ASBESTOS AND NO2 IN ENVIRONMENTAL LUNG DISEASE

描述 人肺暴露于环境颗粒物和气体 导致多种疾病，包括肺纤维化， 癌 我们研究小组以前的工作表明，石棉， 活性氧（ROS）和活性氮（RNS）触发 肺靶细胞中的特定细胞信号传导途径，导致 转录因子如AP-1和NF-κ B的激活。 这些和其他 转录因子参与细胞决策， 表型改变参与了肺部疾病的发生。 延长 我们对细胞对化学和物理混合物的反应的理解 因此，我们建议研究温石棉和氮的影响， 二氧化物（NO2），单独或一起，对三个接触终点： 细胞存活、细胞周期进展和凋亡。 一是 表征大鼠肺上皮（RLE）细胞和大鼠肺的响应 成纤维细胞（RLF）对石棉和/或N 02的活化， 转录因子AP-1、NF-κ B和E2 F及其下游靶点 基因. 细胞周期蛋白依赖性激酶（CDK）的活化，其代谢 蛋白质抑制剂（即，CKIs p15、p16、p18、p21和p27），和 视网膜母细胞瘤家族蛋白质（pRB和p130）的磷酸化将被抑制。 作为细胞周期进程的调节剂进行研究。 细胞成像技术， 流式细胞术和蛋白酶的活化将用于测量细胞凋亡 应答 显性负调控分子的瞬时表达 将被用来剖析暴露反应的机制。 用于生理 相关性，使用细胞周期控制模型的实验结果， 将通过使用小鼠的吸入研究来验证体外细胞凋亡。 最后，为了测试特定蛋白质如p53，CKIS， 和其它候选细胞周期调节剂在细胞周期活化中的作用，和/或 通过石棉和N 02的细胞凋亡，吸入研究将在 缺乏特定目的基因的转基因小鼠。 角色剖析 细胞周期和存活调节因子在增殖和凋亡中的作用 对石棉和N 02的综合影响的反应可能导致新的 人类肺部暴露于化学混合物的生物标志物。

DESCRIPTION Exposure of the human lung to environmental particulates and gases contributes to a variety of diseases, including pulmonary fibrosis and cancer. Previous work in our research group has shown that asbestos, reactive oxygen species (ROS), and reactive nitrogen species (RNS) trigger specific cell signaling pathways in target cells of the lung, leading to activation of transcription factors such as AP-1 and NF-KB. These and other transcription factors are involved in cellular decisions leading to phenotypic changes involved in the initiation of lung disease. To extend our understanding of cellular responses to mixtures of chemical and physical agents, we propose to study the effects of chrysotile asbestos and nitrogen dioxide (NO2), either alone or together, on three endpoints of exposure: cell survival, cell cycle progression, and apoptosis. First, we will characterize the responses of rat lung epithelial (RLE) cells and rat lung fibroblasts (RLF) to asbestos and/or N02, in regard to the activation of the transcription factors AP-1, NF-KB, and E2F and their downstream target genes. Activation of cyclin-dependent kinases (CDKs), metabolism of their protein inhibitors (i.e., CKIs p15, pl6, pl8, p2l, and p27),and phosphorylation of retinoblastoma family proteins (pRB and pl3O) will be studied as regulators of cell cycle progression. Cell imaging techniques, flow cytometry and activation of proteases will be used to measure apoptotic responses. Transient expression of dominantnegative regulatory molecules will be used to dissect mechanisms of exposure responses. For physiological relevance, results from experiments using models for cell cycle control and apoptosis in Vitro will be verified by inhalation studies using mice. Finally, to test the contributions of specific proteins such as p53, CKIS, and other candidate cell cycle regulators in cell cycle activation and/or apoptosis by asbestos and N02, inhalation studies will be performed in transgenic mice lacking specific genes of interest. Dissection of the role of cell cycle and survival regulators in proliferative and apoptotic responses to the combined effects of asbestos and N02 may lead to new biomarkers for exposure of the human lung to chemical mixtures.