151
|
Seo J, Cho DH, Lee HJ, Sung MS, Lee JY, Won KJ, Park JH, Jo I. Citron Rho-interacting kinase mediates arsenite-induced decrease in endothelial nitric oxide synthase activity by increasing phosphorylation at threonine 497: Mechanism underlying arsenite-induced vascular dysfunction. Free Radic Biol Med 2016; 90:133-44. [PMID: 26593676 DOI: 10.1016/j.freeradbiomed.2015.11.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 11/05/2015] [Accepted: 11/12/2015] [Indexed: 01/27/2023]
Abstract
We reported that arsenite causes an acute decrease in nitric oxide (NO) production by increasing phosphorylation of endothelial NO synthase at threonine 497 (eNOS-Thr(497)); however, the detailed mechanism has not yet been clarified. Here, we investigated the kinase involving in arsenite-stimulated eNOS-Thr(497) phosphorylation. Although treatment with H-89, a known protein kinase A (PKA) inhibitor, inhibited arsenite-stimulated eNOS-Thr(497) phosphorylation, no inhibition was found in cells treated with other PKA inhibitors, including Rp-8-Br-cAMPS or PKI. Based on previous reports, we also tested whether RhoA mediates arsenite-stimulated eNOS-Thr(497) phosphorylation and found that arsenite causes an acute increase in RhoA activity. Ectopic expression of dominant negative (DN)-RhoA significantly reversed arsenite-stimulated eNOS-Thr(497) phosphorylation. An in vitro phosphorylation assay also revealed that the well-known Rho effectors, Rho-associated protein kinase 1/2 (ROCK1/2), directly phosphorylate eNOS-Thr(497). Y27632, a selective ROCK inhibitor, reversed arsenite-stimulated eNOS-Thr(497) phosphorylation. However, overexpression of a small interfering RNA (siRNA) against ROCK1/2 or DN-ROCK did not reverse arsenite-stimulated eNOS-Thr(497) phosphorylation, thereby providing no conclusive evidence of a role for ROCK1/2. Knockdown of PKC-related protein kinase 1/2, another Rho effector, also did not reverse arsenite-stimulated eNOS-Thr(497) phosphorylation. In contrast, we found that transfection with an siRNA against citron Rho-interacting kinase (CRIK), the other downstream effector of Rho, significantly reversed the arsenite-induced eNOS-Thr(497) phosphorylation that was accompanied by restoration of eNOS enzymatic activity repressed by arsenite. Moreover, CRIK directly phosphorylated eNOS-Thr(497)in vitro. Finally, we also found that arsenite increased eNOS-Thr(497) phosphorylation and decreased acetylcholine-induced vessel relaxation in rat aortas. In conclusion, we demonstrate that arsenite acutely inhibits eNOS enzymatic activity and vessel relaxation in part by increasing the RhoA/CRIK/eNOS-Thr(497) phosphorylation signaling axis, which provides a molecular mechanism underlying arsenite-induced impaired vascular diseases.
Collapse
Affiliation(s)
- Jungwon Seo
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea; Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan, Chonbuk, South Korea
| | - Du-Hyong Cho
- Department of Pharmacology, School of Medicine, Eulji University, Jung-gu, Daejeon 301-746, South Korea
| | - Hyeon-Ju Lee
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea
| | - Min-Sun Sung
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea
| | - Jee Young Lee
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea
| | - Kyung-Jong Won
- Department of Medical Science, School of Medicine, Konkuk University, Chungju 380-701, South Korea
| | - Jung-Hyun Park
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea
| | - Inho Jo
- Department of Molecular Medicine, Ewha Womans University Medical School, Yangcheon-gu, Seoul 158-710, South Korea.
| |
Collapse
|
152
|
Schrauwen-Hinderling VB, Kooi ME, Schrauwen P. Mitochondrial Function and Diabetes: Consequences for Skeletal and Cardiac Muscle Metabolism. Antioxid Redox Signal 2016; 24:39-51. [PMID: 25808308 DOI: 10.1089/ars.2015.6291] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SIGNIFICANCE An early hallmark in the development of type 2 diabetes is the resistance to the effect of insulin in skeletal muscle and in the heart. Since mitochondrial function was found to be diminished in patients with type 2 diabetes, it was suggested that this defect might be involved in the etiology of insulin resistance. Although several hypotheses were suggested, yet unclear is the mechanistic link between these two phenomena. RECENT ADVANCES Herein, we review the evidence for disturbances in mitochondrial function in skeletal muscle and the heart in the diabetic state. Also the mechanisms involved in improving mitochondrial function are considered and, whenever possible, human data is cited. CRITICAL ISSUES Reported evidence shows that interventions that improve skeletal muscle mitochondrial function also improve insulin sensitivity in humans. In the heart, available data from animal studies suggests that enhancement of mitochondrial function can reverse aging-induced changes in heart function, and can be protective against cardiomyopathy and heart failure. FUTURE DIRECTIONS Mitochondria and their functions can be targeted with the aim of improving skeletal muscle insulin sensitivity and cardiac function. However, human clinical intervention studies are needed to fully substantiate the potential of mitochondria as a target to prevent cardiometabolic disease.
Collapse
Affiliation(s)
- Vera B Schrauwen-Hinderling
- 1 Department of Radiology, Maastricht University Medical Center , Maastricht, The Netherlands .,2 Department of Human Biology, Maastricht University Medical Center , Maastricht, The Netherlands .,3 Department of NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center , Maastricht, The Netherlands
| | - Marianne Eline Kooi
- 1 Department of Radiology, Maastricht University Medical Center , Maastricht, The Netherlands .,3 Department of NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center , Maastricht, The Netherlands .,4 Department of CARIM School for Cardiovascular Diseases in Maastricht, Maastricht University Medical Center , Maastricht, The Netherlands
| | - Patrick Schrauwen
- 2 Department of Human Biology, Maastricht University Medical Center , Maastricht, The Netherlands .,3 Department of NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center , Maastricht, The Netherlands
| |
Collapse
|
153
|
Daskalopoulos EP, Dufeys C, Beauloye C, Bertrand L, Horman S. AMPK in Cardiovascular Diseases. EXPERIENTIA SUPPLEMENTUM (2012) 2016; 107:179-201. [PMID: 27812981 DOI: 10.1007/978-3-319-43589-3_8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This chapter summarizes the implication of AMP-activated protein kinase (AMPK) in the regulation of various physiological and pathological cellular events of great importance for the maintenance of cardiac function. These include the control of both metabolic and non-metabolic elements targeting the different cellular components of the cardiac tissue, i.e., cardiomyocytes, fibroblasts, and vascular cells. The description of the multifaceted action of the two AMPK catalytic isoforms, α1 and α2, emphasizes the general protective action of this protein kinase against the development of critical pathologies like myocardial ischemia, cardiac hypertrophy, diabetic cardiomyopathy, and heart failure.
Collapse
Affiliation(s)
- Evangelos P Daskalopoulos
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium.,Cardiovascular Research (Care) Institute, Athens, Ioannina, Greece
| | - Cécile Dufeys
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| | - Christophe Beauloye
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium.,Division of Cardiology, Cliniques universitaires Saint-Luc, Brussels, Belgium
| | - Luc Bertrand
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium.
| | - Sandrine Horman
- Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Brussels, Belgium
| |
Collapse
|
154
|
Hwang S, Lee HJ, Kim G, Won KJ, Park YS, Jo I. CCN1 acutely increases nitric oxide production via integrin αvβ3-Akt-S6K-phosphorylation of endothelial nitric oxide synthase at the serine 1177 signaling axis. Free Radic Biol Med 2015; 89:229-40. [PMID: 26393424 DOI: 10.1016/j.freeradbiomed.2015.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 07/14/2015] [Accepted: 08/05/2015] [Indexed: 11/30/2022]
Abstract
Although CCN1 (also known as cysteine-rich, angiogenic inducer 61, CYR61) has been reported to promote angiogenesis and neovascularization in endothelial cells (ECs), its effects on endothelial nitric oxide (NO) production have never been studied. Using human umbilical vein ECs, we investigated whether and how CCN1 regulates NO production. CCN1 acutely increased NO production in a time- and dose-dependent manner, which was accompanied by increased phosphorylation of endothelial NO synthase (eNOS) at serine 1177 (eNOS-Ser(1177)), but not that of eNOS-Thr(495) or eNOS-Ser(114). The level of total eNOS expression was unaltered. Treatment with either LY294002, a selective inhibitor of phosphoinositide 3-kinase known as an upstream kinase of Akt, or H-89, an inhibitor of protein kinase A, mitogen- and stress-activated protein kinase 1, Rho-associated protein kinase 2, and ribosomal protein S6 kinase (S6K), inhibited CCN1-stimulated eNOS-Ser(1177) phosphorylation and subsequent NO production. Ectopic expression of small interfering RNA against Akt and S6K significantly inhibited the effects of CCN1. Consistently, CCN1 increased the phosphorylation of Akt-Ser(473) and S6K-Thr(389). However, CCN1 did not alter the expression or secretion of VEGF, a known downstream factor of CCN1 and a potential upstream factor of Akt-mediated eNOS-Ser(1177) phosphorylation. Furthermore, neutralization of integrin αvβ3 with corresponding antibody completely reversed all of the observed effects of CCN1. Moreover, CCN1 increased acetylcholine-induced relaxation in the rat aortas. Finally, we also found that CCN1-stimulated eNOS-Ser(1177) phosphorylation and NO production are true for other types of EC tested. In conclusion, CCN1 acutely increases NO production via activation of a signaling axis in integrin αvβ3-Akt-S6K-eNOS-Ser(1177) phosphorylation, suggesting an important role for CCN1 in vasodilation.
Collapse
Affiliation(s)
- Soojin Hwang
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710, Republic of Korea
| | - Hyeon-Ju Lee
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710, Republic of Korea
| | - Gyungah Kim
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710, Republic of Korea
| | - Kyung-Jong Won
- Department of Medical Science, School of Medicine, Konkuk University, Chungju 380-701, Republic of Korea
| | - Yoon Shin Park
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710, Republic of Korea
| | - Inho Jo
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710, Republic of Korea.
| |
Collapse
|
155
|
Shu X, Keller TCS, Begandt D, Butcher JT, Biwer L, Keller AS, Columbus L, Isakson BE. Endothelial nitric oxide synthase in the microcirculation. Cell Mol Life Sci 2015; 72:4561-75. [PMID: 26390975 PMCID: PMC4628887 DOI: 10.1007/s00018-015-2021-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/21/2015] [Accepted: 08/11/2015] [Indexed: 02/07/2023]
Abstract
Endothelial nitric oxide synthase (eNOS, NOS3) is responsible for producing nitric oxide (NO)--a key molecule that can directly (or indirectly) act as a vasodilator and anti-inflammatory mediator. In this review, we examine the structural effects of regulation of the eNOS enzyme, including post-translational modifications and subcellular localization. After production, NO diffuses to surrounding cells with a variety of effects. We focus on the physiological role of NO and NO-derived molecules, including microvascular effects on vessel tone and immune response. Regulation of eNOS and NO action is complicated; we address endogenous and exogenous mechanisms of NO regulation with a discussion of pharmacological agents used in clinical and laboratory settings and a proposed role for eNOS in circulating red blood cells.
