Mitochondrial Carbonic Anhydrases and Diabetic Blood-Brain Barrier Disruption

线粒体碳酸酐酶和糖尿病血脑屏障破坏

基本信息

批准号：
8213409
负责人：
WILLIAM A BANKS
金额：
$ 32.1万
依托单位：
SAINT LOUIS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-02-01 至 2015-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8213409
关键词：
Acetyl Coenzyme A Affect Apoptosis Astrocytes Bicarbonates Binding Blood Blood - brain barrier anatomy Blood Vessels Blood-Retinal Barrier Brain Carbonic Anhydrase Inhibitors Catabolism Cell Respiration Cells Citric Acid Citric Acid Cycle Coculture Techniques Communication Complications of Diabetes Mellitus Cytoplasm Deterioration Development Diabetes Mellitus Drug usage Electron Transport Endothelial Cells Extravasation Functional disorder Generations Glucose Hexosamines Hyperglycemia In Vitro Insulin Insulin Resistance Knock-out Laboratories Lead Marketing Measures Membrane Metabolism Methods Mitochondria Modeling Mus Nervous System Physiology Neuraxis Oxaloacetates Oxidative Stress Pathway interactions Pericytes Pharmaceutical Preparations Plasma Proteins Process Production Property Pyruvate Reactive Oxygen Species Resistance Retinal Role Serum Proteins Source Streptozocin System Testing Toxic effect Translational Research Wild Type Mouse Work aerobic glycolysis carbonate dehydratase cell type diabetic glucose metabolism in vitro Model in vivo in vivo Model inhibitor/antagonist mitochondrial membrane neurovascular unit overexpression polyol prevent public health relevance research study

项目摘要

DESCRIPTION (provided by applicant): Diabetes mellitus is associated with deterioration of the brain's microvasculature and the blood-brain barrier (BBB) that it forms. The BBB prevents the unrestricted leakage of plasma proteins into the brain. The vascular BBB is physically formed by specially modified brain endothelial cells (BECs), but other cell types interact with it to form the neurovascular unit (NVU). Pericytes in particular are important in maintaining BBB function in the face of glycemic insult. We have shown in vitro that the insulin transporter is lost in the face of high glucose concentrations unless BECs are co-cultured with pericytes; astrocyte co-culture does not preserve BEC insulin transporter function. However, pericytes are themselves susceptible to glucose toxicity and the accompanying oxidative stress. Work with retinal pericytes and the blood-retinal barrier (BRB) shows that hyperglycemia induces apoptosis in retinal pericytes; with pericyte loss the BRB deteriorates. Mitochondrial carbonic anhydrases (CAs) are important in the generation of reactive oxygen species (ROS) and the subsequent oxidative stress that arises and is accelerated during hyperglycemia. In brief, mitochondrial CAs generate mitochondrial bicarbonate that is necessary for the oxidative catabolism of glucose, the major source of ROS. Hyperglycemia accelerates this process, increasing production of ROS. Blocking mitochondrial CAs shuttles pyruvate through anaerobic metabolism and so prevents excessive ROS production. We hypothesize that inhibition of mitochondrial carbonic anhydrases (CAs) will protect pericytes and BECs from ROS induced apoptosis and slow the development of disruption of the BBB in STZ-induced diabetes. Wewill test this hypothesis in two specific aims. SA1 will measure oxidative stress induced by high glucose media and the resulting mitochondrial leakage and apoptosis in primary cultures of brain pericytes and BEC isolated from mitochondrial CA KO & WT mice and in pericytes and BEC that overexpress CA or are treated with clinically used CA inhibitors. SA 2 will measure in diabetic and control mice BBB disruption and oxidative stress in BEC from CA KO mice, WT mice, and mice treated with the CA inhibitors of SA1. PUBLIC HEALTH RELEVANCE: We will investigate a mechanism that could explain why diabetics develop problems with the small vessels of the brain and drugs that could reverse those problems. If successful, a major complication of diabetes might be treatable with a class of drugs already on the market.

描述（由申请人提供）：糖尿病与大脑微血管系统及其形成的血脑屏障（BBB）的恶化有关。血脑屏障可防止血浆蛋白不受限制地渗漏到大脑中。血管 BBB 在物理上由经过特殊修饰的脑内皮细胞 (BEC) 形成，但其他细胞类型与其相互作用形成神经血管单元 (NVU)。周细胞对于在血糖损伤时维持血脑屏障功能尤其重要。我们已经在体外证明，除非 BEC 与周细胞共培养，否则胰岛素转运蛋白在高葡萄糖浓度下会丢失；星形胶质细胞共培养不保留 BEC 胰岛素转运蛋白功能。然而，周细胞本身容易受到葡萄糖毒性和伴随的氧化应激的影响。对视网膜周细胞和血视网膜屏障（BRB）的研究表明，高血糖会诱导视网膜周细胞凋亡；随着周细胞的损失，BRB 会恶化。线粒体碳酸酐酶 (CA) 在活性氧 (ROS) 的产生以及随后在高血糖期间出现并加速的氧化应激中发挥着重要作用。简而言之，线粒体 CA 产生线粒体碳酸氢盐，这是葡萄糖氧化分解代谢所必需的，而葡萄糖是 ROS 的主要来源。高血糖会加速这一过程，增加活性氧的产生。阻断线粒体 CAs 通过无氧代谢运输丙酮酸，从而防止过多的 ROS 产生。我们假设抑制线粒体碳酸酐酶 (CA) 将保护周细胞和 BEC 免受 ROS 诱导的细胞凋亡，并减缓 STZ 诱导的糖尿病中 BBB 破坏的发展。我们将在两个具体目标中检验这一假设。 SA1 将测量高葡萄糖介质诱导的氧化应激，以及从线粒体 CA KO 和 WT 小鼠中分离的脑周细胞和 BEC 的原代培养物以及过度表达 CA 或用临床使用的 CA 抑制剂治疗的周细胞和 BEC 的原代培养物中产生的线粒体渗漏和细胞凋亡。 SA 2 将测量糖尿病小鼠和对照小鼠的 BBB 破坏以及来自 CA KO 小鼠、WT 小鼠和用 SA1 的 CA 抑制剂治疗的小鼠的 BEC 中的氧化应激。公共健康相关性：我们将研究一种机制，可以解释为什么糖尿病患者会出现大脑小血管问题，以及可以逆转这些问题的药物。如果成功的话，糖尿病的主要并发症可能可以用市场上已有的一类药物来治疗。