DNA repair and DNA damage response for the maintenance of endothelial cell function during genotoxic stress

基因毒性应激期间维持内皮细胞功能的 DNA 修复和 DNA 损伤反应

• 批准号: 253890300
• 负责人: Professor Dr. Gerhard Fritz
• 金额: --
• 依托单位: Institut für Toxikologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/253890300?language=en
• 关键词: DNA; repair; damage; response; maintenance

A number of autosomally recessive hereditary disorders is characterized by increased genomic instability, caused by insufficient DNA repair and a related increase of tumor incidence. One of these disorders is the Werner syndrome, which is characterized not only by a repair defect but also by an accelerated ageing process in affected patients (adult progerie). Contrary to other known genetic instability syndromes, post-pubescent Werner patients develop rapid and pronounced geriatric symptoms such as osteoporosis, diabetes mellitus (type II) and arteriosclerosis. Arteriosclerical changes (myocardial infarction, apoplexis) are, besides tumor development, the most significant reason for the relatively short lifespan (40 to 50 yrs) of Werner patients. The defective gene in these patiens encodes the RecQ helicase (WRN). This DNA helicase is essentially involved in DNA repair and DNA damage-dependent stress responses, caused by, among others, reactive oxygen species (ROS) or alkylating agents. ROS-induced DNA damage compromises the physiological function of endothelial cells (endothelial dysfunction), hence being relevant for the pathogenesis of arteriosclerosis. Whether DNA methylation, which can result from endogenous formation of nitrosamines, impacts endothelial cell functions is poorly investigated. We posit that impairment of WRN associated DNA repair and stress responses impacts the endothel cell-related functions, which eventually result in the known cardiovascular complications observed in Werner patients. In addition, we hypothesize that DNA repair in general, also independent of WRN, is a major determinant for the preservation of endothel cell function. Using primary human endothelial cells we will address the question to which extent an RNAi mediated downregulation of WRN, WRN associated and WRN independent DNA repair factors influences endothelial cell function following genotoxic stress provoked by oxidants and alkylating agents. Bearing in mind that statins are well known vessel protective therapeutics, we aim to investigate their potency for maintaining endothelial function and viability following genotoxic stress even under conditions of compromised DNA repair.

许多常染色体隐性遗传性疾病的特征在于由DNA修复不足引起的基因组不稳定性增加以及相关的肿瘤发病率增加。这些疾病之一是沃纳综合征，其特征不仅在于修复缺陷，而且还在于受影响患者的加速老化过程（成人早衰症）。与其他已知的遗传不稳定综合征相反，青春期后Werner患者发展迅速和明显的老年症状，如骨质疏松症，糖尿病（II型）和动脉硬化。动脉硬化改变（心肌梗死、中风）是Werner患者相对较短寿命（40 - 50岁）的最重要原因。这些患者的缺陷基因编码RecQ解旋酶（WRN）。这种DNA解旋酶主要参与DNA修复和DNA损伤依赖性应激反应，这些反应由活性氧（ROS）或烷化剂等引起。ROS诱导的DNA损伤损害内皮细胞的生理功能（内皮功能障碍），因此与动脉硬化的发病机制相关。是否DNA甲基化，这可能导致内源性形成亚硝胺，影响内皮细胞功能的研究很少。我们认为WRN相关的DNA修复和应激反应的损伤会影响内皮细胞相关的功能，最终导致在Werner患者中观察到的已知心血管并发症。此外，我们假设DNA修复一般也独立于WRN，是内皮细胞功能保存的主要决定因素。使用原代人内皮细胞，我们将解决的问题，在何种程度上RNAi介导的下调WRN，WRN相关和WRN独立的DNA修复因子影响内皮细胞功能后，由氧化剂和烷化剂引起的遗传毒性应激。考虑到他汀类药物是众所周知的血管保护性治疗药物，我们的目标是研究其在遗传毒性应激后维持内皮功能和活力的效力，即使在受损的DNA修复条件下。