DAMP-RAGE Signaling and Fetal Injury in Inflammation-Induced Preterm Birth

项目摘要/摘要 宫内和/或胎儿炎症、早产和不良反应的发生率之间存在很强的相关性。 新生儿结局，包括脑瘫。如果要制定有针对性的干预措施以改善结果 我们需要充分了解无意中导致胎儿细胞和组织损伤的分子机制。 受伤。损伤相关分子模式分子(DAMP)是细胞内的一组多效性分子。 包括高迁移率族蛋白1(HMGB1)和S100钙结合成员的蛋白质 蛋白质家族(即S100A12、S100A8、S100B)。当被释放到细胞外隔室时 对于炎症或氧化应激，湿气通过激活内源性受体，如 作为晚期糖基化终产物(RAGE)的受体。愤怒的参与导致细胞 氧化应激和核因子-kappaB的持续活性导致的功能障碍和损伤。vbl.使用 蛋白质组学研究发现S100A12在协调羊膜内炎性反应中起关键作用 通过激活RAGE对感染作出反应。我们还表明，人类胎儿具有高度的 炎症状态会增加HMGB1和S100B等原型阻尼剂的全身水平。在……里面 此外，在内毒素引起的胎儿损伤的小鼠模型中，我们证明了母体炎症是 与胎儿氧化应激和细胞内抗氧化剂谷胱甘肽的耗竭有关。在相同的 实验模型进一步提供了HMGB1和RAGE在肝脏和肝组织中过度表达的证据 宫内暴露于炎症中的胎儿的大脑。这一知识体系，与证据相印证 HMGB1和S100蛋白是可能的RAGE配体，这使得我们提出了DAMP-1的积极作用。 RAGE轴在羊膜内感染和早产环境中诱发产前终末器官损害的作用 为了验证这一假设，将追求三个目标：1)特定目标1旨在提供活体观察 有证据表明宫内炎症会导致人类胎儿氧化还原动态平衡的失衡， 通过RAGE激活引起潮湿蛋白的释放和产前胎儿细胞损伤；2)特定目标 2我们将在体外探索原型DAMPS和RAGE信号的机制和功能作用。 在相关的生物检测中诱导细胞损伤。我们将测试抗HMGB1和抗RAGE阻断的效果 抗体或潜在的治疗剂，如N-乙酰半胱氨酸和丙酮酸乙酯，以逆转 阻尼轴激活的损伤效应；3)特定的目标3，通过使用独特的遗传 经过改造的RAGE缺陷(RAGE-/-)和RAGE转基因(RAGETg)动物，我们计划提供洞察力 探讨RAGE信号作为导致胎儿损伤的常见和强制性途径的价值 湿怒拮抗为体内治疗策略。通过实现这些目标，我们希望提供 对导致早产儿终末器官损害的过程的新见解并确定新的类别 可以调节胎儿炎症反应并改善结局的分子靶点。

PROJECT SUMMARY /ABSTRACT Strong correlations exist between intra-uterine and/or fetal inflammation, prematurity and incidence of adverse neonatal outcomes, including cerebral palsy. If targeted interventions to improve outcome are to be developed we need to fully understand the molecular mechanisms which inadvertently cause fetal cell damage and tissue injury. Damage-associated molecular pattern molecules (DAMPs) are a pleiotropic group of intra-cellular proteins including high-mobility group box 1 protein (HMGB1) and members of the S100 calcium binding protein family (i.e., S100 A12, S100A8, S100B). When released into the extra-cellular compartment as a result of inflammation or oxidative stress, DAMPs become "danger signals" by activating endogenous receptors such as the receptor of advanced glycation end-products (RAGE). Engagement of RAGE leads to cellular dysfunction and injury driven by oxidative stress and sustained activity of nuclear factor-kappa B (NF¿B). Using proteomics we discovered that S100A12 plays a key role in orchestrating the intra-amniotic inflammatory response to infection via RAGE activation. We have also shown that human fetuses with heightened inflammatory statuses have increased systemic levels of prototype DAMPs such as HMGB1 and S100B. In addition, in a mouse model of endotoxin induced fetal damage we demonstrated that maternal inflammation is associated with fetal oxidative stress and depletion of the intracellular antioxidant glutathione. In the same experimental model we further provided evidence that HMGB1 and RAGE and over-expressed in the liver and brain of the fetuses exposed to inflammation in utero. This body of knowledge, corroborated with the evidence that HMGB1 and S100 proteins are putative RAGE ligands, has led us to propose an active role for the DAMP- RAGE axis in inducing antenatal end-organ damage in the setting of intra-amniotic infection and prematurity. To test this hypothesis, three aims will be pursued: 1) Specific Aim 1 is geared to provide in vivo observational evidence that intra-uterine inflammation induces an imbalance in the redox homeostasis of the human fetus, causing release of DAMP proteins and antenatal fetal cellular damage via RAGE activation; 2) In Specific Aim 2 we will explore, in vitro, the mechanism and functional role of prototypical DAMPs and RAGE signaling in inducing cellular injury in a relevant bioassay. We will test the efficacy of anti-HMGB1 and anti-RAGE blocking antibodies or potential therapeutic agents such as N-acetylcysteine and ethyl pyruvate to reverse the damaging effects of the DAMP-RAGE axis activation; 3) In Specific Aim 3, by using unique genetically engineered RAGE deficient (RAGE-/-) and RAGE transgenic (RAGETg+) animals, we plan to provide insight into RAGE signaling as the common and obligatory pathway leading to fetal damage and explore the value of DAMP and RAGE antagonism as treatment strategies in vivo. By completing these aims we hope to provide novel insight into the processes leading to end-organ damage in premature infants and identify new classes of molecular targets that can modulate the inflammatory response of the fetus and improve outcomes.