Novel Zebrafish Models to Study Toxicity of PCBs and Pesticides During Pregnancy

研究怀孕期间多氯联苯和农药毒性的新型斑马鱼模型

• 批准号: 7362510
• 负责人: LISA L SATTERWHITE
• 金额: $ 7.8万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-28 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7362510
• 关键词: Agonist; Agriculture; Area; Aryl Hydrocarbon Receptor; Baltimore; Biological Assay; Birth; Cardiology; Cardiotoxicity; Cardiovascular system; Cell Count; Cell Cycle Arrest; Cell division; Cells; Child; Child health care; Childhood; Chlorpyrifos; Community Workers; Condition; Congenital Abnormality; Congenital Heart Defects; DNA Microarray Chip; DNA Microarray format; Data; Defect; Development; Dioxins; Down-Regulation; Embryo; End Point Assay; Epidemiologic Studies; Exposure to; Face; Family; Fluorescence; Genes; Genetic Epistasis; Geographic Information Systems; Healthcare; Heart; Heart Atrium; Holt Oram syndrome; Imagery; In Situ Hybridization; Infant; Infant Mortality; Left; Life; Limb Development; Limb structure; Maps; Mediating; Microarray Analysis; Migrant Workers; Modeling; Molecular Profiling; Monitor; Myocardial; Myocardium; Neurotoxins; Nomads; Numbers; Occupational; Operative Surgical Procedures; Organophosphates; Pathway interactions; Personal Communication; Pesticides; Polychlorinated Biphenyls; Polymerase Chain Reaction; Poverty; Pregnancy; Proteins; RNA; Receptor Signaling; Reporter; Risk; Seasons; Signal Pathway; Signal Transduction; Societies; Staging; Structure; TP53 gene; Testing; Time; Tissues; Toxic effect; Toxin; United States Environmental Protection Agency; Universities; Up-Regulation; Ventricular; Washington; Western Blotting; Workplace; Zebrafish; base; cellular imaging; farm worker; loss of function; mutant; novel; reproductive; transcription factor

DESCRIPTION (provided by applicant): Hypoplastic left heart (HLH) is a grave congenital condition, uniformly fatal if untreated and requiring multiple surgeries for survival. Recently a cluster of HLH was discovered in children in the Baltimore-Washington area that correlated with accidental release of dioxins and polychlorinated biphenyls (PCBs). In an unrelated incident in Eastern NC during 2004, three migrant workers gave birth to infants with severe congenital defects, including one baby born without limbs, another with severe facial defects and associated heart abnormalities, and a third lacking reproductive structures who died shortly after birth; all birth defects were associated with pesticide overexposure. Strikingly, the PCB- induced HLH and pesticide associated birth defects may be related because PCBs and some pesticides disrupt cells by the same mechanism: activation of the aryl hydrocarbon receptor (AHR) signaling pathway which leads to tissue specific cell cycle arrest. Recently we created a novel model for toxin induced HLH in zebrafish where the AHR agonist PCB-126 induces a stringy heart with a reduced ventricle and out flow tract defects identical to those in HLH; remarkably, PCB-126 up regulates p53 and down regulates a heart specific transcription factor tbx5, implicated in Holt-Oram Syndrome and in HLH. We also found that the common organophosphate pesticide chlorpyrifos, both a developmental neurotoxin and AHR agonist, induces an enlarged atrium and a diminished ventricle reminiscent of that seen in PCB-treated zebrafish. Indeed, the cardiotoxicity common to PCB-126 and chlorpyrifos may reflect the fact that both are AHR agonists. We propose to create fluorescent reporter strains in zebrafish that will signal in living embryos when an AHR agonist disrupts cardiovascular development, and will use this approach to evaluate pesticides for developmental cardiotoxicity, particularly for teratogenic synergy. In Aim 1, we test the hypothesis that PCB-126 or chlorpyrifos activated AHR leads to down regulation of tbx5 followed by p53 mediated cell cycle arrest in the heart by using genetic epistasis and DNA microarray analysis. In Aim 2, fluorescent reporters in living zebrafish hearts will be constructed and then validated for use in signaling cardiotoxicity from exposure to PCB-126 and chlorpyrifos. The reporter strains then will be used to screen pesticides used in agriculture, in combinations and sequence typical of a growing season. We expect that our studies will provide a new testing paradigm to more accurately predict risk to EPA approved toxins as they are encountered routinely in real life. We seek to protect those in our society most vulnerable to toxin exposure those living in poverty, those with inadequate health care and migrant farm workers suffering occupational over exposure to pesticides.Hypoplastic left heart (HLH) is a grave congenital condition, uniformly fatal if untreated and requiring multiple surgeries for survival. Recently a cluster of HLH was discovered in children in the Baltimore-Washington area that correlated with accidental release of banned dioxins and polychlorinated biphenyls (PCBs). We have created a model for HLH in zebrafish where the AHR agonist, PCB-126, induces a stringy heart with a reduced ventricle and out flow tract defects identical to those seen in children with HLH. We propose to create fluorescent reporter strains in zebrafish that will signal in living embryos when an AHR agonist disrupts cardiovascular development and will use this approach to evaluate pesticides for developmental cardiotoxicity; we seek to protect those in our society most vulnerable to toxin exposure those living in poverty, those with inadequate health care and migrant farm workers suffering occupational over exposure to pesticides.

