REGULATION OF RETINAL NEOVASCULARIZATION BY TIMP3

TIMP3对视网膜新生血管化的调节

• 批准号: 6363158
• 负责人: BELA ANAND-APTE
• 金额: $ 10.44万
• 依托单位: CLEVELAND CLINIC FOUNDATION
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6363158
• 关键词: SDS polyacrylamide gel electrophoresis; angiogenesis; angiogenesis inhibitors; blindness; cell migration; congenital eye disorder; enzyme activity; enzyme inhibitors; enzyme linked immunosorbent assay; fibroblast growth factor; gene mutation; human tissue; immunoprecipitation; membrane fusion; mixed tissue /cell culture; molecular cloning; northern blottings; pathologic process; polymerase chain reaction; protein binding; receptor binding; retina disorder; retinal pigment epithelium; tissue inhibitor of metalloproteinases; vascular endothelial growth factors; western blottings; SDS polyacrylamide gel electrophoresis; angiogenesis; angiogenesis inhibitors; blindness; cell migration; congenital eye disorder; enzyme activity; enzyme inhibitors; enzyme linked immunosorbent assay; fibroblast growth factor; gene mutation; human tissue; immunoprecipitation; membrane fusion; mixed tissue /cell culture; molecular cloning; northern blottings; pathologic process; polymerase chain reaction; protein binding; receptor binding; retina disorder; retinal pigment epithelium; tissue inhibitor of metalloproteinases; vascular endothelial growth factors; western blottings

Retinal neovascularization is an important pathological feature of eye diseases such as diabetic retinopathy and age related macular degeneration. A precise spatial and temporal regulation of extracellular proteolysis is required for neovascularization. Tissue Inhibitor of Metalloproteinase-3 (TIMP-3), a regulator of matrix metalloproteinases (MMPs), is deposited by retinal pigment epithelial (RPE) cells into Bruch s membrane (BM) where it is a component of the extracellular matrix. Mutations in the TIMP-3 gene cause Sorsby s fundus dystrophy (SFD), an inherited from of blindness. SFD is of considerable interest as it is the only genetic disorder in which haemorrhagic macular degeneration occurs in the majority of patients. We have demonstrated that TIMP-3 is an inhibitor of angiogenesis. Since choroidal neovascularization is a prominent feature of SFD we propose that TIMP-3 mutations in SFD may affect it s angiostatic function. It is hypothesized that under normal physiological conditions, endothelial cells are maintained in a quiescent state because of regulated balance between angiogenesis inducers and inhibitors. We propose the following model: TIMP-3 in the BM efficiently inhibits neovascular invasion from the choriocapillaris by a) Inhibiting MMP activity, resulting in an intact matrix and sequestration of angiogenic factors within the matrix and/or b) Binding directly to the surface of endothelial cells to inhibit endothelial cell responses. During pathological retinal neovascularization as seen in SFD, mutant TIMP-3 is compromised in this inhibitory activity which results in neovascularization. We propose to test this model with the following specific aims: 1. To determine the mechanism by which TIMP-3 inhibits angiogenesis. 2. To determine the direct effect of mutated SFD TIMP-3 protein or endothelial cells and angiogenesis. 3. To determine the mechanism by which mutated SFD-TIMP-3 secreted by RPE cells regulates endothelial cell responses. The broad long term goal of this proposal is to gain an understanding of the mechanism(s) by which alterations in matrix integrity may regulate retinal neovascularization using TIMP-3 mutations in SFD as a model.

视网膜新血管形成是眼睛的重要病理特征 糖尿病性视网膜病和与年龄相关的黄斑等疾病 退化。 精确的空间和时间调节 细胞外蛋白水解是新血管形成所必需的。组织 金属蛋白酶3（TIMP-3）的抑制剂，矩阵的调节剂 金属蛋白酶（MMP）通过视网膜色素上皮沉积 （RPE）细胞进入Bruch S膜（BM），其中它是该细胞的成分 细胞外基质。 TIMP-3基因中的突变引起Sorsby s 眼底营养不良（SFD），一种源自失明的遗传。 SFD是 兴趣很大，因为它是唯一的遗传疾病 大多数患者发生出血性黄斑变性。 我们已经证明TIMP-3是血管生成的抑制剂。 自从 脉络膜新生血管形成是我们提出的SFD的重要特征 SFD中的TIMP-3突变可能会影响其血管静脉功能。 它 假设在正常的生理条件下，内皮 由于调节的平衡，细胞保持静止状态 在血管生成诱导剂和抑制剂之间。我们提出以下内容 模型：BM中的TIMP-3有效抑制了来自 通过a）抑制MMP活性的脉络膜毛细血管，导致 完整的基质和基质内血管生成因子的固相关 和/或b）直接与内皮细胞表面结合到 抑制内皮细胞反应。 在病理视网膜期间 在SFD中看到的新血管化，突变体TIMP-3在此被妥协 抑制活性导致新血管形成。我们建议 以以下特定目的测试此模型：1。确定 TIMP-3抑制血管生成的机制。 2。确定 突变的SFD TIMP-3蛋白或内皮细胞的直接作用以及 血管生成。 3。确定突变SFD-TIMP-3的机制 由RPE细胞分泌的调节内皮细胞反应。 该提议的长期长期目标是获得理解 在基质完整性中改变的机制可能 使用SFD中的TIMP-3突变来调节视网膜新血管化 模型。