CELLULAR MECHANISMS OF PULMONARY ENDOTHELIAL INJURY

肺内皮损伤的细胞机制

• 批准号: 3346946
• 负责人: BARBARA O MEYRICK
• 金额: $ 27.66万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-05-01 至 1995-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3346946
• 关键词: Escherichia coli; adult respiratory distress syndrome; antiinflammatory agents; antioxidants; cell cell interaction; cell migration; complement pathway; cow; gene expression; high performance liquid chromatography; human tissue; humoral immunity; interleukin 1; lipoxygenase; phase contrast microscopy; prostaglandins; protein biosynthesis; pulmonary circulation; radiotracer; scanning electron microscopy; superoxide dismutase; tissue /cell culture; tumor necrosis factor alpha; vascular endothelium permeability

Pulmonary endothelial injury typifies the adult respiratory distress syndrome (ARDS). Gram negative bacterial sepsis is the most frequent clinical setting in which ARDS occurs, presumably a result of endotoxin- induced lung injury. In this renewal application, we propose to extend our observations of effects of endotoxin on lung endothelial cells in culture to a molecular level. We propose to test the hypothesis that endotoxin exposure results in increased oxidant stress within endothelial cells which causes increased production of interleukin-1 (IL-1) resulting in increased production of the antioxidant enzyme, manganous superoxide dismutase (MnSOD) (we have demonstrated that the first and last step in this sequence occur). Further, we propose that endotoxin stimulation of prostanoid production by endothelial cells is also oxidant mediated and that prostaglandin E2 (PGE2), a major product of microvascular endothelial cells, modulates IL-1 and thus MnSOD induction. We propose that differences in response of endothelial cells from different organs and from different sites within the lung can be explained by differences in constitutive production of MnSOD and PGE2 and that genetic engineering of endothelial cells to produce increased amounts of MnSOD will render the cells resistant to endotoxin-induced injury. To test these hypotheses we will conduct studies in cultured endothelial cells from large and small vessels in the lungs and from human umbilical veins. We will 1) elucidate the time course of induction of alteration in IL-1 and MnSOD gene expression following exposure of the cells to endotoxin and determine whether the responses are inhibited by antioxidants which access the cell interior, 2) determine whether the endotoxin effect are mimicked by the cytokine TNFalpha (which, like endotoxin, stimulates IL-1 production by endothelial cells) or exogenous IL-1, 3) determine effects of exogenous PGE2 on IL-1 and MnSOD gene expression, 4) compare these responses to endotoxin exposure in cells from different species, organs and sites, 5) determine whether endothelial cells genetically engineered to produce increased amounts of MnSOD are resistant to endotoxin effect and 6) initiate studies of the molecular mechanisms of endotoxin induction of MnSOD gene expression in endothelial cells. These studies follow logically the work supported by this grant over the past five years and promise a new level of understanding of how endotoxin affects endothelial cells and how the deleterious effects of endotoxin can be prevented. Such information will contribute to the development of novel interventions which may find eventual application in the clinical setting.

肺内皮损伤代表成人呼吸窘迫 综合征（ARDS）。 革兰氏阴性细菌败血症是最常见的 发生ARD的临床环境，可能是内毒素 - 诱发肺损伤。 在此续签应用中，我们建议扩展我们的 观察内毒素对培养中肺内皮细胞的影响 到分子水平。 我们建议检验内毒素的假设 暴露会导致内皮细胞内氧化应激增加，这 导致白介素1（IL-1）的产生增加，导致增加 产生抗氧化剂，锰超氧化物歧化酶 （MNSOD）（我们已经证明了此序列的第一步和最后一步 发生）。 此外，我们提出了前列腺素的内毒素刺激 内皮细胞的生产也是氧化剂介导的，并且 Prostaglandin E2（PGE2），微血管内皮的主要产物 细胞，调节IL-1，从而调节MNSOD诱导。 我们提出了这一点 来自不同器官的内皮细胞反应差异以及 肺内的不同地点可以通过差异来解释 MNSOD和PGE2的组成型生产以及该基因工程 内皮细胞产生增加的MNSOD，将使 细胞抗内毒素诱导的损伤。 为了检验这些假设我们 将在大小的大小 肺中的血管和人脐静脉。 我们将1）阐明 IL-1和MNSOD基因改变的诱导时间过程 暴露于细胞内内毒素并确定的表达 是否可以抑制抗氧化剂的反应的抗氧化剂 内部，2）确定内毒素作用是否被模仿 细胞因子tnfalpha（与内毒素一样，通过 内皮细胞）或外源性IL-1，3）确定外源性的影响 IL-1和MNSOD基因表达上的PGE2，4）将这些响应与 来自不同物种，器官和部位的细胞内毒素暴露，5） 确定内皮细胞是否基因工程为生产 MNSOD量增加对内毒素效应具有抗性，6） 开始研究内毒素诱导的分子机制 内皮细胞中的MNSOD基因表达。 这些研究从逻辑上遵循 在过去的五年中，这笔赠款支持的工作，并保证 对内毒素如何影响内皮细胞的理解水平以及如何 可以预防内毒素的有害作用。 这样的信息 将有助于发展新干预措施的发展 最终在临床环境中应用。