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Rojas S, Basualto E, Valdivia L, Vallejos N, Ceballos K, Peña E, Rivas C, Nualart F, Guzmán-Gutiérrez E, Escudero C, Toledo F, Sobrevia L, Cid M, González M. The activity of IKCa and BKCa channels contributes to insulin-mediated NO synthesis and vascular tone regulation in human umbilical vein. Nitric Oxide 2020; 99:7-16. [PMID: 32165314 DOI: 10.1016/j.niox.2020.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/23/2020] [Accepted: 03/03/2020] [Indexed: 01/16/2023]
Abstract
Insulin regulates the l-arginine/nitric oxide (NO) pathway in human umbilical vein endothelial cells (HUVECs), increasing the plasma membrane expression of the l-arginine transporter hCAT-1 and inducing vasodilation in umbilical and placental veins. Placental vascular relaxation induced by insulin is dependent of large conductance calcium-activated potassium channels (BKCa), but the role of KCa channels on l-arginine transport and NO synthesis is still unknown. The aim of this study was to determine the contribution of KCa channels in both insulin-induced l-arginine transport and NO synthesis, and its relationship with placental vascular relaxation. HUVECs, human placental vein endothelial cells (HPVECs) and placental veins were freshly isolated from umbilical cords and placenta from normal pregnancies. Cells or tissue were incubated in absence or presence of insulin and/or tetraethylammonium, 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole, iberiotoxin or NG-nitro-l-arginine methyl ester. l-Arginine uptake, plasma membrane polarity, NO levels, hCAT-1 expression and placenta vascular reactivity were analyzed. The inhibition of intermediate-conductance KCa (IKCa) and BKCa increases l-arginine uptake, which was related with protein abundance of hCAT-1 in HUVECs. IKCa and BKCa activities contribute to NO-synthesis induced by insulin but are not directly involved in insulin-stimulated l-arginine uptake. Long term incubation (8 h) with insulin increases the plasma membrane hyperpolarization and hCAT-1 expression in HUVECs and HPVECs. Insulin-induced relaxation in placental vasculature was reversed by KCa inhibition. The results show that the activity of IKCa and BKCa channels are relevant for both physiological regulations of NO synthesis and vascular tone regulation in the human placenta, acting as a part of negative feedback mechanism for autoregulation of l-arginine transport in HUVECs.
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Affiliation(s)
- Susana Rojas
- Laboratorio de Fisiología Vascular, Departamento de Fisiología, Facultad de Ciencias Biológicas, Universidad deConcepción, Concepción, Chile
| | - Emerita Basualto
- Laboratorio de Fisiología Vascular, Departamento de Fisiología, Facultad de Ciencias Biológicas, Universidad deConcepción, Concepción, Chile
| | - Luz Valdivia
- Laboratorio de Fisiología Vascular, Departamento de Fisiología, Facultad de Ciencias Biológicas, Universidad deConcepción, Concepción, Chile
| | - Natalia Vallejos
- Laboratorio de Fisiología Vascular, Departamento de Fisiología, Facultad de Ciencias Biológicas, Universidad deConcepción, Concepción, Chile; Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Karen Ceballos
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Eduardo Peña
- Departmento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Coralia Rivas
- Departmento de Fisiopatología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Francisco Nualart
- Departamento de Biología Celular, Laboratorio de Neurobiología y Células Madres Neuro-CellTT, Centro de Microscopía Avanzada CMA BIOBIO, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Enrique Guzmán-Gutiérrez
- Departamento de Bioquímica Clínica e Inmunología, Facultad de Farmacia, Universidad de Concepción, Concepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS), Chillán, Chile
| | - Carlos Escudero
- Group of Research and Innovation in Vascular Health (GRIVAS), Chillán, Chile; Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Department of Basic Sciences, Universidad del Bío-Bío, Chillán, Chile
| | - Fernando Toledo
- Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile; Cellular and Molecular Physiology Laboratory (CMPL), Department of Obstetrics, Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Department of Obstetrics, Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile; Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, Spain; University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston QLD, Queensland, Australia
| | - Marcela Cid
- Departmento de Obstetricia y Puericultura, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Marcelo González
- Laboratorio de Fisiología Vascular, Departamento de Fisiología, Facultad de Ciencias Biológicas, Universidad deConcepción, Concepción, Chile; Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS), Chillán, Chile.
