Characterization of Naphthalene DNA Adducts in Mice and Firefighters

小鼠和消防员中萘 DNA 加合物的表征

• 批准号: 10707915
• 负责人: Sarrah Hannon
• 金额: $ 4.77万
• 依托单位: UNIVERSITY OF ARIZONA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10707915
• 关键词: Academia; Adult; Aromatic Polycyclic Hydrocarbons; Aryl Hydrocarbon Hydroxylases; Benzo(a)pyrene; Biological Assay; Blood; Blood specimen; C57BL/6 Mouse; Carcinogens; Career Mobility; Cells; Classification; Collaborations; Cytochrome P450; DNA; DNA Adduction; DNA Adducts; DNA Maintenance; Data; Detection; Development; Environment; Environmental Pollutants; Enzymes; Epoxy Compounds; Exposure to; Fellowship; Female; Fire - disasters; Fossil Fuels; Foundations; Future; General Population; Generations; Genes; Human; In Vitro; Incidence; Inhalation; Inhalation Exposure; International Agency for Research on Cancer; Knowledge; Leukocytes; Literature; Liver; Liver Microsomes; Lung; Malignant Neoplasms; Mass Spectrum Analysis; Metabolic Pathway; Metabolism; Methods; Microsomal Epoxide Hydrolase; Mus; Mutagenesis; NMR Spectroscopy; Naphthalene; Naphthoquinones; Nasal Epithelium; Neuroblastoma; Occupational Groups; Occupations; Oxidoreductase; Pathogenesis; Predictive Value; Public Health; Publishing; Quinones; Rattus; Research; Research Personnel; Risk; Risk Assessment; Site; Smoke; Source; Structure of parenchyma of lung; Testing; Time; Tissues; Tobacco; Toxicokinetics; Training; Transgenic Mice; Urine; Wild Type Mouse; Work; adduct; adenoma; cancer risk; cancer type; carcinogenesis; carcinogenicity; combustion product; cytotoxic; exposed human population; fire fighter; genetic manipulation; genotoxicity; in vivo; lung carcinogenesis; male; mouse model; professional atmosphere; sex; skills; tumor

Project Summary/Abstract Naphthalene (NA), a simple polycyclic aromatic hydrocarbon, is persistently present in the environment as a byproduct of combustion of fossil fuels and burning of tobacco and other products. Its ubiquitous presence results in widespread exposure to the general population. Certain occupational groups, such as firefighters, have elevated levels of exposure. Firefighters also have increased incidences of certain types of cancer. NA is currently classified by the International Agency for Research on Cancer (IARC) as a Class 2B Carcinogen. There is direct evidence of tumor formation in mice and rats but no direct evidence of carcinogenecity of NA in humans at this time. The pathogenesis of tumor formation in mice and rats after exposure to NA is unclear; cytotoxic and genotoxic mechanisms are both proposed in the current literature. NA metabolism results in the generation of reactive intermediates such as 1,2-epoxide and reactive metabolites such as 1,4- and 1,2- naphthoquinone (NAQ). Reactive quinone and epoxide metabolites of similar compounds, such as benzo[a]pyrene, have been shown to enact their carcinogenecity through DNA adduct formation. Published ex vivo and in vitro data have demonstrated that NA metabolites can form adducts with DNA. The objective of this study is to identify and quantify NA-DNA adducts in mouse lung as well as mouse and human blood to enable assessment of potential genotoxicity in firefighters. Several hypotheses will be tested: 1) Circulating reactive NA metabolites, particularly NAQs, will form stable as well as depurinating adducts with DNA in both lung tissue and blood leukocytes in vivo; 2) the types and abundances of NA-DNA adducts in circulating leukocytes will at least partly reflect adduct formation in the lung; 3) the types of NA-DNA adducts detected in circulating leukocytes from exposed mice and firefighters will be similar; and 4) exposure to fire smoke will increase NA- DNA adduct levels in firefighters. These hypotheses will be tested through the application of 3 Specific Aims. In Aim 1, I will Identify and quantitate NA-DNA adducts formed in wild-type (WT) mice following NA inhalation exposure, with use of mass spectrometry methods. In Aim 2, I will dissect metabolic pathways responsible for NA-DNA adduct formation in the lung and circulating leukocytes of NA-exposed mice, with use of unique transgenic mouse models (liver-Cpr-null, liver-Ephx1-null, and Cyp2abfgs-null). In Aim 3, I will characterize NA-DNA adducts in blood specimens from firefighters and control donors. This project will provide direct evidence for the formation of NA-DNA adducts in vivo, lay the foundation for future studies of the genotoxicity of NA, obtain evidence to support more extensive assessments of the carcinogenic risks of NA to firefighters, and could have direct implications for the general population. Through the execution of this project and the help of this fellowship, I will be fully trained in scientific and professional skills necessary for my career advancement as an independent researcher in academia.

项目摘要/摘要 萘（Na）是一种简单的多环芳烃，在环境中持续存在作为一个 化石燃料燃烧的副产品以及烟草和其他产品的燃烧。它无处不在的存在 导致广泛暴露于普通人群。某些职业群体，例如消防员 暴露水平升高。消防员还增加了某些类型的癌症的发病率。 na是 目前由国际癌症研究机构（IARC）归类为2B类致癌。 在小鼠和大鼠中有直接的肿瘤形成的证据，但没有直接证据表明Na的癌性 这个时候人类。暴露于NA后，小鼠和大鼠肿瘤形成的发病机理尚不清楚。 当前文献中都提出了细胞毒性和遗传毒性机制。 NA代谢导致 产生反应性中间体，例如1,2-环氧化物和反应性代谢物，例如1,4-和1,2-- 萘醌（NAQ）。相似化合物的反应性醌和环氧代谢物，例如 苯并[a] pyrene已被证明可以通过DNA加合物形成实现其癌性。出版物 体内和体外数据表明，Na代谢物可以与DNA形成加合物。这个目的 研究是为了识别和量化小鼠肺以及小鼠和人血中的Na-DNA加合物以实现 评估消防员中潜在的遗传毒性。将测试几个假设：1）循环反应性 Na代谢产物，尤其是NAQ，将形成稳定的以及在两个肺中用DNA降低加合物 体内组织和血液白细胞； 2）循环白细胞中Na-DNA加合物的类型和丰度 将至少部分反映肺中的加合物形成； 3）在循环中检测到的Na-DNA加合物的类型 裸露的小鼠和消防员的白细胞将相似。 4）暴露于火烟会增加NA- 消防员的DNA加合物水平。这些假设将通过应用3个特定目的来检验。在 AIM 1，我将识别并定量Na吸入后在野生型（WT）小鼠中形成的Na-DNA加合物 暴露，使用质谱法。在AIM 2中，我将剖析负责的代谢途径 肺中的Na-DNA加合物形成和暴露于NA的小鼠的循环白细胞，并使用独特 转基因小鼠模型（肝脏-CPR-NULL，LIVER-EPHX1-NULL和CYP2ABFGS-NULL）。在AIM 3中，我会描述 来自消防员和控制供体的血液标本中的NA-DNA加合物。该项目将提供直接 在体内形成Na-DNA加合物的证据，为未来研究遗传毒性奠定了基础 NA，获得证据，以支持NA对消防员的致癌风险进行更广泛的评估， 并可能对普通人群有直接的影响。通过执行该项目和 这项奖学金的帮助，我将接受我职业所需的科学和专业技能的全面培训 作为学术界的独立研究员的进步。