1
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Fonódi M, Nagy L, Boratkó A. Role of Protein Phosphatases in Tumor Angiogenesis: Assessing PP1, PP2A, PP2B and PTPs Activity. Int J Mol Sci 2024; 25:6868. [PMID: 38999976 PMCID: PMC11241275 DOI: 10.3390/ijms25136868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/14/2024] Open
Abstract
Tumor angiogenesis, the formation of new blood vessels to support tumor growth and metastasis, is a complex process regulated by a multitude of signaling pathways. Dysregulation of signaling pathways involving protein kinases has been extensively studied, but the role of protein phosphatases in angiogenesis within the tumor microenvironment remains less explored. However, among angiogenic pathways, protein phosphatases play critical roles in modulating signaling cascades. This review provides a comprehensive overview of the involvement of protein phosphatases in tumor angiogenesis, highlighting their diverse functions and mechanisms of action. Protein phosphatases are key regulators of cellular signaling pathways by catalyzing the dephosphorylation of proteins, thereby modulating their activity and function. This review aims to assess the activity of the protein tyrosine phosphatases and serine/threonine phosphatases. These phosphatases exert their effects on angiogenic signaling pathways through various mechanisms, including direct dephosphorylation of angiogenic receptors and downstream signaling molecules. Moreover, protein phosphatases also crosstalk with other signaling pathways involved in angiogenesis, further emphasizing their significance in regulating tumor vascularization, including endothelial cell survival, sprouting, and vessel maturation. In conclusion, this review underscores the pivotal role of protein phosphatases in tumor angiogenesis and accentuate their potential as therapeutic targets for anti-angiogenic therapy in cancer.
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Affiliation(s)
| | | | - Anita Boratkó
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary; (M.F.); (L.N.)
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2
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Ghezzi AC, Passos GR, de Oliveira MG, Oliveira AL, Assis-Mendonça GR, de Mello GC, Antunes E, Monica FZ. A 2-week treatment with 5-azacytidine improved the hypercontractility state in prostate from obese mice: Role of the nitric oxide-cyclic guanosine monophosphate signalling pathway. Clin Exp Pharmacol Physiol 2024; 51:e13851. [PMID: 38452757 DOI: 10.1111/1440-1681.13851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 01/11/2024] [Accepted: 02/12/2024] [Indexed: 03/09/2024]
Abstract
Benign prostatic hyperplasia (BPH) is characterised by increases in prostate volume and contraction. Downregulation of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signalling pathway contributes to prostate dysfunctions. Previous studies in cancer cells or vessels have shown that the epigenetic mechanisms control the gene and protein expression of the enzymes involved in the production of NO and cGMP. This study is aimed to evaluate the effect of a 2-week treatment of 5-azacytidine (5-AZA), a DNA-methyltransferase inhibitor, in the prostate function of mice fed with a high-fat diet. Functional, histological, biochemical and molecular assays were carried out. Obese mice presented greater prostate weight, α-actin expression and contractile response induced by the α-1adrenoceptors agonist. The relaxation induced by the NO-donor and the protein expression of endothelial nitric oxide synthase (eNOS) and soluble guanylate cyclase (sGC) were significantly decreased in the prostate of obese mice. The treatment with 5-AZA reverted the higher expression of α-actin, reduced the hypercontractility state of the prostate and increased the expression of eNOS and sGC and intraprostatic levels of cGMP. When prostates from obese mice treated with 5-AZA were incubated in vitro with inhibitors of the NOS or sGC, the inhibitory effect of 5-AZA was reverted, therefore, showing the involvement of NO and cGMP. In conclusion, our study paves the way to develop or repurpose therapies that recover the expression of eNOS and sGC and, hence, to improve prostate function in BPH.
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Affiliation(s)
- Ana Carolina Ghezzi
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Gabriela Reolon Passos
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Mariana Gonçalves de Oliveira
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Akila Lara Oliveira
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Guilherme Rossi Assis-Mendonça
- Department of Pathology, Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
- National Academy of Medicine, Young Leadership Physician Program, Rio de Janeiro, Brazil
| | - Glaucia Coelho de Mello
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Edson Antunes
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
| | - Fabiola Zakia Monica
- Department of Translation Medicine (Pharmacology area), Faculty of Medical Sciences, University of Campinas (Unicamp), Campinas, Brazil
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3
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Thalwieser Z, Fonódi M, Király N, Csortos C, Boratkó A. PP2A Affects Angiogenesis via Its Interaction with a Novel Phosphorylation Site of TSP1. Int J Mol Sci 2024; 25:1844. [PMID: 38339122 PMCID: PMC10855381 DOI: 10.3390/ijms25031844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 01/30/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024] Open
Abstract
Alterations in angiogenic properties play a pivotal role in the manifestation and onset of various pathologies, including vascular diseases and cancer. Thrombospondin-1 (TSP1) protein is one of the master regulators of angiogenesis. This study unveils a novel aspect of TSP1 regulation through reversible phosphorylation. The silencing of the B55α regulatory subunit of protein phosphatase 2A (PP2A) in endothelial cells led to a significant decrease in TSP1 expression. Direct interaction between TSP1 and PP2A-B55α was confirmed via various methods. Truncated TSP1 constructs were employed to identify the phosphorylation site and the responsible kinase, ultimately pinpointing PKC as the enzyme phosphorylating TSP1 on Ser93. The biological effects of B55α-TSP1 interaction were also analyzed. B55α silencing not only counteracted the increase in TSP1 expression during wound closure but also prolonged wound closure time. Although B55α silenced cells initiated tube-like structures earlier than control cells, their spheroid formation was disrupted, leading to disintegration. Cells transfected with phosphomimic TSP1 S93D exhibited smaller spheroids and reduced effectiveness in tube formation, revealing insights into the effects of TSP1 phosphorylation on angiogenic properties. In this paper, we introduce a new regulatory mechanism of angiogenesis by reversible phosphorylation on TSP1 S93 by PKC and PP2A B55α.
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Affiliation(s)
| | | | | | | | - Anita Boratkó
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary; (Z.T.); (M.F.); (C.C.)