Collapse
Affiliation(s)
- Xiaohong Shu
- College of Pharmacy, Dalian Medical University, Dalian, 116044, China
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
| | - T C Stevenson Keller
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, USA
| | - Daniela Begandt
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
| | - Joshua T Butcher
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
| | - Lauren Biwer
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, USA
| | - Alexander S Keller
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, USA
| | - Linda Columbus
- Department of Chemistry, University of Virginia, Charlottesville, USA
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VA, 22908, USA.
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, USA.
| |
Collapse
|
156
|
Donato AJ, Morgan RG, Walker AE, Lesniewski LA. Cellular and molecular biology of aging endothelial cells. J Mol Cell Cardiol 2015; 89:122-35. [PMID: 25655936 PMCID: PMC4522407 DOI: 10.1016/j.yjmcc.2015.01.021] [Citation(s) in RCA: 326] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 01/05/2015] [Accepted: 01/27/2015] [Indexed: 12/29/2022]
Abstract
Cardiovascular disease (CVD) is the leading cause of death in the United States and aging is a major risk factor for CVD development. One of the major age-related arterial phenotypes thought to be responsible for the development of CVD in older adults is endothelial dysfunction. Endothelial function is modulated by traditional CVD risk factors in young adults, but advancing age is independently associated with the development of vascular endothelial dysfunction. This endothelial dysfunction results from a reduction in nitric oxide bioavailability downstream of endothelial oxidative stress and inflammation that can be further modulated by traditional CVD risk factors in older adults. Greater endothelial oxidative stress with aging is a result of augmented production from the intracellular enzymes NADPH oxidase and uncoupled eNOS, as well as from mitochondrial respiration in the absence of appropriate increases in antioxidant defenses as regulated by relevant transcription factors, such as FOXO. Interestingly, it appears that NFkB, a critical inflammatory transcription factor, is sensitive to this age-related endothelial redox change and its activation induces transcription of pro-inflammatory cytokines that can further suppress endothelial function, thus creating a vicious feed-forward cycle. This review will discuss the two macro-mechanistic processes, oxidative stress and inflammation, that contribute to endothelial dysfunction with advancing age as well as the cellular and molecular events that lead to the vicious cycle of inflammation and oxidative stress in the aged endothelium. Other potential mediators of this pro-inflammatory endothelial phenotype are increases in immune or senescent cells in the vasculature. Of note, genomic instability, telomere dysfunction or DNA damage has been shown to trigger cell senescence via the p53/p21 pathway and result in increased inflammatory signaling in arteries from older adults. This review will discuss the current state of knowledge regarding the emerging concepts of senescence and genomic instability as mechanisms underlying oxidative stress and inflammation in the aged endothelium. Lastly, energy sensitive/stress resistance pathways (SIRT-1, AMPK, mTOR) are altered in endothelial cells and/or arteries with aging and these pathways may modulate endothelial function via key oxidative stress and inflammation-related transcription factors. This review will also discuss what is known about the role of "energy sensing" longevity pathways in modulating endothelial function with advancing age. With the growing population of older adults, elucidating the cellular and molecular mechanisms of endothelial dysfunction with age is critical to establishing appropriate and measured strategies to utilize pharmacological and lifestyle interventions aimed at alleviating CVD risk. This article is part of a Special Issue entitled "SI: CV Aging".
Collapse
Affiliation(s)
- Anthony J Donato
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA; Veteran's Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, UT, USA.
| | - R Garrett Morgan
- University of Washington, Department of Pathology, Seattle, WA, USA
| | - Ashley E Walker
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA
| | - Lisa A Lesniewski
- University of Utah, Department of Internal Medicine, Division of Geriatrics, Salt Lake City, UT, USA; Veteran's Affairs Medical Center-Salt Lake City, Geriatrics Research Education and Clinical Center, Salt Lake City, UT, USA
| |
Collapse
|
157
|
Mukohda M, Stump M, Ketsawatsomkron P, Hu C, Quelle FW, Sigmund CD. Endothelial PPAR-γ provides vascular protection from IL-1β-induced oxidative stress. Am J Physiol Heart Circ Physiol 2015; 310:H39-48. [PMID: 26566726 DOI: 10.1152/ajpheart.00490.2015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 11/09/2015] [Indexed: 11/22/2022]
Abstract
Loss of peroxisome proliferator-activated receptor (PPAR)-γ function in the vascular endothelium enhances atherosclerosis and NF-κB target gene expression in high-fat diet-fed apolipoprotein E-deficient mice. The mechanisms by which endothelial PPAR-γ regulates inflammatory responses and protects against atherosclerosis remain unclear. To assess functional interactions between PPAR-γ and inflammation, we used a model of IL-1β-induced aortic dysfunction in transgenic mice with endothelium-specific overexpression of either wild-type (E-WT) or dominant negative PPAR-γ (E-V290M). IL-1β dose dependently decreased IκB-α, increased phospho-p65, and increased luciferase activity in the aorta of NF-κB-LUC transgenic mice. IL-1β also dose dependently reduced endothelial-dependent relaxation by ACh. The loss of ACh responsiveness was partially improved by pretreatment of the vessels with the PPAR-γ agonist rosiglitazone or in E-WT. Conversely, IL-1β-induced endothelial dysfunction was worsened in the aorta from E-V290M mice. Although IL-1β increased the expression of NF-κB target genes, NF-κB p65 inhibitor did not alleviate endothelial dysfunction induced by IL-1β. Tempol, a SOD mimetic, partially restored ACh responsiveness in the IL-1β-treated aorta. Notably, tempol only modestly improved protection in the E-WT aorta but had an increased protective effect in the E-V290M aorta compared with the aorta from nontransgenic mice, suggesting that PPAR-γ-mediated protection involves antioxidant effects. IL-1β increased ROS and decreased the phospho-endothelial nitric oxide synthase (Ser(1177))-to-endothelial nitric oxide synthase ratio in the nontransgenic aorta. These effects were completely abolished in the aorta with endothelial overexpression of WT PPAR-γ but were worsened in the aorta with E-V290M even in the absence of IL-1β. We conclude that PPAR-γ protects against IL-1β-mediated endothelial dysfunction through a reduction of oxidative stress responses but not by blunting IL-1β-mediated NF-κB activity.
Collapse
Affiliation(s)
- Masashi Mukohda
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Madeliene Stump
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Pimonrat Ketsawatsomkron
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Chunyan Hu
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Frederick W Quelle
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Curt D Sigmund
- Department of Pharmacology, Center for Hypertension Research, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| |
Collapse
|
158
|
Jian MY, Liu Y, Li Q, Wolkowicz P, Alexeyev M, Zmijewski J, Creighton J. N-cadherin coordinates AMP kinase-mediated lung vascular repair. Am J Physiol Lung Cell Mol Physiol 2015; 310:L71-85. [PMID: 26545901 DOI: 10.1152/ajplung.00227.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 10/30/2015] [Indexed: 01/24/2023] Open
Abstract
Injury to the pulmonary circulation compromises endothelial barrier function and increases lung edema. Resolution of lung damage involves restoring barrier integrity, a process requiring reestablishment of endothelial cell-cell adhesions. However, mechanisms underlying repair in lung endothelium are poorly understood. In pulmonary microvascular endothelium, AMP kinase α1 (AMPKα1) stimulation enhances recovery of the endothelial barrier after LPS-induced vascular damage. AMPKα1 colocalizes to a discrete membrane compartment with the adhesion protein neuronal cadherin (N-cadherin). This study sought to determine N-cadherin's role in the repair process. Short-hairpin RNA against full-length N-cadherin or a C-terminally truncated N-cadherin, designed to disrupt the cadherin's interactions with intracellular proteins, were expressed in lung endothelium. Disruption of N-cadherin's intracellular domain caused translocation of AMPK away from the membrane and attenuated AMPK-mediated restoration of barrier function in LPS-treated endothelium. AMPK activity measurements indicated that lower basal AMPK activity in cells expressing the truncated N-cadherin compared with controls. Moreover, the AMPK stimulator 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) failed to increase AMPK activity in cells expressing the modified N-cadherin, indicating uncoupling of a functional association between AMPK and the cadherin. Isolated lung studies confirmed a physiologic role for this pathway in vivo. AMPK activation reversed LPS-induced increase in permeability, whereas N-cadherin inhibition hindered AMPK-mediated repair. Thus N-cadherin coordinates the vascular protective actions of AMPK through a functional link with the kinase. This study provides insight into intrinsic repair mechanisms in the lung and supports AMPK stimulation as a modality for treating vascular disease.
Collapse
Affiliation(s)
- Ming-Yuan Jian
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Center for Lung Injury and Repair
| | - Yanping Liu
- Division of Endocrinology, Diabetes, and Metabolism
| | - Qian Li
- Division of Pediatric Neonatology, and
| | | | - Mikhail Alexeyev
- Department of Physiology and Cell Biology, Center for Lung Biology, University of South Alabama, Mobile
| | - Jaroslaw Zmijewski
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Judy Creighton
- Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Center for Lung Injury and Repair,
| |
Collapse
|
159
|
Park JH, Cho DH, Lee JY, Lee HJ, Ha Y, Ahn JH, Jo I. B56δ subunit of protein phosphatase 2A decreases phosphorylation of endothelial nitric oxide synthase at serine 116: Mechanism underlying aphidicolin-stimulated NO production. Nitric Oxide 2015; 50:46-51. [DOI: 10.1016/j.niox.2015.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/30/2015] [Accepted: 08/02/2015] [Indexed: 10/23/2022]
|
160
|
Wang L, Chen Q, Li G, Ke D. Ghrelin ameliorates impaired angiogenesis of ischemic myocardium through GHSR1a-mediated AMPK/eNOS signal pathway in diabetic rats. Peptides 2015; 73:77-87. [PMID: 26364514 DOI: 10.1016/j.peptides.2015.09.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/21/2015] [Accepted: 09/08/2015] [Indexed: 11/24/2022]
Abstract
OBJECTIVES Ghrelin, an endogenous ligand of the growth hormone secretagogue receptor (GHSR), has been found to stimulate angiogenesis in vivo and in vitro. However, the effect and the corresponding mechanisms of ghrelin on impaired myocardial angiogenesis in diabetic and myocardial infarction (MI) rat model are still unknown. METHODS In the present study, adult SD rats were randomly divided into 4 groups: control, DM, DM+ghrelin, DM+ghrelin+[D-Lys3]-GHRP-6 groups. DM was induced by streptozotocin (STZ) 60 mg/kg body weight. 12 weeks post STZ injection all groups were subjected to MI, which was induced by ligation left anterior descending artery (LAD). Ghrelin and [D-Lys3]-GHRP-6 were administered via intraperitoneal injection at the doses 200 μg/kg and 50mg/kg for 4 weeks, respectively. Left ventricular function, microvascular density (MVD), myocardial infarct size, the expression of hypoxia-inducible factor (HIF1α), vascular endothelial growth factor (VEGF), fetal liver kinase-1 (Flk-1) and fms-like tyrosine kinase-1 (Flt-1), AMPK and endothelial nitric oxide synthase (eNOS) phosphorylation were examined. RESULTS Compared with the DM group, left ventricular ejection fraction (LVEF), fractional shortening (FS), and MVD were increased, whereas myocardial infarct size decreased remarkably in DM+ghrelin group. For the mechanism study, we found that ghrelin promoted the HIF1α, VEGF, Flk-1 and Flt-1 expression, AMPK and eNOS phosphorylation in diabetic rats. However, the above biochemical events in ghrelin treated diabetic rats were completely inhibited by GHSR-1a blocker [D-Lys3]-GHRP-6. CONCLUSIONS These results suggest that administration of ghrelin ameliorates impaired angiogenesis in diabetic MI rats. And these beneficial effects derive from regulating GHSR1a-mediated AMPK/eNOS signal pathway by upregulating of HIF1α, VEGF and its receptors Flk-1, Flt-1 expressions.
