Role of TRPV4 and YAP/TAZ in Tendon Fibrosis and Engineered Tendon Development

项目摘要/摘要 在美国，每年有超过30万例肩袖手术。然而，治疗往往因以下原因而变得复杂 通过纤维化形成的松散的胶原基质，导致高再撕裂率。肌腱组织工程 寻求解决问题，使用生物材料促进新生肌腱的形成，以增强、修复或再生 肌腱。然而，尽管目前的生物材料提供了改善肌腱愈合的机会，但它们经常 在临床前研究中仍显示出纤维化。因此，迫切需要了解这些机制。 在为肌腱组织工程设计生物材料时形成排列一致的胶原蛋白。矩阵架构和 瞬时受体势阳离子通道V亚家族成员4(TRPV4)调节排列的胶原形成 在体外肌腱发生过程中，但其机制尚不清楚。最近，TRPV4的刺激是 发现可诱导转录共激活因子是相关蛋白(YAP)的核定位和激活 以及纤维化过程中角质形成细胞和肌成纤维细胞中具有PDZ结合基序的转录共激活因子(TAZ)。 在肌腱发育过程中，YAP的表达上调，这一过程的特征是胶原蛋白排列 形成，并对生理机械刺激的反应，表明它可能在 肌腱。TRPV4和YAP/TAZ在肺、肝、肾和心脏纤维化中均存在调节失调。然而， TRPV4和YAP/TAZ在肌腱纤维化中的作用及其相互作用尚未被研究。 工程化肌腱开发。总体假设是TRPV4通过 YAP/TAZ在生物材料上的肌腱形成过程中，刺激新生肌腱形成的程度与拉伸相似 正在装车。相反，YAP/TAZ和TRPV4之间这种关系的失调将促进纤维化基质的形成 证词。目的1比较YAP/TAZ和TRPV4在健康和纤维化肩袖肌腱中的作用。目标2 我将研究TRPV4和YAP/TAZ在肌腱形成过程中对齐胶原形成的相互作用 在“健康”和“纤维化”条件下的电纺生物材料上。AIM 3将评估TRPV4如何刺激 影响生物材料上的新生肌腱形成。这些信息将直接为计划中的临床前研究提供信息 最初在啮齿动物模型中进行肩袖修复，如果成功，则转移到大型动物模型和临床 翻译。完成拟议的学习将为我提供机会和培训，以支持我的 职业目标和发展所需的技能，以实现我的长期目标，独立教师的职业生涯在一个 研究密集型机构。

Project Summary/Abstract More than 300,000 rotator cuff surgeries occur annually in the US. However, treatment is often complicated by disorganized collagen matrix formed via fibrosis and results in high re-tear rates. Tendon tissue engineering seeks to solve the problem using biomaterials to promote neo-tendon formation to augment repair or regenerate tendon. However, while current biomaterials provide the opportunity to improve tendon healing, they frequently still exhibit fibrosis in preclinical studies. Therefore, a critical need exists to understand the mechanisms of aligned collagen formation when designing biomaterials for tendon tissue engineering. Matrix architecture and transient receptor potential cation channel subfamily V member 4 (TRPV4) regulate aligned collagen formation during tenogenesis in vitro, but the mechanism remains to be determined. Recently, TRPV4 stimulation was found to induce nuclear localization and activation of transcriptional co-activators Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) in keratinocytes and myofibroblasts during fibrosis. YAP expression is upregulated during tendon development, a process characterized by aligned collagen formation, and in response to physiological mechanical stimulation, suggesting it could play an important role in tendon. Both TRPV4 and YAP/TAZ are dysregulated in lung, liver, kidney, and cardiac fibrosis. However, the role of TRPV4 and YAP/TAZ, and their interactions, have not been investigated in tendon fibrosis or during engineered tendon development. The overall hypothesis is that TRPV4 regulates collagen alignment via YAP/TAZ during tenogenesis on biomaterials and stimulates neo-tendon formation to a similar extent as tensile loading. In contrast, dysregulation of this relationship between YAP/TAZ and TRPV4 will promote fibrotic matrix deposition. Aim 1 will compare the role of YAP/TAZ and TRPV4 in healthy and fibrotic rotator cuff tendon. Aim 2 will investigate the interaction between TRPV4 and YAP/TAZ in aligned collagen formation during tenogenesis on electrospun biomaterials in ‘healthy’ and ‘fibrotic’ conditions. Aim 3 will evaluate how TRPV4 stimulation affects neo-tendon formation on biomaterials. This information will directly inform planned preclinical studies of rotator cuff repair initially in rodent models, before, if successful, moving to large animal models and clinical translation. Completing the proposed studies will provide me with the opportunities and training to support my career goals and develop the skills I need to achieve my long-term goal of an independent faculty career at a research-intensive institution.