Oxidative Stress, Mitochondrial Dysfunction and Aging

项目描述(申请人提供)：本项目由三个研究项目和一个行政核心组成。我们的工作假说提出：(A)衰老组织表现出线粒体产生的ROS增加，导致(B)ROS产生的锁定循环放大氧化应激，以及(C)稳定ROS(D)引起的应激调节器的动态平衡变化，从而导致慢性应激状态和组织功能进行性下降。我们的PP关注的是这些由ROS介导的变化的后果。P1(JP)研究p38MAPK、其靶向转录因子和线粒体因子在衰老肝脏中的功能，以及对线粒体复合体I、II和III的抑制剂3-NPA、鱼藤酮和抗霉素A产生ROS信号的反应。作为分包商，WRW将确定由3-NPA产生的ROS的地点，并与所有3个项目进行机械互动。P2(SM)研究了衰老如何影响APE1在核和线粒体DNA修复中的作用；负钙反应元件(NCaRE)在钙反应基因表达调控中的作用；转基因小鼠核和APE水平的变化如何影响细胞对ROS的反应；应激诱导的APE1修饰的年龄依赖性调节是否影响老龄细胞的剪切和氧化应激反应。P3(IB)研究8氧鸟嘌呤DNA糖基酶(OGG1)对线粒体DNA修复的调节，以及与年龄相关的线粒体功能下降是否是由于OGGI的表达/活性变化、翻译后修饰和/或区域化引起的DNA修复受损/低效所致。这三个项目都有助于我们共同的PP目标，了解线粒体功能障碍产生的ROS的影响，以及蛋白质修饰如何影响应激反应的变化及其基因的活性，在每个项目中进行了研究。行政核心A将协助PI执行行政任务并协调动物使用。程序性的互动包括：积极的合作，共享组织以降低动物成本；积极的研讨会系列；以及关于实验设计、方法和数据分析的频繁磋商。通过在相同和不同的实验系统中采用一系列不同的方法来应对与年龄相关的应激反应的各种变化，我们将更清楚地识别影响适当组织功能随年龄下降的共同调节主题。

DESCRIPTION (provided by applicant): This Program Project consists of three research projects and an Administrative Core. Our working hypothesis proposes that (a) aging tissues exhibit an increase in mitochondrially generated ROS causing (b) a locked-in cycle of ROS production that amplifies oxidative stress and (c) stabilizes the homeostatic changes in regulators of the stress caused by the ROS (d) that result in a state of chronic stress and progressive decline in tissue function. Our PP is focused on the consequences of these ROS-mediated changes. P1 (JP) investigates the function of p38 MAPK, its targeted transcription factors and mitochondriai factors in the aged liver and in response to signals due to ROS generation by 3-NPA, rotenone, and antimycin A, inhibitors of mitochondrial complexes I, II and III. P1. A subcontractor, WRW will identify the site of ROS generated by 3-NPA and interact mechanistically with all 3 projects. P2 (SM) investigates how aging affects the role of APE1 in nuclear and mtDNA repair; the role of the negative Ca++ response element (nCaRE) in regulation of expression of Ca++ - responsive genes, how changing the nuclear and APE levels in transgenic mice affects the cellular response to ROS; whether the age-dependent modulation of stressinduced APE1 modification affects the shear and oxidative stress responses in aged cells. P3 (IB) investigates the regulation of mtDNA repair by 8 oxo-guanine DNA glycosylase (OGG1), and whether the age-associated decline in mitochondrial function is caused by impaired/inefficient DNA repair due to changes in expression/activity, posttranslational modification and/or compartmentalization of OGGI. All three projects contribute to our shared PP aims, to understand the effects of ROS generated by mitochondrial dysfunction and how protein modifications may affect changes in stress responses and the activity of their genes investigated in each project. The Administrative Core A will assist the PI in administrative tasks and coordinate animal use. Programmatic interactions include: active collaborations, sharing tissues to reduce animal costs; an active seminar series; and frequent consultations as to experimental design, methodology, and data analysis. By bringing a range of different approaches to bear on various age-related changes in stress response in the same and different experimental systems, we will more clearly discern common regulatory themes that affect the decline in proper tissue functions with age.