Collapse
Affiliation(s)
- Li Wang
- Department of Geriatrics, the Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
| | - Qingwei Chen
- Department of Geriatrics, the Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China.
| | - Guiqiong Li
- Department of Geriatrics, the Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
| | - Dazhi Ke
- Department of Geriatrics, the Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China
| |
Collapse
|
161
|
Oliveira-Paula GH, Lacchini R, Tanus-Santos JE. Endothelial nitric oxide synthase: From biochemistry and gene structure to clinical implications of NOS3 polymorphisms. Gene 2015; 575:584-99. [PMID: 26428312 DOI: 10.1016/j.gene.2015.09.061] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 08/10/2015] [Accepted: 09/22/2015] [Indexed: 02/07/2023]
Abstract
Nitric oxide (NO) is an important vasodilator with a well-established role in cardiovascular homeostasis. While mediator is synthesized from L-arginine by neuronal, endothelial, and inducible nitric oxide synthases (NOS1,NOS3 and NOS2 respectively), NOS3 is the most important isoform for NO formation in the cardiovascular system. NOS3 is a dimeric enzyme whose expression and activity are regulated at transcriptional, posttranscriptional,and posttranslational levels. The NOS3 gene, which encodes NOS3, exhibits a number of polymorphic sites including single nucleotide polymorphisms (SNPs), variable number of tandem repeats (VNTRs), microsatellites, and insertions/deletions. Some NOS3 polymorphisms show functional effects on NOS3 expression or activity, thereby affecting NO formation. Interestingly, many studies have evaluated the effects of functional NOS3 polymorphisms on disease susceptibility and drug responses. Moreover, some studies have investigated how NOS3 haplotypes may impact endogenous NO formation and disease susceptibility. In this article,we carried out a comprehensive review to provide a basic understanding of biochemical mechanisms involved in NOS3 regulation and how genetic variations in NOS3 may translate into relevant clinical and pharmacogenetic implications.
Collapse
Affiliation(s)
- Gustavo H Oliveira-Paula
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Riccardo Lacchini
- Department of Psychiatric Nursing and Human Sciences, Ribeirao Preto College of Nursing, University of Sao Paulo, Ribeirao Preto, SP, Brazil
| | - Jose E Tanus-Santos
- Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP, Brazil.
| |
Collapse
|
162
|
Vascular nitric oxide: Beyond eNOS. J Pharmacol Sci 2015; 129:83-94. [PMID: 26499181 DOI: 10.1016/j.jphs.2015.09.002] [Citation(s) in RCA: 478] [Impact Index Per Article: 53.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 09/11/2015] [Accepted: 09/16/2015] [Indexed: 02/06/2023] Open
Abstract
As the first discovered gaseous signaling molecule, nitric oxide (NO) affects a number of cellular processes, including those involving vascular cells. This brief review summarizes the contribution of NO to the regulation of vascular tone and its sources in the blood vessel wall. NO regulates the degree of contraction of vascular smooth muscle cells mainly by stimulating soluble guanylyl cyclase (sGC) to produce cyclic guanosine monophosphate (cGMP), although cGMP-independent signaling [S-nitrosylation of target proteins, activation of sarco/endoplasmic reticulum calcium ATPase (SERCA) or production of cyclic inosine monophosphate (cIMP)] also can be involved. In the blood vessel wall, NO is produced mainly from l-arginine by the enzyme endothelial nitric oxide synthase (eNOS) but it can also be released non-enzymatically from S-nitrosothiols or from nitrate/nitrite. Dysfunction in the production and/or the bioavailability of NO characterizes endothelial dysfunction, which is associated with cardiovascular diseases such as hypertension and atherosclerosis.
Collapse
|
163
|
Li WD, Du XL, Qian AM, Hu N, Kong LS, Wei S, Li CL, Li XQ. Metformin regulates differentiation of bone marrow-derived endothelial progenitor cells via multiple mechanisms. Biochem Biophys Res Commun 2015; 465:803-9. [PMID: 26319555 DOI: 10.1016/j.bbrc.2015.08.091] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 08/20/2015] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the effect of metformin on endothelial progenitor cells (EPCs) differentiation and the possible mechanisms. METHODS EPCs were treated with metformin and differentiation, migration and tube formation of EPCs were evaluated. Moreover, we also assessed the AMPK-mTOR-p70S6K pathway, AMPK related autophagy pathway and eNOS-NO pathway to explore the mechanisms. RESULTS Metformin treatment could significantly increase differentiation of EPCs. On the mechanisms, increased level of AMPKand eNOS phosphorylation, LC3 expression and NO production, and decreased mTOR, p70 S6K as well as TGF-β expression were found in EPCs. The AMPK inhibitor compound C, Atg5 knocking-down and eNOS inhibitor l-NAME could reverse the effect exerted by metformin. CONCLUSIONS Our results here showed that metformin could regulate the differentiation of EPCs. Autophagy related pathway and AMPK-eNOS-NO pathway were involved in the mechanisms.
Collapse
Affiliation(s)
- Wen-Dong Li
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiao-Long Du
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Ai-Min Qian
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Nan Hu
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Ling-Shang Kong
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Sen Wei
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Cheng-Long Li
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiao-Qiang Li
- Department of Vascular Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China.
| |
Collapse
|
164
|
Carlström M, Liu M, Yang T, Zollbrecht C, Huang L, Peleli M, Borniquel S, Kishikawa H, Hezel M, Persson AEG, Weitzberg E, Lundberg JO. Cross-talk Between Nitrate-Nitrite-NO and NO Synthase Pathways in Control of Vascular NO Homeostasis. Antioxid Redox Signal 2015; 23:295-306. [PMID: 24224525 PMCID: PMC4523008 DOI: 10.1089/ars.2013.5481] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIMS Inorganic nitrate and nitrite from endogenous and dietary sources have emerged as alternative substrates for nitric oxide (NO) formation in addition to the classic L-arginine NO synthase (NOS)-dependent pathway. Here, we investigated a potential cross-talk between these two pathways in the regulation of vascular function. RESULTS Long-term dietary supplementation with sodium nitrate (0.1 and 1 mmol kg(-1) day(-1)) in rats caused a reversible dose-dependent reduction in phosphorylated endothelial NOS (eNOS) (Ser1177) in aorta and a concomitant increase in phosphorylation at Thr495. Moreover, eNOS-dependent vascular responses were attenuated in vessels harvested from nitrate-treated mice or when nitrite was acutely added to control vessels. The citrulline-to-arginine ratio in plasma, as a measure of eNOS activity, was reduced in nitrate-treated rodents. Telemetry measurements revealed that a low dietary nitrate dose reduced blood pressure, whereas a higher dose was associated with a paradoxical elevation. Finally, plasma cyclic guanosine monophosphate increased in mice that were treated with a low dietary nitrate dose and decreased with a higher dose. INNOVATION AND CONCLUSIONS These results demonstrate the existence of a cross-talk between the nitrate-nitrite-NO pathway and the NOS-dependent pathway in control of vascular NO homeostasis.
Collapse
Affiliation(s)
- Mattias Carlström
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden .,2 Department of Medical Cell Biology, Uppsala University , Uppsala, Sweden
| | - Ming Liu
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Ting Yang
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Christa Zollbrecht
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Liyue Huang
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden .,2 Department of Medical Cell Biology, Uppsala University , Uppsala, Sweden
| | - Maria Peleli
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Sara Borniquel
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Hiroaki Kishikawa
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Michael Hezel
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - A Erik G Persson
- 2 Department of Medical Cell Biology, Uppsala University , Uppsala, Sweden
| | - Eddie Weitzberg
- 3 Division of Anesthesiology and Intensive Care, Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| | - Jon O Lundberg
- 1 Department of Physiology and Pharmacology, Karolinska Institutet , Stockholm, Sweden
| |
Collapse
|
165
|
Abstract
Vascular development and maintenance of proper vascular function through various regulatory mechanisms are critical to our wellbeing. Delineation of the regulatory processes involved in development of the vascular system and its function is one of the most important topics in human physiology and pathophysiology. Platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), a cell adhesion molecule with proangiogenic and proinflammatory activity, has been the subject of numerous studies. In the present review, we look at the important roles that PECAM-1 and its isoforms play during angiogenesis, and its molecular mechanisms of action in the endothelium. In the endothelium, PECAM-1 not only plays a role as an adhesion molecule but also participates in intracellular signalling pathways which have an impact on various cell adhesive mechanisms and endothelial nitric oxide synthase (eNOS) expression and activity. In addition, recent studies from our laboratory have revealed an important relationship between PECAM-1 and endoglin expression. Endoglin is an essential molecule during angiogenesis, vascular development and integrity, and its expression and activity are compromised in the absence of PECAM-1. In the present review we discuss the roles that PECAM-1 isoforms may play in modulation of endothelial cell adhesive mechanisms, eNOS and endoglin expression and activity, and angiogenesis.
Collapse
|
166
|
Xing SS, Yang XY, Zheng T, Li WJ, Wu D, Chi JY, Bian F, Bai XL, Wu GJ, Zhang YZ, Zhang CT, Zhang YH, Li YS, Jin S. Salidroside improves endothelial function and alleviates atherosclerosis by activating a mitochondria-related AMPK/PI3K/Akt/eNOS pathway. Vascul Pharmacol 2015; 72:141-52. [PMID: 26187353 DOI: 10.1016/j.vph.2015.07.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 06/17/2015] [Accepted: 07/11/2015] [Indexed: 10/23/2022]
Abstract
Salidroside (SAL) is a phenylpropanoid glycoside isolated from the medicinal plant Rhodiola rosea. A recent study has reported that SAL can efficiently decrease atherosclerotic plaque formation in low-density lipoprotein receptor-deficient mice. This study was to investigate the molecular mechanism of antiatherogenic effects of SAL. Given the importance of endothelial nitric oxide synthase (eNOS) in atherosclerosis, we sought to elucidate whether SAL could stimulate eNOS activation and also to explore its upstream signaling pathway. Six-week old apoE(-/-) male mice were fed a high-fat diet for 8weeks and then were administered with SAL for another 8weeks. SAL significantly improved endothelial function associated with increasing eNOS activation, thus reduced the atherosclerotic lesion area. SAL increased eNOS-Ser1177 phosphorylation and decreased eNOS-Thr495 phosphorylation, indicative of eNOS activation in endothelium. The aortic sinus lesions in SAL treated mice displayed reduced inflammation. SAL significantly activated AMP-activated protein kinase (AMPK). Both AMPK inhibitor and AMPK small interfering RNA (siRNA) abolished SAL-induced Akt-Ser473 and eNOS-Ser1177 phosphorylation. In contrast, LY294002, the PI3k/Akt pathway inhibitor, abolished SAL-induced phosphorylation and expression of eNOS. High performance liquid chromatography (HPLC) analysis revealed that SAL decreased cellular ATP content and increased the cellular AMP/ATP ratio, which was associated with the activation of AMPK. SAL was found to decrease the mitochondrial membrane potential (ΔΨm), which is a likely consequence of reduced ATP production. The action of SAL to reduce atherosclerotic lesion formation may at least be attributed to its effect on improving endothelial function by promoting nitric oxide (NO) production, which was associated with mitochondrial depolarization and subsequent activation of the AMPK/PI3K/Akt/eNOS pathway. Taken together, our data described the effects of SAL on mitochondria, which played critical roles in improving endothelial function in atherosclerosis.
