ANG II OPPOSES INS MEDIATED VASORELAXATION & GLU UTILZA

ANG II 反对 INS 介导的血管舒张

• 批准号: 7185818
• 负责人: James Russell Sowers
• 金额: $ 27.26万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-10 至 2009-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7185818
• 关键词: 1-Phosphatidylinositol 3-Kinase; ANG gene; Address; Adipocytes; Adipose tissue; Angiotensin II; Angiotensins; Binding; Binding Proteins; Blood Vessels; Cardiovascular Diseases; Characteristics; Chemosensitization; Complement; Condition; Data; Diabetes Mellitus; Dominant-Negative Mutation; Endothelial Cells; Enzymes; Fatty acid glycerol esters; Generations; Glucose; Hypertension; IGF-1 Signaling Pathway; Impairment; In Vitro; Insulin; Insulin Resistance; Insulin-Like Growth Factor I; Investigation; Knowledge; Laboratories; Liquid Chromatography; Mediating; Metabolism; Modeling; Myosin ATPase; Myosin Light Chains; NAD(P)H oxidase; Na(+)-K(+)-Exchanging ATPase; Nitric Oxide; Nitric Oxide Synthase; Non-Insulin-Dependent Diabetes Mellitus; Obesity; Oxidative Stress; Pathogenesis; Pathology; Pathway interactions; Patients; Peptides; Phosphoric Monoester Hydrolases; Phosphorylation; Play; Post-Translational Protein Processing; Production; Protein Overexpression; Protein phosphatase; Proto-Oncogene Proteins c-akt; Rattus; Reactive Oxygen Species; Relaxation; Resistance; Rhea; Rho-associated kinase; Rodent Model; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Site; Skeletal Muscle; Smooth Muscle Myocytes; Somatomedins; Testing; Tissue Model; Tissues; Transgenic Organisms; Vascular Endothelial Cell; Vasodilation; angiogenin; autocrine; base; glucose disposal; glucose transport; human CYBA protein; in vivo; insulin sensitivity; normotensive; receptor; response; tandem mass spectrometry

Insulin (INS) resistance and hypertension often coexist, and frequently progress to diabetes and cardiovascular disease. INS and its structurally and functionally similar peptide, insulin-like growth factor (IGF-1), both have been shown to promote vasorelaxation, as well as glucose (GLU) disposal. Recent studies in our laboratory suggest that these actions of INS/ IGF-1 are mediated through the activation of phosphatidylinositol- 3-kinase (PI3-K) and the downstream, protein kinase B (Akt) signaling cascade. This signaling pathway increases: nitric oxide (NO) production by endothelial cells (EC), vascular smooth muscle cell (VSMC)- sodium pump (Na +, K+-ATPase) and myosin bound phosphatase (MBP) activity and GLU transport in skeletal muscle and adipocytes. Thus, functional alterations in these INS/ IGF-1 signaling pathways are likely to play an important role in these pathologies. In this regard, there is emerging evidence that angiotensin II (Ang II) interferes with this signaling, resulting in a state of resistance to INS/ IGF-1 mediated vasorelaxation and GLU transport; however, the role of intermediary signaling molecules are unclear. We hypothesize that Ang II exerts antagonistic effects on INS / IGF-l-stimulated PI3-K/Akt signaling through the generation of reactive oxygen species (ROS) and activation of RhoA. Further, it is proposed that in states of lNS/ IGF-1 resistance and hypertension there is exaggerated tissue Ang II mediated generation of ROS, and activation of RhoA. To test the main hypothesis and its corollary, we will address the following 2 specific aims: 1. To determine the role of RhoA and ROS in mediating the inhibitory effects of Ang II on the Akt-mediated actions of INS and IGF-1 involved in NO metabolism in EC; VSMC Na+,K+-ATPase; MBP activation; and also in the potentiation of GLU transport in skeletal muscle and adipose tissue. 2. To ascertain the role or Ang H-mediated RhoA/ROS stimulation in the impairment of GLU disposal and vasorelaxation in INS-resistant and Ang II overexpressing rodent models of hypertension. Using primary cultures of EC and VSMC, we will examine the role of Ang II-stimulated RhoA and ROS on NO metabolism in EC and VSMC Na +, K+-ATPase and MBP activity. To delineate the role of Akt, RhoA, and ROS signaling in mediating the counterregulatory actions of Ang II and INS/ IGF-1, we will interrupt each of these signaling pathways by transfecting VSMC with dominant negative constructs of Akt and RhoA, and antisense expression of p22phox, one of the critical components of NAD(P)H oxidase. We will profile and quantify site-specific phosphorylation and ROS-induced posttranslational modifications of the signaling molecules (i.e., Akt, RhoA, phoxes) and enzymes (i.e., eNOS, sodium pump, MBP) using liquid chromatography-tandem mass spectrometry. These studies will be complemented with in vivo and ex vivo studies of vasculature and skeletal muscle/adipocytes in rodent models of hypertension and INS resistance as well as normotensive controls. This proposed investigation should significantly enhance our knowledge regarding the role of Ang II in the pathogenesis of INS resistance and hypertension