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4
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Patil RS, Kovacs-Kasa A, Gorshkov BA, Fulton DJR, Su Y, Batori RK, Verin AD. Serine/Threonine Protein Phosphatases 1 and 2A in Lung Endothelial Barrier Regulation. Biomedicines 2023; 11:1638. [PMID: 37371733 PMCID: PMC10296329 DOI: 10.3390/biomedicines11061638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/28/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Vascular barrier dysfunction is characterized by increased permeability and inflammation of endothelial cells (ECs), which are prominent features of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and sepsis, and a major complication of the SARS-CoV-2 infection and COVID-19. Functional impairment of the EC barrier and accompanying inflammation arises due to microbial toxins and from white blood cells of the lung as part of a defensive action against pathogens, ischemia-reperfusion or blood product transfusions, and aspiration syndromes-based injury. A loss of barrier function results in the excessive movement of fluid and macromolecules from the vasculature into the interstitium and alveolae resulting in pulmonary edema and collapse of the architecture and function of the lungs, and eventually culminates in respiratory failure. Therefore, EC barrier integrity, which is heavily dependent on cytoskeletal elements (mainly actin filaments, microtubules (MTs), cell-matrix focal adhesions, and intercellular junctions) to maintain cellular contacts, is a critical requirement for the preservation of lung function. EC cytoskeletal remodeling is regulated, at least in part, by Ser/Thr phosphorylation/dephosphorylation of key cytoskeletal proteins. While a large body of literature describes the role of phosphorylation of cytoskeletal proteins on Ser/Thr residues in the context of EC barrier regulation, the role of Ser/Thr dephosphorylation catalyzed by Ser/Thr protein phosphatases (PPases) in EC barrier regulation is less documented. Ser/Thr PPases have been proposed to act as a counter-regulatory mechanism that preserves the EC barrier and opposes EC contraction. Despite the importance of PPases, our knowledge of the catalytic and regulatory subunits involved, as well as their cellular targets, is limited and under-appreciated. Therefore, the goal of this review is to discuss the role of Ser/Thr PPases in the regulation of lung EC cytoskeleton and permeability with special emphasis on the role of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) as major mammalian Ser/Thr PPases. Importantly, we integrate the role of PPases with the structural dynamics of the cytoskeleton and signaling cascades that regulate endothelial cell permeability and inflammation.
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Affiliation(s)
- Rahul S. Patil
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Anita Kovacs-Kasa
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Boris A. Gorshkov
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - David J. R. Fulton
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Department of Pharmacology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Yunchao Su
- Department of Pharmacology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Robert K. Batori
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Alexander D. Verin
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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Phosphate and Endothelial Function: How Sensing of Elevated Inorganic Phosphate Concentration Generates Signals in Endothelial Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1362:85-98. [DOI: 10.1007/978-3-030-91623-7_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Surendran A, Forbes Dewey C, Low BC, Tucker-Kellogg L. A computational model of mutual antagonism in the mechano-signaling network of RhoA and nitric oxide. BMC Mol Cell Biol 2021; 22:47. [PMID: 34635055 PMCID: PMC8507106 DOI: 10.1186/s12860-021-00383-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 08/23/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND RhoA is a master regulator of cytoskeletal contractility, while nitric oxide (NO) is a master regulator of relaxation, e.g., vasodilation. There are multiple forms of cross-talk between the RhoA/ROCK pathway and the eNOS/NO/cGMP pathway, but previous work has not studied their interplay at a systems level. Literature review suggests that the majority of their cross-talk interactions are antagonistic, which motivates us to ask whether the RhoA and NO pathways exhibit mutual antagonism in vitro, and if so, to seek the theoretical implications of their mutual antagonism. RESULTS Experiments found mutual antagonism between RhoA and NO in epithelial cells. Since mutual antagonism is a common motif for bistability, we sought to explore through theoretical simulations whether the RhoA-NO network is capable of bistability. Qualitative modeling showed that there are parameters that can cause bistable switching in the RhoA-NO network, and that the robustness of the bistability would be increased by positive feedback between RhoA and mechanical tension. CONCLUSIONS We conclude that the RhoA-NO bistability is robust enough in silico to warrant the investment of further experimental testing. Tension-dependent bistability has the potential to create sharp concentration gradients, which could contribute to the localization and self-organization of signaling domains during cytoskeletal remodeling and cell migration.
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Affiliation(s)
- Akila Surendran
- Singapore-MIT Alliance, Computational Systems Biology Programme, National University of Singapore, Singapore, Singapore.,Centre for Assistive Technology & Innovation, National Institute of Speech & Hearing, Trivandrum, Kerala, India
| | - C Forbes Dewey
- Singapore-MIT Alliance, Computational Systems Biology Programme, National University of Singapore, Singapore, Singapore.,Biological Engineering and Mechanical Engineering Departments, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Boon Chuan Low
- Singapore-MIT Alliance, Computational Systems Biology Programme, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,Mechanobiology Institute, National University of Singapore, Singapore, Singapore.,University Scholars Programme, National University of Singapore, Singapore, Singapore
| | - Lisa Tucker-Kellogg
- Singapore-MIT Alliance, Computational Systems Biology Programme, National University of Singapore, Singapore, Singapore. .,Cancer and Stem Cell Biology, and Centre for Computational Biology, Duke-NUS Medical School, Singapore, Singapore.
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7
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Qin A, Chen S, Wang P, Huang X, Zhang Y, Liang L, Du LR, Lai DH, Ding L, Yu X, Xiang AP. Knockout of NOS2 Promotes Adipogenic Differentiation of Rat MSCs by Enhancing Activation of JAK/STAT3 Signaling. Front Cell Dev Biol 2021; 9:638518. [PMID: 33816486 PMCID: PMC8017136 DOI: 10.3389/fcell.2021.638518] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 02/08/2021] [Indexed: 12/14/2022] Open
Abstract
Mesenchymal stromal cells (MSCs) are a heterogeneous population of cells that possess multilineage differentiation potential and extensive immunomodulatory properties. In mice and rats, MSCs produce nitric oxide (NO), as immunomodulatory effector molecule that exerts an antiproliferative effect on T cells, while the role of NO in differentiation was less clear. Here, we investigated the role of NO synthase 2 (NOS2) on adipogenic and osteogenic differentiation of rat MSCs. MSCs isolated from NOS2-null (NOS2–/–) and wild type (WT) Sprague–Dawley (SD) rats exhibited homogenous fibroblast-like morphology and characteristic phenotypes. However, after induction, adipogenic differentiation was found significantly promoted in NOS2–/– MSCs compared to WT MSCs, but not in osteogenic differentiation. Accordingly, qRT-PCR revealed that the adipogenesis-related genes PPAR-γ, C/EBP-α, LPL and FABP4 were markedly upregulated in NOS2–/– MSCs, but not for osteogenic transcription factors or marker genes. Further investigations revealed that the significant enhancement of adipogenic differentiation in NOS2–/– MSCs was due to overactivation of the STAT3 signaling pathway. Both AG490 and S3I-201, small molecule inhibitors that selectively inhibit STAT3 activation, reversed this adipogenic effect. Furthermore, after high-fat diet (HFD) feeding, knockout of NOS2 in rat MSCs resulted in significant obesity. In summary, NOS2 is involved in the regulation of rat MSC adipogenic differentiation via the STAT3 signaling pathway.
