Airborne PCBs: Sources, Exposures, Toxicities, Remediation: K.C. Donnelly Externship - Promotion of Translational/Transdisciplinary Efforts in Graduate and Post-Doctoral Research

空气中多氯联苯：来源、暴露、毒性、修复：K.C.

• 批准号: 10579012
• 负责人: Keri C Hornbuckle
• 金额: $ 1.55万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10579012
• 关键词: Address; Adolescence; Adolescent; Air; Area; Astrocytes; Back; Bacteria; Biochemical; Biological; Blood Circulation; Brain; CYP2B6 gene; CYP3A4 gene; Cell Culture Techniques; Cells; Chemicals; Child; Communication; Communities; Complex; Cytochrome P450; Cytochromes; Data; Data Science; Detection; Development; Environment; Environmental Health; Environmental Pollutants; Enzymes; Evaluation; Exposure to; Family; Freezing; Future; Genes; Glucuronides; Glutathione; Goals; Health; Hepatocyte; Home; Human; In Vitro; Individual; Indoor environment; Industrialization; Inhalation; Inhalation Exposure; Intervention; Iowa; Knowledge; Laboratories; Lead; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Metabolic; Metabolic Biotransformation; Metabolic syndrome; Metabolism; Methods; Modeling; Molecular; Mothers; Neuraxis; Neurodevelopmental Impairment; Oxides; Parents; Personal Satisfaction; Persons; Polychlorinated Biphenyls; Population; Postdoctoral Fellow; Production; Program Research Project Grants; Protein Isoforms; Public Health; Quinones; Rattus; Recommendation; Research; Research Activity; Research Personnel; Research Priority; Research Project Grants; Resolution; Risk; Risk Assessment; Risk Factors; Role; Route; Sampling; Schools; Scientist; Site; Soil; Source; Sulfate; Superfund; Testing; Toxic effect; Toxicokinetics; Toxicology; Training; Training Programs; Translating; Translational Research; Universities; Work; Xenobiotics; adduct; base; building materials; career; cohort; community engagement; contaminated sediment; contaminated water; cost effective; design; detection method; dietary; experience; exposed human population; externship; fungus; improved; innovation; lipid metabolism; microbial; neurodevelopment; new technology; novel; novel strategies; overexpression; oxidation; prevent; programs; remediation; skills; superfund chemical; superfund site; tool; translational study

PROJECT DESCRIPTION Due to inadvertent production and exposure to polychlorinated biphenyls (PCBs) from environmental sources, adverse health effects remain a critical public health issue long after the ban of commercial production. Through the proposed research, our goal is to gain knowledge related to P450-mediated metabolism through the KC Donnelly externship in partnership with the National Center for Toxicology Research (NCTR). Xenobiotic processing genes (XPGs), such as cytochrome P450s, are known to be expressed and active in the brain [1-8]. This can then lead to the metabolism of central nervous system (CNS)-active chemicals, leading to alterations in toxicokinetics and toxicodynamics of target cells through systemic circulation [9, 10]. Currently, I am working on examining metabolism of PCBs in rat primary astrocytes. However, it is still uncertain where metabolism of PCBs begins. Specifically, following ISRP Project 1, Aim 2, I will be examining region-specific biotransformation of PCBs and PCB metabolites in the adolescent rat brain in vitro (primary cells in culture) to characterize the following local metabolic conversions: oxidation of parent PCBs to OH-PCBs; conjugation of OH- and diOH-PCBs; deconjugation of OH-PCB sulfates (and glucuronides); and oxidation of diOH-PCBs to reactive quinones and subsequently, glutathione adducts (reviewed in [11-13]). To expand upon this work, the precise human metabolism of lower chlorinated PCBs is still uncertain and needs to be explored.Therefore, my overall objective is to examine the P450 isoform-specific metabolism of lower-chlorinated PCBs in state-of-the- art P450-overexpressing human hepatocytes developed by Dr. Lei Guo's laboratory at the National Center for Toxicology Research (NCTR) [14]. This model will be used to test the hypothesis that lower-chlorinated PCBs discovered by the ISRP in indoor and outdoor air, such as 2,2'5,5'-tetrachlorobiphenyl (PCB52) and 3,3’- dichlorobiphenyl (PCB11), are oxidized with different stereoselectivity by several human P450 isoforms, such as CYP2A6, CYP2B6, and CYP3A4 I will test this hypothesis by (1) determining which human P450 isoform is involved in the metabolism of PCB11 and PCB52 and (2) characterizing the PCB metabolites formed by different P450 isoforms using nontarget-high resolution mass spectrometry (Nt-HRMS). These results will inform future translational studies that assess the role of these P450 isoforms in the brain specific metabolism in human-relevant cell culture models. After treating the P450-overexpressing hepatocytes, both cell pellets and supernatant fractions will be collected to assess levels of metabolites present. Supernatant and cells will be flash frozen. These samples would then be transported back to the University of Iowa, where subsequent quantification of key metabolites would be accomplished with standards provided by the ISRP Synthesis Core [15-19]. The proposed studies will investigate the P450 specific metabolism of PCBs in hepatocytes and are a logical extension of the current ISRP goals to determine enzyme-specific metabolism.

