Acidosis in pulmonary endothelial injury and repair

项目总结/摘要 拟议的研究计划侧重于提高我们对酸中毒对肺炎影响的认识 并为诊断和治疗翻译建立概念基础。酸中毒在重症患者中很常见 肺炎患者，并与高死亡率。肺炎酸中毒的病理生理学是 目前的治疗方法无法改善主要结果。我们的研究表明， 微血管内皮细胞（PMVEC）利用碳酸酐酶IX（CA IX）同种型来调节pH， 代谢和迁移。我们还证明了铜绿假单胞菌感染PMVEC诱导 释放细胞毒性淀粉样蛋白，破坏肺泡毛细血管膜。这些细胞毒性淀粉样蛋白 诱导可溶性CA IX从PMVEC脱落，这损害了它们的修复潜力。基于这些 在初步研究中，我们检验了铜绿假单胞菌感染诱导细胞毒性淀粉样蛋白产生的假设， 导致可溶性CA IX在PMVEC中脱落，增加肺损伤。具体目标检验假设：1） CA IX对PMVEC的酸调节、代谢和迁移以及肺内皮屏障至关重要 完整性;和，2）铜绿假单胞菌感染诱发细胞毒性淀粉样蛋白产生，导致PMVEC中CA IX脱落， 从而增加肺损伤。在体外，我们将使用遗传方法和内皮细胞功能测定， 评估酸中毒的影响和特定CA IX功能域在生理和感染过程中的作用， 条件在体内和离体，我们将使用酸中毒，肺炎和隔离肺灌注小鼠模型， 翻译体外研究结果。这项研究的成功完成将提供新的见解的机制 肺炎中潜在的酸中毒，并帮助确定CA IX和细胞毒性淀粉样蛋白作为生物标志物和治疗 肺炎的目标。

PROJECT SUMMARY/ABSTRACT The proposed research plan focuses on improving our understanding of the effects of acidosis on pneumonia and establishing the conceptual basis for diagnostic and therapeutic translation. Acidosis is common in critically ill pneumonia patients, and is associated with high mortality. The pathophysiology of acidosis in pneumonia is poorly understood, and current therapies fail to improve major outcomes. Our studies have shown that pulmonary microvascular endothelial cells (PMVECs) utilize the carbonic anhydrase IX (CA IX) isoform to regulate pH, metabolism and migration. We also demonstrated that Pseudomonas aeruginosa infection of PMVECs induces release of cytotoxic amyloid proteins, which disrupts the alveolar capillary membrane. These cytotoxic amyloids induce soluble CA IX shedding from PMVECs which compromises their repair potential. Based on these preliminary studies, we test the hypothesis that P. aeruginosa infection induces cytotoxic amyloid production that leads to shedding of soluble CA IX in PMVECs, increasing lung injury. Specific aims test the hypotheses that: 1) CA IX is critical to the acid regulation, metabolism and migration of PMVECs and pulmonary endothelial barrier integrity; and, 2) P. aeruginosa infection elicits cytotoxic amyloid production, causing CA IX shedding in PMVECs, which increases lung injury. In vitro, we will use genetic approaches and endothelial cell functional assays to evaluate the effects of acidosis and the role of specific CA IX functional domains during physiologic and infectious conditions. In vivo and ex vivo, we will use acidosis, pneumonia and isolated lung perfusion mouse models to translate in vitro findings. Successful completion of this study will provide new insights into the mechanisms underlying acidosis in pneumonia and help identify CA IX and cytotoxic amyloids as biomarkers and therapeutic targets for pneumonia.