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Affiliation(s)
- Aiping Qin
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Sheng Chen
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Ping Wang
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Xiaotao Huang
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Yu Zhang
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Lu Liang
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Ling-Ran Du
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - De-Hua Lai
- Center for Parasitic Organisms, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Li Ding
- Department of Pathology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiyong Yu
- Key Laboratory of Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, The Fifth Affiliated Hospital, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, China
| | - Andy Peng Xiang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China
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Reina-Torres E, De Ieso ML, Pasquale LR, Madekurozwa M, van Batenburg-Sherwood J, Overby DR, Stamer WD. The vital role for nitric oxide in intraocular pressure homeostasis. Prog Retin Eye Res 2020; 83:100922. [PMID: 33253900 DOI: 10.1016/j.preteyeres.2020.100922] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023]
Abstract
Catalyzed by endothelial nitric oxide (NO) synthase (eNOS) activity, NO is a gaseous signaling molecule maintaining endothelial and cardiovascular homeostasis. Principally, NO regulates the contractility of vascular smooth muscle cells and permeability of endothelial cells in response to either biochemical or biomechanical cues. In the conventional outflow pathway of the eye, the smooth muscle-like trabecular meshwork (TM) cells and Schlemm's canal (SC) endothelium control aqueous humor outflow resistance, and therefore intraocular pressure (IOP). The mechanisms by which outflow resistance is regulated are complicated, but NO appears to be a key player as enhancement or inhibition of NO signaling dramatically affects outflow function; and polymorphisms in NOS3, the gene that encodes eNOS modifies the relation between various environmental exposures and glaucoma. Based upon a comprehensive review of past foundational studies, we present a model whereby NO controls a feedback signaling loop in the conventional outflow pathway that is sensitive to changes in IOP and its oscillations. Thus, upon IOP elevation, the outflow pathway tissues distend, and the SC lumen narrows resulting in increased SC endothelial shear stress and stretch. In response, SC cells upregulate the production of NO, relaxing neighboring TM cells and increasing permeability of SC's inner wall. These IOP-dependent changes in the outflow pathway tissues reduce the resistance to aqueous humor drainage and lower IOP, which, in turn, diminishes the biomechanical signaling on SC. Similar to cardiovascular pathogenesis, dysregulation of the eNOS/NO system leads to dysfunctional outflow regulation and ocular hypertension, eventually resulting in primary open-angle glaucoma.
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Affiliation(s)
| | | | - Louis R Pasquale
- Eye and Vision Research Institute of New York Eye and Ear Infirmary at Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | | | - Darryl R Overby
- Department of Bioengineering, Imperial College London, London, UK.
| | - W Daniel Stamer
- Department of Ophthalmology, Duke University, Durham, NC, USA.
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9
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Łuczak A, Madej M, Kasprzyk A, Doroszko A. Role of the eNOS Uncoupling and the Nitric Oxide Metabolic Pathway in the Pathogenesis of Autoimmune Rheumatic Diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:1417981. [PMID: 32351667 PMCID: PMC7174952 DOI: 10.1155/2020/1417981] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/31/2020] [Indexed: 12/15/2022]
Abstract
Atherosclerosis and its clinical complications constitute the major healthcare problems of the world population. Due to the central role of endothelium throughout the atherosclerotic disease process, endothelial dysfunction is regarded as a common mechanism for various cardiovascular (CV) disorders. It is well established that patients with rheumatic autoimmune diseases are characterized by significantly increased prevalence of cardiovascular morbidity and mortality compared with the general population. The current European guidelines on cardiovascular disease (CVD) prevention in clinical practice recommend to use a 1,5-factor multiplier for CV risk in rheumatoid arthritis as well as in other autoimmune inflammatory diseases. However, mechanisms of accelerated atherosclerosis in these diseases, especially in the absence of traditional risk factors, still remain unclear. Oxidative stress plays the major role in the endothelial dysfunction and recently is strongly attributed to endothelial NO synthase dysfunction (eNOS uncoupling). Converted to a superoxide-producing enzyme, uncoupled eNOS not only leads to reduction of the nitric oxide (NO) generation but also potentiates the preexisting oxidative stress, which contributes significantly to atherogenesis. However, to date, there are no systemic analyses on the role of eNOS uncoupling in the excess CV mortality linked with autoimmune rheumatic diseases. The current review paper addresses this issue.
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Affiliation(s)
- Anna Łuczak
- Department of Rheumatology, Wroclaw Medical University, Poland
| | - Marta Madej
- Department of Rheumatology, Wroclaw Medical University, Poland
| | - Agata Kasprzyk
- Department of Rheumatology, Wroclaw Medical University, Poland
| | - Adrian Doroszko
- Department of Internal Medicine, Hypertension and Clinical Oncology, Wroclaw Medical University, Poland
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10
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Li Y, Talotta-Altenburg LM, Silimperi KA, Ciabattoni GO, Lowe-Krentz LJ. Endothelial nitric oxide synthase activation is required for heparin receptor effects on vascular smooth muscle cells. Am J Physiol Cell Physiol 2019; 318:C463-C475. [PMID: 31891520 DOI: 10.1152/ajpcell.00284.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Published studies indicate that TMEM184A is a heparin receptor that interacts with and transduces stimulation from heparin in vascular cells. Previous studies have indicated that heparin increases endothelial nitric oxide synthase (eNOS) activity in bovine endothelial cells. However, the precise mechanism remains unknown. In this study, we investigated the impact of heparin treatment and TMEM184A on eNOS's activation and the role of eNOS in heparin signaling in the cloned A7r5 rat vascular smooth muscle cell line and confirmed results in endothelial cells. We employed a combination of TMEM184A knockdown A7r5 cells along with transient eNOS knockdown and enzyme inhibitor strategies. The results indicate that heparin induces phosphorylation of eNOS. eNOS can be immunoprecipitated with TMEM184A and is internalized to the perinuclear region in a TMEM184A-dependent manner in response to heparin. We also examined how heparin treatment leads to phosphorylation of eNOS and confirmed that TMEM184A and Ca2+ were required to mediate heparin-elicited eNOS phosphorylation. Evidence supporting the involvement of transient receptor potential cation channel subfamily V member 4 with TMEM184A in this eNOS activation process is also presented.
