Modulation of Inflammation and Oxidative Stress in Diabetic Wound Healing

项目摘要/摘要：糖尿病创面愈合障碍是一个主要的临床问题。 这一问题导致了长时间的住院和巨额的医疗支出。三分之二的非- 创伤性截肢之前会有糖尿病伤口。糖尿病伤口愈合受阻的原因是 然而，越来越多的证据表明，持续的炎症对 糖尿病创面的发病机制是通过持续激活炎症通路而增加的 氧化应激。我们已经证明糖尿病创面增加了促炎因子的表达。 细胞因子IL-6和IL-8，以及抗炎microRNA-146a的表达减少，从而抑制 NFkB活化及下游IL-6、IL-8基因表达。在正常的伤口愈合中，巨噬细胞 最初两极分化为促炎性M1表型，然后过渡到M2表型，即 与炎症的消退和伤口的愈合有关。慢性炎症与相关的ROS 促进持续的促炎性M1巨噬细胞极化和未能过渡到M2 表型，这与慢性糖尿病创面的发展有关。我们设计了 具有清除ROS性能并将其偶联的新型氧化铈纳米颗粒(CNP) 使用miR-146a模拟物，协同靶向促炎信号和ROS。在令人信服的 初步数据，我们发现用我们的新型miR-146a一次性治疗小鼠糖尿病伤口 共轭CNP(CNP-miR146a)可促进糖尿病创面愈合，与非糖尿病创面相似 在第7天，这与炎症减轻和NOX2表达减少有关。在……里面 更多的初步数据表明，CNP-miR146a也可以促进创面愈合。 链脲佐菌素猪糖尿病模型。这项工作的目标是确定 CNP-miR146a纠正糖尿病创面愈合损害，并在 临床前猪模型。我们假设CNP-miR146a将减少炎症和氧化应激， 从而推动巨噬细胞从促炎(M1)表型向抗炎(M2)表型转变 可消除慢性炎症反应，促进愈合。 具体目标1：测试CNP-miR146a是否通过以下方式纠正糖尿病创面愈合损害 减少炎症和氧化应激。 特定目标2：测试CNP-miR146a是否能减轻炎症和氧化应激 治疗通过减少促炎症(M1)和增加抗炎来促进愈合 炎症/溶解(M2)巨噬细胞极化。 特异性目标3：验证microRNA-146a偶联CNPs对糖尿病创面愈合的纠正作用 在临床前猪模型中，该药对人体有损害，且无毒。

PROJECT SUMMARY/ABSTRACT: The diabetic wound healing impairment represents a major clinical problem, resulting in prolonged hospitalizations and significant healthcare expenditures. Two-thirds of non- traumatic amputations are preceded by a diabetic wound. The impaired healing of diabetic wounds has been shown to be multifactorial, however, increasing evidence suggests that persistent inflammation contributes to the pathogenesis of diabetic wounds through persistent activation of inflammatory pathways and increased oxidative stress. We have shown that diabetic wounds have increased expression of the proinflammatory cytokines IL-6 and IL-8, and decreased expression of the anti-inflammatory microRNA-146a, which inhibits NFkB activation and downstream IL-6 and IL-8 gene expression. In normal wound healing, macrophages are initially polarized to the proinflammatory M1 phenotype and then transition to the M2 phenotype, which is associated with resolution of inflammation and wound closure. Chronic inflammation and the associated ROS promote persistent proinflammatory M1 macrophage polarization and a failure to transition to the M2 phenotype, which has been implicated in the development of chronic diabetic wounds. We have designed novel cerium oxide nanoparticles (CNPs) that possess ROS scavenging properties and have conjugated them with a miR-146a mimetic, to synergistically target both proinflammatory signaling and ROS. In compelling preliminary data, we have found that one-time treatment of murine diabetic wounds with our novel miR-146a conjugated CNPs (CNP-miR146a) can improve diabetic wound healing, similar to that of non-diabetic wounds at 7 days, and this is associated with decreased inflammation and decreased expression of NOX2. In additional preliminary data, we have shown that CNP-miR146a can also improve wound healing in a streptozotocin porcine diabetes model. The objective of this work is to determine the mechanisms by which CNP-miR146a corrects the diabetic wound healing impairment, and validate this correction and toxicity in a preclinical porcine model. We hypothesize that CNP-miR146a will reduce inflammation and oxidative stress, thus driving macrophage transition from a proinflammatory (M1) to an anti-inflammatory (M2) phenotype and allow for resolution of the chronic inflammatory response and result in enhanced healing. Specific aim 1: To test whether CNP-miR146a corrects the diabetic wound healing impairment by decreasing inflammation and oxidative stress. Specific aim 2: To test whether decreased inflammation and oxidative stress with CNP-miR146a treatment improves healing by decreased proinflammatory (M1) and increased anti- inflammatory/resolving (M2) macrophage polarization. Specific aim 3: To validate that microRNA-146a conjugated CNPs correct the diabetic wound healing impairment and is non-toxic in a preclinical porcine model.