Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA.
Veterans Affairs Healthcare System, Iowa City, Iowa, USA.
JCI Insight. 2017 Feb 9;2(3):e88297. doi: 10.1172/jci.insight.88297.
Excessive ROS promote allergic asthma, a condition characterized by airway inflammation, eosinophilic inflammation, and increased airway hyperreactivity (AHR). The mechanisms by which airway ROS are increased and the relationship between increased airway ROS and disease phenotypes are incompletely defined. Mitochondria are an important source of cellular ROS production, and our group discovered that Ca/calmodulin-dependent protein kinase II (CaMKII) is present in mitochondria and activated by oxidation. Furthermore, mitochondrial-targeted antioxidant therapy reduced the severity of allergic asthma in a mouse model. Based on these findings, we developed a mouse model of CaMKII inhibition targeted to mitochondria in airway epithelium. We challenged these mice with OVA or . Mitochondrial CaMKII inhibition abrogated AHR, inflammation, and eosinophilia following OVA and . challenge. Mitochondrial ROS were decreased after agonist stimulation in the presence of mitochondrial CaMKII inhibition. This correlated with blunted induction of NF-κB, the NLRP3 inflammasome, and eosinophilia in transgenic mice. These findings demonstrate a pivotal role for mitochondrial CaMKII in airway epithelium in mitochondrial ROS generation, eosinophilic inflammation, and AHR, providing insights into how mitochondrial ROS mediate features of allergic asthma.
活性氧(ROS)过度会促进过敏性哮喘,其特征是气道炎症、嗜酸性粒细胞炎症和气道高反应性(AHR)增加。ROS 增加的机制以及增加的气道 ROS 与疾病表型之间的关系尚未完全确定。线粒体是细胞 ROS 产生的重要来源,我们的研究小组发现钙/钙调蛋白依赖性蛋白激酶 II(CaMKII)存在于线粒体中,并被氧化激活。此外,靶向线粒体的抗氧化治疗可减轻过敏性哮喘小鼠模型的严重程度。基于这些发现,我们开发了一种靶向气道上皮细胞线粒体 CaMKII 抑制的小鼠模型。我们用 OVA 或 对这些小鼠进行了挑战。OVA 和 后,线粒体 CaMKII 抑制可阻断 AHR、炎症和嗜酸性粒细胞增多。在存在线粒体 CaMKII 抑制的情况下,激动剂刺激后线粒体 ROS 减少。这与 NF-κB、NLRP3 炎性小体和转基因小鼠嗜酸性粒细胞增多的诱导减弱相关。这些发现表明,线粒体 CaMKII 在气道上皮细胞中线粒体 ROS 生成、嗜酸性粒细胞炎症和 AHR 中具有关键作用,为了解线粒体 ROS 如何介导过敏性哮喘的特征提供了线索。