TRPC Channels in the Metabolic Syndrome

代谢综合征中的 TRPC 通道

• 批准号: 8345749
• 负责人: Alexander G. Obukhov
• 金额: $ 51.14万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8345749
• 关键词: Adult; Aldosterone; American; Angiotensin II; Animal Model; Area; Arterial Fatty Streak; Arteries; Atherosclerosis; Biochemical; Biological; Blood Vessels; Cardiovascular Diseases; Cause of Death; Cell Proliferation; Cell membrane; Central obesity; Cessation of life; Characteristics; Cholesterol; Complementary DNA; Coronary; Coronary Arteriosclerosis; Coronary artery; Development; Disease Progression; Dominant-Negative Mutation; Down-Regulation; Dyslipidemias; Electroporation; Exhibits; Experimental Designs; Family suidae; Fluorometry; Functional disorder; Gene Delivery; Glucose Intolerance; Goals; Histamine; Hormones; Human; Hypertension; Injury; Insulin Resistance; Ion Channel; Isometric Exercise; Lead; Measurement; Mediating; Metabolic syndrome; Microinjections; Mineralocorticoid Receptor; Mineralocorticoids; Modeling; Molecular; Myocardial Infarction; Obesity; Organ Culture Techniques; Outcome; Phosphotransferases; Plasma; Prevalence; Relative (related person); Renin; Renin-Angiotensin-Aldosterone System; Research; Role; Sarcoplasmic Reticulum; Sclerosis; Severities; Signal Pathway; Signal Transduction; Site; Smooth Muscle Myocytes; Spironolactone; Stenosis; Surface; TRP channel; Techniques; Therapeutic Effect; Ultrasonography; Up-Regulation; Vascular Diseases; Vasoconstrictor Agents; clinically significant; defined contribution; fasting glucose; fluorescence imaging; in vivo; inhibitor/antagonist; injured; migration; neointima formation; novel; novel strategies; oxidant stress; prevent; programs; receptor; receptor operated channel; response; small hairpin RNA; sound; targeted delivery; treatment strategy; voltage

DESCRIPTION (provided by applicant): Canonical TRP channels (TRPC) form store- and receptor-operated Ca2+-permeable channels in the plasma membrane of vascular smooth muscle cells. TRPCs have been implicated in regulating vascular tone and smooth muscle cell proliferation. This proposal will define the molecular roles of TRPC channels during coronary artery remodeling associated with metabolic syndrome (MetS). MetS is characterized by central obesity, elevated plasma cholesterol and fasting glucose, hypertension, insulin resistance, and atherosclerosis. The prevalence of MetS among adults in the USA is 24%. In this research program, we will utilize the MetS Ossabaw pig model that exhibits all of the characteristics of MetS, including the overactive renin-angiotensin- aldosterone system (RAAS). We demonstrated that the expression levels of TRPC1 and TRPC6 channels are markedly elevated in MetS Ossabaw pig coronary arteries exhibiting atherosclerosis and hypercontractility. Consistently, freshly isolated MetS coronary artery smooth muscle cells had elevated store-/receptor-operated Ca2+ influx and large store-/receptor-operated TRPC-like currents. Since angiotensin II and aldosterone are positive regulators of TRPC expression, we hypothesize that, in MetS, the overactive RAAS upregulates TRPC1 and TRPC6 expression, which drives increased coronary smooth muscle cell proliferation and coronary artery hypercontractility. The following Specific Aims will be pursued: 1) To determine how the molecular expression of TRPCs is altered during the MetS-associated remodeling of coronary artery smooth muscle cells; 2) To define the contribution of TRPCs to endogenous store- and receptor-activated Ca2+ influx/currents in control and MetS coronary artery smooth muscle cells; 3) To determine whether the functional expression of endogenous TRPC channels is directly regulated by RAAS components, angiotensin II and Aldo, in coronary artery smooth muscle cells; 4) To determine whether the in vivo, coronary artery targeted down- regulation of TRPCs slows atheroma progression and decreases coronary artery hypercontractility in MetS pigs. During this research program, we will use molecular biological, biochemical, electrophysiological, and fluorescence imaging approaches as well as intravascular ultrasound, isometric tension and coronary artery ring lumen area measurements. Additionally, a coronary artery targeted delivery approach will be employed to deploy shRNAs and cDNA constructs into the coronary artery wall in vivo. Importantly, we will determine the distinct roles of TRPC1 and TRPC6 during MetS-associated NATIVE atherosclerosis progression. PUBLIC HEALTH RELEVANCE: The results of this study will determine the molecular mechanisms involved in regulating TRPC channel expression in atherosclerotic MetS coronary arteries and define the channel's role in MetS-associated coronary dysfunctions. PUBLIC HEALTH RELEVANCE: The results of this study will determine the molecular mechanisms involved in regulating TRPC channel expression in metabolic syndrome coronary arteries presenting with atherosclerosis and define the channel's role in metabolic syndrome-associated coronary dysfunctions. Because TRPCs are also expressed in cerebral arteries, the results of this proposal may be critical for our understanding of the molecular mechanisms underlying some cerebral artery dysfunction implicated in stroke.