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Silva L, Subiabre M, Araos J, Sáez T, Salsoso R, Pardo F, Leiva A, San Martín R, Toledo F, Sobrevia L. Insulin/adenosine axis linked signalling. Mol Aspects Med 2017; 55:45-61. [DOI: 10.1016/j.mam.2016.11.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 12/22/2022]
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Shimomura T, Nakano T, Goto K, Wakabayashi I. R59949, a diacylglycerol kinase inhibitor, inhibits inducible nitric oxide production through decreasing transplasmalemmal L-arginine uptake in vascular smooth muscle cells. Naunyn Schmiedebergs Arch Pharmacol 2016; 390:207-214. [PMID: 27909743 DOI: 10.1007/s00210-016-1316-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 11/14/2016] [Indexed: 01/26/2023]
Abstract
Although diacylglycerol kinase (DGK) is known to be expressed in vascular smooth muscle cell, its functional significance remains to be clarified. We hypothesized that DGK is involved in the pathway of cytokine-induced nitric oxide (NO) production in vascular smooth muscle cells. The purpose of this study was to investigate the effects of R59949, a diacylglycerol kinase inhibitor, on inducible nitric oxide production in vascular smooth muscle cell. Cultured rat aortic smooth muscle cells (RASMCs) were used to elucidate the effects of R59949 on basal and interleukin-1β (IL-1β)-induced NO production. The effects of R59949 on protein and mRNA expression of induced nitric oxide synthase (iNOS) and on transplasmalemmal L-arginine uptake were also evaluated using RASMCs. Treatment of RASMCs with R59949 (10 μM) inhibited IL-1β (10 ng/ml)-induced NO production but not basal NO production. Neither protein nor mRNA expression level of iNOS after stimulation with IL-1β was significantly affected by R59949. Estimated enzymatic activities of iNOS in RASMCs were comparable in the absence and presence of R59949. Stimulation of RASMCs with IL-1β caused a marked increase in transplasmalemmal L-arginine uptake into RASMCs. L-Arginine uptake in the presence of IL-1β was markedly inhibited by R59949, while basal L-arginine uptake was not significantly affected by R59949. Both IL-1β-induced NO production and L-arginine uptake were abolished in the presence of cycloheximide (1 μM). The results indicate that R59949 inhibits inducible NO production through decreasing transplasmalemmal L-arginine uptake. DGK is suggested to be involved in cytokine-stimulated L-arginine transport and regulate its intracellular concentration in vascular smooth muscle cell.
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Affiliation(s)
- Tomoko Shimomura
- Department of Environmental and Preventive Medicine, Hyogo College of Medicine, Mukogawa-cho 1-1, Nishinomiya, Hyogo, 663-8501, Japan
| | - Tomoyuki Nakano
- Department of Anatomy and Cell Biology, Yamagata University Faculty of Medicine, Iida-nishi 2-2-2, Yamagata, 990-9585, Japan
| | - Kaoru Goto
- Department of Anatomy and Cell Biology, Yamagata University Faculty of Medicine, Iida-nishi 2-2-2, Yamagata, 990-9585, Japan
| | - Ichiro Wakabayashi
- Department of Environmental and Preventive Medicine, Hyogo College of Medicine, Mukogawa-cho 1-1, Nishinomiya, Hyogo, 663-8501, Japan.
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Protein kinase C phosphorylates AMP-activated protein kinase α1 Ser487. Biochem J 2016; 473:4681-4697. [PMID: 27784766 PMCID: PMC5147050 DOI: 10.1042/bcj20160211] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 10/23/2016] [Accepted: 10/25/2016] [Indexed: 12/16/2022]
Abstract
The key metabolic regulator, AMP-activated protein kinase (AMPK), is reported to be down-regulated in metabolic disorders, but the mechanisms are poorly characterised. Recent studies have identified phosphorylation of the AMPKα1/α2 catalytic subunit isoforms at Ser487/491, respectively, as an inhibitory regulation mechanism. Vascular endothelial growth factor (VEGF) stimulates AMPK and protein kinase B (Akt) in cultured human endothelial cells. As Akt has been demonstrated to be an AMPKα1 Ser487 kinase, the effect of VEGF on inhibitory AMPK phosphorylation in cultured primary human endothelial cells was examined. Stimulation of endothelial cells with VEGF rapidly increased AMPKα1 Ser487 phosphorylation in an Akt-independent manner, without altering AMPKα2 Ser491 phosphorylation. In contrast, VEGF-stimulated AMPKα1 Ser487 phosphorylation was sensitive to inhibitors of protein kinase C (PKC) and PKC activation using phorbol esters or overexpression of PKC-stimulated AMPKα1 Ser487 phosphorylation. Purified PKC and Akt both phosphorylated AMPKα1 Ser487 in vitro with similar efficiency. PKC activation was associated with reduced AMPK activity, as inhibition of PKC increased AMPK activity and phorbol esters inhibited AMPK, an effect lost in cells expressing mutant AMPKα1 Ser487Ala. Consistent with a pathophysiological role for this modification, AMPKα1 Ser487 phosphorylation was inversely correlated with insulin sensitivity in human muscle. These data indicate a novel regulatory role of PKC to inhibit AMPKα1 in human cells. As PKC activation is associated with insulin resistance and obesity, PKC may underlie the reduced AMPK activity reported in response to overnutrition in insulin-resistant metabolic and vascular tissues.
