The role of NOX4 and its interaction with mitochondria and Nrf2 in hyperexcitability-induced neurodegeneration

NOX4 的作用及其与线粒体和 Nrf2 的相互作用在过度兴奋诱导的神经变性中的作用

• 批准号: 408780607
• 负责人: Dr. Stjepana Kovac, Ph.D.
• 金额: --
• 依托单位: Klinik für Neurologie mit Institut für Translationale Neurologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/408780607?language=en
• 关键词: role; NOX4; its; interaction; mitochondria

Hyperexcitability is a common mechanism leading to neurodegeneration in a plethora of central nervous system (CNS) diseases. It occurs amongst others in epilepsy and multiple sclerosis (MS) where reactive oxygen species (ROS) have been shown to play a role. Despite overwhelming evidence of their critical role in neurodegeneration, targeting ROS has been challenging, and clinical trials aimed at scavenging ROS, once they have been produced, have largely failed. One explanation for this is that scavenging of ROS with direct antioxidants is futile since large doses and a sustained supply of antioxidants are needed, which by themselves might have other adverse effects. Thus, targeting sources of ROS, rather than ROS once they have already been produced, represents an appealing strategy. This in turn requires a careful characterization of the sources of ROS production, as some may be beneficial to the cell.We have previously shown that nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidases, which are enzymes highly specialized in ROS production, play a pivotal role in hyperexcitability-induced neurodegeneration. Seven different isoforms of NADPH oxidases exist (NOX1-5, and DUOX1 and 2). In preliminary experiments, we recently found high expression of NOX4 in brain resident cells, and that NOX4 interacts both with mitochondria and nuclear factor erythroid 2–related factor 2 (Nrf2). On the one hand, these interactions are important since energy depletion and thus mitochondria, as the “powerhouses of the cell”, play a lead role in hyperexcitability-induced neurodegeneration. On the other hand, the transcription factor Nrf2, which upon activation drives transcription of antioxidant proteins, has also been shown to contribute to neurodegeneration during hyperexcitability. This implies that targeting NOX4 is likely a promising strategy to combat hyperexcitability-induced neurodegeneration.We here propose to first study the impact of NOX4 on hyperexcitability-induced neurodegeneration and the interaction between NOX4 and mitochondria and NOX4 and Nrf2 during hyperexcitability. This will be done with live cell imaging techniques in different brain resident cells (astrocytes, neurons, endothelial cells and microglia) in addition to molecular biology analyses in NOX4-deficient mice. Next, we will use a mouse model of hyperexcitability-induced neurodegeneration to study the role of NOX4, taking advantage of global and tissue-specific NOX4-deficient animals, i.e. mice with a NOX4 deficiency in endothelial or neuronal tissue (NOX4endo -/- and NOX4neuro -/-) and live-cell imaging analyses in brain slices in addition to electrophysiology and immunohistochemistry. Finally, we will corroborate data obtained from animal experiments by analysing post mortem human brain tissues of patients suffering from MS, a disease characterized by hyperexcitability-induced neurodegeneration, using immunohistochemistry.

过度兴奋性是导致多个中枢神经系统（CNS）疾病中神经退行性的常见机制。它发生在癫痫和多发性硬化症（MS）中，其中活性氧（ROS）已显示出作用。尽管有很多证据表明其在神经变性中的重要作用，但针对ROS的靶向却受到了挑战，并且旨在清除ROS的临床试验一旦产生，就已经大大失败了。对此的一种解释是，由于需要大剂量和持续的抗氧化剂供应，因此对ROS进行清除是徒劳的，这本身可能会产生其他不利影响。这是针对ROS的来源，而不是一旦产生了ROS，就代表了一种吸引人的策略。反过来，这又需要仔细表征ROS产生的来源，因为有些可能对细胞有益。我们先前表明烟酰胺腺苷二核苷酸磷酸氧化酶（NADPH）氧化物是高度专门用于ROS产生的酶，在低脑性能力性诱导的神经脱发中起着重要的作用。存在七个不同的NADPH氧化物同工型（NOX1-5，DUOX1和2）。在初步实验中，我们最近发现NOX4在脑居民细胞中的高表达，并且NOX4与线粒体和核因子红细胞2相关因子2（NRF2）相互作用。一方面，这些相互作用很重要，因为能量定义，因此是“细胞的强力室”，在过度刺激性诱导的神经变性中起着铅作用。另一方面，在激活驱动抗氧化剂蛋白的转录后，转录因子NRF2也已被证明在过度兴奋期间有助于神经变性。这意味着靶向NOX4可能是打击过度抗性诱导的神经退行性的承诺策略。我们在这里提出的建议是首先研究NOX4对过度抗性诱导的神经变性的影响以及NOX4，Mitochondria和Mitochondria和Nox4和Nox4和Nox4和NRF2的影响。除NOX4缺陷小鼠中的分子生物学分析外，还将使用不同脑居民细胞（星形胶质细胞，神经元，内皮细胞和小胶质细胞）中的活细胞成像技术来完成。 Next, we will use a mouse model of hyperexcitability-induced neurodegeneration to study the role of NOX4, taking advantage of global and tissue-specific NOX4-deficiency animals, i.e. mice with a NOX4 deficiency in endothelial or neuronal tissue (NOX4endo -/- and NOX4neuro -/-) and live-cell imaging analyses in brain slices in addition to electrophysiology and免疫组织化学。最后，我们将使用免疫组织化学使用免疫组织化学来证实从动物实验中获得的数据，该分析是通过MS的患者进行分析，这种患者是患有MS的患者，这种疾病是使用免疫组织化学的疾病。