Oxidized lipids and microvesicle particles as effectors for chemical threats to skin

氧化脂质和微泡颗粒作为皮肤化学威胁的效应器

• 批准号: 10648739
• 负责人: Ravi PRAKASH Sahu
• 金额: $ 18.75万
• 依托单位: WRIGHT STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-10 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10648739
• 关键词: Address; Agonist; Alkylating Agents; Antidotes; Antineoplastic Agents; Antioxidants; Applications Grants; Arsenic; Arsenicals; Binding; Burn injury; Cell Line; Cells; Chemical Warfare; Chemicals; Cisplatin; Coupled; Cutaneous; Cytoplasm; Dacarbazine; Development; Dose; Enzymes; Epithelial Cells; Ethanol; Etoposide; Exposure to; Functional disorder; Generations; Genetic; Goals; Human; Immunosuppression; In Vitro; Inflammation; Inflammatory Response; Injury; Ionizing radiation; Knockout Mice; Knowledge; Laboratories; Mechlorethamine; Mediating; Melphalan; Membrane; Modeling; Molecular; Morbidity - disease rate; Mus; Mustard Gas; Nitrogen; Nuclear; Null Lymphocytes; Organ; Outcome; Oxides; PUVA Photochemotherapy; Pathology; Pathway interactions; Pilot Projects; Platelet Activating Factor; Platelet Inhibitors; Pre-Clinical Model; Process; Production; Reactive Oxygen Species; Receptor Signaling; Role; Signal Pathway; Signal Transduction; Site; Skin; Skin injury; Stimulus; Techniques; Testing; Therapeutic; Tissues; Toxic effect; Toxicant exposure; Translating; Travel; UVB induced; Ultraviolet B Radiation; Vesicants; Vesicle; acid sphingomyelinase; antagonist; body system; cell injury; chemical threat; chemotherapeutic agent; chemotherapy; cigarette smoke; cytokine; cytotoxic; gemcitabine; genetic approach; in vivo; inhibitor; insight; keratinocyte; lipid mediator; microvesicles; mortality; mouse model; novel; novel strategies; oxidized lipid; particle; pharmacologic; platelet activating factor receptor; prevent; response; stressor; systemic toxicity; tool; toxicant; transmission process; ultraviolet

Abstract The threats to chemical warfare-associated agents, including arsenicals and nitrogen mustards are increasing exceedingly, and no direct antidote is currently available to mitigate the deleterious cutaneous and systemic responses to prevent mortality. Though the associated cytotoxic effects of most of these agents are mediated due to their ability to act as alkylating agents, a significant knowledge gap exits in the understanding of detailed molecular mechanisms of how these vesicants cause cutaneous and systemic toxic effects, and thus, the development of antidotes. The current proposal is built upon the scientific premise that exposure to various pro- oxidative stressors, including alkylating chemotherapeutic agents, and thermal burn injuries (TBI) when coupled with ethanol (ETOH) produce the potent bioactive lipid mediator, Platelet-activating factor (PAF) by both enzymatically and non-enzymatically via reactive oxygen species (ROS). Studies, including ours, have shown that these PAF agonists induce local inflammation, as well as multi-system organ dysfunction (MOD). Importantly, recent studies have indicated that small membrane-bound vesicles known as microvesicle particles (MVP), generated via acid sphingomyelinase (aSMase) enzyme, are released from cells in response to various stressors. These MVP can act as potent signaling agents due to their ability to carry nuclear and cytoplasmic components. More importantly, the current proposal is built upon our discovery that chemotherapeutic agents, and TBI+ETOH via their ability to damage keratinocytes, generate PAF agonists which travel via MVP to induce the local (cutaneous) and systemic responses. Using antioxidants and PAFR-expressing/null cell lines and pharmacologic/genetic inhibition of aSMase enzyme, our studies have implicated the involvement of the PAFR signaling in aSMase activation resulting in PAF-laden MVP release. Based upon these compelling evidences, we hypothesize that chemical warfare-associated agents via their ability to generate ROS, produce PAF agonists and MVP from human and murine keratinocytes in a PAFR-aSMase-dependent manner, which mediate the cutaneous cytotoxic as well as systemic MOD effects. Two aims are proposed to test our hypothesis. Aim 1 will use validated in vitro and ex vivo models and pharmacologic agents to determine the roles of the PAFR, downstream signaling pathways, and aSMase enzyme in chemical warfare-associated agents-induce PAF agonists and MVP generation. Agents to be tested are nitrogen/sulfur mustards and an arsenical. Aim 2 will use PAFR/aSMase-expressing and deficient mouse models, as well as pharmacological inhibitors of PAFR and aSMase to determine the role of PAF-laden MVP generation in the local and systemic responses by topical nitrogen mustargen exposure. Successful completion of this project will (i) fill important mechanistic gaps in and validate novel tools to allow the modulation of PAF-laden MVP generation to mitigate chemical warfare- associated agents’ effects; and ii) address functional roles of PAFR-aSMase in nitrogen mustard-induced local and systemic MOD effects, to provide novel treatment approaches.

