Novel redox mechanisms of oxygenated phospholipids in chronic and diabetic kidney disease

慢性和糖尿病肾病中含氧磷脂的新氧化还原机制

基本信息

批准号：
10752954
负责人：
Krisztian Stadler
金额：
$ 29.98万
依托单位：
LSU PENNINGTON BIOMEDICAL RESEARCH CTR
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-15 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10752954
关键词：
Ablation Acyl Coenzyme A Address Antioxidants Apoptosis Apoptotic Arachidonate 15-Lipoxygenase Attributes of Chemicals Biochemical Biological Biology Biophysics Cell Death Cell Death Signaling Process Cell physiology Cells Cellular Metabolic Process Chronic Chronic Kidney Failure Coenzyme A Ligases Complex Complications of Diabetes Mellitus Consumption Coupled Cytoplasm Data Dependence Diabetes Mellitus Diabetic Nephropathy Disease Distant Electron Spin Resonance Spectroscopy Epithelial Cells Equilibrium Event Foundations Free Radicals Functional disorder Future Generations Injury Injury to Kidney Intervention Iron Iron Chelation Kidney Kidney Diseases Kinetics Link Lipid Peroxidation Lipid Peroxides Lipids Lysophospholipids Mediator Membrane Metabolic Metabolism Mitochondria Modeling Molecular Molecular Profiling Monitor Mus Obesity Outcome Oxidation-Reduction Oxidative Stress Oxygen Pathogenesis Pathway interactions Peroxides Phosphatidylethanolamine Phospholipids Production Proteins Publishing Reaction Reactive Oxygen Species Role Signal Transduction Site Source Specificity Stress Structure Superoxides Testing Transgenic Model Transgenic Organisms Tubular formation Work biophysical techniques cell injury cold temperature design diabetic diet-induced obesity experimental study feeding glutathione peroxidase imaging modality in vivo kidney cell mass spectrometric imaging mitochondrial dysfunction mouse model novel oxidation oxidized lipid peroxidation pharmacologic prevent programs successful intervention transmission process

项目摘要

Oxidative stress has long been implicated in the pathogenesis of diabetic and chronic kidney disease (DKD/CKD). Most of the previous studies focused on either a singular concept of oxidative stress vs antioxidant balance, or centered on overproduction of superoxide as a major reactive oxygen species (ROS) and a primary event in DKD/CKD. However, superoxide has major kinetic and biochemical barriers that limit its impacts on biological structures. We propose a key role for less reactive, more specific and membrane diffusible molecules which are also tightly related to changes in cell metabolism – (phospho)lipid peroxides (LOOH). While the basic tenets of lipid peroxidation are established in biology, the molecular entity, modes of action and specific redox signaling ability of LOOH are more enigmatic. This is a critical gap to address because impeding a highly specific form of redox signal at the right timing in disease pathogenesis can prevent renal cell dysfunction. Our central hypothesis is that LOOH are key metabolic signals that transmit an initial redox stress in cells. Furthermore, we propose that diabetes alters the molecular signature of LOOH and that from a myriad of diverse oxidized phospholipids, there are only a few specific ones that dictate the activation of programmed cell death. We focus on proximal tubular epithelial cells (PTC) which comprise ~ 70-80 % of the cortex, where we previously discovered that dysregulation of PTC metabolism potentiates LOOH production. We have a broad array of preliminary data showing that when PTC metabolism is challenged either by lipid overload or by ablating the neutralizing mechanism for membrane peroxides via deletion of glutathione peroxidase 4 (GPx4), LOOH are overproduced and mice develop kidney injury. Using diabetic models, we show that diabetes not only potentiates the formation of LOOH, but also alters the molecular signature of LOOH species in a fashion that oxidized phosphatidylethanolamines (PE) and lysophosphatidylethanolamine (LPE) become abundant. Three aims will test the hypothesis using state-of-the-art biophysical and mass spectrometry imaging methods in combination with pharmacologic and transgenic approaches using both established and newly generated mouse models. In Aim 1, we will test the prediction that changes in PTC metabolic activity regulates the production of LOOH. Aim 2 will explore mechanisms through which diabetes potentiates the production of specific oxygenated phospholipids. In Aim 3, we will test the hypothesis, that selective oxidation of phospholipid species dictates the activation of renal cell death programs. The experimental strategy combines PTC-specific transgenic models, obese CKD and diabetic DKD models, using targeted compounds to delinate originating sources of redox stress and advanced redox phospholipidomics and biophysical approaches. Outcomes from this proposal will establish a new, more specific view of redox stress in CKD/DKD and link specific oxidized (phospho)lipids to PTC injury and demise, paving the way to highly specific anti-apoptotic or anti-ferroptotic interventions in the future.

氧化应激长期以来一直隐含在糖尿病和慢性肾脏疾病的发病机理中（DKD/CKD）。以前的大多数研究都集中在氧化应激的奇异概念上抗氧化剂平衡，或以超氧化物的过量生产为主要活性氧（ROS）以及DKD/CKD中的主要事件。但是，超氧化物具有主要的动力学和生化障碍，可以限制其对生物结构的影响。我们提出了反应性较低，更具体和膜的关键作用与细胞代谢变化紧密相关的扩散分子 - （磷）脂质过氧化物（looh）。虽然脂质过氧化的基本原则是在生物学中建立的，但分子实体，模式 LOOH的动作和特定的氧化还原信号传导能力更神秘。这是解决的关键差距因为在疾病发病机理中，在正确的时机上阻碍了高度特定的氧化还原信号形式肾细胞功能障碍。我们的中心假设是LOOH是传输初始的关键代谢信号细胞中的氧化还原应激。此外，我们建议糖尿病改变Looh的分子特征，并改变从无数的潜水员氧化磷脂中，只有少数特定的磷脂决定了激活的激活程序性细胞死亡。我们专注于近端管状上皮细胞（PTC），该细胞完成了约70-80％皮质，以前我们发现PTC代谢的失调增强了Looh的产生。我们有广泛的初步数据，表明当PTC代谢受到脂质挑战时超负荷或通过擦拭膜过氧化膜的中和机制，通过缺失谷胱甘肽过氧化物酶4（GPX4），LooH产生过多，小鼠会出现肾脏损伤。使用糖尿病模型，我们表明糖尿病不仅有可能形成LooH，而且还改变了分子特征以氧化磷脂酰乙醇胺（PE）和溶血磷脂酰乙醇胺氧化的方式的LooH物种（LPE）变得丰富。三个目标将使用最先进的生物物理和质量检验假设光谱成像方法与药物和转基因方法结合使用建立并新生成的鼠标模型。在AIM 1中，我们将测试PTC变化的预测代谢活性调节LOOH的产生。 AIM 2将探索糖尿病的机制增强特定氧化磷脂的产生。在AIM 3中，我们将检验以下假设，即磷脂物种的选择性氧化决定了肾细胞死亡程序的激活。这实验策略结合了PTC特异性转基因模型，肥胖的CKD和糖尿病DKD模型，使用靶向化合物分散了氧化还原应力和晚期氧化还原磷脂属的来源和生物物理方法。该提案的结果将建立一个新的，更具体的氧化还原观点 CKD/DKD中的应力，并将特异性氧化（磷酸）脂质与PTC损伤和灭亡联系起来，铺平了通往通往的道路将来采取高度特异性的抗凋亡或抗凋亡干预措施。