GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENCY AND SEPSIS

6-磷酸葡萄糖脱氢酶缺乏症和脓毒症

• 批准号: 6628867
• 负责人: ZOLTAN SPOLARICS
• 金额: $ 31.79万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6628867
• 关键词: African American; adult human (21+); apoptosis; bacterial disease; blood tests; blood toxicology; cell cell interaction; cord blood; cytokine; disease /disorder proneness /risk; gene expression; genetic polymorphism; glucose 6 phosphate dehydrogenase deficiency; hemolysis; human subject; inflammation; laboratory rat; male; molecular pathology; multiple organ failure; oxidative stress; patient oriented research; phagocytes; reticuloendothelial system; tissue /cell culture; trauma

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human genetic polymorphism. A clinically significant variant is the type A deficiency present in 10-12% of African Americans. G6PD is a major supporter of cellular redox status. Our clinical investigations on young African American trauma patients revealed that after severe trauma, the type A- G6PD deficiency predisposes to the development of bacteremic sepsis, an augmented inflammatory response and worsens anemia. The defect also alters the trauma-induced monocyte responses. We will investigate the impact of the defect on the sepsis-associated multiple organ dysfunction/failure and mortality after major trauma. We will test if a compromised RBC function and an altered activation status of the reticolo-endothelial/monoculear phagocyte system contribute to the adverse clinical effects of the deficiency. The study use G6PD deficient and nondeficient human endothelial cells (HUVEC), monocytes and neutrophils and an animal model. Hypotheses: 1: After severe trauma, the sepsis-associated mortality is greater in G6PD deficient patients than non-deficient patients. The adverse clinical course of G6PD deficient patients is associated with a diminished production of anti- inflammatory cytokines by monocytes, increased hemolysis, and decreased RBC deformability. The prospective cohort study will compare the clinical parameters in G6PD deficient and nondeficient patients after major trauma (ISS>13) and the time dependent changes in cytokine patterns representative of the proinflammatory/anti-inflammatory balance in leukocytes. Alterations in RBC deformability, lipid peroxidation, nitrosylated protein, nitroso-thiol and glutathione content will also be followed. 2: After oxidative stress, G6PD deficient endothelial cells and monocytes display an augmented pro-inflammatory response compared to non-deficient cells. Activation of redox-dependent transcription factors ( NFkB,AP1,SP1) and redox status (GSH/GSSG) and the accompanying changes in cytokine production will be determined after ischemia- reoxygenation or chemically-induced oxidative stress in deficient and non-deficient HUVEC and monocytes. 3. G6PD deficiency diminishes the antioxidant capacity of endothelial cells more severely than the antioxidant capacity of phagocytes which results in an enhanced phagocyte-mediated endothelial dysfunction. Phagocyte-mediated endothelial cell apoptosis/injury will be measured in co-cultures using deficient or non-deficient cells. Using specific inhibitors of G6PD in an animal model will test endothelial cell dysfunction. The studies will elucidate if the adverse clinical effects of G6PD deficiency are manifested in elevated mortality and worsening organ dysfunction after injuries. The study will reveal important and novel information on the potential mechanisms, including RBC dysfunction, monocyte activation, and the role of redox regulated gene expression that is responsible for the adverse clinical effects of G6PD deficiency in trauma patients.

葡萄糖-6-磷酸脱氢酶（G6 PD）缺乏症是人类最常见的遗传多态性。一个临床上显著的变异是A型缺乏症，存在于10-12%的非洲裔美国人中。G6 PD是细胞氧化还原状态的主要支持者。我们对年轻的非洲裔美国人创伤患者的临床研究表明，严重创伤后，A-G6 PD缺乏症易导致菌血症性脓毒症、炎症反应增强和Alzheimer贫血的发生。该缺陷还改变了创伤诱导的单核细胞反应。我们将研究该缺陷对严重创伤后脓毒症相关多器官功能障碍/衰竭和死亡率的影响。我们将检测红细胞功能受损和网状内皮细胞/单核细胞吞噬细胞系统活化状态改变是否会导致该缺陷的不良临床效应。本研究使用G6 PD缺陷型和非缺陷型人内皮细胞（HUVEC）、单核细胞和中性粒细胞以及动物模型。假设：1：严重创伤后，G6 PD缺陷患者的脓毒症相关死亡率高于非缺陷患者。G6 PD缺陷患者的不良临床病程与单核细胞产生的抗炎细胞因子减少、溶血增加和红细胞变形能力降低有关。前瞻性队列研究将比较严重创伤（ISS>13）后G6 PD缺陷和非缺陷患者的临床参数以及代表白细胞中促炎/抗炎平衡的细胞因子模式的时间依赖性变化。还将跟踪RBC变形性、脂质过氧化、亚硝基化蛋白、亚硝基硫醇和谷胱甘肽含量的变化。第二章：氧化应激后，G6 PD缺陷的内皮细胞和单核细胞显示增强的促炎反应相比，非缺陷细胞。在缺血-再氧合或化学诱导的氧化应激后，在缺陷型和非缺陷型HUVEC和单核细胞中测定氧化还原依赖性转录因子（NFkB、AP 1、SP 1）和氧化还原状态（GSH/GSSG）的活化以及伴随的细胞因子产生的变化。3. G6 PD缺乏降低内皮细胞的抗氧化能力比吞噬细胞的抗氧化能力更严重，这导致增强的吞噬细胞介导的内皮功能障碍。将在使用缺陷或非缺陷细胞的共培养物中测量吞噬细胞介导的内皮细胞凋亡/损伤。在动物模型中使用G6 PD的特异性抑制剂将测试内皮细胞功能障碍。这些研究将阐明G6 PD缺乏症的不良临床影响是否表现为损伤后死亡率升高和器官功能障碍恶化。该研究将揭示有关潜在机制的重要和新颖信息，包括RBC功能障碍，单核细胞活化以及氧化还原调节基因表达的作用，这些基因表达是创伤患者G6 PD缺乏症的不良临床影响的原因。