Molecular Signaling in Cataracts

白内障的分子信号传导

• 批准号: 9364322
• 负责人: Jonathan Mark Petrash
• 金额: $ 38.88万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9364322
• 关键词: Adaptor Signaling Protein; Address; Adopted; Aldehyde Reductase; Aluminum; Animal Model; Attenuated; Binding; Blindness; Caregivers; Cataract; Cataract Extraction; Cell Membrane Permeability; Cells; Clinical; Combined Modality Therapy; Complex; Development; Docking; Drug Targeting; Epithelial; Epithelial Cells; Excision; Extracapsular; Eye; Eye diseases; Fibroblasts; Genes; Genetic Transcription; Growth Factor; Interruption; Knockout Mice; Lasers; Lead; Light; Link; Measures; Mediating; Mediator of activation protein; Medical; Mesenchymal; Modeling; Molecular; Morphology; Mus; Operative Surgical Procedures; Pathogenesis; Pathogenicity; Patients; Pharmacologic Substance; Pharmacology; Phenotype; Physiologic Intraocular Pressure; Prevalence; Prevention; Prevention strategy; Procedures; Process; Proliferating; Proteins; Quality of life; Recruitment Activity; Reporting; Retinal Detachment; Retinal Edemas; Risk; Signal Transduction; Signaling Protein; Smad Proteins; Smooth Muscle Actin Staining Method; Surgical complication; Testing; Therapeutic; Therapeutic Agents; Thinness; Time; Transforming Growth Factor beta; Transforming Growth Factor beta Receptors; Transgenic Mice; Treatment Efficacy; Visual Acuity; Work; World Health Organization; Yttrium; arm; blind; capsule; cell behavior; comparative; cytokine; design; diabetic; diabetic cataract; enzyme pathway; epithelial to mesenchymal transition; fiber cell; global health; high risk; inhibitor/antagonist; lens; mouse model; mutant; polyol; prevent; protein biomarkers; receptor; response; synergism; wound

Project Summary Cataract is one of the major causes of blindness worldwide. Following surgical removal of the cataractous lens, approximately 20% of cataract patients develop posterior capsular opacification (PCO) and significantly compromised quality of life. Given the prevalence of cataract and the relatively high rate of PCO following cataract surgery, especially among young patients who develop a more aggressive PCO as well as the increasing number of diabetics at higher risk to develop PCO, there is an urgent need for therapies to prevent cellular changes that lead to this blinding condition. There is currently no medical therapy to effectively prevent PCO and no alternative to capsulotomy for its treatment. Thus, the long-term impact of this work will address a currently unmet clinical need—the prevention of PCO using pharmaceutical agents to suppress growth factor signaling responsible for PCO development. Transforming growth factor-beta (TGF-β) is recognized as one of the major growth factors that drive PCO pathogenesis. TGF-β induces activation of Smad proteins, which then bring about transcription of a battery of genes involved in the shift of epithelial cells to a mesenchymal phenotype, known as epithelial-to-mesenchymal transition (EMT). In preliminary studies we showed that aldose reductase (AR), a polyol pathway enzyme linked to diabetic eye disease, facilitates Smad activation by TGF-β. Proposed studies seek to devise therapeutic strategies to interrupt the pathogenic signals that drive the PCO process. In Aim 1, we will use transgenic mouse models as a platform to test the hypothesis that AR facilitates EMT in PCO pathogensis. Comparative risk for PCO development will be measured in our AR-Tg mice, AR null mice (ARKO), and wild type C57BL6 mice, using immunostaining and quantitative PCR to measure EMT and structural markers in the lens at various times following surgery. In Aim 2, we will decipher the mechanism linking AR to TGFß-mediated signaling in PCO development. We will utilize mutant forms of AR and TGFß-receptor adaptor proteins to test the hypothesis that AR interferes with Smad-activation through its interactions with accessory proteins involved with Smad recruitment to the receptor complex. In Aim 3, we will explore two different therapeutic strategies to block EMT signaling in animal models of PCO. First we will test the hypothesis that pharmacological blockade of AR is sufficient to prevent cellular changes associated with PCO development. In a second arm of this study, we will test the ability of a membrane-permeable form of Smad7, an inhibitor of Smad signaling, to attenuate EMT in our mouse model of PCO. We will also investigate a combination therapy involving combined use of an AR inhibitor and Tat-Smad7. These studies aim to clarify molecular mechanisms leading to PCO and lead to therapeutic strategies for its prevention.

项目摘要 白内障是世界范围内致盲的主要原因之一。手术摘除白内障透镜后， 大约20%的白内障患者发生后囊混浊（PCO）， 生活质量受损。考虑到白内障的患病率和PCO的相对较高的发生率， 白内障手术，特别是在年轻患者谁开发一个更积极的PCO以及 越来越多的糖尿病患者处于发展PCO的较高风险，迫切需要治疗以预防PCO。 导致失明的细胞变化目前还没有有效预防的药物治疗方法 后囊膜混浊，除晶状体囊切开术外无其他治疗方法。因此，这项工作的长期影响将解决 目前尚未满足的临床需求-使用抑制生长因子的药物预防PCO 负责PCO开发的信令。转化生长因子-β（TGF-β）被认为是 驱动PCO发病机制的主要生长因子。TGF-β诱导Smad蛋白的活化， 引起一系列基因的转录，这些基因与上皮细胞向间充质细胞的转变有关， 表型，称为上皮-间充质转化（EMT）。在初步研究中，我们发现， 醛糖还原酶（AR）是一种与糖尿病眼病相关的多元醇途径酶，通过以下途径促进Smad活化： 转化生长因子β。拟议的研究试图设计治疗策略，以中断驱动免疫系统的致病信号。 PCO过程。在目标1中，我们将使用转基因小鼠模型作为平台来检验AR 在PCO发病中促进EMT。将在我们的AR-Tg中测量PCO发展的比较风险 小鼠、AR敲除小鼠（ARKO）和野生型C57 BL 6小鼠，使用免疫染色和定量PCR， 在手术后的不同时间测量透镜中的EMT和结构标记。在目标2中，我们将破译 在PCO发展中，AR与TGF β介导的信号传导的联系机制。我们将利用变异的 AR和TGF β-受体衔接蛋白，以检验AR通过以下途径干扰Smad激活的假设： 其与辅助蛋白的相互作用涉及Smad向受体复合物的募集。在目标3中，我们 将探索两种不同的治疗策略，以阻断PCO动物模型中的EMT信号。首先我们将 检验AR的药理学阻断足以防止相关细胞变化的假设 PCO的发展。在本研究的第二部分中，我们将测试膜渗透形式的能力 Smad 7，一种Smad信号抑制剂，在我们的PCO小鼠模型中减弱EMT。我们亦会研究 联合使用AR抑制剂和Tat-Smad 7的联合治疗。这些研究旨在澄清 导致PCO的分子机制，并导致其预防的治疗策略。