VIT E, SE OXIDANT STRESS AND PULMONARY ARACHIDATE SCASCA

拟议研究的主要目标是继续我们目前的研究， 研究阐明的分子基础， 前列腺素（PG）和白三烯（LT）生物合成的调节 维生素E和硒（Se）。 我们的假设是维生素E 和/或硒缺乏可影响与之相关的关键酶的表达， 随着PG和LT的生物合成以及它们在肺中的产物谱， 这种改变的类二十烷酸合成，部分原因是， 一些重要的生理功能受损，包括 免疫系统。 这个假设是基于这样一个前提， 酸性氢过氧化物（FAHP）和自由基是PG的组成部分， LT生物合成。 因此，通过维持临界浓度， FAHPs和必需自由基、Se-GSH-Px和维生素E具有 调节花生四烯酸级联的潜力。 拟议研究的具体目标是确定表达 （1）环氧合酶和5-脂氧合酶，催化第一个 （2）LTC 4合成酶是PG和LT生物合成的关键酶 参与硫代LT的生物合成;和（3）微粒体谷胱甘肽 S-转移酶是一种重要的GSH/GSSG依赖性蛋白， 抗氧化剂对肺膜过氧化损伤的保护 维生素E和/或硒缺乏症。 其他具体目标是（4） 详细检查，膳食维生素E和硒的地位对 巨噬细胞和中性粒细胞在肺中产生细胞因子，和（5） 为了研究维生素E和硒缺乏的潜在关系， 细胞因子的产生和花生四烯酸代谢的改变， 淋巴细胞功能 我们建议采用臭氧暴露作为额外的 氧化应激模型，以进一步阐明调节机制 潜在的抗氧化防御功能的维生素E和硒在PG和 LT生物合成。 分子探针如多克隆抗体、单克隆抗体和 将被用来确定改变的维生素C的作用是否 E和Se营养对与生长相关的关键酶表达的影响 花生四烯酸级联是在翻译水平或 转录水平。 我们还计划评估对酶的影响， 通过确定产品配置文件的活动水平。 实验将 还包括检查维生素E和/或硒的直接影响 白细胞产生细胞因子的缺陷-以及间接 已知受维生素E改变影响的类二十烷酸介导的效应 和硒营养。 最后，额外的实验将检查 可能解释细胞增殖和细胞毒性降低的机制 维生素E和/或硒缺乏的淋巴细胞的能力。 我们的长期目标是确定PG和LT的确切作用， 在这种情况下，氧化剂诱导的呼吸道疾病的病理生理学 抗氧化防御功能受损，如维生素E中所见， 和/或Se缺乏状态。

The primary objective of the proposed research is to continue our current investigations into the elucidation of the molecular basis for the regulation of prostaglandin (PG) and leukotriene (LT) biosynthesis by vitamin E and selenium (Se). Our working hypotheses are the vitamin E and/or Se deficiency can influence the expression of key enzymes associated with PG and LT biosynthesis as well as their product profiles in the lung, and this altered eicosanoid synthesis is, in part, responsible for the impairment of a number of critical physiological functions, including those of the immune system. this hypothesis is based on the premise that fatty acid hydroperoxides (FAHPs) and free radicals are integral parts of PG and LT biosynthesis. Therefore, by maintaining the critical concentrations of FAHPs and essential free radicals, Se-GSH-Px and vitamin E have the potential to modulate the arachidonic acid cascade. The specific aims of the proposed research are to determine the expression of (1) cyclooxygenase and 5-lipoxygenase, which catalyze the first committed step in PG and LT biosynthesis; (2) LTC4 synthase, a key enzyme involved in the biosynthesis of sulfido LTs; and (3) microsomal glutathione S-transferase, an important protein responsible for GSH/GSSG-dependent antioxidant protection against membrane peroxidative damage in the lung during vitamin E and/or Se deficiency. Additional specific aims are (4) to examine in detail, the role of dietary vitamin E and Se status on the production of cytokines in the lung by macrophages and neutrophils, and (5) to examine the potential relationships of vitamin E and Se deficiency, cytokine production, and arachidonic acid metabolism to alterations in lymphocyte function. We propose to employ ozone exposure as an additional oxidant stress model to delineate further the regulatory mechanisms underlying the antioxidant defense functions of vitamin E and Se in PG and LT biosynthesis. Such molecular probes as polyclonal antibodies, monoclonal antibodies and cDNAs, will be employed to determine whether the effects of altered vitamin E and Se nutrition on the expression of key enzymes associated with the arachidonic acid cascade are at the translational level or the transcriptional level. We also plan to assess the effects at the enzyme activity level by determining the product profiles. The experiments will also include the examination of direct effects of vitamin E and/or Se deficiency on cytokine production by leukocytes -- as well as indirect effects mediated by eicosanoids known to be affected by altered vitamin E and Se nutrition. Finally, additional experiments will examine the mechanisms that may explain the decreased proliferative and cytotoxic capabilities of lymphocytes by vitamin E and/or Se deficiency. Our long range objective is to establish the precise role of PGs and LTs in the pathophysiology of oxidant-induced respiratory diseases under such compromised antioxidant defense functions as those seen in vitamin E- and/or Se-deficient states.