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Affiliation(s)
- Yaqiu Li
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
| | | | - Kayli A Silimperi
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
| | - Grace O Ciabattoni
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
| | - Linda J Lowe-Krentz
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
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11
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Cho DH. Telmisartan Inhibits Nitric Oxide Production and Vessel Relaxation via Protein Phosphatase 2A-mediated Endothelial NO Synthase-Ser 1179 Dephosphorylation. J Korean Med Sci 2019; 34:e266. [PMID: 31674157 PMCID: PMC6823522 DOI: 10.3346/jkms.2019.34.e266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Apart from its blood pressure-lowering effect by blocking the renin-angiotensin-aldosterone system, telmisartan, an angiotensin II type 1 receptor blocker (ARB), exhibits various ancillary effects including cardiovascular protective effects in vitro. Nonetheless, the protective effects of telmisartan in cerebrocardiovascular diseases are somewhat variable in large-scale clinical trials. Dysregulation of endothelial nitric oxide (NO) synthase (eNOS)-derived NO contributes to the developments of various vascular diseases. Nevertheless, the direct effects of telmisartan on endothelial functions including NO production and vessel relaxation, and its action mechanism have not been fully elucidated. Here, we investigated the mechanism by which telmisartan regulates NO production and vessel relaxation in vitro and in vivo. METHODS We measured nitrite levels in culture medium and mouse serum, and performed inhibitor studies and western blot analyses using bovine aortic endothelial cells (BAECs) and a hyperglycemic mouse model. To assess vessel reactivity, we performed acetylcholine (ACh)-induced vessel relaxation assay on isolated rat aortas. RESULTS Telmisartan decreased NO production in normoglycemic and hyperglycemic BAECs, which was accompanied by reduced phosphorylation of eNOS at Ser1179 (p-eNOS-Ser1179). Telmisartan increased the expression of protein phosphatase 2A catalytic subunit (PP2Ac) and co-treatment with okadaic acid completely restored telmisartan-inhibited NO production and p-eNOS-Ser1179 levels. Of the ARBs tested (including losartan and fimasartan), only telmisartan decreased NO production and p-eNOS-Ser1179 levels, and enhanced PP2Ac expression. Co-treatment with GW9662 had no effect on telmisartan-induced changes. In line with in vitro observations, telmisartan reduced serum nitrite and p-eNOS-Ser1179 levels, and increased PP2Ac expression in high fat diet-fed mice. Furthermore, telmisartan attenuated ACh-induced rat aorta relaxation. CONCLUSION We demonstrated that telmisartan inhibited NO production and vessel relaxation at least in part by PP2A-mediated eNOS-Ser1179 dephosphorylation in a peroxisome proliferator-activated receptor γ-independent manner. These results may provide a mechanism that explains the inconsistent cerebrocardiovascular protective effects of telmisartan.
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Affiliation(s)
- Du Hyong Cho
- Department of Pharmacology, Yeungnam University College of Medicine, Daegu, Korea.
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12
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Luo W, Wang Y, Yang H, Dai C, Hong H, Li J, Liu Z, Guo Z, Chen X, He P, Li Z, Li F, Jiang J, Liu P, Li Z. Heme oxygenase-1 ameliorates oxidative stress-induced endothelial senescence via regulating endothelial nitric oxide synthase activation and coupling. Aging (Albany NY) 2019; 10:1722-1744. [PMID: 30048241 PMCID: PMC6075439 DOI: 10.18632/aging.101506] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 07/20/2018] [Indexed: 12/20/2022]
Abstract
AIM Premature senescence of vascular endothelial cells is a leading cause of various cardiovascular diseases. Therapies targeting endothelial senescence would have important clinical implications. The present study was aimed to evaluate the potential of heme oxygenase-1 (HO-1) as a therapeutic target for endothelial senescence. METHODS AND RESULTS Upregulation of HO-1 by Hemin or adenovirus infection reversed H2O2-induced senescence in human umbilical vein endothelial cells (HUVECs); whereas depletion of HO-1 by siRNA or HO-1 inhibitor protoporphyrin IX zinc (II) (ZnPP) triggered HUVEC senescence. Mechanistically, overexpression of HO-1 enhanced the interaction between HO-1 and endothelial nitric oxide synthase (eNOS), and promoted the interaction between eNOS and its upstream kinase Akt, thus resulting in an enhancement of eNOS phosphorylation at Ser1177 and a subsequent increase of nitric oxide (NO) production. Moreover, HO-1 induction prevented the decrease of eNOS dimer/monomer ratio stimulated by H2O2 via its antioxidant properties. Contrarily, HO-1 silencing impaired eNOS phosphorylation and accelerated eNOS uncoupling. In vivo, Hemin treatment alleviated senescence of endothelial cells of the aorta from spontaneously hypertensive rats, through upregulating eNOS phosphorylation at Ser1177. CONCLUSIONS HO-1 ameliorated endothelial senescence through enhancing eNOS activation and defending eNOS uncoupling, suggesting that HO-1 is a potential target for treating endothelial senescence.
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Affiliation(s)
- Wenwei Luo
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Yu Wang
- Infinitus (China) Co. Ltd, Guangzhou 510663, China
| | - Hanwei Yang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Chunmei Dai
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Huiling Hong
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Jingyan Li
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Zhiping Liu
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Zhen Guo
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Xinyi Chen
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Ping He
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Ziqing Li
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Fang Li
- College of Life Science, South China Agricultural University, Guangzhou 510642, China
| | - Jianmin Jiang
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Peiqing Liu
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
| | - Zhuoming Li
- Laboratory of Pharmacology and Toxicology, School of Pharmaceutical Sciences; National and Local United Engineering Lab of Druggability and New Drugs Evaluation; Guangdong Provincial Key Laboratory of New Drug Design and Evaluation, Sun Yat-sen University, Guangzhou, 510006, China
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13
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Becerril S, Rodríguez A, Catalán V, Ramírez B, Unamuno X, Portincasa P, Gómez-Ambrosi J, Frühbeck G. Functional Relationship between Leptin and Nitric Oxide in Metabolism. Nutrients 2019; 11:nu11092129. [PMID: 31500090 PMCID: PMC6769456 DOI: 10.3390/nu11092129] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/23/2019] [Accepted: 09/02/2019] [Indexed: 12/28/2022] Open
Abstract
Leptin, the product of the ob gene, was originally described as a satiety factor, playing a crucial role in the control of body weight. Nevertheless, the wide distribution of leptin receptors in peripheral tissues supports that leptin exerts pleiotropic biological effects, consisting of the modulation of numerous processes including thermogenesis, reproduction, angiogenesis, hematopoiesis, osteogenesis, neuroendocrine, and immune functions as well as arterial pressure control. Nitric oxide (NO) is a free radical synthesized from L-arginine by the action of the NO synthase (NOS) enzyme. Three NOS isoforms have been identified: the neuronal NOS (nNOS) and endothelial NOS (eNOS) constitutive isoforms, and the inducible NOS (iNOS). NO mediates multiple biological effects in a variety of physiological systems such as energy balance, blood pressure, reproduction, immune response, or reproduction. Leptin and NO on their own participate in multiple common physiological processes, with a functional relationship between both factors having been identified. The present review describes the functional relationship between leptin and NO in different physiological processes.
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Affiliation(s)
- Sara Becerril
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Amaia Rodríguez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Victoria Catalán
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Beatriz Ramírez
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Xabier Unamuno
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Medical Engineering Laboratory, University of Navarra, 31008 Pamplona, Spain.
| | - Piero Portincasa
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Policlinico Hospital, 70124 Bari, Italy.
| | - Javier Gómez-Ambrosi
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
| | - Gema Frühbeck
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 31008 Pamplona, Spain.
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain.
- Department of Endocrinology & Nutrition, Clínica Universidad de Navarra, 31008 Pamplona, Spain.