Collapse
Affiliation(s)
- Sha-Sha Xing
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Xiao-Yan Yang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Tao Zheng
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Wen-Jing Li
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Dan Wu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Jiang-Yang Chi
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Fang Bian
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Xiang-Li Bai
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Guang-Jie Wu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - You-Zhi Zhang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Cun-Tai Zhang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Yong-Hui Zhang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Yong-Sheng Li
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China
| | - Si Jin
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China; The Key Laboratory of Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan 430030, China; Department of Endocrinology, Institute of Geriatric Medicine, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430077, China.
| |
Collapse
|
167
|
Aicart-Ramos C, Rodríguez-Crespo I. Binding of PDZ domains to the carboxy terminus of inducible nitric oxide synthase boosts electron transfer and NO synthesis. FEBS Lett 2015; 589:2207-12. [PMID: 26183564 DOI: 10.1016/j.febslet.2015.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/29/2015] [Accepted: 07/02/2015] [Indexed: 10/23/2022]
Abstract
iNOS lacks any phosphorylatable residue at its C-terminus despite displaying a 25-residue extension known to block electron transfer and activity. We report that C-terminal deletions of iNOS increased the cytochrome c reduction rate. Moreover, the interaction of the iNOS C-terminus with the PDZ domains of EBP50 or CAP70 resulted not only in augmented reductase activity and greater NO synthesis but also anticipated the formation of the air-stable semiquinone generated after NADPH addition. Hence, the C-terminus of iNOS regulates the activity of the enzyme, albeit, unlike nNOS and eNOS, displacement of the autoinhibitory element occurs upon binding to proteins with PDZ domains.
Collapse
Affiliation(s)
- Clara Aicart-Ramos
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Spain
| | - Ignacio Rodríguez-Crespo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Spain.
| |
Collapse
|
168
|
Ligand activation of cannabinoid receptors attenuates hypertrophy of neonatal rat cardiomyocytes. J Cardiovasc Pharmacol 2015; 64:420-30. [PMID: 24979612 DOI: 10.1097/fjc.0000000000000134] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
: Endocannabinoids are bioactive amides, esters, and ethers of long-chain polyunsaturated fatty acids. Evidence suggests that activation of the endocannabinoid pathway offers cardioprotection against myocardial ischemia, arrhythmias, and endothelial dysfunction of coronary arteries. As cardiac hypertrophy is a convergence point of risk factors for heart failure, we determined a role for endocannabinoids in attenuating endothelin-1-induced hypertrophy and probed the signaling pathways involved. The cannabinoid receptor ligand anandamide and its metabolically stable analog, R-methanandamide, suppressed hypertrophic indicators including cardiomyocyte enlargement and fetal gene activation (ie, the brain natriuretic peptide gene) elicited by endothelin-1 in isolated neonatal rat ventricular myocytes. The ability of R-methanandamide to suppress myocyte enlargement and fetal gene activation was mediated by CB2 and CB1 receptors, respectively. Accordingly, a CB2-selective agonist, JWH-133, prevented only myocyte enlargement but not brain natriuretic peptide gene activation. A CB1/CB2 dual agonist with limited brain penetration, CB-13, inhibited both hypertrophic indicators. CB-13 activated AMP-activated protein kinase (AMPK) and, in an AMPK-dependent manner, endothelial nitric oxide synthase (eNOS). Disruption of AMPK signaling, using compound C or short hairpinRNA knockdown, and eNOS inhibition using L-NIO abolished the antihypertrophic actions of CB-13. In conclusion, CB-13 inhibits cardiomyocyte hypertrophy through AMPK-eNOS signaling and may represent a novel therapeutic approach to cardioprotection.
Collapse
|
169
|
Lau YS, Ling WC, Murugan D, Kwan CY, Mustafa MR. Endothelium-Dependent Relaxation Effect of Apocynum venetum Leaf Extract via Src/PI3K/Akt Signalling Pathway. Nutrients 2015; 7:5239-53. [PMID: 26133970 PMCID: PMC4516997 DOI: 10.3390/nu7075220] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 06/15/2015] [Accepted: 06/25/2015] [Indexed: 11/16/2022] Open
Abstract
Botanical herbs are consumed globally not only as an essential diet but also as medicines or as functional/recreational food supplements. The extract of the Apocynum venetum leaves (AVLE), also known as Luobuma, exerts its antihypertensive effect via dilating the blood vessels in an endothelium- and concentration-dependent manner with optimal effect seen at as low as 10 µg/mL. A commercial Luoboma “antihypertensive tea” is available commercially in the western province of China. The present study seeks to investigate the underlying cellular mechanisms of the nitric oxide (NO)-releasing property of AVLE in rat aortas and human umbilical vein endothelial cells (HUVECs). Endothelium-dependent relaxation induced by AVLE was assessed in organ chambers in the presence or absence of polyethyleneglycol catalase (PP2, 20 µM; inhibitor of Src kinase), wortmannin (30 nM) and LY294002 (20 µM; PI3 (phosphatidylinositol3)-Kinase inhibitor), NG-nitro-l-arginine (L-NAME, 100 µM; endothelial NO synthase inhibitor (eNOS)) and ODQ (1 µM; soluble guanylyl cyclase inhibitor). Total nitrite and nitrate (NOx) level and protein expression of p-Akt and p-eNOS were measured. AVLE-induced endothelium-dependent relaxation was reduced by PP2, wortmannin and LY294002 and abolished by L-NAME and ODQ. AVLE significantly increased total NOx level in rat aortas and in HUVECs compared to control. It also instigated phosphorylation of Akt and eNOS in cultured HUVECs in a concentration-dependent manner and this was markedly suppressed by PP2, wortmannin and LY294002. AVLE also inhibited superoxide generated from both NADPH oxidase and xanthine/xanthine oxidase system. Taken together, AVLE causes endothelium-dependent NO mediated relaxations of rat aortas through Src/PI3K/Akt dependent NO signalling pathway and possesses superoxide scavenging activity.
Collapse
Affiliation(s)
- Yeh Siang Lau
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Wei Chih Ling
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Dharmani Murugan
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| | - Chiu Yin Kwan
- Graduate Institutes of Basic Medical Sciences and Vascular Biology Group, China Medical University and Hospitals, Taichung 40402, Taiwan.
| | - Mohd Rais Mustafa
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
| |
Collapse
|
170
|
You H, Gao T, Cooper TK, Morris SM, Awad AS. Arginase inhibition: a new treatment for preventing progression of established diabetic nephropathy. Am J Physiol Renal Physiol 2015; 309:F447-55. [PMID: 26041444 DOI: 10.1152/ajprenal.00137.2015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/29/2015] [Indexed: 12/21/2022] Open
Abstract
Our previous publication showed that inhibition of arginase prevents the development of diabetic nephropathy (DN). However, identification of targets that retard the progression of established DN-which is more clinically relevant-is lacking. Therefore, we tested the hypothesis that arginase inhibition would prevent the progression of established DN. Effects of arginase inhibition were compared with treatment with the angiotensin-converting enzyme inhibitor captopril, a current standard of care in DN. Experiments were conducted in Ins2(Akita) mice treated with the arginase inhibitor S-(2-boronoethyl)-l-cysteine (BEC) or captopril starting at 6 wk of age for 12 wk (early treatment) or starting at 12 wk of age for 6 wk (late treatment). Early and late treatment with BEC resulted in protection from DN as indicated by reduced albuminuria, histological changes, kidney macrophage infiltration, urinary thiobarbituric acid-reactive substances, and restored nephrin expression, kidney nitrate/nitrite, kidney endothelial nitric oxide synthase phosphorylation, and renal medullary blood flow compared with vehicle-treated Ins2(Akita) mice at 18 wk of age. Interestingly, early treatment with captopril reduced albuminuria, histological changes, and kidney macrophage infiltration without affecting the other parameters, but late treatment with captopril was ineffective. These findings highlight the importance of arginase inhibition as a new potential therapeutic intervention in both early and late stages of diabetic renal injury.
Collapse
Affiliation(s)
- Hanning You
- Department of Medicine, Division of Nephrology, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Ting Gao
- Department of Medicine, Division of Nephrology, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Timothy K Cooper
- Department of Comparative Medicine, Penn State University College of Medicine, Hershey, Pennsylvania; and
| | - Sidney M Morris
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Alaa S Awad
- Department of Medicine, Division of Nephrology, Penn State University College of Medicine, Hershey, Pennsylvania;
| |
Collapse
|
171
|
Preclinical and clinical evidence for the role of resveratrol in the treatment of cardiovascular diseases. Biochim Biophys Acta Mol Basis Dis 2015; 1852:1155-77. [DOI: 10.1016/j.bbadis.2014.10.016] [Citation(s) in RCA: 211] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 10/24/2014] [Accepted: 10/27/2014] [Indexed: 12/12/2022]
|
172
|
Zheng C, Liu Z. Vascular function, insulin action, and exercise: an intricate interplay. Trends Endocrinol Metab 2015; 26:297-304. [PMID: 25735473 PMCID: PMC4450131 DOI: 10.1016/j.tem.2015.02.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 01/29/2015] [Accepted: 02/03/2015] [Indexed: 01/04/2023]
Abstract
Insulin enhances the compliance of conduit arteries, relaxes resistance arterioles to increase tissue blood flow, and dilates precapillary arterioles to expand muscle microvascular blood volume. These actions are impaired in the insulin resistant states. Exercise ameliorates endothelial dysfunction and improves insulin responses in insulin resistant patients, but the precise underlying mechanisms remain unclear. The microvasculature critically regulates insulin action in muscle by modulating insulin delivery to the capillaries nurturing the myocytes and trans-endothelial insulin transport. Recent data suggest that exercise may exert its insulin-sensitizing effect via recruiting muscle microvasculature to increase insulin delivery to and action in muscle. The current review focuses on how the interplay among exercise, insulin action, and the vasculature contributes to exercise-mediated insulin sensitization in muscle.
Collapse
Affiliation(s)
- Chao Zheng
- Diabetes Center and Department of Endocrinology, the Second Affiliated Hospital of Wenzhou Medical University, Zhejiang, China
| | - Zhenqi Liu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, USA.
| |
Collapse
|
173
|
Mutchler SM, Straub AC. Compartmentalized nitric oxide signaling in the resistance vasculature. Nitric Oxide 2015; 49:8-15. [PMID: 26028569 DOI: 10.1016/j.niox.2015.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 05/15/2015] [Accepted: 05/20/2015] [Indexed: 01/23/2023]
Abstract
Nitric oxide (NO) was first described as a bioactive molecule through its ability to stimulate soluble guanylate cyclase, but the revelation that NO was the endothelium derived relaxation factor drove the field to its modern state. The wealth of research conducted over the past 30 years has provided us with a picture of how diverse NO signaling can be within the vascular wall, going beyond simple vasodilation to include such roles as signaling through protein S-nitrosation. This expanded view of NO's actions requires highly regulated and compartmentalized production. Importantly, resistance arteries house multiple proteins involved in the production and transduction of NO allowing for efficient movement of the molecule to regulate vascular tone and reactivity. In this review, we focus on the many mechanisms regulating NO production and signaling action in the vascular wall, with a focus on the control of endothelial nitric oxide synthase (eNOS), the enzyme responsible for synthesizing most of the NO within these confines. We also explore how cross talk between the endothelium and smooth muscle in the microcirculation can modulate NO signaling, illustrating that this one small molecule has the capability to produce a plethora of responses.
