Role of MMPs in TGFbeta-induced Cataract Formation

MMPs 在 TGFbeta 诱导的白内障形成中的作用

• 批准号: 8188198
• 负责人: Judith A West-Mays
• 金额: $ 24.27万
• 依托单位: MCMASTER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8188198
• 关键词: Adhesions; Anterior; Antibodies; Blindness; Cataract; Cataract Extraction; Cell Adhesion Molecules; Cell-Cell Adhesion; Complication; Crystalline Lens; Data; Developed Countries; Development; Disease; E-Cadherin; Epithelial; Epithelial Cells; Event; Extracapsular; Eye; Fibrosis; Funding; Gelatinase A; Gelatinase B; Goals; Grant; Lead; Link; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Mediating; Mediator of activation protein; Mesenchymal; Modeling; Molecular; Mus; Mutant Strains Mice; Myofibroblast; North America; Nuclear Translocation; Operative Surgical Procedures; Organ; Pathway interactions; Play; Prevention; Rattus; Recombinants; Research; Role; Signal Pathway; Signal Transduction; Smooth Muscle Actin Staining Method; Testing; Therapeutic; Tissues; Transforming Growth Factor beta; Wild Type Mouse; Work; cost; design; epithelial to mesenchymal transition; in vivo Model; inhibitor/antagonist; lens; lens transparency; morphogens; mouse model; myocardin; prevent; research study; transcription factor; treatment strategy

DESCRIPTION (provided by applicant): Epithelial-mesenchymal transition (EMT) has been shown to play an important role in the fibroses of multiple organs and tissues, including the ocular lens, where it contributes to both anterior subcapsular cataracts (ASC) and posterior capsular opacification (PCO), also known as secondary cataract. Increased proliferation of lens epithelial cells (LECs), and EMT of LECs into myofibroblasts, involving a loss of the cell-cell adhesion molecule E-cadherin and an induction in ?-smooth muscle actin (?SMA) expression are early events in both ASC and PCO. Transforming growth factor beta (TGF?) is a pleotropic morphogen that has been shown to induce the EMT of LECs and subsequent formation of ASC, as well as, PCO. Using a previously developed rat lens culture model in which exogenous TGF? induces ASC we have shown that treatment with inhibitors to the matrix metalloproteinases (MMP), specifically MMP-2 and MMP-9, suppresses TGF? -induced cataractous changes, including EMT. Studies from the previous grant period further show that these two MMPs likely work cooperatively and/or redundantly in the development of these cataracts. For example, using a model of ASC involving the delivery of Ad TGF? to the eye we have shown that MMP-9 KO mice develop cataracts, albeit they are delayed compared to wild-type mice. Thus, inhibiting both MMPs may be required to prevent EMT and subsequent cataractogenesis. The potential mechanism by which these MMPs mediate EMT and cataract formation was identified during the previous funding period and involves disruption of E-cadherin. Preliminary data suggests that disruption and shedding of E-cadherin results in downstream signaling events linked to EMT including nuclear translocation of ?-catenin and the myocardin-related transcription factor (MRTF-A). However, the requirement for these signaling intermediates in ASC and PCO and how MMPs are involved is not known. In the current application we investigate these TGF? -mediated signaling pathways using multiple ex vivo and in vivo models of ASC and PCO. In addition, we outline experiments that will directly determine the unique and/or cooperative roles of MMP-2 and MMP-9 in ASC formation. Ultimately, our goal is to define the TGF? - mediated pathways controlling EMT and fibrosis in ASC and PCO in order to design therapeutics for mitigating these diseases. PUBLIC HEALTH RELEVANCE: Loss of transparency of the lens, or cataract, is the leading cause of blindness worldwide despite the availability of effective surgery in developed countries. Extracapsular cataract extraction is the most frequently performed surgical procedure in North America, costing over 3.5 billion dollars each year, and can frequently lead to complications such as the development of secondary cataract (posterior capsular opacification (PCO). Thus, an understanding of the cellular and molecular mechanisms regulating the normal and pathological differentiation of the lens is necessary in order to develop therapeutic strategies for the treatment and/or prevention of cataracts. In the proposed research we will investigate the cell signaling mechanisms responsible for two fibrotic cataracts, anterior subcapsular cataracts (ASC) and PCO and further determine how these mechanisms can be inhibited. Specifically we will focus on those pathways mediated by transforming growth factor beta (TGF?) and the matrix metalloproteinases (MMPs) since both of have been implicated in these cataracts. Ultimately, it is hoped that the data obtained from the proposed studies will lead to therapeutic strategies for mitigating cataract formation.

描述（由申请人提供）：已证明上皮间质转变（EMT）在包括眼镜在内的多个器官和组织的纤维中起着重要作用，在这些器官和组织的纤维纤维中，它在其中有助于前囊膜下白内障（ASC）和后囊闭囊（ASC）和后囊闭合（PCO）（PCO），也称为次要caartact。透镜上皮细胞（LEC）和LEC的EMT的增殖增加，涉及细胞 - 细胞粘附分子E-钙粘着蛋白的丧失，以及对smooth肌肉肌动蛋白（？sma）的诱导，在ASC和PCO中都是早期事件。转化生长因子β（TGF？）是否已显示出可诱导LEC的EMT以及随后的ASC以及PCO的形成的多余形态学。使用先前开发的大鼠透镜培养模型在哪种外源性TGF中？诱导ASC我们已经表明，用抑制剂对基质金属蛋白酶（MMP），特别是MMP-2和MMP-9进行治疗会抑制TGF？ - 诱导的白内障变化，包括EMT。从上一个赠款期开始的研究进一步表明，这两个MMP可能在这些白内障的发展中进行合作和/或冗余。例如，使用涉及AD TGF的ASC模型？在眼中，我们已经表明MMP-9 KO小鼠会出现白内障，尽管与野生型小鼠相比，它们延迟了。因此，可能需要抑制两种MMP以防止EMT和随后的白内垂直生成。这些MMP介导EMT和白内障形成的潜在机制在上一个资金期间被鉴定出来，并涉及E-钙粘着蛋白的破坏。初步数据表明，E-钙粘着蛋白的破坏和脱落会导致与EMT相关的下游信号事件，包括？ - 卡氨酸的核易位和与肌动蛋白相关的转录因子（MRTF-A）。但是，尚不清楚这些信号中间体以及ASC和PCO中这些信号中间体的需求。在当前的应用程序中，我们研究了这些TGF？ - 使用多个EX和PCO的体内模型介导的信号通路。此外，我们概述了将直接确定MMP-2和MMP-9在ASC组中的独特和/或合作作用的实验。最终，我们的目标是定义TGF？ - 控制ASC和PCO中EMT和纤维化的介导途径，以设计用于减轻这些疾病的治疗剂。 公共卫生相关性：尽管发达国家有有效的手术，但镜头或白内障的透明度丧失还是世界范围内的主要原因。囊外白内障提取是北美最常执行的手术程序，每年耗资超过35亿美元，并且经常会导致并发症，例如次级性白内障的发展（后胶囊透光化（PCO）（PCO）。因此，对细胞和分子的理解进行了对正常和病理学的理解，以使其对正常和病理学的理解，以使其在范围内进行策略，以使其在le孔中的策略差异化，从而在le虫中进行了策略。白内障。在拟议的研究中，我们将研究导致两个纤维化白内障的细胞信号传导机制，前囊式白内障（ASC）和PCO进一步确定这些机制如何抑制这些机制。最终，希望从拟议的研究中获得的数据将导致减轻白内障形成的治疗策略。