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: 10462039
• 负责人: Sarrah Hannon
• 金额: $ 4.68万
• 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/10462039
• 关键词: Academia; Adult; Aromatic Polycyclic Hydrocarbons; Aryl Hydrocarbon Hydroxylases; Benzo(a)pyrene; Biological Assay; Blood; Blood specimen; Carcinogens; Career Mobility; Cells; Collaborations; Cytochrome P450; DNA; DNA Adduction; DNA Adducts; Data; Detection; Development; Environment; Environmental Pollution; 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; Lead; Leukocytes; Literature; Liver; 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; 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.

项目概要/摘要 萘 (NA) 是一种简单的多环芳烃，作为一种化学物质持续存在于环境中。 化石燃料燃烧以及烟草和其他产品燃烧的副产品。它的存在无处不在 导致一般人群广泛接触。某些职业群体，例如消防员， 暴露水平较高。消防员患某些类型癌症的发病率也有所增加。 NA 是 目前被国际癌症研究机构 (IARC) 列为 2B 类致癌物。 有直接证据表明小鼠和大鼠中存在肿瘤形成，但没有直接证据表明 NA 在小鼠和大鼠中具有致癌性。 此时的人类。小鼠和大鼠接触 NA 后肿瘤形成的发病机制尚不清楚； 当前文献中均提出了细胞毒性和基因毒性机制。 NA 代谢导致 生成反应性中间体（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）。类似化合物的反应性醌和环氧化物代谢物，例如 苯并[a]芘已被证明可通过 DNA 加合物形成发挥致癌作用。发布前 体内和体外数据表明NA代谢物可以与DNA形成加合物。此举的目的 该研究旨在鉴定和量化小鼠肺以及小鼠和人类血液中的 NA-DNA 加合物，以便能够 评估消防员的潜在遗传毒性。将测试几个假设：1）循环反应性 NA 代谢物，特别是 NAQ，将与双肺中的 DNA 形成稳定的脱嘌呤加合物 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 至少部分反映肺部加合物的形成； 3）循环中检测到的NA-DNA加合物的类型 暴露的小鼠和消防员的白细胞会相似； 4) 暴露于火烟雾中会增加 NA- 消防员的 DNA 加合物水平。这些假设将通过 3 个具体目标的应用进行检验。在 目标 1，我将鉴定并定量野生型 (WT) 小鼠吸入 NA 后形成的 NA-DNA 加合物 暴露，使用质谱方法。在目标 2 中，我将剖析负责的代谢途径 使用独特的方法，在 NA 暴露小鼠的肺和循环白细胞中形成 NA-DNA 加合物 转基因小鼠模型（肝 Cpr 无效、肝 Ephx1 无效和 Cyp2abfgs 无效）。在目标 3 中，我将描述 消防员和对照献血者血液样本中的 NA-DNA 加合物。该项目将直接提供 体内形成NA-DNA加合物的证据，为未来的遗传毒性研究奠定基础 NA，获取证据支持对消防员的 NA 致癌风险进行更广泛的评估， 并可能对普通民众产生直接影响。通过本项目的实施和 在这项奖学金的帮助下，我将得到职业生涯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取得进步。