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14
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Luo Y, Zhang Q, Ding J, Yu M, Jiang J, Yang F, Wang S, Wang A, Wang L, Wu S, Xia Y, Lu D. Roles of I 2PP2A in the downregulation of eNOS Ser1177 phosphorylation by angiotensin II-activated PP2A. Biochem Biophys Res Commun 2019; 516:613-618. [PMID: 31239152 DOI: 10.1016/j.bbrc.2019.06.063] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 06/12/2019] [Indexed: 12/13/2022]
Abstract
The chronic elevation of angiotensin II (Ang II) is an important cause of endothelial dysfunction (ED). The Ang II/type 1 receptor (AT1R) signaling pathway can cause endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) dysfunction through various mechanisms leading to ED. The modulation of eNOS phosphorylated at Ser1177 is an important mechanism upregulating eNOS activity. Protein phosphatase 2 A (PP2A) has been reported to dephosphorylate eNOS at Ser1177. The PP2A inhibitor 2 protein (I2PP2A) is a specific endogenous inhibitor that binds the catalytic subunit of PP2A and directly inhibits PP2A activity. Therefore, we hypothesized that Ang II might attenuate I2PP2A expression to activate PP2A, which downregulates eNOS Ser 1177 phosphorylation, leading to eNOS dysfunction. In our study, we used Ang II-treated human umbilical vein endothelial cells (HUVECs) and, found that the eNOS Ser1177 phosphorylation levels were downregulated, the activity of PP2A was increased, and I2PP2A expression was decreased. Furthermore, these effects were blocked by candesartan (CAN). The phosphorylation levels of eNOS Ser1177 were decreased after I2PP2A was knocked down by specific siRNA but increased after I2PP2A overexpression. We also found that the Ang II treatment decreased the association of I2PP2A with PP2A but increased the association between PP2A and eNOS. Taken together, our results suggest that Ang II activates PP2A by downregulating the I2PP2A expression through the AT1R signaling pathway leading to the loss of eNOS Ser1177 phosphorylation and ED.
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Affiliation(s)
- Yanbei Luo
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Qian Zhang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Jing Ding
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Min Yu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Juncai Jiang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Fei Yang
- Department of Cardiology, The Second Provincial People's Hospital of Gansu, Lanzhou, Gansu, China
| | - Shengnan Wang
- Department of Pathology, The Second Clinical Medical School of Inner Mongolia University for the Nationalities, Yakeshi, Inner Mongolia, China
| | - Alei Wang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Lingxiao Wang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China
| | - Shan Wu
- Department of Neurology, Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Yong Xia
- Davis Heart & Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA.
| | - Deqin Lu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China; Guizhou Provincial Key Laboratory of Pathogenesis & Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China.
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15
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Kishor DS, Lee C, Lee D, Venkatesh J, Seo J, Chin JH, Jin Z, Hong SK, Ham JK, Koh HJ. Novel allelic variant of Lpa1 gene associated with a significant reduction in seed phytic acid content in rice (Oryza sativa L.). PLoS One 2019; 14:e0209636. [PMID: 30870429 PMCID: PMC6417671 DOI: 10.1371/journal.pone.0209636] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/19/2019] [Indexed: 01/26/2023] Open
Abstract
In plants, myo-inositol-1,2,3,4,5,6-hexakisphosphate (InsP6), also known as phytic acid (PA), is a major component of organic phosphorus (P), and accounts for up to 85% of the total P in seeds. In rice (Oryza sativa L.), PA mainly accumulates in rice bran, and chelates mineral cations, resulting in mineral deficiencies among brown rice consumers. Therefore, considerable efforts have been focused on the development of low PA (LPA) rice cultivars. In this study, we performed genetic and molecular analyses of OsLpa1, a major PA biosynthesis gene, in Sanggol, a low PA mutant variety developed via chemical mutagenesis of Ilpum rice cultivar. Genetic segregation and sequencing analyses revealed that a recessive allele, lpa1-3, at the OsLpa1 locus (Os02g0819400) was responsible for a significant reduction in seed PA content in Sanggol. The lpa1-3 gene harboured a point mutation (C623T) in the fourth exon of the predicted coding region, resulting in threonine (Thr) to isoleucine (Ile) amino acidsubstitution at position 208 (Thr208Ile). Three-dimensional analysis of Lpa1 protein structure indicated that myo-inositol 3-monophosphate [Ins(3)P1] could bind to the active site of Lpa1, with ATP as a cofactor for catalysis. Furthermore, the presence of Thr208 in the loop adjacent to the entry site of the binding pocket suggests that Thr208Ile substitution is involved in regulating enzyme activity via phosphorylation. Therefore, we propose that Thr208Ile substitution in lpa1-3 reduces Lpa1 enzyme activity in Sanggol, resulting in reduced PA biosynthesis.
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Affiliation(s)
- D. S. Kishor
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Choonseok Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Dongryung Lee
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Jelli Venkatesh
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Jeonghwan Seo
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Joong Hyoun Chin
- Graduate School of Integrated Bioindustry, Sejong University, Seoul, Republic of Korea
| | - Zhuo Jin
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
| | - Soon-Kwan Hong
- Division of Biotechnology, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
| | - Jin-Kwan Ham
- Gangwon provincial Agricultural Research & Extension Services, Chuncheon, Gangwon-do, Republic of Korea
| | - Hee Jong Koh
- Department of Plant Science, Plant Genomics and Breeding Institute, and Research Institute of Agriculture and Life Science, Seoul National University, Seoul, Republic of Korea
- * E-mail:
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16
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Lin Q, Zhao L, Jing R, Trexler C, Wang H, Li Y, Tang H, Huang F, Zhang F, Fang X, Liu J, Jia N, Chen J, Ouyang K. Inositol 1,4,5-Trisphosphate Receptors in Endothelial Cells Play an Essential Role in Vasodilation and Blood Pressure Regulation. J Am Heart Assoc 2019; 8:e011704. [PMID: 30755057 PMCID: PMC6405661 DOI: 10.1161/jaha.118.011704] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/17/2019] [Indexed: 01/06/2023]
Abstract
Background Endothelial NO synthase plays a central role in regulating vasodilation and blood pressure. Intracellular Ca2+ mobilization is a critical modulator of endothelial NO synthase function, and increased cytosolic Ca2+ concentration in endothelial cells is able to induce endothelial NO synthase phosphorylation. Ca2+ release mediated by 3 subtypes of inositol 1,4,5-trisphosphate receptors ( IP 3Rs) from the endoplasmic reticulum and subsequent Ca2+ entry after endoplasmic reticulum Ca2+ store depletion has been proposed to be the major pathway to mobilize Ca2+ in endothelial cells. However, the physiological role of IP 3Rs in regulating blood pressure remains largely unclear. Methods and Results To investigate the role of endothelial IP 3Rs in blood pressure regulation, we first generated an inducible endothelial cell-specific IP 3R1 knockout mouse model and found that deletion of IP 3R1 in adult endothelial cells did not affect vasodilation and blood pressure. Considering all 3 subtypes of IP 3Rs are expressed in mouse endothelial cells, we further generated inducible endothelial cell-specific IP 3R triple knockout mice and found that deletion of all 3 IP 3R subtypes decreased plasma NO concentration and increased basal blood pressure. Furthermore, IP 3R deficiency reduced acetylcholine-induced vasodilation and endothelial NO synthase phosphorylation at Ser1177. Conclusions Our results reveal that IP 3R-mediated Ca2+ release in vascular endothelial cells plays an important role in regulating vasodilation and physiological blood pressure.
