TGF-beta1 and Mitochondrial Dysfunction in LPS-Induced Renal Failure

LPS 诱导的肾衰竭中的 TGF-β1 和线粒体功能障碍

基本信息

批准号：
8526967
负责人：
L. Jay Stallons
金额：
$ 3.04万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-08-08 至 2014-02-09
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8526967
关键词：
ATP Synthesis Pathway Acute Renal Failure with Renal Papillary Necrosis Address Biogenesis Cell Death Cells Communication Creatinine Educational process of instructing Electron Transport Event Failure Fellowship Gene Expression Genetic Models Goals Grant Homeostasis Inflammatory Injection of therapeutic agent Injury Ischemia K-Series Research Career Programs Kidney Kidney Failure Lead Lipopolysaccharides Measures Mediating Microscopy Mitochondria Modeling Mus Organ Output Pathway interactions Pharmaceutical Preparations Phase Production Proteins Receptor Signaling Recovery Renal function Reperfusion Therapy Reporting Research Research Methodology Respiration Role Sepsis Serum Therapeutic Time Training Transforming Growth Factors Trauma Tubular formation Urine Writing career career development cell injury experience glomerular filtration human TGFB1 protein improved inhibitor/antagonist mitochondrial dysfunction public health relevance research study septic skills

ATP Synthesis Pathway Acute Renal Failure with Renal Papillary Necrosis Address Biogenesis Cell Death Cells Communication Creatinine Educational process of instructing Electron Transport Event Failure Fellowship Gene Expression Genetic Models Goals Grant Homeostasis Inflammatory Injection of therapeutic agent Injury Ischemia K-Series Research Career Programs Kidney Kidney Failure Lead Lipopolysaccharides Measures Mediating Microscopy Mitochondria Modeling Mus Organ Output Pathway interactions Pharmaceutical Preparations Phase Production Proteins Receptor Signaling Recovery Renal function Reperfusion Therapy Reporting Research Research Methodology Respiration Role Sepsis Serum Therapeutic Time Training Transforming Growth Factors Trauma Tubular formation Urine Writing career career development cell injury experience glomerular filtration human TGFB1 protein improved inhibitor/antagonist mitochondrial dysfunction public health relevance research study septic skills

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项目摘要

DESCRIPTION (provided by applicant): Cell injury and death induced by sepsis, ischemia/reperfusion (I/R), drugs, and trauma lead to failure of many organs, including the kidney. Mitochondrial dysfunction is a common consequence of these insults and a major mechanism of cell injury and death. While mitochondrial dysfunction occurs after AKI, the state and role of mitochondrial function during the injury and recovery phases of sepsis-induced AKI remain unclear. We recently examined renal and mitochondrial function over time in a lipopolysaccharide (LPS) model of sepsis in mice. Glomerular filtration was normal at 18 h but decreased (i.e. elevated serum creatinine) 42 h after LPS injection. Urine output was minimal at 42 h. Mitochondrial electron transport chain and ATP synthesis proteins [i.e. NDUFB8, COX I and ATP synthase ¿ (ATPS ¿)] were depleted at 42 h after LPS injection. Protein levels of PGC-1¿, the master regulator of mitochondrial biogenesis, were also reduced at 42 h. These findings reveal that impaired mitochondrial function is a critical event in LPS-induced AKI. We previously reported that transforming growth factor (TGF) ¿1 is a potent and rapid inhibitor of mitochondrial function in primary cultures of renal proximal tubular cells (RPTC). We show that renal TGF- ¿1 increased following LPS injection in mice. Furthermore, blockade of TGF- ¿1 receptor signaling after LPS-induced AKI improved renal function and restored PGC-1¿ gene expression in the kidney at 42 h. We hypothesize that LPS-induced production of renal TGF- ¿1 suppresses mitochondrial function and biogenesis, and delays recovery of mitochondrial and renal function following AKI. We will examine this hypothesis with two Specific Aims. Specific Aim 1 is to determine the mechanism of TGF- ¿1-induced mitochondrial suppression in LPS-induced AKI in mice. Specific Aim 2 is to determine the effect of TGF- ¿1 blockade on recovery of mitochondrial and renal function in LPS-induced AKI in mice. We will use pharmacological and genetic models of TGF- ¿ pathway inhibition and examine renal mitochondrial function using intravital confocal multiphoton microscopy (ICMM) as well as ex vivo measures of mitochondrial respiration and homeostasis to address these aims. Dr. Stallons will acquire advanced training in new research methodologies including ICMM and flow cytometric determination of renal inflammatory cells. Career development is another focus of the Training Plan, and Dr. Stallons will gain experience in grant writing, scientific presentations, and teaching during this fellowship. The long-term goal of this project are 1) to elucidate the mechanisms of sepsis-induced acute kidney injury (AKI) and the recovery thereof and 2) to develop Dr. Stallons' scientific and communication skills in order to prepare him to compete for a career development award and pursue a career in academic research.

描述（由适用提供）：由败血症，缺血/再灌注（I/R），药物和创伤引起的细胞损伤和死亡，导致包括肾脏在内的许多器官失败。线粒体功能障碍是这些损伤的普遍结果，也是细胞损伤和死亡的主要机制。虽然线粒体功能障碍发生在AKI之后，但线粒体功能在损伤和败血症引起的AKI的恢复阶段的状态和作用尚不清楚。我们最近在小鼠的脂多糖（LPS）模型中检查了肾小管和线粒体功能。肾小球过滤在18小时时正常，但在注射LPS后42小时降低（即血清肌酐升高）。尿量在42小时时最小。线粒体电子传输链和ATP合成蛋白[即NDUFB8，COX I和ATP合酶（ATPSCO）在LPS注射后42小时耗尽。 PGC-1的蛋白质水平是线粒体生物发生的主要调节剂，在42小时时也降低了。这些发现表明，线粒体功能受损是LPS诱导的AKI的关键事件。我们先前报道说，转化生长因子（TGF）»是肾近端结核细胞（RPTC）原代培养物中线粒体功能的潜在抑制剂。我们表明，小鼠LPS注射后肾脏TGF-»增加了1次。此外，LPS诱导的AKI后TGF-»1接收器信号的阻塞改善了肾功能，并在42小时时恢复了肾脏中的PGC-1基因表达。我们假设LPS诱导的肾脏TGF-»1抑制了线粒体功能和生物发生，并延迟了AKI后线粒体和肾功能的恢复。我们将以两个具体的目的检查这一假设。具体目的1是确定在小鼠LPS诱导的AKI中TGF-»1诱导的线粒体抑制的机理。具体目的2是确定TGF-»1桶对小鼠LPS诱导的AKI线粒体和肾功能恢复的影响。我们将使用内部共聚焦多光学显微镜（ICMM）（ICMM）以及线粒体呼吸和稳态的实面测量来使用TGF-途径抑制和检查肾脏线粒体功能的药物和遗传模型。 Stallons博士将获得新的研究方法的高级培训，包括ICMM和流式细胞术的肾脏炎症细胞。职业发展是培训计划的另一个重点，Stallons博士将在此研究金期间获得赠款写作，科学演示和教学的经验。该项目的长期目标是1）阐明败血症引起的急性肾脏损伤（AKI）的机制及其恢复2），以发展Stallons博士的科学和沟通技巧，以便为他准备竞争职业发展奖并寻求学术研究的职业。