Protection by Induction of Ubiquitin-Proteasome Systems

泛素-蛋白酶体系统的诱导保护

• 批准号: 6813892
• 负责人: MI-KYOUNG KWAK
• 金额: $ 19.35万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2006-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6813892
• 关键词: aging; animal tissue; cell age; cell line; conformation; cytoprotection; dithiol; embryo /fetus; genetic regulation; genetically modified animals; hazardous substances; immunocytochemistry; laboratory mouse; neural degeneration; neurogenetics; neuropharmacology; oxidative stress; proteasome; protein structure function; proteolysis; sulfur aminoacid; transcription factor; ubiquitin

DESCRIPTION (provided by applicant): Damaged proteins and their aggregated products are formed during oxidative stress and aging. 26S proteasomes can recognize and remove these damaged and unfolded proteins; moreover, decreased function of the ubiquitin-proteasome system is associated with the development of age-related degenerative diseases. It is our hypothesis that maintenance or enhancement of ubiquitin-proteasome function is a novel strategy to prevent or attenuate these age-related diseases. Our preliminary results indicate that dithiolethiones, which protect against the toxicities of environmental agents by stimulating expression of the downstream genes of the Nrf2 signaling pathway, increase expression of multiple subunits of 26S proteasomes and ubiquitinating enzymes in mouse liver. This proposal is designed to a) evaluate the physiological benefit of induced proteasome expression in cells following challenge by toxicants, b) determine the impact of inducible proteasome expression and the role of Nrf2 on the accumulation of damaged proteins in young and senescence murine fibroblasts as a model of aging, c) characterize inducible patterns and levels of proteasome expression in murine tissues, especially in the brain, following dithiolethione-treatment. Functional effects of enhanced proteasome induction will be initially investigated in cultured cells using murine embryonic fibroblasts and neuroblastoma cells. Measures of proteasome levels, proteolytic activities, protein turnover rates and accumulation of damaged proteins following chemical challenge will be compared in cell models in which proteasome expression is elevated by pharmacological intervention and through molecular genetic expression of specific proteasome subunits. The role of Nrf2 in these protective effects will be examined using nrf2-disrupted or inhibited cells as well as by comparisons in wild-type and nrf2-deficient mice of different ages. Collectively, these studies will explore the possible protective role of enhanced proteasome expression against exogenous toxic chemicals and degenerative processes that accompany aging. The long-term goal of this project is to rigorously evaluate the concept that increased expression of ubiquitin-proteasomes pathway through activation of the Nrf2 signaling cascade can prevent or retard the progression of human degenerative diseases such as Alzheimer's, Parkinson's disease and amyotrophic lateral sclerosis.

描述（由申请人提供）： 在氧化应激和衰老期间形成受损的蛋白质及其聚合产物。 26S蛋白酶体可以识别并去除这些受损和展开的蛋白质；此外，泛素 - 蛋白酶体系统功能的降低与与年龄相关的退行性疾病的发展有关。我们的假设是，维持或增强泛素 - 蛋白酶体功能是预防或减弱这些与年龄有关的疾病的新型策略。我们的初步结果表明，通过刺激NRF2信号通路的下游基因的表达来预防环境药物的毒性，增加26S蛋白酶体的多个亚基的表达以及小鼠肝脏中的泛素酶的表达。该提案旨在a）评估毒性挑战的细胞中诱导蛋白酶体表达的生理益处，b）确定可诱导蛋白酶体表达的影响以及NRF2对年轻和衰老鼠类成纤维成纤维细胞中受损蛋白质的累积的作用，作为粘液的模型，c）的表达，尤其是在诱导的模型中，尤其是在脑中的表达。二硫代治疗。最初，使用鼠类胚胎成纤维细胞和神经细胞瘤细胞在培养的细胞中最初研究增强蛋白酶体诱导的功能作用。将在细胞模型中比较蛋白酶体水平，蛋白质水解活性，蛋白质更新速率和受损蛋白质的积累，在这些细胞模型中，通过药理学干预和特定蛋白酶体亚基的分子遗传表达升高蛋白酶体的表达。 NRF2在这些保护效果中的作用将使用NRF2破坏或抑制的细胞以及不同年龄的野生型和NRF2缺陷小鼠的比较来检查。总的来说，这些研究将探讨增强蛋白酶体表达对外源有毒化学物质和衰老伴随的退化过程的保护作用。该项目的长期目标是严格评估以下概念，即通过激活NRF2信号传导级联反应增加了泛素 - 蛋白酶体途径的表达可以预防或阻碍人类退化性疾病的发展，例如阿尔茨海默氏症，帕金森氏病和肌萎缩性的后期嗜血杆菌。