Environmental Beta Cell Toxins - Mechanisms of Action

环境β细胞毒素 - 作用机制

• 批准号: 7901694
• 负责人: Glenn Wilson
• 金额: $ 19.66万
• 依托单位: UNIVERSITY OF SOUTH ALABAMA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7901694
• 关键词: Animal Model; Animals; Antioxidants; Area; Autoimmune Process; Beta Cell; Cells; Chimeric Proteins; Cytoprotection; DNA; DNA Repair; DNA Repair Enzymes; Diabetes Mellitus; Disease; Dose; Evaluation; Foundations; Funding; Grant; Human; Inbred NOD Mice; Inflammation; Insulin-Dependent Diabetes Mellitus; Islets of Langerhans Transplantation; Mitochondria; Mitochondrial DNA; Modeling; Nitrogen; Oxygen; Pathogenesis; Peptides; Plague; Play; Procedures; Process; Proteins; Protocols documentation; Recombinant DNA; Recombinant Proteins; Research Design; Role; Streptozocin; Stress; Structure; Time; Toxic effect; Toxin; Transgenic Mice; Transplantation; Work; cytokine; design; innovation; islet; loss of function; novel; protective effect; repair enzyme; translational study

DESCRIPTION (provided by applicant): This is the competitive renewal of a grant which has been continuously funded for the past 23 years. During this time, we have made novel discoveries in the area of mitochondrial DNA damage and repair and how these processes play an important role in the pathogenesis of disease. The present application uses this work as a foundation to design new translational studies intended to develop innovative protocols to enhance the protection of this DNA in mitochondria. These strategies will be designed to block or delay the onset of type I diabetes and to protect islets used for transplantation against the loss of function and viability that occurs during islet isolation and in the early transplantation period. The first aim is designed to mechanistically evaluate and optimize the delivery of recombinant DNA repair enzymes and antioxidants to mitochondria in ¿-cells by protein transduction. These studies are structured to develop a more thorough understanding of the mechanisms involved in the protection of ¿-cells by protein transduction and to optimize the delivery of recombinant DNA repair and antioxidant proteins into mitochondria of ¿-cells by the TAT peptide. The second aim will evaluate the effects of the recombinant proteins developed in the first aim on the pathogenesis of diabetes in two animal models of type 1 diabetes. These studies are designed to determine whether the most effective recombinant protein or proteins, identified in the first aim to block ¿-cell toxicity caused by ROS, RNS and cytokines, can block the onset of diabetes in two animal models of type I diabetes when delivered into these animals by protein transduction. One animal model to be studied is the NOD mouse because diabetes in these animals appears to result from purely autoimmune mechanisms and recent work with these animals has indicated that there is a role for mtDNA in the pathogenesis of their disease. The second animal model to be studied is that produced by subdiabetogenic doses of the ¿-cell toxin streptozotocin (STZ). Transgenic mice which over-express the recombinant proteins in mitochondria of ¿-cells will be used for proof of principle. This model was chosen because diabetes is initiated by a ¿-cell toxin, STZ, and is associated with islet inflammation which resembles that seen in human type I diabetes. The final aim will evaluate the ability of fusion proteins to enhance the viability of islets to be used for transplantation. Although recently islet transplantation has proven to be a promising approach for the treatment of type I diabetes, this procedure has been plagued with problems relating to islet viability. The studies in this aim will explore whether the fusion proteins developed in the first aim can be used to help overcome this problem.

描述（由申请人提供）：这是对过去 23 年持续资助的一项资助的竞争性更新。在此期间，我们在线粒体 DNA 损伤和修复以及这些过程如何进行领域取得了新的发现。本申请以这项工作为基础来设计新的转化研究，旨在开发创新方案来增强线粒体中这种 DNA 的保护。 I 型糖尿病患者，要保护用于移植的胰岛，以防止胰岛分离期间和移植早期发生的功能和活力丧失。第一个目标是机械评估和优化重组 DNA 修复酶和抗氧化剂向线粒体的传递。 ¿这些研究的目的是为了更全面地了解涉及保护的机制。 -通过蛋白质转导细胞并优化重组DNA修复和抗氧化蛋白质向线粒体的递送第二个目标将评估第一个目标中开发的重组蛋白对两种 1 型糖尿病动物模型中糖尿病发病机制的影响。蛋白质，首先确定的目标是阻止 ¿当通过蛋白质转导将 ROS、RNS 和细胞因子引起的细胞毒性传递到两种 I 型糖尿病动物模型中时，可以阻止这些动物模型中糖尿病的发生。要研究的一种动物模型是 NOD 小鼠，因为这些动物中出现糖尿病。纯粹是自身免疫机制的结果，最近对这些动物的研究表明，线粒体 DNA 在其疾病的发病机制中发挥着作用。第二种要研究的动物模型是由亚糖尿病剂量的 ¿ -细胞毒素链脲佐菌素 (STZ) 转基因小鼠在 ¿ 线粒体中过度表达重组蛋白。 -细胞将用于原理证明，因为糖尿病是由 ¿ 引发的。细胞毒素 STZ 与胰岛炎症有关，类似于人类 I 型糖尿病，尽管最近胰岛移植已被证明，但最终目标是评估融合蛋白增强用于移植的胰岛活力的能力。作为治疗 I 型糖尿病的一种有前途的方法，该过程一直受到与胰岛活力相关的问题的困扰，该目标的研究将探索第一个目标中开发的融合蛋白是否可以用于帮助克服这个问题。