Fibrotic effects and regulation of MMP proteins in thrombus resolution

深静脉血栓形成(DVT)每年影响200多万美国人。静脉炎后综合征 可影响25%-75%的DVT患者，包括腿部肿胀、疼痛、皮肤变化和溃疡 皮肤。这只发生在DVT患者的一小部分中，这表明血栓溶解在 确定慢性静脉阻塞和纤维化是否会发展并导致静脉炎后 综合症。基质金属蛋白酶(MMP)基因对细胞迁移和组织重塑至关重要 在血栓溶解过程中表达和激活，表明在这一过程中起着关键作用。他们在其中扮演的角色 静脉炎后综合征的发病机制有三个具体的目的：1)定义 血栓诱导的基质金属蛋白酶-2基因及其同源转录因子的区域 2)检测MMP2、MMP9和MMP14(MT-MMPf)在DVT消退中的作用； 血栓诱导的静脉壁纤维化，3)确定基质金属蛋白酶蛋白(基质金属蛋白酶-2、基质金属蛋白酶-9)是否过表达 和基质金属蛋白酶-14)加速DVT的分解，并改变血栓诱导的静脉壁纤维化。一系列独特的 将使用转基因的基质金属蛋白酶-2报告小鼠来确定基质金属蛋白酶-2基因的哪些区域是必需的 对于血栓诱导的基质金属蛋白酶-2转录和染色质免疫沉淀将用于鉴定 同源转录因子。靶向缺失各种基质金属蛋白酶基因的小鼠将被用来确定 这些酶在血栓再通、静脉壁纤维化和静脉壁顺应性丧失中的作用 使用新的小鼠静脉生物力学分析方法的弹性。组织特异性转基因过表达 基质金属蛋白酶-2、-14和-9以及编码这些异构体的腺病毒载体将被用来过表达 这些蛋白质在血栓溶解过程中决定了DVT的溶解速度是加速的，并且对 纤维化和静脉壁的生物力学。这些研究将确定基质金属蛋白酶蛋白在有益和 血栓溶解的不利方面，并表征潜在的分子治疗以防止后 静脉炎综合征。 相关性：这项提议将确定基质金属蛋白酶蛋白如何导致瘢痕形成和 血液凝块后血管变厚，这会导致后来的腿部疼痛、肿胀和溃疡。这些研究将 增加关于血栓如何损害静脉的知识，并测试新的治疗方法以防止这种损害。

Deep venous thrombosis (DVT) affects more than 2 million Americans per year. Post-phlebitic syndrome can affect 25-75% of patients following DVT and includes leg swelling, pain, skin changes and ulceration of the skin. This develops only in a subset of DVT patients, suggesting that thrombus resolution is critical in determining whether chronic venous obstruction and fibrosis will develop and lead to post-phlebitic syndrome. Matrix metalloproteinase (MMP) genes, critical to cell migration and tissue remodeling, are expressed and activated during thrombus resolution suggesting a critical role in this process. Their role in the pathogenesis of post-phlebitic syndrome will be defined with three Specific Aims: 1) To define the regions of the MMP-2 gene and cognate transcription factors critical to thrombus-induced MMP-2 expression, 2) To determine the role of MMP-2, MMP-9 and MMP-14 (MT-MMP-f) in DVT resolution and thrombus-induced vein wall fibrosis, 3) To determine if overexpression of MMP proteins (MMP-2, MMP-9 and MMP-14) accelerates DVT resolution and alters thrombus-induced vein wall fibrosis. A unique series of transgenic MMP-2 reporter mice will be used to determine which regions of the MMP-2 gene are essential for thrombus-induced MMP-2 transcription and chromatin immunoprecipitation will be used to identity the cognate transcription factors. Mice with targeted deletion of various MMP genes will be used to determine the role of these enzymes in thrombus recanalization, vein wall fibrosis and loss of vein wall compliance and elasticity using novel assays of mouse vein biomechanics.Tissue-specific transgenic overexpression of MMP-2, -14 and -9 as well as adenoviral vectors encoding these isoforms will be utilized to overexpress these proteins during thrombus resolution to determine resolution of DVT is accelerated and the effects on fibrosis and vein wall biomechanics.These studies will define the role of MMP proteins in the beneficial and detrimental aspects of thrombus resolution, and characterize potential molecular therapy to prevent post- phlebitic syndrome. RELEVANCE: This proposalwill determine how matrix metalloproteinase proteins cause scarring and thickening of veins after blood clots, which can cause later leg pain, swelling and ulcers. These studies will increase knowledge of how veins are damaged by clots and test new treatments to prevent this damage.