Mechanisms of anti-apoptotic effects induced by inhalable nanoparticles in neutrophilic granulocytes

吸入的疏水纳米颗粒诱导气道的炎症反应，其由嗜中性粒细胞主导。在暴露于环境纳米颗粒的人类中，这种嗜酸性肺部炎症可以显着促进慢性阻塞性肺病（COPD）或心血管疾病等疾病的发展。申请人的早期研究首次证明，碳纳米颗粒不仅触发嗜中性粒细胞肺部炎症，而且还增强了中性粒细胞水平的炎症反应。在人类嗜中性粒细胞中，暴露于碳纳米颗粒导致自然凋亡率的抑制，因此导致细胞寿命的延长和炎症反应的增强。使用基于细胞膜隔室稳定的干预策略，可以在体内系统和人体研究中证实这些发现的因果关系。由于纳米技术的快速发展，人类可能会接触到不同种类的纳米颗粒。该项目的目的之一是了解导致纳米颗粒延迟中性粒细胞凋亡的细胞和分子机制。由于暴露于碳纳米颗粒导致细胞内氧化应激，因此将采用适当的抗氧化策略研究诱导活性氧簇延迟凋亡的因果关系。作为诱导氧化应激的原因，一方面，纳米颗粒的固有氧化电位将通过使用氧化能力不同的模型颗粒来测试。另一方面，将通过使用药理学抑制剂和敲除策略来研究细胞的氧化系统。此外，膜偶联信号事件的相关性将在脂筏结构的水平上进行研究。同样，将通过干预策略研究这些事件的因果关系。另一个目的是评估颗粒特性，如化学组成，尺寸，反应表面和氧化电位，以确定其与纳米材料抗凋亡作用的相关性。这将使用人类接触的纳米材料进行研究。将通过时间序列和剂量反应实验估计材料延长嗜热菌寿命的潜力。除了使用人中性粒细胞的离体研究之外，还将进行使用咽部吸入纳米颗粒的动物模型的实验。将在暴露动物的支气管肺泡灌洗液中监测中性粒细胞凋亡的延迟。

Inhaled hydrophobic nanoparticles induce inflammatory reactions of the airways which are dominated by neutrophilic granulocytes. In humans exposed to environmental nanoparticles this neutrophilic lung inflammation can significantly contribute to the development of diseases like chronic obstructive pulmonary disease (COPD) or cardiovascular diseases. Earlier studies of the applicant for the first time demonstrated that carbon nanoparticles not only trigger neutrophilic lung inflammation but also enhance the inflammatory reaction at the level of the neutrophils. In human neutrophilic granulocytes exposure to carbon nanoparticles leads to a suppression of the natural apoptosis rate and therefore to a prolongation of the cellular life span and an enhancement of the inflammatory reaction. Using an intervention strategy based on the stabilisation of the membrane compartment of cells, the causality of these findings could be corroborated in an in vivo system and in a human study. Due to the rapid development of nanotechnology, humans may be exposed to different kinds of nanoparticles. One aim of the project is to understand the cellular and molecular mechanisms leading to the delay of neutrophil apoptosis by nanoparticles. As exposure with carbon nanoparticles leads to intracellular oxidative stress, the causality of the induction of reactive oxygen species for the delay of apoptosis will be studied with appropriate anti-oxidative strategies. As cause for the induction of oxidative stress, on one hand side the intrinsic oxidative potential of nanoparticles will be tested by the use of model particles differing with respect to their oxidative capacity. On the other hand side, oxidative systems of the cell will be investigated by the use of pharmacological inhibitors and a knock out strategy. Furthermore, the relevance of membrane-coupled signalling events will be investigated at the level of lipid raft structures. Again the causality of such events will be studied by intervention strategies. Another aim is to evaluate particle properties like chemical composition, size, reactive surface, and oxidative potential for their relevance for the anti-apoptotic effects of nanomaterials. This will be studied using a selection of nanomaterials to which humans are exposed. The potential of the materials to prolong the neutrophilic life span will be estimated by time series and dose response experiments. Besides ex vivo studies with human neutrophils, experiments using the animal model of pharyngeal aspiration of nanoparticles will be performed. The delay of neutrophil apoptosis will be monitored in broncho-alveolar lavage from exposed animals.