Collapse
Affiliation(s)
- Stephanie M Mutchler
- Heart, Lung, Blood and Vascular Medicine Institute, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15216, USA
| | - Adam C Straub
- Heart, Lung, Blood and Vascular Medicine Institute, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15216, USA.
| |
Collapse
|
174
|
Al-Rasheed NM, Al-Rasheed NM, Attia HA, Al-Amin MA, Al-Ajmi HN, Hasan IH, Mohamad RA, Sinjilawi NA. Renoprotective Effects of Fenofibrate via Modulation of LKB1/AMPK mRNA Expression and Endothelial Dysfunction in a Rat Model of Diabetic Nephropathy. Pharmacology 2015; 95:229-39. [PMID: 25967095 DOI: 10.1159/000381190] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/21/2015] [Indexed: 11/19/2022]
Abstract
This study was conducted to investigate whether the renoprotective effects of fenofibrate are mediated via attenuation of endothelial dysfunction and modulating the mRNA expression of adenosine monophosphate-activated protein kinase (AMPK) and its downstream kinase liver kinase B1 (LKB1) in rats with diabetic nephropathy (DN). Diabetes was induced by a single intraperitoneal injection of streptozotocin (55 mg kg(-1)). Fenofibrate (100 mg kg(-1), p.o.) was given to diabetic rats daily for 12 weeks. Treatment with fenofibrate significantly improved the renal function as revealed by the significant reductions in urinary albumin excretion and serum levels of creatinine and urea, in addition to the significant increase in creatinine clearance compared with the diabetic control group. Hyperglycemia-induced oxidative damage was ameliorated by treatment with fenofibrate as indicated by the significantly increased levels of glutathione and catalase together with the significant decrease in lipid peroxidation. Administration of fenofibrate caused significant increases in renal nitric oxide (NO) production and mRNA expression of endothelial NO synthase (eNOS), AMPK and LKB1, reflecting improvement of endothelial function. Our results give further insights into the mechanisms underlying the protective role of fenofibrate in DN via modulation of AMPK, LKB1 and eNOS mRNA expression.
Collapse
Affiliation(s)
- Nawal M Al-Rasheed
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | | | | | | | | | | | | | | |
Collapse
|
175
|
Fu L, Li F, Bruckbauer A, Cao Q, Cui X, Wu R, Shi H, Xue B, Zemel MB. Interaction between leucine and phosphodiesterase 5 inhibition in modulating insulin sensitivity and lipid metabolism. Diabetes Metab Syndr Obes 2015; 8:227-39. [PMID: 25999751 PMCID: PMC4427070 DOI: 10.2147/dmso.s82338] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
PURPOSE Leucine activates SIRT1/AMP-activated protein kinase (AMPK) signaling and markedly potentiates the effects of other sirtuin and AMPK activators on insulin signaling and lipid metabolism. Phosphodiesterase 5 inhibition increases nitric oxide-cGMP signaling, which in turn exhibits a positive feedback loop with both SIRT1 and AMPK, thus amplifying peroxisome proliferator-activated receptor γ co-activator α (PGC1α)-mediated effects. METHODS We evaluated potential synergy between leucine and PDE5i on insulin sensitivity and lipid metabolism in vitro and in diet-induced obese (DIO) mice. RESULTS Leucine (0.5 mM) exhibited significant synergy with subtherapeutic doses (0.1-10 nM) of PDE5-inhibitors (sildenafil and icariin) on fat oxidation, nitric oxide production, and mitochondrial biogenesis in hepatocytes, adipocytes, and myotubes. Effects on insulin sensitivity, glycemic control, and lipid metabolism were then assessed in DIO-mice. DIO-mice exhibited fasting and postprandial hyperglycemia, insulin resistance, and hepatic steatosis, which were not affected by the addition of leucine (24 g/kg diet). However, the combination of leucine and a subtherapeutic dose of icariin (25 mg/kg diet) for 6 weeks reduced fasting glucose (38%, P<0.002), insulin (37%, P<0.05), area under the glucose tolerance curve (20%, P<0.01), and fully restored glucose response to exogenous insulin challenge. The combination also inhibited hepatic lipogenesis, stimulated hepatic and muscle fatty acid oxidation, suppressed hepatic inflammation, and reversed high-fat diet-induced steatosis. CONCLUSION These robust improvements in insulin sensitivity, glycemic control, and lipid metabolism indicate therapeutic potential for leucine-PDE5 inhibitor combinations.
Collapse
Affiliation(s)
- Lizhi Fu
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | - Fenfen Li
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | | | - Qiang Cao
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | - Xin Cui
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | - Rui Wu
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | - Hang Shi
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | - Bingzhong Xue
- Department of Biology, Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA
| | | |
Collapse
|
176
|
Liu Y, Park JM, Oh SJ, Chang KH, Lee MY. Antiplatelet effect of a newly developed AMP-activated protein kinase activator YLF-466D. Eur J Pharmacol 2015; 760:81-7. [PMID: 25913239 DOI: 10.1016/j.ejphar.2015.03.084] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 03/21/2015] [Accepted: 03/27/2015] [Indexed: 12/30/2022]
Abstract
AMP-activated protein kinase (AMPK) acts as a major regulator of cellular energy homeostasis. In platelets, AMPK activation stimulates endothelial nitric oxide synthase (eNOS) and its downstream signaling, and thereby inhibits platelet aggregation. In this study, a newly developed AMPK activator 3-[[(3E)-3-[(4-chlorophenyl)phenylmethylene]-2,3-dihydro-2-oxo-1H-indol-1-yl]methyl]-benzoic acid (YLF-466D) was tested for its antiplatelet activity. Treatment of isolated platelets with YLF-466D resulted in AMPK activation in a concentration-dependent manner in a range of 50-150 μM. Under the same experimental condition, YLF-466D effectively inhibited aggregation induced by platelet agonists including thrombin, ADP and collagen. Such AMPK activation and aggregation inhibition were abolished by pretreatment with the AMPK inhibitors compound C (CC) and ara-A, indicating that antiaggregatory effect of YLF-466D is mediated by AMPK. YLF-466D induced an activation-dependent eNOS phosphorylation at Ser1177, an elevation of cyclic nucleotides cGMP and cAMP, and subsequent phosphorylation of vasodilator-stimulated phosphoprotein (VASP) at Ser239 and Ser157. All these events were prevented by CC and ara-A. In addition to isolated platelets, YLF-466D attenuated whole blood aggregation induced by collagen. Taken together, YLF-466D is capable of inhibiting platelet aggregation by activating AMPK and its downstream eNOS-cGMP-PKG signaling axis. This study reconfirms the antiplatelet activity of AMPK activators and suggests the potential application of YLF-466D to antiplatelet therapy, although the in vivo and clinical validation remains to be assessed.
Collapse
Affiliation(s)
- Yingqiu Liu
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do 410-820, Republic of Korea
| | - Jung-Min Park
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do 410-820, Republic of Korea
| | - Seok-Jeong Oh
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do 410-820, Republic of Korea
| | - Kyung-Hwa Chang
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do 410-820, Republic of Korea
| | - Moo-Yeol Lee
- College of Pharmacy, Dongguk University, Goyang, Gyeonggi-do 410-820, Republic of Korea.
| |
Collapse
|
177
|
Heiss EH, Dirsch VM. Regulation of eNOS enzyme activity by posttranslational modification. Curr Pharm Des 2015; 20:3503-13. [PMID: 24180389 DOI: 10.2174/13816128113196660745] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/21/2013] [Indexed: 02/07/2023]
Abstract
The regulation of endothelial NO synthase (eNOS) employs multiple different cellular control mechanisms impinging on level and activity of the enzyme. This review aims at summarizing the current knowledge on the posttranslational modifications of eNOS, including acylation, nitrosylation, phosphorylation, acetylation, glycosylation and glutathionylation. Sites, mediators and impact on enzyme localization and activity of the single modifications will be discussed. Moreover, interdependence, cooperativity and competition between the different posttranslational modifications will be elaborated with special emphasis on the susceptibility of eNOS to metabolic cues.
Collapse
Affiliation(s)
| | - Verena M Dirsch
- University of Vienna, Department of Pharmacognosy, Althanstrasse14, 1090 Vienna, Austria.
| |
Collapse
|
178
|
Kume S, Yamato M, Tamura Y, Jin G, Nakano M, Miyashige Y, Eguchi A, Ogata Y, Goda N, Iwai K, Yamano E, Watanabe Y, Soga T, Kataoka Y. Potential biomarkers of fatigue identified by plasma metabolome analysis in rats. PLoS One 2015; 10:e0120106. [PMID: 25793974 PMCID: PMC4368560 DOI: 10.1371/journal.pone.0120106] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 01/19/2015] [Indexed: 11/22/2022] Open
Abstract
In the present study, prior to the establishment of a method for the clinical diagnosis of chronic fatigue in humans, we validated the utility of plasma metabolomic analysis in a rat model of fatigue using capillary electrophoresis-mass spectrometry (CE-MS). In order to obtain a fatigued animal group, rats were placed in a cage filled with water to a height of 2.2 cm for 5 days. A food-restricted group, in which rats were limited to 10 g/d of food (around 50% of the control group), was also assessed. The food-restricted group exhibited weight reduction similar to that of the fatigued group. CE-MS measurements were performed to evaluate the profile of food intake-dependent metabolic changes, as well as the profile in fatigue loading, resulting in the identification of 48 metabolites in plasma. Multivariate analyses using hierarchical clustering and principal component analysis revealed that the plasma metabolome in the fatigued group showed clear differences from those in the control and food-restricted groups. In the fatigued group, we found distinctive changes in metabolites related to branched-chain amino acid metabolism, urea cycle, and proline metabolism. Specifically, the fatigued group exhibited significant increases in valine, leucine, isoleucine, and 2-oxoisopentanoate, and significant decreases in citrulline and hydroxyproline compared with the control and food-restricted groups. Plasma levels of total nitric oxide were increased in the fatigued group, indicating systemic oxidative stress. Further, plasma metabolites involved in the citrate cycle, such as cis-aconitate and isocitrate, were reduced in the fatigued group. The levels of ATP were significantly decreased in the liver and skeletal muscle, indicative of a deterioration in energy metabolism in these organs. Thus, this comprehensive metabolic analysis furthered our understanding of the pathophysiology of fatigue, and identified potential diagnostic biomarkers based on fatigue pathophysiology.
