Pharmacological Restoration of Diabetic Vascular Dysfunction

糖尿病血管功能障碍的药理恢复

• 批准号: 8966651
• 负责人: JANE E REUSCH
• 金额: --
• 依托单位: VA EASTERN COLORADO HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2017-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8966651
• 关键词: Address; Affect; Antioxidants; Autophagocytosis; Biogenesis; Blood Vessels; Cardiovascular Diseases; Cardiovascular system; Cell Proliferation; Cells; Clinical; Complex; Data; Deoxyglucose; Diabetes Mellitus; Diabetic Angiopathies; Dipeptidyl Peptidases; Endothelial Cells; Equilibrium; Exercise; Fatty acid glycerol esters; Glucose; Goals; Health; High Fat Diet; Homeostasis; Human; Hyperglycemia; Impairment; In Vitro; Intervention; Mediating; Mitochondria; Mitochondrial Proteins; Modeling; Modification; Morbidity - disease rate; Mus; Nitric Oxide; Nitric Oxide Synthase; Nutrient; Oxidants; Oxidative Stress; Pathway interactions; Pharmaceutical Preparations; Population; Process; Production; Publishing; Pyruvaldehyde; Randomized; Rattus; Reactive Oxygen Species; Regulation; Reporting; Respiration; Risk Factors; Risk Reduction; Role; Running; Signal Pathway; Signal Transduction; Smooth Muscle Myocytes; Stress; Structure; Testing; Therapeutic; Vascular Diseases; Veterans; cardiovascular disorder risk; cardiovascular risk factor; diabetic; diabetic rat; fitness; genetic approach; glucagon-like peptide; improved; in vivo; inhibitor/antagonist; insulin secretion; macrovascular disease; male; mitochondrial dysfunction; mortality; mouse model; new therapeutic target; novel; novel strategies; novel therapeutic intervention; nutrient deprivation; protein expression; research study; response; restoration; therapeutic target; treatment duration; vasomotion

DESCRIPTION (provided by applicant): Problem: Diabetes (DM) increases cardiovascular (CV) and all-cause mortality despite aggressive risk factor modification. Our long term goal is to define novel targets for cardiovascular risk reduction in diabetes. Vascular mitochondria are a potential new target. Mitochondria regulate endothelial function and smooth muscle cell (SMC) proliferation and mitochondrial dysfunction is a hallmark of diabetes. Exercise elicits an adaptive improvement in mitochondrial quality in healthy vessels; this response is absent in diabetes. The question addressed in this proposal is whether pharmacological targeting of eNOS and SIRT with glucagon- like peptide 1 (GLP-1) can restore signaling to mitochondrial biogenesis and improve mitochondrial dynamics and vascular function. GLP-1 is a diabetes medication that also induces eNOS, SIRT1, mitochondrial biogenesis and autophagy 21. New preliminary data suggest that saxagliptin (SAXA), a dipeptidyl peptidase-4 inhibitor that increases circulating endogenous GLP-1, restores induction of eNOS and mitochondrial protein expression with exercise in DM and improves running distance. Hypotheses: Abnormal mitochondrial function and impaired stress mediated mitochondrial dynamics in the diabetic vasculature will be improved by GLP-1 via eNOS and SIRT1 signaling. SA #1: What is the impact of GLP-1 on vascular mitochondrial adaptation in DM? Rationale: Control rats subjected to 8 day exercise show increased activation of the mitochondrial biogenesis, improved mitochondrial function plus increased fusion and decreased fission. We will examine the impact of GLP-1 on vascular mitochondrial function and turnover in diabetes and use targeted deletion of eNOS, endothelial cell (EC) SIRT1, SMC SIRT1 with or without exercise to test mitochondrial homeostatic adaptation in vivo. Hypothesis 1.1: Intervention with GLP-1 will improve mitochondrial function through augmentation of vascular mitochondrial adaptation (biogenesis, fusion and autophagy) to exercise in high fat induced diabetes. Hypothesis 1.2: eNOS and/or SIRT1 are required for GLP-1 rescue of mitochondrial adaptation. Approach: 1a. Male C57BL6 on chow versus high fat (HF) diet for 10 weeks will be randomized to GLP-1 or vehicle with or without exercise for 8 days. 1b. c57eNOS -/- and c57b eNOS +/+ will be treated as in SA1a. 1c. c57 mice with EC or SMC deletion of SIRT1 and controls will be treated as in SA1a. These experiments will clarify the importance of eNOS and SIRT1 for vascular mitochondrial adaptation to exercise in vivo and define the impact of diabetes and GLP-1 on these pathways. SA #2: How does diabetes affect dynamic mitochondrial adaptation in vascular cells in vitro? Rationale: Regulation of mitochondrial function requires a complex interplay between mitochondrial biogene- sis and remodeling through fission, fusion and autophagy. Hypothesis 2.1: Endothelial cells and/or smooth muscle cells from DM models will have impaired mitochondrial dynamics. Hypothesis 2.2: GLP-1 will improve mitochondrial function and dynamics in DM cells through eNOS and/or SIRT. Approach: These experiments will examine the impact of DM and GLP-1 on mitochondrial quality and dynamics in vitro and employ genetic approaches to define the relative contribution of eNOS and SIRT for mitochondrial quality in vascular cells. Impact on the Veteran Population: Mitochondrial dynamics are a novel target to decrease excess CV risk in diabetes. Interventions targeting mitochondrial ROS have been consistently ineffective in human studies. Our observation that 8 days of treatment with SAXA restores vascular induction of mitochondrial biogenesis provides proof of concept that impaired vascular mitochondrial adaptation is targetable with a currently available drug. Pharmacological restoration of mitochondrial dynamics in diabetes could have implications for macrovascular and microvascular complications of diabetes.