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MESH Headings
- Animals
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/pathology
- Aorta, Thoracic/physiopathology
- Blood Pressure/physiology
- Calcium/metabolism
- Disease Models, Animal
- Endothelial Cells/metabolism
- Endothelial Cells/pathology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiopathology
- Hypertension/metabolism
- Hypertension/pathology
- Hypertension/physiopathology
- Immunoblotting
- Inositol 1,4,5-Trisphosphate Receptors/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myography
- Vasodilation/physiology
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Affiliation(s)
- Qingsong Lin
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Lingyun Zhao
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Ran Jing
- Department of CardiologyThe Second Xiangya HospitalCentral South UniversityChangshaHunanChina
| | - Christa Trexler
- Department of MedicineSchool of MedicineUniversity of California San DiegoLa JollaCA
| | - Hong Wang
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Yali Li
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Huayuan Tang
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Fang Huang
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Fei Zhang
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
| | - Xi Fang
- Department of MedicineSchool of MedicineUniversity of California San DiegoLa JollaCA
| | - Jie Liu
- Department of PathophysiologySchool of MedicineShenzhen UniversityShenzhenChina
| | - Nan Jia
- Department of CardiologyThe Eighth Affiliated HospitalSun Yat‐sen UniversityShenzhenChina
| | - Ju Chen
- Department of MedicineSchool of MedicineUniversity of California San DiegoLa JollaCA
| | - Kunfu Ouyang
- Drug Discovery CenterState Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenChina
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17
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Vauzour D, Corsini S, Müller M, Spencer JP. Inhibition of PP2A by hesperetin may contribute to Akt and ERK1/2 activation status in cortical neurons. Arch Biochem Biophys 2018; 650:14-21. [DOI: 10.1016/j.abb.2018.04.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/27/2018] [Accepted: 04/29/2018] [Indexed: 01/09/2023]
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18
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Antiphospholipid antibodies induce thrombosis by PP2A activation via apoER2-Dab2-SHC1 complex formation in endothelium. Blood 2018; 131:2097-2110. [PMID: 29500169 DOI: 10.1182/blood-2017-11-814681] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 02/23/2018] [Indexed: 01/10/2023] Open
Abstract
In the antiphospholipid syndrome (APS), antiphospholipid antibody (aPL) recognition of β2 glycoprotein I promotes thrombosis, and preclinical studies indicate that this is due to endothelial nitric oxide synthase (eNOS) antagonism via apolipoprotein E receptor 2 (apoER2)-dependent processes. How apoER2 molecularly links these events is unknown. Here, we show that, in endothelial cells, the apoER2 cytoplasmic tail serves as a scaffold for aPL-induced assembly and activation of the heterotrimeric protein phosphatase 2A (PP2A). Disabled-2 (Dab2) recruitment to the apoER2 NPXY motif promotes the activating L309 methylation of the PP2A catalytic subunit by leucine methyl transferase-1. Concurrently, Src homology domain-containing transforming protein 1 (SHC1) recruits the PP2A scaffolding subunit to the proline-rich apoER2 C terminus along with 2 distinct regulatory PP2A subunits that mediate inhibitory dephosphorylation of Akt and eNOS. In mice, the coupling of these processes in endothelium is demonstrated to underlie aPL-invoked thrombosis. By elucidating these intricacies in the pathogenesis of APS-related thrombosis, numerous potential new therapeutic targets have been identified.
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19
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Antiphospholipid Syndrome: Role of Vascular Endothelial Cells and Implications for Risk Stratification and Targeted Therapeutics. J Am Coll Cardiol 2017; 69:2317-2330. [PMID: 28473138 DOI: 10.1016/j.jacc.2017.02.058] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/21/2017] [Accepted: 02/28/2017] [Indexed: 12/28/2022]
Abstract
Antiphospholipid syndrome (APS) is an autoimmune disease characterized by venous thromboembolism, arterial thrombosis, and obstetric morbidities in the setting of persistently positive levels of antiphospholipid antibodies measured on 2 different occasions 12 weeks apart. Patients with APS are at increased risk for accelerated atherosclerosis, myocardial infarction, stroke, and valvular heart disease. Vascular endothelial cell dysfunction mediated by antiphospholipid antibodies and subsequent complement system activation play a cardinal role in APS pathogenesis. Improved understanding of their pathogenic function could help in the risk stratification of patients with APS and provide new molecular therapeutic targets.
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20
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Shear-Induced Nitric Oxide Production by Endothelial Cells. Biophys J 2017; 111:208-21. [PMID: 27410748 DOI: 10.1016/j.bpj.2016.05.034] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 04/30/2016] [Accepted: 05/23/2016] [Indexed: 02/06/2023] Open
Abstract
We present a biochemical model of the wall shear stress-induced activation of endothelial nitric oxide synthase (eNOS) in an endothelial cell. The model includes three key mechanotransducers: mechanosensing ion channels, integrins, and G protein-coupled receptors. The reaction cascade consists of two interconnected parts. The first is rapid activation of calcium, which results in formation of calcium-calmodulin complexes, followed by recruitment of eNOS from caveolae. The second is phosphorylation of eNOS by protein kinases PKC and AKT. The model also includes a negative feedback loop due to inhibition of calcium influx into the cell by cyclic guanosine monophosphate (cGMP). In this feedback, increased nitric oxide (NO) levels cause an increase in cGMP levels, so that cGMP inhibition of calcium influx can limit NO production. The model was used to predict the dynamics of NO production by an endothelial cell subjected to a step increase of wall shear stress from zero to a finite physiologically relevant value. Among several experimentally observed features, the model predicts a highly nonlinear, biphasic transient behavior of eNOS activation and NO production: a rapid initial activation due to the very rapid influx of calcium into the cytosol (occurring within 1-5 min) is followed by a sustained period of activation due to protein kinases.
