Differential mechano-signaling in vascular endothelium by varying degrees of mechanical stretch - Resubmission 01

通过不同程度的机械拉伸在血管内皮中产生差异性机械信号 - 重新提交 01

• 批准号: 9754858
• 负责人: Anna Birukova
• 金额: $ 38.63万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9754858
• 关键词: Adaptor Signaling Protein; Address; Adherens Junction; Blood Vessels; Cells; Cellular Mechanotransduction; Characteristics; Complex; Data; Down-Regulation; Drug Targeting; Edema; Endothelial Cells; Endothelium; Environment; Environmental air flow; Event; Exposure to; Extravasation; Functional disorder; Guanine Nucleotide Exchange Factors; Guanosine Triphosphate Phosphohydrolases; Heart failure; Hyperemia; Hypoxia; Inflammation; Inflammatory; Intercellular Junctions; Intervention; Lead; Leukocytes; Life; Liquid substance; Lung; Mechanical Stress; Mechanical ventilation; Mechanics; Microcirculatory Bed; Microvascular Permeability; Molecular; Monomeric GTP-Binding Proteins; Names; Nucleotides; Nutrient; Organ; Pathologic; Pathology; Pathway interactions; Periodicity; Permeability; Physiological; Pilot Projects; Play; Property; Pulmonary Edema; Pulmonary Hypertension; Recovery; Redness; Regulation; Role; Signal Pathway; Signal Transduction; Specific qualifier value; Stretching; Stroke; Swelling; Testing; Tidal Volume; Tight Junctions; Time; Tissues; Variant; Vascular Endothelial Cell; Vascular Endothelium; Vascular Permeabilities; Ventilator-induced lung injury; in vivo; mechanical force; mechanotransduction; mouse model; novel; preconditioning; recruit; response; restoration; rho; rho GTP-Binding Proteins; tumor; vascular endothelium permeability

Differential mechano-signaling in vascular endothelium by varying degrees of mechanical stretch Excessive mechanical forces imposed on the microvascular endothelium lead to increased microvascular permeability accompanying life-threatening conditions such as stroke, pulmonary hypertension, or ventilator induced lung injury, to name a few. We have previously characterized signaling pathways induced in vascular endothelium by high magnitude cyclic stretch (CS) and described a key role of Rho GTPase in high CS- induced endothelial barrier dysfunction. However, cellular mechanotransduction complexes which transform mechanical signals to cellular responses remain to be characterized. Our unpublished pilot studies indicate that Rap1 signaling is activated by physiologically relevant low magnitude (5%) CS and promotes re-assembly of tight junctions disrupted by cell preconditioning at pathologically relevant high magnitude (18%) CS. The preliminary data also suggest that low CS-induced EC barrier restoration is associated with accumulation of adaptor protein cingulin at the tight junctions and formation of cingulin-GEF-H1 complex. The central hypothesis tested in this application is that recovery of vascular endothelial barrier after pathologic mechanical stress may be accelerated by cell exposure to physiologic CS levels and involves Rap1-dependent reassembly of endothelial tight junctions, recruitment of cingulin to the tight junctions, and stimulation of cingulin - GEF-H1 interaction. These events lead to inhibition of GEF-H1 nucleotide exchange activity, suppression of Rho- dependent barrier disruptive mechanisms, and accelerated recovery of the vascular endothelial barrier. The following questions will be addressed: Aim-1 will study cingulin-dependent mechanisms of endothelial barrier regulation by physiologic mechanical stretch. Aim-2 will study the role of cingulin in downregulation of the Rho pathway in mechanically stimulated microvascular endothelium after a switch from pathologic to physiologic CS amplitude. Aim-3 will evaluate cingulin-dependent vascular protective mechanisms in a mouse model of mechanical ventilation.

通过不同程度的机械拉伸，血管内皮中的差分机械信号 施加在微血管内皮上的过多的机械力导致微血管增加 伴随着威胁生命的状况（例如中风，肺动脉高压或呼吸机）的渗透性 诱发肺部受伤，仅举几例。我们以前已经表征了在血管中诱导的信号通路 内皮通过高幅度循环拉伸（CS），并描述了Rho GTPase在高CS-的关键作用 诱导内皮屏障功能障碍。但是，转化的细胞机械转导复合物 对细胞反应的机械信号仍有待表征。我们未发表的试点研究表明 RAP1信号通过生理相关的低幅度（5％）CS激活，并促进重新组装 在病理相关的高幅度（18％）CS处细胞预处理的紧密连接处。这 初步数据还表明，低CS诱导的EC屏障恢复与积累有关 在紧密连接处和c蛋白-GEF-H1复合物的形成下的衔接蛋白c蛋白。中央 在此应用中检验的假设是病理学后血管内皮屏障的恢复 细胞暴露于生理CS水平，可能会加速压力，并涉及RAP1依赖性重新组装 内皮紧密连接，将金属蛋白募集到紧密连接的连接蛋白以及刺激Cingulin -GEF -H1 相互作用。这些事件导致抑制GEF-H1核苷酸交换活性，抑制Rho- 依赖性屏障破坏性机制，并加速了血管内皮屏障的恢复。这 将解决以下问题：AIM-1将研究内皮屏障的依赖于c蛋白的机制 通过生理机械拉伸调节。 AIM-2将研究cingulin在下调Rho中的作用 从病理学转变为生理学后，机械刺激的微血管内皮中的途径 CS振幅。 AIM-3将评估依赖金素依赖性血管保护机制的小鼠模型 机械通气。