Collapse
Affiliation(s)
- Satoshi Kume
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Masanori Yamato
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Yasuhisa Tamura
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Guanghua Jin
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Masayuki Nakano
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
- Department of Physiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Yukiharu Miyashige
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Asami Eguchi
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Yoshiyuki Ogata
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan
| | - Nobuhito Goda
- Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Kazuhiro Iwai
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Emi Yamano
- Department of Physiology, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Yasuyoshi Watanabe
- Department of Physiology, Osaka City University Graduate School of Medicine, Osaka, Japan
- Pathophysiological and Health Science Team, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
| | - Yosky Kataoka
- Cellular Function Imaging Team, Division of Bio-function Dynamics Imaging, RIKEN Center for Life Science Technologies, Kobe, Hyogo, Japan
- Department of Physiology, Osaka City University Graduate School of Medicine, Osaka, Japan
- * E-mail:
| |
Collapse
|
179
|
Sheldon RD, Padilla J, Jenkins NT, Laughlin MH, Rector RS. Chronic NOS inhibition accelerates NAFLD progression in an obese rat model. Am J Physiol Gastrointest Liver Physiol 2015; 308:G540-9. [PMID: 25573175 PMCID: PMC4360049 DOI: 10.1152/ajpgi.00247.2014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 01/07/2015] [Indexed: 01/31/2023]
Abstract
The progression in nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis is a serious health concern, but the underlying mechanisms remain unclear. We hypothesized that chronic inhibition of nitric oxide (NO) synthase (NOS) via N(ω)-nitro-L-arginine methyl ester (L-NAME) would intensify liver injury in a rat model of obesity, insulin resistance, and NAFLD. Obese Otsuka Long-Evans Tokushima fatty (OLETF) and lean Long-Evans Tokushima Otsuka (LETO) rats received control or L-NAME (65-70 mg·kg(-1)·day(-1))-containing drinking water for 4 wk. L-NAME treatment significantly (P < 0.05) reduced serum NO metabolites and food intake in both groups. Remarkably, despite no increase in body weight, L-NAME treatment increased hepatic triacylglycerol content (+40%, P < 0.05) vs. control OLETF rats. This increase was associated with impaired (P < 0.05) hepatic mitochondrial state 3 respiration. Interestingly, the opposite effect was found in LETO rats, where L-NAME increased (P < 0.05) hepatic mitochondrial state 3 respiration. In addition, L-NAME induced a shift toward proinflammatory M1 macrophage polarity, as indicated by elevated hepatic CD11c (P < 0.05) and IL-1β (P = 0.07) mRNA in OLETF rats and reduced expression of the anti-inflammatory M2 markers CD163 and CD206 (P < 0.05) in LETO rats. Markers of total macrophage content (CD68 and F4/80) mRNA were unaffected by L-NAME in either group. In conclusion, systemic NOS inhibition in the obese OLETF rats reduced hepatic mitochondrial respiration, increased hepatic triacylglycerol accumulation, and increased hepatic inflammation. These findings suggest an important role for proper NO metabolism in the hepatic adaptation to obesity.
Collapse
Affiliation(s)
- Ryan D Sheldon
- Research Service, Harry S Truman Memorial Veterans Affairs Hospital, Columbia, Missouri; Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri
| | - Jaume Padilla
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; Department of Child Health, University of Missouri, Columbia, Missouri; Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri
| | - Nathan T Jenkins
- Department of Kinesiology, University of Georgia, Athens, Georgia
| | - M Harold Laughlin
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri; Department of Biomedical Sciences, University of Missouri, Columbia, Missouri; Department of Medical Physiology and Pharmacology, University of Missouri, Columbia, Missouri
| | - R Scott Rector
- Research Service, Harry S Truman Memorial Veterans Affairs Hospital, Columbia, Missouri; Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri; Department of Medicine-Gastroenterology and Hepatology, University of Missouri, Columbia, Missouri; and
| |
Collapse
|
180
|
Wang DT, He J, Wu M, Li SM, Gao Q, Zeng QP. Artemisinin mimics calorie restriction to trigger mitochondrial biogenesis and compromise telomere shortening in mice. PeerJ 2015; 3:e822. [PMID: 25780774 PMCID: PMC4358698 DOI: 10.7717/peerj.822] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/16/2015] [Indexed: 12/23/2022] Open
Abstract
Calorie restriction is known to extend lifespan among organisms by a debating mechanism underlying nitric oxide-driven mitochondrial biogenesis. We report here that nitric oxide generators including artemisinin, sodium nitroprusside, and L-arginine mimics calorie restriction and resembles hydrogen peroxide to initiate the nitric oxide signaling cascades and elicit the global antioxidative responses in mice. The large quantities of antioxidant enzymes are correlated with the low levels of reactive oxygen species, which allow the down-regulation of tumor suppressors and accessory DNA repair partners, eventually leading to the compromise of telomere shortening. Accompanying with the up-regulation of signal transducers and respiratory chain signatures, mitochondrial biogenesis occurs with the elevation of adenosine triphosphate levels upon exposure of mouse skeletal muscles to the mimetics of calorie restriction. In conclusion, calorie restriction-triggered nitric oxide provides antioxidative protection and alleviates telomere attrition via mitochondrial biogenesis, thereby maintaining chromosomal stability and integrity, which are the hallmarks of longevity.
Collapse
Affiliation(s)
- Da-Ting Wang
- Tropical Medicine Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jiang He
- Tropical Medicine Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ming Wu
- School of Life Science, Sun Yat-sen University, Guangzhou, China
| | - Si-Ming Li
- The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qian Gao
- Tropical Medicine Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Qing-Ping Zeng
- Tropical Medicine Institute, Guangzhou University of Chinese Medicine, Guangzhou, China
| |
Collapse
|
181
|
Maiwulanjiang M, Bi CWC, Lee PSC, Xin G, Miernisha A, Lau KM, Xiong A, Li N, Dong TTX, Aisa HA, Tsim KWK. The volatile oil of Nardostachyos Radix et Rhizoma induces endothelial nitric oxide synthase activity in HUVEC cells. PLoS One 2015; 10:e0116761. [PMID: 25643147 PMCID: PMC4359165 DOI: 10.1371/journal.pone.0116761] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 12/13/2014] [Indexed: 11/30/2022] Open
Abstract
Nardostahyos Radix et Rhizoma (NRR; the root and rhizome of Nardostachys jatamansi DC.) is a widely used medicinal herb. Historically, NRR is being used for the treatment of cardiovascular and neurological diseases. To search for active ingredients of NRR, we investigated the vascular benefit of NRR volatile oil in (i) the vasodilation in rat aorta ring, and (ii) the release of nitric oxide (NO) and the phosphorylation of endothelial NO synthase (eNOS) in cultured human umbilical vein endothelial cells (HUVECs). By measuring the fluorescence signal in cultures, application of NRR volatile oil resulted in a rapid activation of NO release as well as the phosphorylation of eNOS: both inductions were markedly reduced by L-NAME. In parallel, the phosphorylation level of Akt kinase was markedly increased by the oil treatment, which was partially attenuated by PI3K/Akt inhibitor LY294002. This inhibitor also blocked the NRR-induced NO production and eNOS phosphorylation. In HUVECs, application of NRR volatile oil elevated the intracellular Ca(2+) level, and BAPTA-AM, a Ca(2+) chelator, reduced the Ca(2+) surge: the blockage were also applied to NRR-induced eNOS phosphorylation and NO production. These findings suggested the volatile oil of NRR was the major ingredient in triggering the vascular dilatation, and which was mediated via the NO production.
Collapse
Affiliation(s)
- Maitinuer Maiwulanjiang
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Cathy W. C. Bi
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Pinky S. C. Lee
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Guizhong Xin
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Abudureyimu Miernisha
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Kei M. Lau
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Aizhen Xiong
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ning Li
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tina T. X. Dong
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Haji A. Aisa
- Xinjiang Key Laboratory of Plant Resources and Natural Products Chemistry, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, China
| | - Karl W. K. Tsim
- Division of Life Science and Centre for Chinese Medicine, The Hong Kong University of Science and Technology, Hong Kong, China
| |
Collapse
|
182
|
Metformin stimulates ischemia-induced revascularization through an eNOS dependent pathway in the ischemic hindlimb mice model. J Vasc Surg 2015; 61:489-96. [DOI: 10.1016/j.jvs.2013.09.061] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 08/08/2013] [Accepted: 09/17/2013] [Indexed: 11/24/2022]
|
183
|
Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway. Biochem Biophys Res Commun 2015; 456:541-6. [DOI: 10.1016/j.bbrc.2014.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 12/01/2014] [Indexed: 01/29/2023]
|
184
|
Metabolic effects of resveratrol: addressing the controversies. Cell Mol Life Sci 2014; 72:1473-88. [PMID: 25548801 DOI: 10.1007/s00018-014-1808-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 12/09/2014] [Accepted: 12/15/2014] [Indexed: 10/24/2022]
Abstract
Resveratrol, a polyphenol found in a number of plant-based foods such as red wine, has received a great deal of attention for its diverse array of healthful effects. Beneficial effects of resveratrol are diverse; they include improvement of mitochondrial function, protection against obesity and obesity-related diseases such as type-2 diabetes, suppression of inflammation and cancer cell growth and protection against cardiovascular dysfunction, just to name a few. Investigations into the metabolic effects of resveratrol are furthest along and now include a number of clinical trials, which have yielded mixed results. There are a number of controversies surrounding resveratrol that have not been resolved. Here, we will review these controversies with particular emphasis on its mechanism of metabolic action and how lessons from resveratrol may help develop therapies that harness the effects of resveratrol but without the undesirable properties of resveratrol.
Collapse
|
185
|
García-Prieto CF, Hernández-Nuño F, Rio DD, Ruiz-Hurtado G, Aránguez I, Ruiz-Gayo M, Somoza B, Fernández-Alfonso MS. High-fat diet induces endothelial dysfunction through a down-regulation of the endothelial AMPK-PI3K-Akt-eNOS pathway. Mol Nutr Food Res 2014; 59:520-32. [PMID: 25421217 DOI: 10.1002/mnfr.201400539] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 11/08/2014] [Accepted: 11/13/2014] [Indexed: 11/11/2022]
Abstract
SCOPE Activation of endothelial adenosine monophosphate-activated protein kinase (AMPK) contributes to increase nitric oxide (NO) availability. The aim of this study was to assess if high-fat diet (HFD)-induced endothelial dysfunction is linked to AMPK deregulation. METHODS AND RESULTS Twelve-week-old Sprague Dawley male rats were assigned either to control (10 kcal % from fat) or to HFD (45 kcal % from fat) for 8 wk. HFD rats segregated in obesity-prone (OP) or obesity-resistant (OR) rats according to body weight. HFD triggered an impaired glucose management together with impaired endothelium-dependent relaxation, reduced endothelial AMPK activity and lower NO availability in aortic rings of OP and OR cohorts. Relaxation evoked by AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) was reduced in both OP and OR rings, which exhibited lower p-AMPKα-Thr(172) /AMPKα ratios that negatively correlated with plasma non-esterified fatty acids (NEFA) and triglycerides (TG). Inhibition of PI3K (wortmannin, 10(-7) M) or Akt (triciribine, 10(-5) M) reduced relaxation to AICAR only in the control group (p < 0.001). Akt (p-Akt-Ser(473) ) and eNOS phosphorylation (p-eNOS-Ser(1177) ) were significantly reduced in OP and OR (p < 0.01). CONCLUSION Endothelial dysfunction caused by HFD is related to a dysfunctional endothelial AMPK-PI3K-Akt-eNOS pathway correlating with the increase of plasma NEFA, TG, and an impaired glucose management.