胰岛素（INS）耐药性和高血压经常共存，并经常发展为糖尿病和心血管疾病。 INS及其在结构和功能上相似的肽，胰岛素样生长因子（IGF-1），都证明均可促进血管延缓以及葡萄糖（GLU）处置。我们实验室中的最新研究表明，INS/ IGF-1的这些作用是通过激活磷脂酰肌醇3-激酶（PI3-K）和下游蛋白激酶B（AKT）信号级联介导的。该信号通路增加：内皮细胞（EC），血管平滑肌细胞（VSMC） - 钠泵（Na +，K +-ATPase）和肌球蛋白结合的磷酸酶（MBP）活性以及骨骼肌肌肉和脂肪细胞中GLU转运的钠泵（Na +，K +-ATPase）和GLU转运。因此，这些INS/ IGF-1信号通路中的功能改变可能在这些病理中起重要作用。在这方面，有新兴的证据表明血管紧张素II（ANG II）会干扰这种信号，从而导致对INS/ IGF-1介导的血管延缓和GLU转运的抗性；但是，中间信号分子的作用尚不清楚。我们假设ANG II通过产生活性氧（ROS）和RhoA的激活来对INS / IGF-L-刺激的PI3-K / AKT信号发挥拮抗作用。此外，有人提出，在LNS/ IGF-1耐药性和高血压状态下，有夸张的组织ANG II介导的ROS产生和RhoA的激活。为了检验主要假设及其推论，我们将解决以下两个特定目的：1。确定RhoA和ROS在介导ANG II对INS和IGF-1对EC无代谢无代谢的INS和IGF-1的抑制作用中的作用； VSMC Na+，K+-ATPase; MBP激活；以及在骨骼肌和脂肪组织中GLU转运的增强。 2。确定在耐药和ANG II中过表达高血压啮齿动物模型中GLU处置和血管延缓损害中的作用或ANG H介导的RhoA/ROS刺激。使用EC和VSMC的一级培养物，我们将研究ANG II刺激的RhoA和ROS在EC和VSMC Na +，K +-ATPase和MBP活性中无代谢的作用。为了描述AKT，RhoA和ROS信号在介导ANG II和INS/ INS/ IGF-1的反调节作用中的作用，我们将通过转染Akt和RhoA的主要负面构建体的VSMC来中断这些信号传导途径，以及P22Phox的反义表达，P22Phox的反义表达，其中一种是nAdAd的批量组合（P22Phox）。我们将使用液态色谱量表质谱法对位点特异性磷酸化和ROS诱导的信号分子（即Akt，RhoA，Phoxes）和酶（即eNOS，钠泵，MBP）的转换后修饰。这些研究将与体内的体内和离体研究相辅相成，对高血压和INS耐药性以及正常控制控制的啮齿动物模型中的脉管和骨骼肌/脂肪细胞进行了补充。该提出的研究应显着增强我们对Ang II在INS抗性和高血压发病机理中的作用的了解