Research Project II - Vesicant-Induced Corneal Injury

研究项目 II - 起泡剂引起的角膜损伤

• 批准号: 10291227
• 负责人: MARION K GORDON
• 金额: $ 47.29万
• 依托单位: RBHS-SCHOOL OF PUBLIC HEALTH
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10291227
• 关键词: Advanced Development; Basement membrane; Blindness; Cells; Chronic Disease; Collagen; Collagen Type XVII; Cornea; Corneal Injury; Cyclophilin A; Cyclosporine; Deposition; Doctor of Philosophy; Doxycycline; Drug usage; Dry Eye Syndromes; Emulsions; Endopeptidases; Epithelial; Epithelial Attachment; Epithelial Cells; Excision; Exposure to; Extracellular Matrix; Extracellular Space; Eye; FDA approved; Fibronectins; Fibrosis; Gelatinase B; Glycoproteins; Grant; Human; Immunosuppressive Agents; Impaired healing; Impaired wound healing; Individual; Injury; Integrin alpha6beta4; Lead; Lesion; Ligands; Lipid Peroxidation; MMP9 gene; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Mechlorethamine; Mediating; Modeling; Mustard; Mustard Gas; Organ Culture Techniques; Oryctolagus cuniculus; Oxidants; Oxidative Stress; Oxytetracycline; Pathology; Peptide Hydrolases; Peptidylprolyl Isomerase; Pharmaceutical Preparations; Process; Production; Proteins; Research Personnel; Research Project Grants; Structure; TNF-alpha converting enzyme; Testing; Therapeutic; Therapeutic Intervention; Time; Tissues; Toxic effect; Universities; Up-Regulation; Vesicants; base; cell motility; cell type; corneal epithelium; corneal regeneration; epithelial injury; experimental study; eye dryness; hevin; meetings; nanomolar; response to injury; targeted treatment; vapor; wound; wound bed; wound healing

Research Project 2. Vesicant-induced Cornea Injury Project Lead: Marion K. Gordon, Ph.D. Co-Investigator: Laurie B. Joseph, Ph.D. Project Summary/Abstract Mustard vesicants including sulfur mustard (SM) and nitrogen mustard (NM) cause a range of debilitating injures to human eyes that can lead to long term pathologies and blindness. In previous studies we demonstrated that mustard injury is due in part to separation of the corneal epithelium from the stroma; moreover, this is a consequence of activation of proteases including matrix metalloproteinase (MMP)-9 and the endopeptidase, ADAM17, which degrade essential epithelial cell anchoring proteins. During the last grant period, we demonstrated that doxycycline, an inhibitor of MMPs, was effective in blunting the toxicity of both NM and SM in cultured corneas, and in a rabbit SM vapor model of corneal injury. Based on our findings, two pre-IND meetings were held with the FDA, and an ocular drug product, oxytetracycline, is currently moving towards advanced development. Expression of MMP9 and ADAM17 is induced by EMMPRIN (Extracellular Matrix Metalloproteinase Inducer, CD147), a transmembranous glycoprotein synthesized by epithelial cells. The ligand for EMMPRIN is cyclophilin A, which is released from cells in response to injury or oxidative stress. Following mustard exposure, we found that EMMPRIN is markedly upregulated in the cornea, suggesting a potential target for therapeutic intervention. The immunosuppressive agent cyclosporine A (CsA) has been shown to inhibit cyclophilin A activity at nanomolar concentrations. We discovered that Restasis®, a CsA emulsion, is effective in blocking epithelial detachment after exposure of the cornea to NM. Moreover, it reduced MMP9 expression in the cornea. These exciting findings suggest that Restasis® has potential to be developed as an ocular countermeasure against mustards. Based on these findings, we hypothesize that mustard induced oxidative stress in the cornea causes the release of cyclophilin A from corneal epithelial cells which upregulates EMMPRIN; this results in increases in proteases which cause epithelial-stromal separation; EMMPRIN also dysregulates expression of provisional matrix proteins (e.g., SPARC, hevin, fibronectin). As a consequence, there is delayed wound healing and persistent epithelial injury which ultimately leads to chronic disease. To test this hypothesis, plans are to: (1) Analyze the effects of mustard vesicants on EMMPRIN expression in the cornea; (2) Assess the effects of mustard vesicants on deposition of provisional matrix molecules in the cornea; and (3) Determine whether blocking cyclophilin A-induced activation EMMPRIN suppresses mustard-induced corneal damage. Results of our studies will elucidate mechanisms mediating mustard vesicant-induced corneal injury which will lead to the identification of new efficacious therapeutics for mitigating toxicity.

研究项目2.糜烂性角膜损伤 项目负责人：Marion K.戈登博士 合作研究者：劳里B。约瑟夫博士 项目总结/摘要 芥子类起疱剂包括硫芥子气（SM）和氮芥子气（NM）， 对人眼的伤害，可能导致长期病变和失明。在以前的研究中， 证明芥子气损伤部分是由于角膜上皮与基质分离; 此外，这是包括基质金属蛋白酶（MMP）-9和蛋白酶的蛋白酶活化的结果。 内肽酶，ADAM 17，其降解必需的上皮细胞锚定蛋白。在上一次赠款期间 在此期间，我们证明了多西环素，一种MMPs的抑制剂，可以有效地减弱这两种药物的毒性。 NM和SM在培养的角膜中，以及在角膜损伤的兔SM蒸汽模型中。根据我们的发现，两个 与FDA举行了IND前会议，一种眼用药物产品土霉素目前正在 走向先进发展。MMP 9和ADAM 17的表达由EMMPRIN（细胞外基质）诱导。 基质金属蛋白酶诱导剂，CD 147），一种由上皮细胞合成的跨膜糖蛋白。 EMMPRIN的配体是亲环素A，其响应于损伤或氧化应激而从细胞释放。 在芥子气暴露后，我们发现EMMPRIN在角膜中显著上调，这表明在角膜中， 治疗干预的潜在目标。免疫抑制剂环孢菌素A（CsA）已被 显示在纳摩尔浓度下抑制亲环素A活性。我们发现Restasis®，一种CsA， 在角膜暴露于NM后，乳剂有效阻断上皮脱落。而且 降低角膜中MMP 9的表达。这些令人兴奋的发现表明，Restasis®有潜力成为 作为一种视觉上的对抗措施而发展起来的。基于这些发现，我们假设， 芥子气诱导的角膜氧化应激导致角膜上皮细胞释放亲环素A 其上调EMMPRIN;这导致引起上皮-基质分离的蛋白酶增加; EMMPRIN还失调临时基质蛋白的表达（例如，Hevin，Fibronectin）。作为 因此，存在延迟的伤口愈合和持续的上皮损伤，这最终导致慢性炎症。 疾病为了验证这一假设，计划：（1）分析芥子疱剂对EMMPRIN的影响 （2）评估芥子类发泡剂对临时基质沉积的影响 确定是否阻断亲环素A诱导的EMMPRIN活化 抑制芥末引起的角膜损伤我们的研究结果将阐明介导 芥子气引起的角膜损伤，这将导致新的有效治疗方法的鉴定， 减轻毒性。