Elucidating Metabolic and Physicochemical Mechanisms of PAH Susceptibility in Toxicity Test Systems and Humans

项目概要- TEEGUARDEN PROJECT 长期以来，缺乏对毒性测试系统敏感性的分子基础的理解是一个长期的问题。 阻碍改进风险评估、改进SRP场地的清理决策和成功的健康 缓解措施。我们的目标是开发变革性的，基于活性的蛋白质组探针和多模式的 化学显微镜测量代谢和分布过程，有助于差异 对多环芳烃暴露的易感性。我们假设组织中可测量但通常被忽视的差异 分布和代谢能力，激活和/或解毒多环芳烃有助于不同的敏感性。 为了验证我们的假设，我们将完成三个目标：1。鉴定活性P450、谷胱甘肽-S- 转移酶和UDP-葡萄糖醛酸转移酶代谢多环芳烃和多环芳烃代谢物。我们将 在组织样本中孵育基于活性的探针，以使用我们的蛋白质组学富集和鉴定活性酶 平台2.开发一种单一的测定方法，通过以下方式确定PAH代谢率和代谢易感性： 将PAH代谢率与酶活性的总体测量相关联。我们将孵化基于活动的探针， 组织，同时进行标准PAH代谢试验，以确定底物特异性和代谢 活性酶的常数。3.确定测试系统和人体的暴露敏感性 取决于PAH的物理化学性质、组织组成和身体组成。我们将测量 我们系统中的组织成分，并测量和预测这些系统中多环芳烃的分布， 还有人类我们研究的产品直接增强了每个项目和核心的相关性和影响力 为利益相关者。我们的创新（ABPP和多模态化学显微镜）将开启新的科学 在理解差异磁化率的两个关键分子决定因素方面的视野。这项工作将 通过a）证明“危险物质、其剂量、暴露 途径和模式生物被认为是在时间，流行和检测的背景下， 接触”，并通过B）确保“工作是在其与人类接触的相关性方面的背景。” 我们的研究结果将直接为超级基金场地的多环芳烃人类健康评估提供信息和改进。

PROJECT SUMMARY – TEEGUARDEN PROJECT Lack of understanding the molecular basis for susceptibility across toxicity test systems is a long-standing barrier to improved risk assessment, improved cleanup decisions for SRP sites, and successful health mitigations. Our objective is to develop transformative, activity-based proteomic probes and multi-modal chemical microscopy to measure the metabolic and distributional processes that contribute to differential susceptibility to PAH exposure. We hypothesize that measurable but commonly ignored differences in tissue distribution and metabolic capacity to activate and/or detoxify PAHs contributes to differential susceptibility. To test our hypothesis, we will complete three aims: 1. Identify the complete set of active P450, glutathione-S- transferase and UDP-glucuronosyltransferase enzymes that metabolize PAHs & PAH metabolites. We will incubate activity-based probes in tissue samples to enrich and identify active enzymes using our proteomics platform. 2. Develop a single assay to determine both PAH metabolic rates and metabolic susceptibility by relating PAH metabolic rates to global measures of enzyme activity. We will incubate activity-based probes in tissues while conducting standard PAH metabolism assays to determine substrate specificity and metabolic constants for active enzymes. 3. Determine how exposure susceptibility across test systems and humans depends upon PAH physicochemical properties, tissue composition, and body composition. We will measure tissue composition across our systems and measure and predict the disposition of PAHs across these systems, and humans. The products of our research directly enhance the relevance and impact of each project and core for stakeholders. Our innovations (ABPP and multi-modal chemical microscopy) will open new scientific horizons in the understanding of two key molecular determinants of differential susceptibility. The work will satisfy explicit expectations for SRP by a) demonstrating “that the hazardous substance, its dose, exposure pathway and model organisms are considered within the context of timing, prevalence, and detection of exposure” and by b) assuring that the “work is contextualized in terms of its relevance to human exposure.” Our research results will directly inform and improve human health assessment for PAHs at Superfund sites.