CADMIUM, ZINC, METALLOTHIONEIN AND KIDNEY CYTOTOXICITY

镉、锌、金属硫蛋白和肾细胞毒性

• 批准号: 3251850
• 负责人: DAVID Harold PETERING
• 金额: $ 17.65万
• 依托单位: UNIVERSITY OF WISCONSIN MILWAUKEE
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1990-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3251850
• 关键词: biological models; cadmium; chemical binding; chemical structure function; chemical substitution; cytotoxicity; gel filtration chromatography; high performance liquid chromatography; laboratory mouse; laboratory rabbit; laboratory rat; metal metabolism; metal poisoning; metallothionein; nuclear magnetic resonance spectroscopy; radiotracer; renal cortex; renal toxin; spectrometry; tissue /cell culture; toxicant interaction; zinc

This proposal sets forth integrated physiochemical and biological studies to elucidate biologically relevant structure-function relationships of the metal binding protein, Metallothionein (Mt). This protein is a normal constituent of mammalian tissues. It is also the one well defined site to which the environmentally important, toxic heavy metal Cd binds as it reacts with cells. Years of study have demonstrated that Mt plays a central role in Zn and Cu metabolism and the biochemical toxicology of Cd. However, the nature of its biological functions and, indeed, chemical properties are ill defined. The overall goal of the proposed research is to understand the metal-ligand chemistry of Mt, its biological functions in Zn and Cd metabolism and how these are interrelated. The four co-investigators are independent scientists in complementary research area: JDO in multinuclear NMR structure-function studies of metalloproteins, CFS in inorganic and bioinorganic studies of metallo-drugs and proteins, SSB in the culture and examination of transport properties of kidney cortical cells, and DHP in the cellular metabolism of essential and toxic metals and bioinorganic studies of metal complexes and metallo-proteins. The author's broad, overlapping interests undergird this proposal and lead to the following specific aims: (I) To understand in detail the ligand substitution chemistry of Zn- and Cd-Mt involving either small ligands competing for the Mt-bound metal or apometallo-proteins. Once these homogenous metallothioneins are understood, to investigate the properties of mixed metal, Cd, Zn-metallothioneins in ligand substitution chemistry. (II) To use the kidney cortical cell model to study the normal functions of Zn-Mt, possibly involving biological ligand substitution reactions. (III) Finally, to study the interactions of Cd with this system as they relate to Zn-metallothionein function in metal donation reactions and to the binding of Cd to other sites in the cell. Integrated experiments are designed to study side by side the chemistry of Mt which occurs in vitro with that which may be occurring in cells. Chemical studies are predicted on and use the detailed understanding of metallothionein cluster structures provided by 113 Cd NMR. They will center on careful spectrophotometric kinetic studies to understand the mechanism of the ligand substitution reactions of metallothioneins. Kidney cortical cells will be used as a cellular model highly relevant to Cd toxicology. To relate the chemical results to cells, kinetics of distribution of Zn and Cd among cell components and compartments will be carried out using radiotracers to follow pools of metal and protein. Compartments will be carried out in conjunction with assessment of effects of Cd on cortical cell function.

这项建议阐述了综合的物理化学和生物 阐明生物相关结构与功能的研究 金属结合蛋白与金属硫蛋白(MT)的关系。 这种蛋白质是哺乳动物组织的正常成分。它是 也是一个定义明确的地点，环境 重要的是，有毒的重金属镉在与细胞反应时会结合在一起。 多年来的研究表明，MT在 锌、铜代谢与镉的生化毒理 然而，它的生物功能的性质，确实， 化学性质定义不清。该计划的总体目标 拟议的研究是为了了解金属-配体化学 金属硫蛋白及其在锌、镉代谢中的生物学作用及其机制 这些都是相互关联的。四名联合调查员是独立的 互补研究领域的科学家：多核领域的JDO 金属蛋白的核磁共振结构与功能研究 金属药物和蛋白质的无机和生物无机研究， SSB在细菌培养和运输特性检测中的应用 肾皮质细胞和DHP在细胞代谢中的作用 必需金属和有毒金属与金属的生物无机研究 络合物和金属蛋白。作者的宽泛、重叠的 利益支撑了这项提议，并导致了以下具体内容 目的：(一)详细了解配体取代化学 锌-和镉-mt涉及两个小配体竞争 MT结合的金属或载脂蛋白。一旦这些同质的 了解金属硫蛋白，以研究其性质 混合金属、镉、锌金属硫蛋白在配体取代中的应用 化学反应。(2)应用肾皮质细胞模型研究 锌-线粒体的正常功能，可能涉及生物配体 取代反应。(三)最后，研究 Cd与锌金属硫蛋白功能的关系 在金属捐献反应和Cd与其他位置的结合中 在牢房里。综合实验的设计是为了通过 除了在体外发生的MT的化学作用外， 可能发生在细胞中。化学研究预计将在和 利用对金属硫蛋白簇的详细了解 结构由113Cd核磁共振提供。他们将以谨慎为中心 用分光光度动力学研究了解其机理 金属硫蛋白的配体取代反应。肾 皮质细胞将被用作高度相关的细胞模型 CD毒理学。为了将化学结果与细胞联系起来，动力学 锌、镉在细胞各组分中的分布及 车厢内将使用放射性示踪剂进行以下操作 金属和蛋白质的水池。车厢将在 结合镉对大脑皮层细胞影响的评估 功能。