Redox Control of Wound Healing

伤口愈合的氧化还原控制

• 批准号: 6913671
• 负责人: Chandan K Sen
• 金额: $ 27.66万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6913671
• 关键词: NAD(P)H dehydrogenase; angiogenesis; antisense nucleic acid; biological signal transduction; confocal scanning microscopy; electrochemistry; electron spin resonance spectroscopy; enzyme activity; focal adhesion kinase; gene environment interaction; gene expression; genetically modified animals; growth factor receptors; immunocytochemistry; immunoprecipitation; laboratory mouse; microarray technology; oxidation reduction reaction; tissue /cell culture; transfection; vascular endothelial growth factors; vascular endothelium; wound healing

DESCRIPTION (provided by applicant): Compromised wound tissue oxygenation has been long recognized as a key limiting factor in healing. Oxygen homeostasis has therefore been the center of major attention in wound healing research. Current findings indicate that a significant fraction of oxygen at the wound site is utilized to generate reactive oxygen species (ROS). ROS are classically described as accidental metabolic by-products, and are generally thought to be deleterious. The phagocyte NADPH oxidase deliberately generates ROS in transient bursts to kill pathogens. High concentrations of H2O2 (equal to or more than 1%) are used clinically for wound disinfection. However, there is a general agreement that at these doses H2O2 is harsh to regenerating cells and may not benefit overall healing. The recent discovery of another family of NADPH oxidases, the Nox/Duox family, provides additional examples of deliberate generation of ROS by non-phagocytic cells at the wound site. Upon induction, these cells generate low-levels of ROS on a sustained basis. Recent data support that such low concentration of ROS can regulate specific key redox-sensitive signaling processes most of which can be directly linked to wound healing. This proposal rests on our striking observation that genetic as well as pharmacological approaches to deliver low concentrations of ROS promote dermal wound angiogenesis, contraction and closure. Such low concentrations of ROS did not influence wound infection status. Strategies to decompose ROS at the wound site impaired healing. Taken together, these observations led to the hypothesis that resisting infection is not the sole role of ROS at the wound-site, and that ROS drives redox-signaling to support healing. Indeed, congenital defect in human NADPH oxidase results in impaired wound healing and antibiotics alone cannot correct such defect. We have observed that NADPH oxidase deficient transgenic mice suffer from impaired dermal healing even under infection-free conditions; the impairment is corrected by low-dose ROS delivery. Our working hypothesis is that ROS generated by wound-related cells (low-ROS by Nox; and residual ROS in the aftermath of phagocyte respiratory burst) support earlyphase acute wound healing by inducing redox-sensitive signal transduction pathways. Our long-term objective is to understand this new aspect of wound tissue oxygen homeostasis. We seek to illuminate the significance of redoxsensitive processes in wound healing, and to design redox-based strategies to promote healing. To test the stated hypothesis we propose the following three specific aims using standard models of murine acute dermal wound and in vitro culture of dermal microvascular endothelial cells: Aim 1. Investigate the role of ROS in excisional dermal wound vascularization, contraction and repair; Aim 2. Determine the significance of NADPH oxidases at the wound site; and Aim 3. Characterize the redox-sensitive mechanisms that regulate wound angiogenesis.

描述（由申请人提供）： 长期以来，受损的伤口组织氧合被认为是愈合的关键限制因素。因此，氧气稳态一直是伤口愈合研究中主要关注的中心。当前的发现表明，伤口部位的氧气很大一部分用于产生活性氧（ROS）。 ROS经典地描述为偶然的代谢副产品，通常被认为是有害的。吞噬细胞NADPH氧化酶故意在瞬态爆发中产生ROS以杀死病原体。高浓度的H2O2（等于或大于1％）在临床上用于伤口消毒。但是，人们普遍同意，在这些剂量下，H2O2对再生细胞是苛刻的，可能不会使整体愈合受益。最近发现另一个NADPH氧化酶NOX/DUOX家族的家族为伤口部位的非斑点细胞故意生成ROS的其他例子。诱导后，这些细胞会持续产生ROS的低水平。最近的数据支持，这种低浓度的ROS可以调节特定的氧化还原敏感的信号传导过程，其中大多数可以直接与伤口愈合有关。该提议取决于我们的惊人观察，即遗传和药理方法可提供低浓度的ROS促进皮肤伤口的血管生成，收缩和闭合。如此低浓度的ROS不会影响伤口感染状况。在伤口部位分解ROS的策略会损害愈合。综上所述，这些观察结果导致了以下假设：抵抗感染并不是ROS在伤口部位的唯一作用，并且ROS驱动氧化还原信号以支持愈合。实际上，人NADPH氧化酶的先天性缺陷会导致伤口愈合受损，仅抗生素无法纠正这种缺陷。我们已经观察到NADPH氧化酶缺乏的转基因小鼠即使在无感染条件下也患有皮肤愈合受损。低剂量ROS递送纠正损伤。我们的工作假设是，与伤口相关的细胞产生的ROS（NOX低ROS；在吞噬细胞呼吸道爆发后的残留ROS）通过诱导氧化还原敏感的信号转导途径来支持早期急性伤口愈合。我们的长期目标是了解伤口组织氧稳态的新方面。我们试图阐明氧化还原敏感过程在伤口愈合中的重要性，并设计基于氧化还原的策略以促进愈合。为了检验既定假设，我们提出了以下三个特定目的，使用鼠急性皮肤伤口和皮肤微血管内皮细胞的体外培养的标准模型：目标1。 AIM 2。确定伤口部位的NADPH氧化酶的重要性；目标3。表征调节伤口血管生成的氧化还原敏感机制。