EMF EFFECTS ON CELL REGULATION IN A-T CELLS

EMF 对 A-T 细胞调节的影响

• 批准号: 2019341
• 负责人: LISE I LEBERG
• 金额: $ 10.64万
• 依托单位: IIT RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-01-10 至 1998-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2019341
• 关键词: DNA damage; DNA replication; ataxia telangiectasia; bleomycin; cell growth regulation; cyclins; electric field; enzyme activity; gene induction /repression; guanine nucleotide binding protein; human genetic material tag; human tissue; mitogen activated protein kinase; neurotoxicology; radiation genetics; radiobiology; tissue /cell culture; tumor suppressor proteins

EMF is an ubiquitous environmental exposure which may play a role in the induction of cancer. The actions of EMF in biological systems may be enhanced when exposure occurs in combinations with genotoxic insults. As such, plausible mechanism of action of EMF may be modulation of cellular responses to agents which damage DNA. The hypothesis of the proposed program is that EMF exposure alters the molecular regulatory pathways which are normally activated in cells exposed to DNA-damaging agents. The function of these pathways in normal cells is to induce cell cycle arrest, presumably to allow for repair of damage before DNA replication or mitosis takes place. A corollary hypothesis is that the effect of EMF exposure will be pronounced in cells cultured from patients with the genetic disease ataxia-telangiectasia (A-T). A-T cells have defects in DNA damage- induced cell cycle arrest and are sensitive to cell killing and chromosome damage after exposure to other components of the electromagnetic spectrum (i.e. ionizing and ultraviolet radiation). In the proposed experiments, A-T and normal cells will be exposed to bleomycin, a radiomimetic agent which damages DNA, followed by immediate exposure to EMF. Cell cycle progression and DNA synthesis activity will be measured by fluorescence-activated cell sorting (FACS) analysis. The molecular mechanism of EMF will be investigated by measuring components of signal transduction pathways known to be involved in the cellular response to DNA damage. G1/S arrest will be investigated by measuring p53 and related protein expression; DNA synthesis arrest will be investigated by measuring expression of cyclin A; G2/M arrest will be investigated by measuring cyclin B1. To elucidate whether EMF effects are transduced via cellular membranes, the MAP kinase cascade will be investigated by measuring transcription of c-jun and activation of the signal transducing kinases ERK1 and ERK2. Survival of A-T and normal cells following bleomycin/EMF exposure will also be measured, to determine whether EMF effects on cells impact on measurable biologic outcomes. These experiments are designed to investigate EMF effects on proliferation and survival of cells with prior exposure to a genotoxic agent. In addition, the mechanism of EMF action will be investigated by measuring various components of cellular regulatory pathways which lead to inhibition of cell cycle progression. These experiments will also determine whether cells cultured from A-T patients have unusual sensitivity to EMF effects.

电磁场是一种普遍存在的环境暴露， 诱发癌症 电磁场在生物系统中的作用可能 当暴露与遗传毒性结合时， 侮辱。 因此，EMF的合理作用机制可能是 调节细胞对损伤DNA的试剂的反应。的 该计划的假设是，电磁场暴露改变了 通常在细胞中被激活的分子调节途径 暴露在DNA破坏剂中 这些通路的功能 正常细胞是诱导细胞周期停滞，大概是为了允许 在DNA复制或有丝分裂发生之前修复损伤。 一 一个必然的假设是，电磁场暴露的影响将是 在遗传病患者的细胞培养中， 共济失调-毛细血管扩张（A-T）。 A-T细胞在DNA损伤方面有缺陷- 诱导细胞周期停滞，对细胞杀伤敏感， 染色体损伤后暴露于其他成分的 电磁光谱（即电离和紫外辐射）。 在拟议的实验中，A-T和正常细胞将暴露于 博来霉素，一种破坏DNA的拟辐射剂， 立即暴露于电磁场细胞周期进程和DNA合成 活性将通过荧光激活细胞分选来测量 （FACS）分析。 研究电磁场的分子机理 通过测量已知的信号转导途径的成分， 参与细胞对DNA损伤的反应。 G1/S逮捕将是 通过测量p53和相关蛋白表达进行研究; DNA 将通过测量以下物质表达来研究合成阻滞 将通过测量细胞周期蛋白B1来研究细胞周期蛋白A; G2/M停滞。 为了阐明EMF效应是否通过细胞传导， 膜，MAP激酶级联反应将通过测量 c-jun的转录和信号转导的激活 激酶ERK 1和ERK 2。 A-T细胞和正常细胞的存活， 还将测量博来霉素/EMF暴露，以确定EMF是否 对细胞的作用影响可测量的生物学结果。 这些 设计实验来研究EMF对增殖的影响 以及先前暴露于遗传毒性剂的细胞的存活。 在 此外，EMF作用的机制将通过以下方式进行研究： 测量细胞调节途径的各种组分， 导致细胞周期进程抑制。 这些实验将 还可以确定从A-T患者中培养的细胞是否具有异常的 对EMF效应的敏感性。