摘要 对化学战相关毒剂的威胁正在增加，包括军火库和含氮芥末。 非常严重，而且目前还没有直接的解毒剂来减轻有害的皮肤和全身 预防死亡的应对措施。尽管大多数这些药物的相关细胞毒作用是通过 由于它们作为烷基化试剂的能力，在理解细节方面存在显著的知识差距 这些发泡剂如何引起皮肤和全身毒性影响的分子机制，因此， 解毒剂的开发。目前的建议是建立在科学前提下的，即接触各种亲- 氧化应激源，包括烷化化疗药物，与热烧伤(TBI)相结合 用乙醇(Etoh)产生有效的生物活性脂质介体--血小板激活因子(PAF) 酶促和非酶促通过活性氧自由基(ROS)。包括我们在内的研究表明， 这些PAF激动剂导致局部炎症，以及多系统器官功能障碍(MOD)。 重要的是，最近的研究表明，与膜结合的小泡称为微泡颗粒 (MVP)是由酸性鞘磷脂酶(ASMase)产生的，在不同的条件下从细胞中释放出来。 压力源。这些MVP由于其携带细胞核和细胞质的能力，可以起到强有力的信号转导作用 组件。更重要的是，目前的建议是建立在我们发现化疗药物的基础上， TbI+Etoh通过损伤角质形成细胞，产生PAF激动剂，通过MVP传递诱导 局部(皮肤)和全身反应。使用抗氧化剂和PAFR表达/空细胞系和 ASMase酶的药理/遗传抑制，我们的研究表明PAFR参与其中 ASMase激活中的信号导致PAF-MVP的释放。基于这些令人信服的证据 我们假设，化学战相关药物通过它们产生RO的能力，产生PAF激动剂 和MVP以PAFR-aSMase依赖的方式从人和小鼠角质形成细胞中介导 皮肤细胞毒性以及全身性MOD效应。我们提出了两个目标来检验我们的假设。目标1将 使用有效的体外和体外模型和药理学药物来确定PAFR的作用， 化学战相关药物中的下游信号通路和aSMase酶--诱发PAF 激动剂和MVP的产生。被测试的试剂是氮/硫芥末和一种砷。AIM 2将使用 PAFR/aSMase表达和缺陷小鼠模型，以及PAFR和aSMase的药理抑制剂 ASMase确定PAF-MVP生成在局部和全身局部反应中的作用 暴露在氮气中。这一项目的成功完成将(I)填补重要的机制空白 验证允许调制富含PAF的MVP生成以缓解化学战的新工具- 联合制剂的作用；以及ii)PAFR-aSMase在氮芥末诱导的局部区域中的功能作用 和全身性MOD效应，提供新的治疗方法。