Novel therapies for VALI-induced edema

血管通透性的持续增加是呼吸机相关性肺损伤和多器官衰竭的一个明显特征，延长了生理性紊乱的持续时间和对机械通气的需求。呼吸机天数的增加增加了营养不良和医院/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机械通气的患者的血管渗漏。项目4将利用已建立的小鼠和犬VALI模型来识别新的分子靶点，并验证最近描述的与VALI诱导的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将测试降低肺内皮细胞钙离子/钙调蛋白依赖性肌球蛋白轻链激酶(EC MLCK)活性的分子策略的效果，EC MLCK是加西亚实验室首次克隆的一种关键细胞骨架调节酶。EC MLCK密切参与炎症反应的多个方面，并直接参与EC屏障的调节。SA#2将检验1-磷酸鞘氨醇(Sph1-P)作为ALL动物模型的新疗法的有效性，Sph1-P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Sph1-P在体外和体内产生快速、持续和剂量依赖的屏障完整性增加。SA#3将利用降脂的HMG Co A还原酶抑制剂辛伐他汀来减少VALI诱导的水肿形成。近期 包括我们自己的数据在内的报告表明，他汀类药物直接影响血管重塑，可能是通过Rho GTP酶和Rho K介导的细胞内信号调节，Rho K是水肿剂(如凝血酶和VALI)增加血管渗漏的途径。最后，为未来的屏障保护策略确定新的治疗靶点对于在这种破坏性疾病中取得进展至关重要。SA#4将定义对VALI介导的血管泄漏的反应的小鼠品系差异，并利用实验后代回交策略和小鼠基因组的遗传图谱来识别 与VALI易感性相关的QTL。项目负责人是血管屏障调节分子机制方面的权威，将肺损伤和小鼠遗传学动物模型方面的特殊互补技能和专家结合在一起。鉴于VALI的血管泄漏伴随着深刻的生理紊乱，我们推测这一项目将探索VALI引起的肺水肿的新疗法和靶点，将使我们更快地将科学发现的进展转化为对急性肺损伤患者的直接好处。

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.