知的肾毒素和人类致癌物）的生物激活和转运机制。我们证明，人肝细胞特异性代谢AA-I大大增加了其对人肾近端小管上皮细胞的细胞毒性，包括马兜铃内酰胺加合物的形成和肾损伤生物标志物的释放。AA-I的肝脏生物转化为肾毒性代谢物涉及硝基还原，然后是硫酸盐偶联。在这里，我们发现，在人体组织系统中，肝脏nqo1生成的马兜铃内酰胺产物（al - i - noso3）的硫酸盐缀合物是AA-I的肾毒性形式。这种缀合物可以通过MRP膜转运体从肝脏转运，然后通过一个或多个有机阴离子膜转运体主动转运到肾脏组织。这种集成的微生理系统为研究器官-器官相互作用提供了一种离体方法，即一个组织对药物或其他异种生物的代谢可能影响其对另一个组织的毒性，并且代表了研究与环境和其他毒性暴露相关的化学毒性的实验方法。
Environmental exposures pose a significant threat to human health. However, it is often difficult to study toxicological mechanisms in human subjects due to ethical concerns. Plant-derived aristolochic acids are among the most potent nephrotoxins and carcinogens discovered to date, yet the mechanism of bioactivation in humans remains poorly understood. Microphysiological systems (organs-on-chips) provide an approach to examining the complex, species-specific toxicological effects of pharmaceutical and environmental chemicals using human cells. We microfluidically linked a kidney-on-a-chip with a liver-on-a-chip to determine the mechanisms of bioactivation and transport of aristolochic acid I (AA-I), an established nephrotoxin and human carcinogen. We demonstrate that human hepatocyte-specific metabolism of AA-I substantially increases its cytotoxicity toward human kidney proximal tubular epithelial cells, including formation of aristolactam adducts and release of kidney injury biomarkers. Hepatic biotransformation of AA-I to a nephrotoxic metabolite involves nitroreduction, followed by sulfate conjugation. Here, we identify, in a human tissue-based system, that the sulfate conjugate of the hepatic NQO1-generated aristolactam product of AA-I (AL-I-NOSO 3) is the nephrotoxic form of AA-I. This conjugate can be transported out of liver via MRP membrane transporters and then actively transported into kidney tissue via one or more organic anionic membrane transporters. This integrated microphysiological system provides an ex vivo approach for investigating organ-organ interactions, whereby the metabolism of a drug or other xenobiotic by one tissue may influence its toxicity toward another, and represents an experimental approach for studying chemical toxicity related to environmental and other toxic exposures.