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Dubó S, Gallegos D, Cabrera L, Sobrevia L, Zúñiga L, González M. Cardiovascular Action of Insulin in Health and Disease: Endothelial L-Arginine Transport and Cardiac Voltage-Dependent Potassium Channels. Front Physiol 2016; 7:74. [PMID: 27014078 PMCID: PMC4791397 DOI: 10.3389/fphys.2016.00074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 02/15/2016] [Indexed: 12/19/2022] Open
Abstract
Impairment of insulin signaling on diabetes mellitus has been related to cardiovascular dysfunction, heart failure, and sudden death. In human endothelium, cationic amino acid transporter 1 (hCAT-1) is related to the synthesis of nitric oxide (NO) and insulin has a vascular effect in endothelial cells through a signaling pathway that involves increases in hCAT-1 expression and L-arginine transport. This mechanism is disrupted in diabetes, a phenomenon potentiated by excessive accumulation of reactive oxygen species (ROS), which contribute to lower availability of NO and endothelial dysfunction. On the other hand, electrical remodeling in cardiomyocytes is considered a key factor in heart failure progression associated to diabetes mellitus. This generates a challenge to understand the specific role of insulin and the pathways involved in cardiac function. Studies on isolated mammalian cardiomyocytes have shown prolongated action potential in ventricular repolarization phase that produces a long QT interval, which is well explained by attenuation in the repolarizing potassium currents in cardiac ventricles. Impaired insulin signaling causes specific changes in these currents, such a decrease amplitude of the transient outward K(+) (Ito) and the ultra-rapid delayed rectifier (IKur) currents where, together, a reduction of mRNA and protein expression levels of α-subunits (Ito, fast; Kv 4.2 and IKs; Kv 1.5) or β-subunits (KChIP2 and MiRP) of K(+) channels involved in these currents in a MAPK mediated pathway process have been described. These results support the hypothesis that lack of insulin signaling can produce an abnormal repolarization in cardiomyocytes. Furthermore, the arrhythmogenic potential due to reduced Ito current can contribute to an increase in the incidence of sudden death in heart failure. This review aims to show, based on pathophysiological models, the regulatory function that would have insulin in vascular system and in cardiac electrophysiology.
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Affiliation(s)
- Sebastián Dubó
- Department of Kinesiology, Faculty of Medicine, Universidad de Concepción Concepción, Chile
| | - David Gallegos
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Lissette Cabrera
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Department of Morphophysiology, Faculty of Medicine, Universidad Diego PortalesSantiago, Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynecology, Faculty of Medicine, School of Medicine, Pontificia Universidad Católica de ChileSantiago, Chile; Department of Physiology, Faculty of Pharmacy, Universidad de SevillaSeville, Spain; Faculty of Medicine and Biomedical Sciences, University of Queensland Centre for Clinical Research (UQCCR), University of QueenslandHerston, QLD, Queensland, Australia
| | - Leandro Zúñiga
- Centro de Investigaciones Médicas, Escuela de Medicina, Universidad de Talca Talca, Chile
| | - Marcelo González
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS-Health)Chillán, Chile
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González M, Rojas S, Avila P, Cabrera L, Villalobos R, Palma C, Aguayo C, Peña E, Gallardo V, Guzmán-Gutiérrez E, Sáez T, Salsoso R, Sanhueza C, Pardo F, Leiva A, Sobrevia L. Insulin reverses D-glucose-increased nitric oxide and reactive oxygen species generation in human umbilical vein endothelial cells. PLoS One 2015; 10:e0122398. [PMID: 25875935 PMCID: PMC4397070 DOI: 10.1371/journal.pone.0122398] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 02/23/2015] [Indexed: 01/14/2023] Open
Abstract
Vascular tone is controlled by the L-arginine/nitric oxide (NO) pathway, and NO bioavailability is strongly affected by hyperglycaemia-induced oxidative stress. Insulin leads to high expression and activity of human cationic amino acid transporter 1 (hCAT-1), NO synthesis and vasodilation; thus, a protective role of insulin on high D-glucose-alterations in endothelial function is likely. Vascular reactivity to U46619 (thromboxane A2 mimetic) and calcitonin gene related peptide (CGRP) was measured in KCl preconstricted human umbilical vein rings (wire myography) incubated in normal (5 mmol/L) or high (25 mmol/L) D-glucose. hCAT-1, endothelial NO synthase (eNOS), 42 and 44 kDa mitogen-activated protein kinases (p42/44mapk), protein kinase B/Akt (Akt) expression and activity were determined by western blotting and qRT-PCR, tetrahydrobiopterin (BH4) level was determined by HPLC, and L-arginine transport (0-1000 μmol/L) was measured in response to 5-25 mmol/L D-glucose (0-36 hours) in passage 2 human umbilical vein endothelial cells (HUVECs). Assays were in the absence or presence of insulin and/or apocynin (nicotinamide adenine dinucleotide phosphate-oxidase [NADPH oxidase] inhibitor), tempol or Mn(III)TMPyP (SOD mimetics). High D-glucose increased hCAT-1 expression and activity, which was biphasic (peaks: 6 and 24 hours of incubation). High D-glucose-increased maximal transport velocity was blocked by insulin and correlated with lower hCAT-1 expression and SLC7A1 gene promoter activity. High D-glucose-increased transport parallels higher reactive oxygen species (ROS) and superoxide anion (O2•-) generation, and increased U46619-contraction and reduced CGRP-dilation of vein rings. Insulin and apocynin attenuate ROS and O2•- generation, and restored vascular reactivity to U46619 and CGRP. Insulin, but not apocynin or tempol reversed high D-glucose-increased NO synthesis; however, tempol and Mn(III)TMPyP reversed the high D-glucose-reduced BH4 level. Insulin and tempol blocked the high D-glucose-increased p42/44mapk phosphorylation. Vascular dysfunction caused by high D-glucose is likely attenuated by insulin through the L-arginine/NO and O2•-/NADPH oxidase pathways. These findings are of interest for better understanding vascular dysfunction in states of foetal insulin resistance and hyperglycaemia.
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Affiliation(s)
- Marcelo González
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
- Group of Research and Innovation in Vascular Health (GRIVAS-Health), PO-Box 114-D, Chillán 3800708, Chile
| | - Susana Rojas
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
| | - Pía Avila
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
| | - Lissette Cabrera
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
- Department of Morphophysiology, Faculty of Medicine, Universidad Diego Portales, Santiago 8370076, Chile
| | - Roberto Villalobos
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Carlos Palma
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
| | - Claudio Aguayo
- Department of Clinical Biochemistry and Immunology, Faculty of Pharmacy, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
- Group of Research and Innovation in Vascular Health (GRIVAS-Health), PO-Box 114-D, Chillán 3800708, Chile
| | - Eduardo Peña
- Department of Physiopathology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
| | - Victoria Gallardo
- Department of Physiopathology, Faculty of Biological Sciences, Universidad de Concepción, P.O. Box 160-C, Concepción 4070386, Chile
| | - Enrique Guzmán-Gutiérrez
- Group of Research and Innovation in Vascular Health (GRIVAS-Health), PO-Box 114-D, Chillán 3800708, Chile
- Faculty of Health Sciences, Universidad San Sebastián, Concepción 4080871, Chile
| | - Tamara Sáez
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Rocío Salsoso
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Carlos Sanhueza
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
| | - Luis Sobrevia
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, QLD 4029, Queensland, Australia
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville E-41012, Spain
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago 8330024, Chile
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Abstract
A substantial body of evidence has reported that insulin has direct actions on the cardiovascular system independent of its systemic effects on plasma glucose or lipids. In particular, insulin regulates endothelial synthesis of the vasoactive mediators nitric oxide and endothelin-1, yet the importance of this in the maintenance of cardiovascular health remains poorly understood. Recent studies using animals with targeted downregulation of insulin signaling in vascular tissues are improving our understanding of the role of insulin in vascular health. This article focuses on the direct actions of insulin in cardiovascular tissues, with particular emphasis on the molecular mechanisms of insulin action on endothelial function. The potential contribution of impaired vascular insulin action to the cardiovascular complications of diabetes will also be discussed.
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Affiliation(s)
- Ian P Salt
- Institute of Cardiovascular & Medical Sciences, College of Medical, Veterinary & Life Sciences, Davidson Building, University of Glasgow, Glasgow G12 8QQ, UK.
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