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21
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Ghimire K, Altmann HM, Straub AC, Isenberg JS. Nitric oxide: what's new to NO? Am J Physiol Cell Physiol 2016; 312:C254-C262. [PMID: 27974299 PMCID: PMC5401944 DOI: 10.1152/ajpcell.00315.2016] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 12/12/2016] [Accepted: 12/12/2016] [Indexed: 01/22/2023]
Abstract
Nitric oxide (NO) is one of the critical components of the vasculature, regulating key signaling pathways in health. In macrovessels, NO functions to suppress cell inflammation as well as adhesion. In this way, it inhibits thrombosis and promotes blood flow. It also functions to limit vessel constriction and vessel wall remodeling. In microvessels and particularly capillaries, NO, along with growth factors, is important in promoting new vessel formation, a process termed angiogenesis. With age and cardiovascular disease, animal and human studies confirm that NO is dysregulated at multiple levels including decreased production, decreased tissue half-life, and decreased potency. NO has also been implicated in diseases that are related to neurotransmission and cancer although it is likely that these processes involve NO at higher concentrations and from nonvascular cell sources. Conversely, NO and drugs that directly or indirectly increase NO signaling have found clinical applications in both age-related diseases and in younger individuals. This focused review considers recently reported advances being made in the field of NO signaling regulation at several levels including enzymatic production, receptor function, interacting partners, localization of signaling, matrix-cellular and cell-to-cell cross talk, as well as the possible impact these newly described mechanisms have on health and disease.
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Affiliation(s)
- Kedar Ghimire
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Helene M Altmann
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Adam C Straub
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Jeffrey S Isenberg
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania; .,Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania; and.,Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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22
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Estrogen Receptor Signaling and the PI3K/Akt Pathway Are Involved in Betulinic Acid-Induced eNOS Activation. Molecules 2016; 21:molecules21080973. [PMID: 27463705 PMCID: PMC6273205 DOI: 10.3390/molecules21080973] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/20/2016] [Accepted: 07/21/2016] [Indexed: 11/16/2022] Open
Abstract
Betulinic acid (BA) is a naturally occurring pentacyclic triterpenoid with anti-inflammatory, antiviral and anti-cancer properties. Beneficial cardiovascular effects such as increased nitric oxide (NO) production through enhancement of endothelial NO synthase (eNOS) activity and upregulation of eNOS expression have been demonstrated for this compound. In the present study, immortalized human EA.hy 926 endothelial cells were incubated for up to 1 h with 1–100 µM BA and with the phosphatidylinositol-3-kinase (PI3K) inhibitors LY294002 and wortmannin, or the estrogen receptor (ER) antagonist ICI 182,780. Phosphorylation status of eNOS and total eNOS protein were analyzed by Western blotting using a serine 1177 phosphosite-specific antibody. Bioactive NO production was assessed by determination of cGMP content in rat lung fibroblasts (RFL-6) reporter cells. Short-term incubation of EA.hy 926 cells with BA resulted in eNOS phosphorylation at the serine 1177 residue in a concentration- and time-dependent manner with a half-maximal effective concentration of 0.57 µM. This was associated with an enhanced production of NO. BA-induced eNOS phosphorylation and NO production was completely blocked by pretreatment with ICI 182,780, and was attenuated by pretreatment with the PI3K inhibitors wortmannin and LY294002. These results indicate that fast non-genomic effects of ER with downstream signaling through the PI3K/Akt pathway and consecutive eNOS phosphorylation at serine 1177 are involved in BA-induced eNOS activation.
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PGC-1α ameliorates AngiotensinII-induced eNOS dysfunction in human aortic endothelial cells. Vascul Pharmacol 2016; 83:90-7. [PMID: 27235860 DOI: 10.1016/j.vph.2016.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 04/29/2016] [Accepted: 05/21/2016] [Indexed: 02/05/2023]
Abstract
Increasing evidences support that PGC-1α participates in regulating endothelial homeostasis, in part by mediating endothelial nitric oxide (NO) synthase (eNOS) activity and NO production. However, the molecular mechanisms by which PGC-1α regulates eNOS activity are not completely understood. In the present study, we investigated the effects of PGC-1α on eNOS dysfunction and further explore the underlying mechanisms. The results showed that PGC-1α expression was downregulated after AngiotensinII (AngII) treatment and paralleled with the decreased NO generation in human aortic endothelial cells. Overexpression of PGC-1α with adenovirus or pharmacological agonist ameliorated AngII-induced the decrease of NO generation, evidenced by the restoration of cGMP and nitrite concentration. Rather than affecting eNOS expression and uncoupling, PGC-1α inhibited AngII-induced decrease of eNOS serine 1177 phosphorylation through activation of PI3K/Akt signaling. In addition, PGC-1α overexpression suppressed AngII-induced the increase of PP2A-A/eNOS interaction and PP2A phosphatase activity, with a concomitant decrease in PP2A phosphorylation, leading to eNOS serine 1177 phosphorylation. However, pharmacological inhibition of PI3K/Akt signaling blunted the observed effect of PGC-1α on PP2A activity. Taken together, our findings suggest that PGC-1α overexpression improves AngII-induced eNOS dysfunction and that improved eNOS dysfunction is associated with activated PI3K/Akt pathway, impaired PP2A activity and reduced PP2A-A/eNOS association. These date indicate that forced PGC-1α expression may be a novel therapeutic approach for endothelial dysfunction.
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Endothelial Microparticle-Derived Reactive Oxygen Species: Role in Endothelial Signaling and Vascular Function. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:5047954. [PMID: 27313830 PMCID: PMC4893592 DOI: 10.1155/2016/5047954] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/17/2016] [Indexed: 11/17/2022]
Abstract
Endothelial microparticles are effectors of endothelial damage; however mechanisms involved are unclear. We examined the effects of eMPs on cultured endothelial cells (ECs) and isolated vessels and investigated the role of eMP-derived reactive oxygen species (ROS) and redox signaling in these processes. eMPs were isolated from EC media and their ability to directly produce ROS was assessed by lucigenin and liquid chromatography. Nicotinamide adenine dinucleotide phosphate oxidase (Nox) subunits were probed by Western blot. ECs were treated with eMPs and effects on kinase signaling, superoxide anion (O2∙−) generation, and nitric oxide (NO) production were examined. Acetylcholine-mediated vasorelaxation was assessed by myography in eMP-treated mesenteric arteries. eMPs contained Nox1, Nox2, Nox4, p47phox, p67phox, and p22phox and they produced ROS which was inhibited by the Nox inhibitor, apocynin. eMPs increased phosphorylation of ERK1/2 and Src, increased O2∙− production, and decreased A23187-induced NO production in ECs. Pretreatment of eMPs with apocynin diminished eMP-mediated effects on ROS and NO production but had no effect on eMP-mediated kinase activation or impairment in vasorelaxation. Our findings identify a novel mechanism whereby eMP-derived ROS contributes to MP bioactivity. These interactions may be important in conditions associated with vascular injury and increased eMP formation.
