Epigenetic Regulation of Prostaglandin E2 (PGE2) Synthesis Alters Macrophage Function to Promote Inflammation and Impair Diabetic Wound Healing

前列腺素 E2 (PGE2) 合成的表观遗传调控改变巨噬细胞功能，促进炎症并损害糖尿病伤口愈合

• 批准号: 10374885
• 负责人: Katherine Ann Gallagher
• 金额: $ 45.05万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10374885
• 关键词: Amputation; Arachidonate 5-Lipoxygenase; Arachidonic Acids; Bacterial Infections; Blood specimen; Cells; Chronic; Complement Factor B; Complications of Diabetes Mellitus; Cyclooxygenase Inhibitors; Cytosolic Phospholipase A2; DNA Methylation; DNA Modification Methylases; Data; Defect; Diabetes Mellitus; Diabetic mouse; Diet; Dinoprostone; Epigenetic Process; FDA approved; Failure; Fibroblasts; Functional disorder; Genes; Genetic; Genetic Models; Grant; Homeostasis; Host Defense; Human; Impaired wound healing; Impairment; In Vitro; Infection; Inflammation; Inflammation Mediators; Inflammatory; Interleukin-1 beta; Leukotrienes; Link; Lipids; MLL gene; Malignant Neoplasms; Mediating; Methods; Methylation; Molecular; Morbidity - disease rate; Mus; Non-Insulin-Dependent Diabetes Mellitus; PTGS2 gene; Pathway interactions; Patients; Phagocytosis; Pharmacology; Phenotype; Predisposition; Production; Prostaglandin Inhibition; Prostaglandin Production; Prostaglandin-Endoperoxide Synthase; Prostaglandins; Proteins; Publishing; Receptor Inhibition; Receptor Signaling; Regulation; Resolution; Role; Sampling; Signal Transduction; TNF gene; Testing; Therapeutic; Tissue Sample; Tissues; Transforming Growth Factor beta; Transforming Growth Factors; Treatment Efficacy; Up-Regulation; acute wound; antagonist; base; chronic wound; cyclooxygenase 2; db/db mouse; diabetic; diabetic patient; diabetic ulcer; diabetic wound healing; diet-induced obesity; dietary; epigenetic regulation; experimental study; healing; histone methylation; histone methyltransferase; immunoregulation; improved; in vivo; inhibitor; macrophage; monocyte; mortality; mouse model; non-healing wounds; novel; novel therapeutics; overexpression; particle therapy; pathogen; pathogenic bacteria; prevent; receptor; targeted delivery; targeted treatment; therapeutic target; tissue repair; wound; wound bed; wound healing

PROJECT SUMMARY/ABSTRACT Non-healing wounds in patients with Type 2 Diabetes (T2D) are a major cause of morbidity and mortality and are increasing at an alarming rate. Failure of wound healing in T2D patients represents the most common cause of amputation in the US with a 5-year mortality rate of nearly 50%. Thus, a critical need exists for understanding the wound healing defects in T2D in order to develop targeted therapies. We have utilized both genetic (db/db) and dietary (diet-induced obese) murine models of T2D as well as human wound tissue and blood samples collected from T2D patients to explore mechanisms of impaired wound healing. Our published and preliminary data point to a pivotal role for macrophage (Mφ) function in orchestrating appropriate wound healing and demonstrate that wound Mφs in diabetic mice and patients with T2D are characterized by a persistent inflammatory state, impaired phagocytosis/killing and the over-production of the immunomodulatory lipid, prostaglandin E2 (PGE2). Our data demonstrate epigenetic regulation of key genes important for the production of PGE2, namely cytosolic phospholipase A2 (cPLA2) and cyclooxygenase-2 (COX-2), and show overexpression of PGE2 in Mφs results in increased production of inflammatory mediators such as interleukin 1β (IL1β) and impaired host defense against bacterial pathogens that often colonize the wound bed. Our preliminary data are the first to identify that cPLA2/COX-2 and PGE2 are increased in diabetic wound Mφs and that this pathway may be regulated by multiple epigenetic mechanisms, including DNA methylation and histone methylation, in both diet-induced and genetic models of diabetes. These results support our hypothesis that inhibition of the COX-2/PGE2 pathway in Mφs is critical for resolution of inflammation and proper host defense that is required for effective wound repair. These results have led to our hypothesis that the COX-2/PGE2 pathway is epigenetically regulated and increased in diabetic wound Mφs and this results in increased inflammation, impaired host defense and defective wound repair. Our data suggest that wound Mφ function may be restored via Mφ-targeted treatment of FDA-approved COX inhibitor(s), TGFβ signaling receptors and/or the first-ever developed EP2-specific antagonist. To test our hypotheses, we will: Aim 1: Determine the regulation of cPLA2 to release AA and promote COX-2/PGE2 production in diabetic wound Mφs. Aim 2: Determine whether TGFβ-induced miR-29b causes hypomethylation of the COX-2 gene to increase COX-2 and PGE2 production in diabetic wound Mφ and evaluate the therapeutic efficacy of Mφ targeted COX-2 inhibition and TGFβ receptor antagonists. Aim 3: Determine the Mφ-specific PGE2-mediated mechanism(s) that modulate inflammation, host-defense functions and fibroblast crosstalk in normal and diabetic wound tissue.

