Endothelial function in human diabetes: role of mitochondrial fission proteins

 描述（由申请人提供）：全球糖尿病（DM）的患病率已飙升至3.8亿人以上。这些患者发病和死亡的主要原因是糖尿病相关的大血管和微血管疾病。糖尿病血管疾病与非糖尿病患者中观察到的血管疾病具有关键的病理生理学差异。目前，与非DM患者相比，对抗血管疾病的治疗在DM患者中的有效性显著降低。针对糖尿病血管疾病中特别重要的病理生理学通路的新疗法可能为减少糖尿病血管不良事件提供显著益处。糖尿病血管疾病开始于血管内皮功能障碍的发展-一种以血管炎症增加和血管收缩和促血栓形成倾向增加为特征的状态。在糖尿病中，我们和其他人已经发现内皮功能障碍可以由继发于过度线粒体分裂的内皮线粒体功能的关键变化引发。这些变化在急性暴露于异常葡萄糖后出现，在DM的慢性异常葡萄糖暴露期间也很明显。我们的初步数据表明，高或低葡萄糖暴露和慢性糖尿病内皮功能障碍的内皮功能的急性损伤发生通过一个共同的机制-激活和结合的动力相关蛋白-1（Drp 1），细胞溶质为基础的GTdR酶，对接蛋白位于外线粒体膜。这种结合引发过度的线粒体分裂并触发线粒体和内皮功能障碍。此外，我们的初步数据强烈建议Fis 1是关键的Drp 1对接蛋白在这个过程中。该申请采用了一种创新的翻译方法，独特地结合了关键的药理学和分子研究，靶向来自人类受试者的完整人类血管和内皮细胞中的Drp 1-Fis 1相互作用，以及基于结构的药物设计和在相关患者来源组织中测试所得化合物。我们的方法有很大的希望直接导致确定一个一流的药物，可以显着减少心脏病发作，中风，周围血管疾病，肾脏疾病，失明，和神经病变，在世界上近4亿例糖尿病患者。在目标1中，我们将确定急性体内暴露于高或低葡萄糖水平是否诱导线粒体分裂和过量线粒体活性氧产生。此外，我们将确定是否损害的内皮依赖性血管舒张和一氧化氮（NO）的生物利用度在完整的小动脉从DM患者是Drp 1和/或Fis 1依赖的方式。在目的2中，我们将确定是否可以通过抑制Fis 1和/或Drp 1表达来逆转糖尿病患者完整小动脉中内皮依赖性血管舒张和NO生物利用度的慢性损伤。在目标3中，我们将鉴定特异性破坏Drp 1-Fis 1相互作用的小分子，验证这些发现，并测试这些小分子对来自DM受试者的离体人小动脉的功效。

 DESCRIPTION (provided by applicant): The prevalence of diabetes (DM) worldwide has soared above 380 million individuals. The primary causes of morbidity and mortality in these patients are diabetes-related macrovascular and microvascular disease. DM vascular disease has critical pathophysiological differences from vascular disease seen in non-DM patients. Currently therapies to combat vascular disease are significantly less effective in DM patients compared to non-DM patients. Novel therapies targeted at disrupting pathophysiological pathways of particular importance in DM vascular disease may offer significant benefits for the reduction of adverse vascular events in DM. DM vascular disease begins with the development of vascular endothelial dysfunction-a state characterized by increased vascular inflammation and increased vasoconstrictive and pro-thrombotic tendencies. In DM, we and others have discovered endothelial dysfunction can be initiated by critical changes in endothelial mitochondrial function occurring secondary to excessive mitochondrial fission. These changes appear both following acute exposure to abnormal glucose as well as being evident during the chronic abnormal glucose exposures of DM. Our preliminary data suggest both acute impairment of endothelial function by high or low glucose exposure and chronic DM endothelial dysfunction occur through a common mechanism-the activation and binding of dynamin-related protein-1 (Drp1), a cytosolic-based GTPase enzyme, to docking proteins located on the outer mitochondrial membrane. This binding initiates excessive mitochondrial fission and triggers mitochondrial and endothelial dysfunction. Further, our preliminary data strongly suggest Fis1 is the critical Drp1 docking protein in this process. This application employs an innovative translational approach that uniquely combines critical pharmacological and molecular studies targeting the Drp1-Fis1 interaction in intact human vessels and endothelial cells from human subjects with structure-based drug design and testing of resulting compounds in relevant patient-derived tissues. Our approach holds great promise to lead directly to identifying a first-i-class pharmacological agent that could significantly reduce heart attacks, strokes, peripheral vascular disease, renal disease, blindness, and neuropathy in the world's nearly 400 million cases of diabetes. In Aim 1, we will determine whether acute in vivo exposure to high or low glucose levels induces mitochondrial fission and excess mitochondrial reactive oxygen species production. Further, we will determine whether impairment of endothelium-dependent vasodilation and nitric oxide (NO) bioavailability in intact arterioles from DM patients is Drp1 and/or Fis1-dependent manner. In Aim 2, we will determine whether the chronic impairment of endothelium-dependent vasodilation and NO bioavailability in intact arterioles from human with DM can be reversed by suppression of Fis1 and/or Drp1 expression. In Aim 3, we will identify small molecules to that specifically disrupt the Drp1-Fis1 interaction, validate these findings, an test the efficacy these small molecules on ex vivo human arterioles from DM subjects.