Novel therapies for VALI-induced edema

血管通透性的持续增加是呼吸机相关肺损伤和多器官衰竭的典型特征，它延长了生理紊乱的持续时间和对机械通气的需求。使用呼吸机天数的增加增加了营养不良和院内/呼吸机相关肺炎的风险。显然，迫切需要新的策略来减少接受通气患者的血管泄漏。项目4将利用完善的小鼠和犬VALI模型来识别新的分子靶点，并验证最近描述的与VALI诱导水肿形成有关的分子靶点。重要的是，我们将测试针对内皮细胞骨架的新型抗水肿策略，这是项目负责人进行的体外生理、生物物理、生化和分子研究的直接结果。SA #1将测试降低肺内皮中Ca+2/钙调素依赖性肌球蛋白轻链激酶（EC MLCK）活性的分子策略的效果，这是加西亚实验室首次克隆的一种关键的细胞骨架调节酶。EC MLCK密切参与炎症反应的多个方面，并直接参与EC屏障调节。SA #2将研究鞘氨醇1-磷酸（Sph 1-P）作为ALl动物模型的新疗法的疗效，Sph 1-磷酸是血小板介导的血管完整性的关键血管生成因子。我们证明了Sph 1-P在体外和体内产生快速、持续和剂量依赖性的屏障完整性增加。SA #3将使用降脂HMG Co A还原酶抑制剂辛伐他汀来减少vali诱导的水肿形成。最近

Sustained increases in vascular permeability, a defining feature ventilator-associated lung injury and multi-organ failure, prolongs the duration of physiologic derangement and the requirement for mechanical ventilation. Increased ventilator days enhance the risk of malnutrition and nosocomial/ventilator-associated pneumonia. Clearly there is a desperate need for new strategies to reduce vascular leak in patients receiving ventilation. Project 4 will utilize well-established models of murine and canine VALI to identify novel molecular targets and validate recently described molecular targets involved in VALI- induced edema formation. Importantly, we will test novel anti-edema strategies which target the endothelial cell cytoskeletal, a direct result of in vitro physiologic, biophysical, biochemical and molecular studies conducted by the Project Leader. SA #1 will test the effect of molecular strategies to reduce the activity of the Ca+2/calmodulin-dependent myosin light chain kinase in lung endothelium (EC MLCK), a critical cytoskeletal regulatory enzyme first cloned by the Garcia laboratory. EC MLCK is intimately involved in multiple aspects of the inflammatory response and directly participates in EC barrier regulation. SA #2 will examine the efficacy of sphingosine 1-phosphate (Sph 1-P), angiogenic factor critical to platelet-mediated vascular integrity, as novel therapy in animal models of ALl. We demonstrated that Sph 1-P produces rapid, sustained, and dose-dependent increases in the barrier integrity of in vitro and in vivo. SA #3 will utilize the lipid-lowering HMG Co A reductase inhibitor, simvastatin, to reduce VALI-induced edema formation. Recent reports including our own data, which indicate that the statins directly affect vascular remodeling, likely via the modulation of intracellular signaling mediated by Rho GTPases and Rho kinase, a pathway utilized by edemagenic agents (such as thrombin and VALI) to increase vascular leak. Finally, the identification of novel therapeutic targets for future barrier- protective strategies is essential for progress to be made in this devastating disorder. SA #4 will define murine strain differences in response to VALI-mediated vascular leak and utilize experimental progeny backcross strategies with genetic mapping of the murine genome to identify QTLs linked to susceptibility to VALI. The Project Leader, an authority on molecular mechanisms of vascular barrier regulation, combines exceptional complementary skills and experts in animal models of lung injury and mouse genetics. Given the profound physiologic derangements which accompany the vascular leak seen in VALI, we speculate that this project which will explore novel therapies and targets for VALI-induced pulmonary edema, will more quickly allow us to bridge the movement of scientific discovery into direct benefit for patients with Acute Lung Injury.