Collapse
Affiliation(s)
- Concha F García-Prieto
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, Madrid, Spain
| | | | | | | | | | | | | | | |
Collapse
|
186
|
Seo J, Lee JY, Sung MS, Byun CJ, Cho DH, Lee HJ, Park JH, Cho HS, Cho SJ, Jo I. Arsenite Acutely Decreases Nitric Oxide Production via the ROS-Protein Phosphatase 1-Endothelial Nitric Oxide Synthase-Thr(497) Signaling Cascade. Biomol Ther (Seoul) 2014; 22:510-8. [PMID: 25489418 PMCID: PMC4256030 DOI: 10.4062/biomolther.2014.106] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 10/16/2014] [Accepted: 10/22/2014] [Indexed: 11/17/2022] Open
Abstract
Chronic (>24 h) exposure of arsenite, an environmental toxicant, has shown the decreased nitric oxide (NO) production in endothelial cells (EC) by decreasing endothelial NO synthase (eNOS) expression and/or its phosphorylation at serine 1179 (eNOS-Ser1179 in bovine sequence), which is associated with increased risk of vascular diseases. Here, we investigated the acute (<24 h) effect of arsenite on NO production using bovine aortic EC (BAEC). Arsenite acutely increased the phosphorylation of eNOS-Thr497, but not of eNOS-Ser116 or eNOS-Ser1179, which was accompanied by decreased NO production. The level of eNOS expression was unaltered under this condition. Treatment with arsenite also induced reactive oxygen species (ROS) production, and pretreatment with a ROS scavenger N-acetyl-L-cysteine (NAC) completely reversed the observed effect of arsenite on eNOS-Thr497 phosphorylation. Although protein kinase C (PKC) and protein phosphatase 1 (PP1) were reported to be involved in eNOS-Thr497 phosphorylation, treatment with PKC inhibitor, Ro318425, and overexpression of various PKC isoforms did not affect the arsenite-stimulated eNOS-Thr497 phosphorylation. In contrast, treatment with PP1 inhibitor, calyculin A, mimicked the observed effect of arsenite on eNOS-Thr497 phosphorylation. Lastly, we found decreased cellular PP1 activity in arsenite-treated cells, which was reversed by NAC. Overall, our study demonstrates firstly that arsenite acutely decreases NO production at least in part by increasing eNOS-Thr497 phosphorylation via ROS-PP1 signaling pathway, which provide the molecular mechanism underlying arsenite-induced increase in vascular disease.
Collapse
Affiliation(s)
- Jungwon Seo
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710 ; Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749
| | - Jee Young Lee
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710
| | - Min-Sun Sung
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710
| | | | - Du-Hyong Cho
- Department of Pharmacology, School of Medicine, Eulji University, Daejeon 301-768
| | - Hyeon-Ju Lee
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710
| | - Jung-Hyun Park
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710
| | - Ho-Seong Cho
- Biosafety Research Institute and College of Veterinary Medicine, Chonbuk National University, Jeonju 561-756
| | - Sung-Jin Cho
- Department of Biology, College of Natural Sciences, Chungbuk National University, Cheongju 362-763, Republic of Korea
| | - Inho Jo
- Department of Molecular Medicine, School of Medicine, Ewha Womans University, Seoul 158-710
| |
Collapse
|
187
|
Tetramethylpyrazine Analogue CXC195 Ameliorates Cerebral Ischemia–reperfusion Injury by Regulating Endothelial Nitric Oxide Synthase Phosphorylation Via PI3K/Akt Signaling. Neurochem Res 2014; 40:446-54. [DOI: 10.1007/s11064-014-1485-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/03/2014] [Accepted: 11/19/2014] [Indexed: 12/26/2022]
|
188
|
Xu L, Wang S, Li B, Sun A, Zou Y, Ge J. A protective role of ciglitazone in ox-LDL-induced rat microvascular endothelial cells via modulating PPARγ-dependent AMPK/eNOS pathway. J Cell Mol Med 2014; 19:92-102. [PMID: 25388834 PMCID: PMC4288353 DOI: 10.1111/jcmm.12463] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 09/19/2014] [Indexed: 01/10/2023] Open
Abstract
Thiazolidinediones, the antidiabetic agents such as ciglitazone, has been proved to be effective in limiting atherosclerotic events. However, the underlying mechanism remains elucidative. Ox-LDL receptor-1 (LOX-1) plays a central role in ox-LDL-mediated atherosclerosis via endothelial nitric oxide synthase (eNOS) uncoupling and nitric oxide reduction. Therefore, we tested the hypothesis that ciglitazone, the PPARγ agonist, protected endothelial cells against ox-LDL through regulating eNOS activity and LOX-1 signalling. In the present study, rat microvascular endothelial cells (RMVECs) were stimulated by ox-LDL. The impact of ciglitazone on cell apoptosis and angiogenesis, eNOS expression and phosphorylation, nitric oxide synthesis and related AMPK, Akt and VEGF signalling pathway were observed. Our data showed that both eNOS and Akt phosphorylation, VEGF expression and nitric oxide production were significantly decreased, RMVECs ageing and apoptosis increased after ox-LDL induction for 24 hrs, all of which were effectively reversed by ciglitazone pre-treatment. Meanwhile, phosphorylation of AMP-activated protein kinase (AMPK) was suppressed by ox-LDL, which was also prevented by ciglitazone. Of interest, AMPK inhibition abolished ciglitazone-mediated eNOS function, nitric oxide synthesis and angiogenesis, and increased RMVECs ageing and apoptosis. Further experiments showed that inhibition of PPARγ significantly suppressed AMPK phosphorylation, eNOS expression and nitric oxide production. Ciglitazone-mediated angiogenesis and reduced cell ageing and apoptosis were reversed. Furthermore, LOX-1 protein expression in RMVECs was suppressed by ciglitazone, but re-enhanced by blocking PPARγ or AMPK. Ox-LDL-induced suppression of eNOS and nitric oxide synthesis were largely prevented by silencing LOX-1. Collectively, these data demonstrate that ciglitazone-mediated PPARγ activation suppresses LOX-1 and moderates AMPK/eNOS pathway, which contributes to endothelial cell survival and function preservation.
Collapse
Affiliation(s)
- Lei Xu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Institutes of Biomedical Science, Fudan University, Shanghai, China
| | | | | | | | | | | |
Collapse
|
189
|
Molecular modeling and simulation of the human eNOS reductase domain, an enzyme involved in the release of vascular nitric oxide. J Mol Model 2014; 20:2470. [DOI: 10.1007/s00894-014-2470-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 09/14/2014] [Indexed: 01/19/2023]
|
190
|
Dolinsky VW, Dyck JRB. Experimental studies of the molecular pathways regulated by exercise and resveratrol in heart, skeletal muscle and the vasculature. Molecules 2014; 19:14919-47. [PMID: 25237749 PMCID: PMC6271699 DOI: 10.3390/molecules190914919] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 09/10/2014] [Accepted: 09/10/2014] [Indexed: 01/07/2023] Open
Abstract
Regular exercise contributes to healthy aging and the prevention of chronic disease. Recent research has focused on the development of molecules, such as resveratrol, that activate similar metabolic and stress response pathways as exercise training. In this review, we describe the effects of exercise training and resveratrol on some of the organs and tissues that act in concert to transport oxygen throughout the body. In particular, we focus on animal studies that investigate the molecular signaling pathways induced by these interventions. We also compare and contrast the effects of exercise and resveratrol in diseased states.
Collapse
Affiliation(s)
- Vernon W Dolinsky
- Department of Pharmacology & Therapeutics and the Diabetes Research Envisioned and Accomplished in Manitoba (DREAM) Research Theme of the Manitoba Institute of Child Health, University of Manitoba, 601 John Buhler Research Centre, 715 McDermot Avenue, Winnipeg, MB R3E 3P4, Canada.
| | - Jason R B Dyck
- Department of Pediatrics and the Cardiovascular Research Centre, Mazankowski Alberta Heart Institute, University of Alberta, 458 Heritage Medical Research Centre, Edmonton, AB T6G 2S2, Canada.
| |
Collapse
|
191
|
Kolluru GK, Majumder S, Chatterjee S. Rho-kinase as a therapeutic target in vascular diseases: striking nitric oxide signaling. Nitric Oxide 2014; 43:45-54. [PMID: 25196952 DOI: 10.1016/j.niox.2014.09.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 11/27/2022]
Abstract
Rho GTPases are a globular, monomeric group of small signaling G-protein molecules. Rho-associated protein kinase/Rho-kinase (ROCK) is a downstream effector protein of the Rho GTPase. Rho-kinases are the potential therapeutic targets in the treatment of cardiovascular diseases. Here, we have primarily discussed the intriguing roles of ROCK in cardiovascular health in relation to nitric oxide signaling. Further, we highlighted the biphasic effects of Y-27632, a ROCK inhibitor under shear stress, which acts as an agonist of nitric oxide production in endothelial cells. The biphasic effects of this inhibitor raised the question of safety of the drug usage in treating cardiovascular diseases.
Collapse
Affiliation(s)
| | - Syamantak Majumder
- Aab Cardiovascular Research Institute, School of Medicine and Dentistry, University of Rochester, Rochester, NY, USA
| | - Suvro Chatterjee
- Department of Biotechnology, Anna University, Chennai, India; Vascular Biology Lab, AU-KBC Research Centre, Anna University, Chennai, India.
| |
Collapse
|
192
|
Rana S, Blowers EC, Natarajan A. Small molecule adenosine 5'-monophosphate activated protein kinase (AMPK) modulators and human diseases. J Med Chem 2014; 58:2-29. [PMID: 25122135 DOI: 10.1021/jm401994c] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Adenosine 5'-monophosphate activated protein kinase (AMPK) is a master sensor of cellular energy status that plays a key role in the regulation of whole-body energy homeostasis. AMPK is a serine/threonine kinase that is activated by upstream kinases LKB1, CaMKKβ, and Tak1, among others. AMPK exists as αβγ trimeric complexes that are allosterically regulated by AMP, ADP, and ATP. Dysregulation of AMPK has been implicated in a number of metabolic diseases including type 2 diabetes mellitus and obesity. Recent studies have associated roles of AMPK with the development of cancer and neurological disorders, making it a potential therapeutic target to treat human diseases. This review focuses on the structure and function of AMPK, its role in human diseases, and its direct substrates and provides a brief synopsis of key AMPK modulators and their relevance in human diseases.
Collapse
Affiliation(s)
- Sandeep Rana
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center , Omaha, Nebraska 68198-6805, United States
| | | | | |
Collapse
|
193
|
Mechanistic perspectives of calorie restriction on vascular homeostasis. SCIENCE CHINA-LIFE SCIENCES 2014; 57:742-54. [DOI: 10.1007/s11427-014-4709-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 07/04/2014] [Indexed: 02/06/2023]
|
194
|
Chen F, Kumar S, Yu Y, Aggarwal S, Gross C, Wang Y, Chakraborty T, Verin AD, Catravas JD, Lucas R, Black SM, Fulton DJR. PKC-dependent phosphorylation of eNOS at T495 regulates eNOS coupling and endothelial barrier function in response to G+ -toxins. PLoS One 2014; 9:e99823. [PMID: 25020117 PMCID: PMC4096401 DOI: 10.1371/journal.pone.0099823] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 05/19/2014] [Indexed: 11/30/2022] Open
Abstract
Gram positive (G+) infections make up ∼50% of all acute lung injury cases which are characterized by extensive permeability edema secondary to disruption of endothelial cell (EC) barrier integrity. A primary cause of increased permeability are cholesterol-dependent cytolysins (CDCs) of G+-bacteria, such as pneumolysin (PLY) and listeriolysin-O (LLO) which create plasma membrane pores, promoting Ca2+-influx and activation of PKCα. In human lung microvascular endothelial cells (HLMVEC), pretreatment with the nitric oxide synthase (NOS) inhibitor, ETU reduced the ability of LLO to increase microvascular cell permeability suggesting an endothelial nitric oxide synthase (eNOS)-dependent mechanism. LLO stimulated superoxide production from HLMVEC and this was prevented by silencing PKCα or NOS inhibition suggesting a link between these pathways. Both LLO and PLY stimulated eNOS T495 phosphorylation in a PKC-dependent manner. Expression of a phosphomimetic T495D eNOS (human isoform) resulted in increased superoxide and diminished nitric oxide (NO) production. Transduction of HLMVEC with an active form of PKCα resulted in the robust phosphorylation of T495 and increased peroxynitrite production, indicative of eNOS uncoupling. To determine the mechanisms underlying eNOS uncoupling, HLMVEC were stimulated with LLO and the amount of hsp90 and caveolin-1 bound to eNOS determined. LLO stimulated the dissociation of hsp90, and in particular, caveolin-1 from eNOS. Both hsp90 and caveolin-1 have been shown to influence eNOS uncoupling and a peptide mimicking the scaffolding domain of caveolin-1 blocked the ability of PKCα to stimulate eNOS-derived superoxide. Collectively, these results suggest that the G+ pore-forming toxins promote increased EC permeability via activation of PKCα, phosphorylation of eNOS-T495, loss of hsp90 and caveolin-1 binding which collectively promote eNOS uncoupling and the production of barrier disruptive superoxide.
