Renal Cell Injury in Diabetes

描述（由申请人提供）： 项目摘要。申请人正在完成博士后奖学金，并将担任助理教授在终身职位的轨道有效10-1-06。申请人正在申请这项职业发展奖，并将由两名对本提案的主题材料感兴趣的医生科学家赞助。赞助商和共同赞助商都是经验丰富和富有成效的科学家，拥有成功的研究生，博士后研究员和初级教师的悠久历史。晚期糖基化终产物（AGEs）在糖尿病肾病（DN）等糖尿病并发症的发病机制中起着重要作用。AGEs通过AGEs特异性受体刺激活性氧（ROS）的产生，从而导致糖尿病肾病（DN）相关基因的上调。线粒体电子传递链产生的活性氧是糖尿病氧化应激的主要参与者，然而，本实验室的研究发现，肾脏中高表达的新型NAD（P）H-氧化酶是肾脏肥大和细胞外基质积聚（ECM）中活性氧的主要来源。在初步数据中，我们显示Nox 4定位于线粒体以及质膜。这项研究的目的是探讨AGE诱导的氧化应激在DN中的作用。我们将首先鉴定介导AGE诱导的活性氧产生（导致肾脏肥大和细胞外基质）的NAD（P）H-氧化酶亚基。其次，我们希望了解ROS产生的两个主要细胞来源，NAD（P）H-氧化酶和电子转移链之间的贡献和串扰。我们将在系膜细胞中评估这种新的联系，系膜细胞是主要参与肥大和ECM的肾脏细胞。最后，体内研究将使我们能够阐明NAD（P）H-氧化酶的作用和蛋白尿的分子机制，蛋白尿是DN的主要并发症，也是与糖尿病患者高度相关的重要问题。在长期实验中，通过递送反义NAD（P）H-氧化酶注射来减弱AGE诱导的基质积累和/或蛋白分泌，将证明NAD（P）H-依赖性ROS产生不仅有助于DN的起始，而且有助于其进展。我们的长期目标是将这项研究的结果转化为ROS生成的特异性抑制剂的发现。因此，氧化酶将成为未来治疗干预的主要靶标。我们的实验室拥有专业知识，我们的大学拥有所有可用的资源来解决这项赠款中提出的工作。 本案无关肾衰竭是糖尿病的常见并发症。我们的研究将探讨氧化应激诱导的修饰蛋白质（晚期糖基化终末产物-AGEs），积累在所有器官作为糖尿病环境的结果。阐明这些事件可能允许将来调节酶复合物，以防止与糖尿病细胞损伤有关的氧化应激。

DESCRIPTION (provided by applicant): Project Summary. The applicant is completing a post-doctoral fellowship and will assume a position as assistant professor in the tenure track effective 10-1-06. The applicant is applying for this career development award and will be sponsored by two physician scientists with a primary interest in the subject material of this proposal. Both sponsor and co-sponsor are experienced and productive scientists with long standing history of successful graduate students, postdoctoral fellows and junior faculty. Advanced glycation end-products (AGEs) play a central role in the pathogenesis of diabetic complications such as diabetic nephropathy (DN). AGEs stimulate reactive oxygen species (ROS) generation through AGE-specific receptors, which lead to the up-regulation of genes involved in diabetic nephropathy (DN). It has been suggested that ROS generated by the mitochondria electron-transfer chain is the major player in diabetic oxidative stress, however, research in our laboratory find novel NAD(P)H-oxidases, highly expressed in the kidney, to be major sources of ROS in renal hypertrophy and extracellular matrix accumulation (ECM). In preliminary data we show Nox4 localizes to mitochondria as well as plasma membrane. The objective of this grant is to explore the role of AGE-induced oxidative stress in DN. We will first identify the subunits of the NAD(P)H-oxidase(es) that mediate AGE-induced ROS generation which lead to renal hypertrophy and ECM. Secondly, we wish to understand the contribution and cross talk between two major cellular sources of ROS generation, NAD(P)H-oxidases and the mitochondria-electron transfer chain. We will evaluate this novel connection in mesangial cells, the cell of the kidney predominantly involved in hypertrophy and ECM. Finally, in vivo studies will allow us to elucidate the role of NAD(P)H-oxdase(es) and the molecular mechanisms involved in proteinuria, a major complication of DN and an important issue highly relevant for diabetic patients. An attenuation of AGE-induced matrix accumulation and/or protein secretion by delivery of anti-sense NAD(P)H-oxidase injection in the long-term experiments will demonstrate that NAD(P)H-dependent ROS generation contributes not only to the initiation of DN but also to its progression. Our long-term goal is to translate the findings from this research into the discovery of specific inhibitors of ROS generation. The oxdiase will thereby become a primary target for future therapeutic intervention. Our laboratory has the expertise and our University has all the resources available to address the work proposed in this grant. Relevance. Kidney failure is a common complication of diabetes. Our studies will examine oxidative stress induced by modified proteins (Advanced glycation end products-AGEs) that accumulate in all organs as a result of the diabetic environment. Elucidating these events may allow future modulation of the enzymatic complex(es) to prevent oxidative stress implicated in cellular injury in diabetes.