项目总结/摘要 2型糖尿病（T2 D）患者的不愈合伤口是发病率和死亡率的主要原因， 正以惊人的速度增长T2 D患者中伤口愈合失败是最常见的 在美国，这是截肢的原因，5年死亡率接近50%。因此，迫切需要 了解T2 D的伤口愈合缺陷，以开发靶向治疗。我们利用了两者 T2 D的遗传（db/db）和饮食（饮食诱导的肥胖）鼠模型以及人伤口组织， 从T2 D患者收集血液样品以探索受损伤口愈合的机制。我们的出版 初步数据表明，巨噬细胞（Mφ）功能在协调适当的伤口中发挥着关键作用， 并证明糖尿病小鼠和T2 D患者的伤口Mφ的特征在于 持续的炎症状态，受损的吞噬/杀伤和免疫调节因子的过度产生 脂质，前列腺素E2（PGE 2）。我们的数据表明，表观遗传调控的关键基因的重要性， 产生PGE 2，即胞质磷脂酶A2（cPLA 2）和环氧合酶-2（考克斯-2），并显示 PGE 2在Mφ中的过度表达导致炎性介质如白细胞介素 1β（IL 1 β）和受损的宿主对细菌病原体的防御，这些细菌病原体通常定植在伤口床上。我们 初步数据首次确定糖尿病伤口Mφ中cPLA 2/考克斯-2和PGE 2增加， 这一途径可能受到多种表观遗传机制的调控，包括DNA甲基化和组蛋白 甲基化，在饮食诱导的和遗传的糖尿病模型中。这些结果支持了我们的假设， 抑制Mφ中的考克斯-2/PGE 2通路对于炎症消退和适当的宿主防御是至关重要的 这是有效修复伤口所必需的这些结果导致我们假设考克斯-2/前列腺素E2 在糖尿病伤口Mφs中，M φ途径受到表观遗传学调节并增加，这导致M φ增加。 炎症、宿主防御受损和伤口修复缺陷。我们的数据表明，创伤Mφ功能 可通过FDA批准的考克斯抑制剂、TGFβ信号传导受体 和/或首次开发的EP 2特异性拮抗剂。为了验证我们的假设，我们将：目标1：确定 糖尿病创面Mφs中cPLA 2的调节释放AA和促进考克斯-2/PGE 2的产生。目标二： 确定TGFβ诱导的miR-29 b是否导致考克斯-2基因的低甲基化以增加考克斯-2 观察糖尿病创面Mφ分泌PGE 2的情况，评价Mφ靶向考克斯-2的治疗效果 抑制和TGFβ受体拮抗剂。目的3：确定Mφ特异性PGE 2介导的机制 其调节正常和糖尿病伤口中炎症、宿主防御功能和成纤维细胞串扰 组织.