Collapse
Affiliation(s)
- Feng Chen
- Department of Forensic Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Sanjiv Kumar
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Yanfang Yu
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Saurabh Aggarwal
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Christine Gross
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Yusi Wang
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Trinad Chakraborty
- Institute for Medical Microbiology, Justus Liebig University, Giessen, Germany
| | - Alexander D. Verin
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - John D. Catravas
- Old Dominion University, Norfolk, Virginia, United States of America
| | - Rudolf Lucas
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
- Department of Pharmacology, Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - Stephen M. Black
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
| | - David J. R. Fulton
- Vascular Biology Center Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
- Department of Pharmacology, Medical College of Georgia at Georgia Regents University, Augusta, Georgia, United States of America
- * E-mail:
| |
Collapse
|
195
|
Hyndman KA, Ho DH, Sega MF, Pollock JS. Histone deacetylase 1 reduces NO production in endothelial cells via lysine deacetylation of NO synthase 3. Am J Physiol Heart Circ Physiol 2014; 307:H803-9. [PMID: 25015965 DOI: 10.1152/ajpheart.00243.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The lysine acetylation state of nonhistone proteins may be regulated through histone deacetylases (HDACs). Evidence suggests that nitric oxide (NO) synthase 3 (NOS3; endothelial NOS) is posttranslationally lysine acetylated, leading to increased NO production in the endothelium. We tested the hypothesis that NOS3 is lysine acetylated and that upregulated HDAC1-mediated deacetylation leads to reduced NO production in endothelial cells. We determined that NOS3 is basally lysine acetylated in cultured bovine aortic endothelial cells (BAECs). In BAECs, HDAC1 is expressed in the nucleus and cytosol and forms a novel protein-protein interaction with NOS3. Overexpression of HDAC1 in BAECs resulted in a significant reduction in NOS3 lysine acetylation (control = 1.0 ± 0.1 and HDAC1 = 0.59 ± 0.08 arbitrary units, P < 0.01) and significantly blunted basal nitrite production (control 287.7 ± 29.1 and HDAC1 172.4 ± 31.7 pmol·mg(-1)·h(-1), P < 0.05) as well as attenuating endothelin-1-stimulated nitrite production (control = 481.8 ± 50.3 and HDAC1 243.1 ± 48.2 pmol·mg(-1)·h(-1), P < 0.05). While HDAC1 knockdown with small-interfering RNA resulted in no change in NOS3 acetylation level, yet increased basal nitrite production (730.6 ± 99.1 pmol·mg(-1)·h(-1)) and further exaggerated increases in endothelin-1 stimulated nitrite production (1276.9 ± 288.2 pmol·mg(-1)·h(-1)) was observed. Moreover, overexpression or knockdown of HDAC1 resulted in no significant effect on NOS3 protein expression or NOS3 phosphorylation sites T497, S635, or S1179. Thus these data indicate that upregulated HDAC1 decreases NOS3 activity, most likely through direct lysine deacetylation of NOS3. We propose that HDAC1-mediated deacetylation of NOS3 may represent a novel target for endothelial dysfunction.
Collapse
Affiliation(s)
- Kelly A Hyndman
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Dao H Ho
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Martiana F Sega
- Department of Medicine, Georgia Regents University, Augusta, Georgia
| | - Jennifer S Pollock
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Medicine, Georgia Regents University, Augusta, Georgia
| |
Collapse
|
196
|
Ramadoss J, Pastore MB, Magness RR. Endothelial caveolar subcellular domain regulation of endothelial nitric oxide synthase. Clin Exp Pharmacol Physiol 2014; 40:753-64. [PMID: 23745825 DOI: 10.1111/1440-1681.12136] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 05/29/2013] [Accepted: 05/31/2013] [Indexed: 12/12/2022]
Abstract
Complex regulatory processes alter the activity of endothelial nitric oxide synthase (eNOS) leading to nitric oxide (NO) production by endothelial cells under various physiological states. These complex processes require specific subcellular eNOS partitioning between plasma membrane caveolar domains and non-caveolar compartments. Translocation of eNOS from the plasma membrane to intracellular compartments is important for eNOS activation and subsequent NO biosynthesis. We present data reviewing and interpreting information regarding: (i) the coupling of endothelial plasma membrane receptor systems in the caveolar structure relative to eNOS trafficking; (ii) how eNOS trafficking relates to specific protein-protein interactions for inactivation and activation of eNOS; and (iii) how these complex mechanisms confer specific subcellular location relative to eNOS multisite phosphorylation and signalling. Dysfunction in the regulation of eNOS activation may contribute to several disease states, in particular gestational endothelial abnormalities (pre-eclampsia, gestational diabetes etc.), that have life-long deleterious health consequences that predispose the offspring to develop hypertensive disease, Type 2 diabetes and adiposity.
Collapse
Affiliation(s)
- Jayanth Ramadoss
- Department of Obstetrics and Gynaecology, University of Texas Medical Branch, Galveston, TX, USA
| | | | | |
Collapse
|
197
|
AMP kinase regulates K-ATP currents evoked by NMDA receptor stimulation in rat subthalamic nucleus neurons. Neuroscience 2014; 274:138-52. [PMID: 24875176 DOI: 10.1016/j.neuroscience.2014.05.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 05/10/2014] [Accepted: 05/18/2014] [Indexed: 11/21/2022]
Abstract
Our lab recently showed that N-methyl-D-aspartate (NMDA) evokes ATP-sensitive K(+) (K-ATP) currents in subthalamic nucleus (STN) neurons in slices of the rat brain. Both K-ATP channels and 5'-adenosine monophosphate-activated protein kinase (AMPK) are considered cellular energy sensors because their activities are influenced by the phosphorylation state of adenosine nucleotides. Moreover, AMPK has been shown to regulate K-ATP function in a variety of tissues including pancreas, cardiac myocytes, and hypothalamus. We used whole-cell patch clamp recordings to study the effect of AMPK activation on K-ATP channel function in STN neurons in slices of the rat brain. We found that bath or intracellular application of the AMPK activators A769662 and PT1 augmented tolbutamide-sensitive K-ATP currents evoked by NMDA receptor stimulation. The effect of AMPK activators was blocked by the AMPK inhibitor dorsomorphin (compound C), and by STO609, an inhibitor of the upstream AMPK activator CaMKKβ. AMPK augmentation of NMDA-induced K-ATP current was also blocked by intracellular BAPTA and by inhibitors of nitric oxide synthase and guanylyl cyclase. However, A769662 did not augment currents evoked by the K-ATP channel opener diazoxide. In the presence of NMDA, A769662 inhibited depolarizing plateau potentials and burst firing, both of which could be antagonized by tolbutamide or dorsomorphin. These studies show that AMPK augments NMDA-induced K-ATP currents by a Ca(2+)-dependent process that involves nitric oxide and cGMP. By augmenting K-ATP currents, AMPK activation would be expected to dampen the excitatory effect of glutamate-mediated transmission in the STN.
Collapse
|
198
|
Enkhjargal B, Godo S, Sawada A, Suvd N, Saito H, Noda K, Satoh K, Shimokawa H. Endothelial AMP-activated protein kinase regulates blood pressure and coronary flow responses through hyperpolarization mechanism in mice. Arterioscler Thromb Vasc Biol 2014; 34:1505-13. [PMID: 24855056 DOI: 10.1161/atvbaha.114.303735] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Vascular endothelium plays an important role to maintain cardiovascular homeostasis through several mechanisms, including endothelium-dependent hyperpolarization (EDH). We have recently demonstrated that EDH is involved in endothelial metabolic regulation in mice. However, it remains to be examined whether AMP-activated protein kinase (AMPK), an important metabolic regulator, is involved in EDH and if so, whether endothelial AMPK (eAMPK) plays a role for circulatory regulation. APPROACH AND RESULTS We examined the role of eAMPK in EDH, using mice with endothelium-specific deficiency of α-catalytic subunit of AMPK, either α1 (eAMPKα1 (-/-)α2 (+/+)) or α2 (eAMPKα1 (+/+)α2 (-/-)) alone or both of them (eAMPKα1 (-/-)α2 (-/-)). We performed telemetry, organ chamber, electrophysiological, and Langendorff experiments to examine blood pressure, vascular responses, hyperpolarization of membrane potential, and coronary flow responses, respectively. Hypertension was noted throughout the day in eAMPKα1 (-/-)α2 (-/-) and eAMPKα1 (-/-)α2 (+/+) but not in eAMPKα1 (+/+)α2 (-/-) mice when compared with respective control. Importantly, endothelium-dependent relaxations, EDH, and coronary flow increase were all significantly reduced in eAMPKα1 (-/-)α2 (-/-) and eAMPKα1 (-/-)α2 (+/+) but not in eAMPKα1 (+/+)α2 (-/-) mice. In contrast, endothelium-independent relaxations to sodium nitroprusside (a NO donor), NS-1619 (a Ca(2+)-activated K(+) channel opener), and exogenous H2O2 were almost comparable among the groups. In eAMPKα1 (-/-)α2 (-/-) mice, antihypertensive treatment with hydralazine or long-term treatment with metformin (a stimulator of AMPK) failed to restore EDH-mediated responses. CONCLUSIONS These results provide the first direct evidence that α1 subunit of eAMPK substantially mediates EDH responses of microvessels and regulates blood pressure and coronary flow responses in mice in vivo, demonstrating the novel role of eAMPK in cardiovascular homeostasis.
Collapse
Affiliation(s)
- Budbazar Enkhjargal
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Shigeo Godo
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Ayuko Sawada
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Nergui Suvd
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Hiroki Saito
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Kazuki Noda
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Kimio Satoh
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan
| | - Hiroaki Shimokawa
- From the Department of Cardiovascular Medicine, Tohoku University, Sendai, Japan.
| |
Collapse
|
199
|
Vinegar Intake Enhances Flow-Mediated VasodilatationviaUpregulation of Endothelial Nitric Oxide Synthase Activity. Biosci Biotechnol Biochem 2014; 74:1055-61. [DOI: 10.1271/bbb.90953] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
|
200
|
Zhu M, Chen J, Yin H, Jiang H, Wen M, Miao C. Propofol protects human umbilical vein endothelial cells from cisplatin-induced injury. Vascul Pharmacol 2014; 61:72-9. [DOI: 10.1016/j.vph.2014.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 03/24/2014] [Accepted: 04/02/2014] [Indexed: 02/07/2023]
|