项目描述 由于无意中生产和接触环境来源的多氯联苯 (PCB)， 在禁止商业生产很久之后，对健康的不利影响仍然是一个重要的公共卫生问题。 通过拟议的研究，我们的目标是通过以下方式获得与 P450 介导的代谢相关的知识： 与国家毒理学研究中心 (NCTR) 合作的 KC Donnelly 实习项目。 已知异生物质加工基因 (XPG)，例如细胞色素 P450，在 脑[1-8]。这会导致中枢神经系统（CNS）活性化学物质的代谢，从而导致 通过体循环改变靶细胞的毒代动力学和毒动力学[9, 10]。目前，我 我正在研究大鼠原代星形胶质细胞中 PCB 的代谢。但目前仍不确定 PCB 的新陈代谢开始。具体来说，根据 ISRP 项目 1、目标 2，我将研究特定区域 PCB 和 PCB 代谢物在青春期大鼠脑中的体外生物转化（培养中的原代细胞） 表征以下局部代谢转化：母体 PCB 氧化为 OH-PCB；的共轭 OH-和diOH-PCB； OH-PCB 硫酸盐（和葡萄糖醛酸苷）的解共轭；和 diOH-PCBs 的氧化 反应性醌和随后的谷胱甘肽加合物（在[11-13]中综述）。为了扩展这项工作， 低氯多氯联苯的人体精确代谢仍不确定，需要探索。因此，我的研究 总体目标是检查当前状态下低氯 PCB 的 P450 亚型特异性代谢 art 国家癌症中心郭雷博士实验室开发的P450过表达人肝细胞 毒理学研究（NCTR）[14]。该模型将用于检验低氯 PCB 的假设 ISRP 在室内和室外空气中发现的，例如 2,2'5,5'-四氯联苯 (PCB52) 和 3,3'- 二氯联苯 (PCB11) 被几种人类 P450 异构体以不同的立体选择性氧化，例如 作为 CYP2A6、CYP2B6 和 CYP3A4，我将通过 (1) 确定哪种人类 P450 同工型来检验这一假设 参与 PCB11 和 PCB52 的代谢，以及 (2) 表征由以下物质形成的 PCB 代谢物 使用非目标高分辨率质谱 (Nt-HRMS) 检测不同的 P450 同工型。这些结果将 为未来评估这些 P450 异构体在大脑特定代谢中的作用的转化研究提供信息 在人类相关的细胞培养模型中。处理 P450 过度表达的肝细胞后，两种细胞沉淀 并收集上清液部分以评估存在的代谢物的水平。上清液和细胞将 被闪冻。然后这些样本将被运回爱荷华大学，随后 关键代谢物的量化将通过 ISRP 合成核心提供的标准来完成 [15-19]。拟议的研究将调查肝细胞中 PCB 的 P450 特异性代谢，并且是一项 当前 ISRP 目标的逻辑延伸，以确定酶特异性代谢。