Oxidant stress and diabetic endothelial dysfunction

描述(申请人提供)：我们发表的数据和在本申请中提供的初步数据表明，高血糖抑制AMPK，后者反过来延长糖尿病患者的氧化应激和血管损伤。这一应用的中心假设是，AMPK12抑制增加了26S的活性，从而增加了I：B1的降解，p65核的定位，以及随后的NF：B的激活。活化的核因子：B结合NAD(P)H氧化酶亚基的启动子，包括NOX4、gp91Phox(NOX2)、p67Phox、p47Phox，导致NAD(P)H氧化酶活性和ROS增加，从而导致内皮细胞功能障碍和动脉粥样硬化加速。26S蛋白酶体的慢性抑制通过抑制蛋白酶体依赖的NF：B介导的NAD(P)H氧化酶的激活来预防内皮功能障碍和动脉粥样硬化的形成。这一假设将在三个相互关联的目标中得到检验。前两个目标旨在确定慢性高血糖抑制AMPK是否起作用(目标1)，以及AMPK抑制是否导致糖尿病患者黏附分子异常表达和氧化应激(目标2)。最后，我们将测试RNS介导的AMPK抑制在糖尿病加速动脉粥样硬化发展中的作用(目标3)。尽管糖尿病中动脉粥样硬化、氧化应激和AMPK之间的体内关系无疑是复杂的，但AMPK在氧化应激和动脉粥样硬化中的新作用值得进一步研究。这里提出的研究是确定ONOO-和AMPK抑制在糖尿病血管功能障碍和动脉粥样硬化发病机制中的作用的第一组权威性研究。因此，他们有可能解释长期以来公认的AMPK下降，这种下降发生在动物和人类糖尿病患者身上。我们相信，拟议的研究将提供新的信息，关于糖尿病相关的代谢应激如何导致内皮损伤，内皮细胞如何试图保护自己免受这些应激的影响，以及ONOO-1或AMPK是否是潜在的治疗靶点。

DESCRIPTION (provided by applicant): Our published data and the preliminary data presented in this application have demonstrated that hyperglycemia suppresses AMPK, which in turn perpetuates oxidative stress and vascular injury in diabetes. The central hypothesis of this application is that AMPK12 inhibition increases 26S activity, which increases I:B1 degradation, p65 nucleus localization, and consequent NF:B activation. Activated NF:B binds to the promoter of NAD(P)H oxidase subunits, including NOX4, gp91phox(NOX2), p67phox, p47phox, resulting in an increase in NAD(P)H oxidase activity and ROS, which causes endothelial cell dysfunction and accelerated atherosclerosis. Chronic proteasome inhibition of the 26S proteasome prevents endothelial dysfunction and atherogenesis by inhibiting proteasome-dependent NF:B-mediated activation of NAD(P)H oxidase. This hypothesis will be tested in three interrelated aims. These first two aims are designed to establish whether chronic hyperglycemia inhibition AMPK functions (Aim #1) and whether AMPK inhibition causes abnormal expression of adhesion molecules and oxidant stress in diabetes (Aim #2). Finally, we will test the contributions of RNS-mediated AMPK inhibition in the development of accelerated atherosclerosis in diabetes (Aim #3). Although the in vivo relationships among atherosclerosis, oxidant stress, and AMPK in diabetes are undoubtedly complex, the emerging role for AMPK in oxidant stress and atherosclerosis warrant further study. The studies proposed here represent the first set of definitive studies to determine the role of ONOO- and AMPK inhibition in the pathogenesis of diabetic vascular dysfunction and atherosclerosis. As such, they have the potential to explain the long recognized decrease in AMPK that occurs in animals and human patients with diabetes. We believe that the proposed studies will provide novel information as to how the metabolic stress associated with diabetes causes damage to the endothelium and how the endothelial cell attempts to protect itself against these stresses and whether ONOO- or AMPK are potential targets for therapy.