描述（由申请方提供）：典型TRP通道（TRPC）在血管平滑肌细胞质膜中形成钙库和受体操纵的Ca 2+渗透性通道。TRPC参与调节血管张力和平滑肌细胞增殖。该建议将定义TRPC通道在与代谢综合征（MetS）相关的冠状动脉重构过程中的分子作用。代谢综合征的特征是向心性肥胖、血浆胆固醇和空腹血糖升高、高血压、胰岛素抵抗和动脉粥样硬化。美国成年人中MetS的患病率为24%。在这项研究计划中，我们将利用MetS Ossabaw猪模型，表现出MetS的所有特征，包括过度活跃的肾素-血管紧张素-醛固酮系统（RAAS）。我们证明，TRPC 1和TRPC 6通道的表达水平显着升高，在MetS Ossabaw猪冠状动脉表现出动脉粥样硬化和过度收缩。一致地，新鲜分离的MetS冠状动脉平滑肌细胞具有升高的储存/受体操纵的Ca 2+内流和大的储存/受体操纵的TRPC样电流。由于血管紧张素II和醛固酮是TRPC表达的正调控因子，我们推测，在MetS中，过度活跃的RAAS上调TRPC 1和TRPC 6的表达，从而驱动冠状动脉平滑肌细胞增殖和冠状动脉过度收缩。本研究的具体目的如下：1）确定在MetS相关的冠状动脉平滑肌细胞重构过程中TRPC的分子表达是如何改变的; 2）确定TRPC对对照和MetS冠状动脉平滑肌细胞中内源性钙库和受体激活的Ca 2+内流/电流的贡献;（3）研究RAAS组分血管紧张素II和Aldo是否直接调节冠状动脉平滑肌细胞内源性TRPC通道的功能表达; 4）确定TRPC的体内冠状动脉靶向下调是否减缓MetS猪中的动脉粥样化进展并降低冠状动脉过度收缩性。在这项研究计划中，我们将使用分子生物学，生物化学，电生理学和荧光成像方法以及血管内超声，等长张力和冠状动脉环管腔面积测量。此外，将采用冠状动脉靶向递送方法将shRNA和cDNA构建体部署到体内冠状动脉壁中。重要的是，我们将确定TRPC 1和TRPC 6在MetS相关的天然动脉粥样硬化进展过程中的不同作用。 公共卫生关系：本研究的结果将确定参与调节TRPC通道在动脉粥样硬化MetS冠状动脉中表达的分子机制，并确定该通道在MetS相关冠状动脉功能障碍中的作用。 公共卫生相关性：这项研究的结果将确定参与调节TRPC通道表达的代谢综合征冠状动脉粥样硬化的分子机制，并确定通道在代谢综合征相关的冠状动脉功能障碍中的作用。由于TRPC也在脑动脉中表达，因此该提议的结果可能对我们理解与中风有关的某些脑动脉功能障碍的分子机制至关重要。