Mechanistic targets for intervention in sepsis-induced renal injury

干预脓毒症肾损伤的机制目标

• 批准号: 7987557
• 负责人: Philip R. Mayeux
• 金额: $ 6.71万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7987557
• 关键词: 4 year old; Acute Renal Failure with Renal Papillary Necrosis; Address; Adult; Biochemical; Blood Vessels; Blood capillaries; Caspase; Cause of Death; Cell Culture Techniques; Cells; Child; Complication; Data; Defect; Disease; Endothelial Cells; Endothelium; Enzymes; Epithelial; Epithelial Cells; Epithelium; Event; Evolution; Functional disorder; Generations; Genetic; Hour; Immunohistochemistry; Impaired Renal Function; In Vitro; Injury; Intervention; Kidney; Kidney Failure; Knockout Mice; Ligation; Mediating; Mediator of activation protein; Modeling; Motion; Mus; Pathogenesis; Pathway interactions; Patients; Perfusion; Postoperative Period; Protein p53; Puncture procedure; Reactive Nitrogen Species; Reactive Oxygen Species; Relative (related person); Renal function; Research; Role; Scheme; Sepsis; Septicemia; Serum; Signal Pathway; Signal Transduction; Stimulus; Superoxide Dismutase; TP53 gene; Techniques; Testing; Tubular formation; Video Microscopy; base; capillary; caspase-3; cell injury; clinically relevant; cost; functional loss; human NOS2A protein; in vivo; inhibitor/antagonist; injured; mortality; new therapeutic target; novel; overexpression; prevent; public health relevance

DESCRIPTION (provided by applicant): Renal failure is a frequent complication of septicemia that contributes significantly to mortality, particularly in postoperative patients in the ICU. In the U.S. septicemia is the 12th leading cause of death in adults and the 9th leading cause of death in children 1-4 years of age. Current therapy is, for the most part, only supportive. Thus, the long-term objective of our research is to identify new therapeutic targets to treat sepsis-induced renal injury. In this proposal, we will describe a functional defect in the kidney that may represent a previously unrecognized vascular pathway involved in polymicrobial sepsis- induced renal injury using the most clinically relevant murine model, cecal ligation and puncture (CLP). Our preliminary data show that inhibition of inducible nitric oxide synthase, inhibition of caspases, or inhibition of p53 each can prevent CLP-induced renal failure in mice. We also discovered a dramatic loss in perfused cortical peritubular capillaries following CLP that is ameliorated by these three classes of inhibitors. This unexpected and novel finding of a CLP-induced vascular defect mediated by reactive nitrogen species (RNS), caspases, and p53 is the basis of our central hypothesis that in sepsis, RNS-initiated activation of caspases results in a decline in peritubular capillary perfusion that leads to RNS-dependent tubular epithelial injury and ultimately renal failure. We will use biochemical and intravital videomicroscopy techniques to assess peritubular capillary dysfunction and tubular injury following mild and severe CLP in mice. Aim 1 will determine if peritubular endothelial injury and capillary dysfunction are early events that precede tubule epithelial cell injury. Aim 2 will determine the relative contributions of caspase-3 and p53 in peritubular capillary dysfunction and tubule epithelial cell injury using both pharmacological and genetic approaches. Aim 3 will determine if RNS-induced activation of p53 and caspases contribute to CLP-induced peritubular capillary dysfunction and tubule epithelial cell injury using pharmacological a genetic approaches. Both Aim 2 and Aim 3 will use in vivo studies as well as complementary in vitro studies with primary cultures of renal endothelial and tubular epithelial cells. PUBLIC HEALTH RELEVANCE: These studies will supply valuable information on the cascade of signaling and cell- specific events that result in sepsis-induced renal injury. They will identify new signaling pathways and test them as new therapeutic targets for this devastating disease.

描述（由申请方提供）：肾衰竭是败血症的常见并发症，对死亡率有显著影响，尤其是在ICU的术后患者中。在美国，败血症是成人死亡的第12大原因，是1-4岁儿童死亡的第9大原因。目前的治疗在很大程度上只是支持性的。因此，我们研究的长期目标是确定新的治疗靶点来治疗脓毒症引起的肾损伤。在本提案中，我们将使用临床上最相关的小鼠模型盲肠结扎和穿刺（CLP）描述肾脏中的功能缺陷，其可能代表先前未被识别的涉及多微生物脓毒症诱导的肾损伤的血管通路。我们的初步数据表明，抑制诱导型一氧化氮合酶，抑制半胱天冬酶，或抑制p53的每一个可以防止CLP诱导的小鼠肾功能衰竭。我们还发现了一个显着的损失，灌流皮层管周毛细血管后，CLP，这是改善这三类抑制剂。CLP诱导的血管缺陷由活性氮物质（RNS）、半胱天冬酶和p53介导，这一意外和新颖的发现是我们中心假设的基础，即在脓毒症中，RNS启动的半胱天冬酶激活导致肾小管周围毛细血管灌注下降，导致RNS依赖性肾小管上皮损伤并最终导致肾衰竭。我们将使用生物化学和活体视频显微镜技术来评估小鼠轻度和重度CLP后肾小管周围毛细血管功能障碍和肾小管损伤。目的1将确定肾小管周围内皮损伤和毛细血管功能障碍是否是先于肾小管上皮细胞损伤的早期事件。目的2将使用药理学和遗传学方法确定caspase-3和p53在管周毛细血管功能障碍和小管上皮细胞损伤中的相对作用。目的3将使用药理学和遗传学方法来确定RNS诱导的p53和半胱天冬酶的激活是否有助于CLP诱导的小管周围毛细血管功能障碍和小管上皮细胞损伤。目标2和目标3均将使用肾内皮和肾小管上皮细胞原代培养物进行体内研究以及补充性体外研究。公共卫生关系：这些研究将提供关于导致脓毒症诱导的肾损伤的信号传导和细胞特异性事件级联的有价值的信息。他们将确定新的信号通路，并将其作为这种毁灭性疾病的新治疗靶点进行测试。