Preprostaglandin Endoperoxides

描述(由申请人提供)：这项资助续期申请的重点是了解基于脂质的氧化蛋白修饰(OxPM)在眼病病因中的作用。我们推测oxPM可以干扰蛋白质的功能或导致病理性受体介导的反应。最主要的问题是：(1)oxPM是如何在体内产生的，(2)哪些蛋白质被修饰，(3)其病理后果是什么，以及(4)什么治疗干预措施可以防止oxPM的形成或阻止其受体介导的后遗症。生物实体必须适应生物分子容易发生的非酶反应，如自由基诱导的脂质氧化。了解这些倾向是我们解开疾病过程中脂质氧化参与的方法的基石。我们的研究导致了许多新的生物活性氧化脂质的鉴定，表征了它们与蛋白质的反应，并在分子水平上深入了解了这种氧化生物化学的病理后果。一种方法对我们来说特别有成效，就是了解脂肪氧化的化学和脂肪氧化产物的反应，然后调查这种化学的生物发生和后果。这些研究导致我们发现了左旋糖苷(LGs)和异丙酚(Isouglandins)，这两种极具活性的产物分别是酶和非酶脂肪氧化的产物，它们是通过内源性过氧化中间体的新重排产生的。由于它们在几秒钟内与蛋白质发生反应，这些隐形毒素在体内躲过了检测。但是，有了从“模型研究”中获得的它们的化学知识，我们设计了检测它们的蛋白质加合物的方法。它们在体内的形成现在已经牢固地建立起来，对它们参与一系列疾病过程的理解正在形成。我们未来四年的近期目标是了解：(1)LG和基于等LG的oxPM在青光眼和角膜炎的病因中的作用，以及维生素B6在防止它们在体内形成的效用，(2)羧烷基吡咯修饰的蛋白质在老年性黄斑变性、脉络膜和角膜中的参与！新生血管，以及(3)单链抗体用于阻断受体介导的对oxPM的病理反应。通过这些研究收集的了解将为预防、早期诊断和治疗与氧化损伤相关的眼部疾病提供新的方法。

DESCRIPTION (provided by applicant): This grant renewal application focuses on understanding the role of lipid-based oxidative protein modification (oxPM) in the etiology of eye diseases. We postulate that oxPM can interfere with protein function or result in pathological receptor-mediated responses. The overarching questions are: (1) how are oxPM generated in vivo, (2) which proteins are modified, (3) what are the pathological consequences, and (4) what therapeutic interventions can prevent oxPM formation or block their receptor-mediated sequelae. Biological entities must adapt to the nonenzymatic reactions, such as free radical-induced lipid oxidation, to which biomolecules are prone. Understanding these proclivities is the cornerstone of our approach to unraveling the involvements of lipid oxidation in disease processes. Our studies have resulted in the identification of many new biologically active oxidized lipids, characterization of their reactions with proteins, and molecular level insights into the pathological consequences of this oxidative biochemistry. One approach, that has been especially productive for us, is to learn about the chemistry of lipid oxidation and the reactions of lipid oxidation products, follow by an investigation of the biological occurrence and consequences of that chemistry. Such studies led to our discoveries of levuglandins (LGs) and isolevuglandins (isoLGs), extremely reactive products of enzymatic and nonenzymatic lipid oxidation, respectively, that are generated through novel rearrangements of endoperoxide intermediates. Because they react within seconds with proteins, these stealthy toxins evaded detection in vivo. But armed with knowledge of their chemistry obtained from "model studies", we devised methods to detect their protein adducts. Their formation in vivo is now firmly established, and an understanding of their involvement in a host of disease processes is emerging. Our immediate goals for the next four years are to understand: (1) the role of LG and isoLG-based oxPM in the etiology of glaucoma and keratitis, and the utility of vitamin B6 for preventing their formation in vivo, (2) the involvements of carboxyalkyl pyrrole-modified proteins in age-related macular degeneration, choroidal and cornea! neovascularization, and (3) the utility of single-chain antibodies for blocking receptor-mediated pathological responses to oxPM. The understanding gleaned through these studies will provide new approaches to the prevention, early diagnosis, and treatment of eye diseases associated with oxidative injury.