描述（由申请人提供）：左心（HLH）是一种严重的先天性状况，如果未治疗，则统一致命，需要多次手术才能生存。最近，在巴尔的摩 - 华盛顿地区的儿童中发现了一群HLH，这与意外释放二恶英和多氯联苯（PCB）相关。在2004年在北卡罗来纳州东部的一次无关事件中，三名移民工人诞生了患有严重先天性缺陷的婴儿，包括一个没有四肢的婴儿，另一个患有严重的面部缺陷和相关心脏异常的婴儿，以及第三个缺乏出生后不久死亡的生殖结构；所有先天缺陷均与农药过度暴露有关。引人注目的是，PCB诱导的HLH和与农药相关的先天缺陷可能是相关的，因为PCB和某些农药通过相同的机制破坏了细胞：芳基烃受体（AHR）信号传导途径的激活，从而导致组织特异性细胞周期的停滞。最近，我们在斑马鱼中创建了一个用于毒素诱导的HLH的新型模型，在该模型中，AHR激动剂PCB-126诱导了一个具有降低的心室和流出流缺陷的刺激性心脏，与HLH中的流动缺陷相同。值得注意的是，PCB-126向下调节p53及向下调节心脏特异性转录因子TBX5，与Holt-Oram综合征和HLH有关。我们还发现，一种发育性神经毒素和AHR激动剂的常见有机磷酸盐农药毒性雌雄同体会诱导心房增大，并降低心室，让人联想到PCB处理的斑马鱼中所见。实际上，PCB-126和毒死rif的心脏毒性可能反映出两者都是AHR激动剂的事实。我们建议在斑马鱼中创建荧光记者菌株，当AHR激动剂破坏心血管发育时，将在活着的胚胎中发出信号，并将使用这种方法来评估农药的发育性心脏毒性，尤其是对于致畸的协同作用。在AIM 1中，我们检验了以下假设：PCB-126或Chlorpyrifos激活AHR会导致降低TBX5的调节，然后使用遗传性Epistasis和DNA微阵列分析，然后使用p53介导的细胞周期停滞。在AIM 2中，将构建活着的斑马鱼心脏中的荧光记者，然后验证用于通过暴露于PCB-126和Chlorpyrifos的信号性心脏毒性。然后，记者菌株将用于筛选农业中使用的农药，结合和典型的生长季节。我们预计我们的研究将提供新的测试范式，以更准确地预测EPA认可的毒素的风险，因为它们在现实生活中经常遇到。我们寻求保护社会中最容易受到毒素暴露的人，那些生活在贫困中的人，那些没有足够的医疗保健和移民农场工人而遭受遭受农药暴露的职业的农场工人。Hypoppolastic左心（HLH）是一种严重的先天性状况，如果未经治疗，需要进行多种生存。最近，在巴尔的摩 - 华盛顿地区的儿童中发现了一群HLH，这与意外释放被禁止的二恶英和多氯联苯（PCB）相关。我们在斑马鱼中为HLH创建了一个模型，在该模型中，AHR激动剂PCB-126诱导了一个尖质的心脏，具有减少的心室和流动道与HLH儿童相同的心脏缺陷。我们建议在斑马鱼中创建荧光记者菌株，当AHR激动剂破坏心血管发育时，该菌株将在生存胚胎中发出信号，并将使用这种方法来评估农药的发育性心脏毒性；我们试图保护社会中最容易受到毒素暴露的人，那些生活在贫困中的人，医疗保健不足的人和移民农场工人因暴露于农药而遭受职业。