Treatment strategies for ocular toxicity from chloropicrin

项目摘要 氯化苦(三氯硝基甲烷，CP)，目前用作土壤熏蒸剂和杀虫剂，在#年使用。 第一次世界大战是催泪瓦斯和堵塞剂，并且仍然是化学恐怖主义的潜在毒剂。它的 暴露会造成严重的眼部损伤，特别是对角膜组织的损伤；然而，其损伤的机制是 没有明确定义和有效的靶向治疗是难以捉摸的。此应用程序的主要目标是标识一个 新的靶向治疗方法，可有效减轻CP所致的急性和长期眼损伤 暴露，有可能进一步测试其他有毒化学物质暴露造成的眼部损伤。 我们对角膜上皮细胞和体外兔角膜的研究数据表明， 核红系相关因子2(NRF2)和下游关键靶酶--血红素加氧酶-1(HO-1) Nrf2的表达，表明作为关键的抗氧化剂和细胞保护系统的Nrf2通路可能被激活 在暴露于CP之后。在这项申请下，我们建议进一步评估Nrf2途径在 用Nrf2基因敲除(KO)小鼠进行CP眼球损伤。NRF2活性触发细胞保护机制 抗氧化应激和炎症反应，据报道是新方法的关键靶点 治疗各种与氧化应激相关的眼部疾病/损伤。因此，使用NRF2激活剂可能是一种 治疗CP暴露所致眼损伤的新方法。眼部化学性损伤导致低氧 这会导致组织损伤；据报道，氧气疗法可以改善组织保存和加强伤口。 治愈以减轻眼睛的化学和热烧伤。我们的初步数据显示， 过饱和氧乳剂(SSOE)逆转CP急性毒性的实验研究 活体兔角膜。我们的假设是，Nrf2信号通路是保护病毒的关键媒介。 激活Nrf2通路可以抑制CP诱导的氧化应激，并 炎症，与SSOE同时治疗可以增加组织氧水平以改善组织 保存和促进伤口愈合，导致一种新的和更有效的治疗CP的策略- 导致急性和长期的眼部损伤。为了验证这一假设，提出的目标是：目标1。开发一种 建立环磷酰胺诱导的小鼠眼损伤模型，并确定Nrf2-ARE通路是否是环磷酰胺致眼损伤的关键介质。 用野生型和Nrf2KO小鼠诱导眼损伤。目的2.评价Nrf2激活剂和 单独或联合使用过饱和氧气乳剂，以确定有效的治疗策略 环磷酰胺致眼损伤。我们预计，上述目标的结果将建立一个有益的 CP致小鼠眼部损伤模型的建立及Nrf2信号通路是否是治疗的新靶点 抗CP眼外伤的治疗性干预。本项目圆满完成 将确定一种新的治疗方法，可以更有效地缓解急性和慢性眼病 这将有助于更好地理解CP致眼毒性的机制。

Project Summary Chloropicrin (Trichloronitromethane, CP), currently used as a soil fumigant and pesticide, was employed during World War I as a tear gas and choking agent and remains a potential agent for chemical terrorism. Its exposure causes severe ocular injury, especially to the corneal tissue; however, mechanisms of its injury are not well-defined and effective targeted treatments are elusive. The major goal of this application is to identify a novel targeted therapeutic approach, which can effectively mitigate acute and long-term ocular injuries from CP exposure, with a potential to be further tested against ocular injuries from other toxic chemical exposures. Data from our studies in corneal epithelial cells and ex vivo rabbit cornea demonstrate increased levels of nuclear erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), a critical target enzyme downstream of Nrf2, suggesting that the Nrf2 pathway, a key antioxidant and cytoprotective system, could be activated following CP exposure. Under this application, we propose to further asses the role of the Nrf2 pathway under CP-induced ocular injury using Nrf2 knockout (KO) mice. Nrf2 activity triggers cellular protective mechanisms against oxidative stress and inflammatory responses and is reported as a key target of new approaches for treating various oxidative stress-related ocular diseases/injuries. Hence, employing Nrf2 activators may be a novel approach for the treatment of ocular injuries due to CP exposure. Chemical ocular injury causes hypoxia that leads to tissue damage; oxygen therapy is reported to improve tissue preservation and enhance wound healing to mitigate ocular chemical and thermal burns. Our preliminary data shows the therapeutic potential of supersaturated oxygen emulsion (SSOE) therapy in reversing CP-induced acute toxicity in HCE cells and ex vivo rabbit corneas. Our hypothesis is that the Nrf2 signaling pathway is a key mediator in protecting against CP-induced corneal injury; activation of the Nrf2 pathway can inhibit CP-induced oxidative stress and inflammation, and simultaneous treatment with SSOE can increase tissue oxygen levels to improve tissue preservation and enhance wound healing, leading to a novel and more effective treatment strategy against CP- induced acute and long-term ocular injury. To test this hypothesis, the proposed aims are: Aim 1. To develop a CP-induced ocular injury model in mice and determine if the Nrf2-ARE pathway is a key mediator in CP- induced ocular injury using wild type and Nrf2 KO mice. Aim 2. To evaluate the efficacy of Nrf2 activators and supersaturated oxygen emulsion alone, or in combination, to identify an effective therapeutic strategy against CP-induced ocular injury. We anticipate that the outcomes from the above aims will establish a useful mouse ocular injury model with CP and ascertain if the Nrf2 signaling pathway is a novel target for therapeutic intervention to counteract CP-induced ocular injury. Successful completion of this project will identify a novel therapeutic approach that can more effectively mitigate acute and chronic ocular injuries from CP and lead to a better understanding of the mechanisms of CP-induced ocular toxicity.