描述（由申请人提供）： 问题：尽管积极改变危险因素，但糖尿病 (DM) 仍会增加​​心血管 (CV) 和全因死亡率。我们的长期目标是确定降低糖尿病心血管风险的新目标。血管线粒体是一个潜在的新靶点。线粒体调节内皮功能和平滑肌细胞（SMC）增殖，线粒体功能障碍是糖尿病的标志。运动可引起健康血管线粒体质量的适应性改善；糖尿病中不存在这种反应。该提案解决的问题是，用胰高血糖素样肽 1 (GLP-1) 药理学靶向 eNOS 和 SIRT 是否可以恢复线粒体生物发生的信号传导并改善线粒体动力学和血管功能。 GLP-1 是一种糖尿病药物，还可诱导 eNOS、SIRT1、线粒体生物发生和自噬 21。新的初步数据表明，沙格列汀 (SAXA) 是一种二肽基肽酶 4 抑制剂，可增加循环内源性 GLP-1，恢复 eNOS 和线粒体的诱导。 DM 中运动时的蛋白质表达并提高跑步距离。 假设：GLP-1 通过 eNOS 和 SIRT1 信号传导改善糖尿病脉管系统中异常的线粒体功能和受损的应激介导的线粒体动力学。 SA #1：GLP-1 对 DM 血管线粒体适应有何影响？理由：经过 8 天运动的对照大鼠显示线粒体生物发生的激活增加、线粒体功能改善以及融合增加和裂变减少。我们将研究 GLP-1 对糖尿病患者血管线粒体功能和周转的影响，并在有或没有运动的情况下使用靶向删除 eNOS、内皮细胞 (EC) SIRT1、SMC SIRT1 来测试体内线粒体稳态适应。假设 1.1：GLP-1 干预将通过增强血管线粒体对高脂肪诱导糖尿病运动的适应（生物发生、融合和自噬）来改善线粒体功能。假设 1.2：GLP-1 拯救线粒体适应需要 eNOS 和/或 SIRT1。方法： 1a.雄性 C57BL6 接受食物与高脂肪 (HF) 饮食 10 周后，将被随机分配至 GLP-1 或载体，并进行或不进行运动 8 天。 1b. c57eNOS -/- 和 c57b eNOS +/+ 将按 SA1a 中的方式处理。 1c. EC 或 SMC 缺失 SIRT1 的 c57 小鼠和对照小鼠将按照 SA1a 进行处理。这些实验将阐明 eNOS 和 SIRT1 对于血管线粒体适应体内运动的重要性，并确定糖尿病和 GLP-1 对这些途径的影响。 SA #2：糖尿病如何影响体外血管细胞的动态线粒体适应？理由：线粒体功能的调节需要线粒体生物发生和通过裂变、融合和自噬进行的重塑之间复杂的相互作用。假设 2.1：DM 模型中的内皮细胞和/或平滑肌细胞的线粒体动力学受损。假设 2.2：GLP-1 将通过 eNOS 和/或 SIRT 改善 DM 细胞中的线粒体功能和动力学。方法：这些实验将在体外检查 DM 和 GLP-1 对线粒体质量和动力学的影响，并采用遗传学方法来确定 eNOS 和 SIRT 对血管细胞线粒体质量的相对贡献。 对退伍军人群体的影响：线粒体动力学是降低糖尿病患者过度心血管风险的新目标。针对线粒体 ROS 的干预措施在人类研究中一直无效。我们观察到，8 天的 SAXA 治疗可恢复线粒体生物发生的血管诱导，这证明了目前可用的药物可以针对受损的血管线粒体适应。糖尿病线粒体动力学的药理学恢复可能对糖尿病的大血管和微血管并发症产生影响。