TGF-Beta in Intimal Hyperplasia after Vascular Bypass

描述（由申请人提供）：内膜增生和/或收缩 重塑是血管性疾病复发的主要原因， 重建转化生长因子-β（TGF-β）是一种重要的 细胞因子，已被发现是整体参与这两个 流程.该提案的目标是探索TGF-β在 内膜增生病理生理学中的信号中间体， 收缩性重塑我们将专门研究一个家庭， 细胞内信号蛋白，称为SMAD，以及它们在这两个过程中的作用。 流程.我们的实验室和其他研究表明，TGF-β抑制了平滑肌细胞的生长， 肌肉细胞（SMC）增殖和刺激凋亡;功能， 限制内膜增生。相反，TGF-β刺激细胞外基质 生产（胶原蛋白I是主要的I型），这是一种增强 增生性病变的形成。在初步实验中，我们有 发现：Smads选择性地介导TGF-β的作用。具体地说， Smad 3刺激胶原蛋白表达，但对SMC增殖没有影响。 Smad 3在平滑肌细胞中的这些差异功能可能使我们能够设计分子设计， 可以选择性地保留“抑制”效果，但阻止 TGF-β对内膜增生的“刺激”作用。研究中 在本提案中详细说明，我们将进一步定义Smad 3和其他的角色 Smad蛋白在血管平滑肌细胞功能中的作用在具体目标中，我们将评估 Smads在SMC中的功能通过瞬时排除野生型和显性型 阴性突变Smads以及SMC功能报告基因进入SMC 线然后，我们将创建腺病毒载体，表达选定的Smads， 似乎对SMC生理学有显著影响，并在 人原代血管SMC。在具体目标II中，我们将探讨 TGF-β与I型胶原基因的启动子。最终目标 设计一种寡核苷酸诱饵， 一种胶原蛋白转录的选择性遗传抑制剂。最后，具体而言， 目的III：我们将检验刺激和/或抑制Smads的假设， 或者选择性抑制胶原促进剂可以限制 大鼠血管损伤模型中内膜增生。我们预计 这些研究的结果都将提高我们的病理生理学知识， 内膜增生，并允许设计新的治疗方法， 抑制这种影响数千名患者的复杂人类疾病过程 每年.

DESCRIPTION (Provided by Applicant): Intimal hyperplasia and/or constrictive remodeling are major causes of recurrent disease following vascular reconstruction. Transforming growth factor-beta (TGF- beta) is an important cytokine that has been found to be integrally ' involved in both of these processes. The goal of this proposal is to explore the role of TGF-beta signaling intermediates in the pathophysiology of intimal hyperplasia and constrictive remodeling. We will specifically examine a family of, intracellular signaling proteins, termed SMADs, and their role in these two processes. Our laboratory and others have shown that TGF-beta inhibits smooth muscle cell (SMC) proliferation and stimulates apoptosis; functions that would limit intimal hyperplasia. Conversely, TGF-beta stimulates extracellular matrix production (collagen I being the predominant I type), an effect that enhances the formation of hyperplastic lesions. In preliminary experiments, we have found that: Smads selectively mediate the effects of TGF-beta. Specifically, Smad3 stimulates collagen expression but has no effect on) SMC proliferation. These differential functions of Smad3 in SMCs may allow us to design molecular tools that can selectively preserve the "inhibitory" effects but block the "stimulatory" effects of TGF-beta on intimal hyperplasia. In the studies detailed in this proposal, we will further define the role of Smad3 and other Smad proteins in vascular SMC function. In specific aim I we will evaluate the function of Smads in SMC by transiently transfecting wild type and dominant negative mutant Smads as well as reporter genes for SMC function into SMC lines. We will then create adenoviral vectors that express selected Smads that appear to have a significant impact on SMC physiology and test their effect in human primary vascular SMC. In specific aim II, we will explore the interaction of TGF-beta with the promoter of the gene of type I collagen. The ultimate goal of these experiments will be to design an oligonucleotide decoy that can act as a selective genetic inhibitor of collagen transcription. Finally, in specific aim III we will test the hypothesis that stimulation and/or inhibition of Smads or selective inhibition of the collagen promoter can limit the formation of intimal hyperplasia in a rat model of vascular injury. We anticipate that the results of these studies will both enhance our knowledge of the pathophysiology of intimal hyperplasia and also allow for the design of novel therapies to inhibit this complex human disease process which affects thousands of patients each year.