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Transcriptional and Posttranslational Regulation of eNOS in the Endothelium. ADVANCES IN PHARMACOLOGY 2016; 77:29-64. [PMID: 27451094 DOI: 10.1016/bs.apha.2016.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nitric oxide (NO) is a highly reactive free radical gas and these unique properties have been adapted for a surprising number of biological roles. In neurons, NO functions as a neurotransmitter; in immune cells, NO contributes to host defense; and in endothelial cells, NO is a major regulator of blood vessel homeostasis. In the vasculature, NO is synthesized on demand by a specific enzyme, endothelial nitric oxide synthase (eNOS) that is uniquely expressed in the endothelial cells that form the interface between the circulating blood and the various tissues of the body. NO regulates endothelial and blood vessel function via two distinct pathways, the activation of soluble guanylate cyclase and cGMP-dependent signaling and the S-nitrosylation of proteins with reactive thiols (S-nitrosylation). The chemical properties of NO also serve to reduce oxidation and regulate mitochondrial function. Reduced synthesis and/or compromised biological activity of NO precede the development of cardiovascular disease and this has generated a high level of interest in the mechanisms controlling the synthesis and fate of NO in the endothelium. The amount of NO produced results from the expression level of eNOS, which is regulated at the transcriptional and posttranscriptional levels as well as the acute posttranslational regulation of eNOS. The goal of this chapter is to highlight and integrate past and current knowledge of the mechanisms regulating eNOS expression in the endothelium and the posttranslational mechanisms regulating eNOS activity in both health and disease.
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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.
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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.
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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]
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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: 480] [Impact Index Per Article: 53.3] [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.
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Li YH, Xu Q, Xu WH, Guo XH, Zhang S, Chen YD. Mechanisms of protection against diabetes-induced impairment of endothelium-dependent vasorelaxation by Tanshinone IIA. Biochim Biophys Acta Gen Subj 2015; 1850:813-23. [DOI: 10.1016/j.bbagen.2015.01.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 12/06/2014] [Accepted: 01/12/2015] [Indexed: 12/17/2022]
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Newby EA, Kaushal KM, Myers DA, Ducsay CA. Adrenocorticotropic Hormone and PI3K/Akt Inhibition Reduce eNOS Phosphorylation and Increase Cortisol Biosynthesis in Long-Term Hypoxic Ovine Fetal Adrenal Cortical Cells. Reprod Sci 2015; 22:932-41. [PMID: 25656500 DOI: 10.1177/1933719115570899] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study was designed to determine the role of the MEK/ERK1/2 and PI3K/Akt pathways in cortisol production and endothelial nitric oxide synthase (eNOS) phosphorylation (peNOS) in the ovine fetal adrenal in response to long-term hypoxia (LTH). Pregnant ewes were maintained at high altitude (3820 m) for the last 100 days of gestation (dGa). At 138 to 142 dGa, fetal adrenal cortical cells (FACs) were collected from LTH and age-matched normoxic fetuses. Cortisol production and peNOS were measured in response to pretreatment with the MEK/ERK1/2 pathway inhibitor UO126 (UO) and adrenocorticotropic hormone (ACTH) stimulation. UO126 reduced ACTH-stimulated cortisol in both normoxic and LTH FACs. UO126 alone or in combination with ACTH reduced peNOS in the normoxic group, while ACTH alone or ACTH + UO inhibited peNOS in LTH FACs. Additionally, cortisol was measured in response to pretreatment with UO and treatment with 22R-hydroxycholesterol (22R-OHC) or water-soluble cholesterol (WSC) with and without ACTH stimulation. UO126 had no effect on 22R-OHC-treated cells, but reduced cortisol in cells treated with WSC and/or ACTH. Cortisol and peNOS were also measured in response to pretreatment with PI3K/Akt pathway inhibitor Wortmannin (WT) and ACTH stimulation. Wortmannin further increased cortisol under ACTH-stimulated conditions and, like ACTH, reduced peNOS in LTH but not normoxic FACs. Together, these data suggest that in LTH FACs MEK/ERK1/2 does not regulate peNOS but that UO acts downstream from eNOS, possibly at cholesterol transport, to affect cortisol production in LTH FACs, while the PI3K/Akt pathway, along with ACTH, regulates peNOS and plays a role in the fetal adaptation to LTH in FACs.
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Affiliation(s)
- Elizabeth A Newby
- Center for Perinatal Biology, Loma Linda University, Loma Linda, CA, USA
| | - Kanchan M Kaushal
- Center for Perinatal Biology, Loma Linda University, Loma Linda, CA, USA
| | - Dean A Myers
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Charles A Ducsay
- Center for Perinatal Biology, Loma Linda University, Loma Linda, CA, USA
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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.
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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
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Wang Z, Zhang J, Li B, Gao X, Liu Y, Mao W, Chen SL. Resveratrol ameliorates low shear stress‑induced oxidative stress by suppressing ERK/eNOS‑Thr495 in endothelial cells. Mol Med Rep 2014; 10:1964-72. [PMID: 25198200 DOI: 10.3892/mmr.2014.2390] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Accepted: 05/09/2014] [Indexed: 11/06/2022] Open
Abstract
Fluid shear stress has been revealed to differentially regulate endothelial nitric oxide synthase (eNOS) distribution in vessels. eNOS, a key enzyme in controlling nitric oxide (NO) release, has a crucial role in mediating oxidative stress, and resveratrol (RSV)‑mediated eNOS also attenuates oxidative damage and suppresses endothelial dysfunction. To observe the protective effect of RSV on low shear stress (LSS)‑induced oxidative damage and the potential mechanisms involved, a parallel‑plate flow chamber, which imposed a low level of stress of 2 dynes/cm2 to cells, was employed. Reactive oxygen species (ROS), NO and apoptotic cells were examined in LSS‑treated endothelial cells (ECs) with or without RSV. Western blot analysis was used to examine LSS‑regulated eNOS‑Ser1177, Thr495 and Ser633, which were tightly associated with NO release. To further determine the underlying signaling pathways involved, extracellular signal‑regulated kinase (ERK), a possible upstream target of eNOS‑Thr495, was investigated, followed by examination of eNOS‑Thr495 in ERK‑inhibited cells. Additionally, eNOS mRNA expression levels were analyzed in cells challenged with LSS. The results revealed that RSV markedly decreased LSS‑induced oxidative damage in ECs. Furthermore, eNOS‑Ser1177 and Thr495 as well as phospho‑ERK were time‑dependently activated by LSS. The ERK inhibitor deactivated eNOS‑Thr495, which was accompanied by increased intracellular superoxide dismutase (SOD) levels. Of note, the activation effect of LSS on ERK/eNOS was markedly eliminated by RSV. In conclusion, RSV exerts antioxidant effects by suppressing LSS-activated ERK/eNOS and may provide a potential therapeutic target for atherosclerosis.
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Affiliation(s)
- Zhimei Wang
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Junxia Zhang
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Bing Li
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Xiaofei Gao
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Yanrong Liu
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Wenxing Mao
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
| | - Shao-Liang Chen
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu 210006, P.R. China
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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.
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Affiliation(s)
- Jayanth Ramadoss
- Department of Obstetrics and Gynaecology, University of Texas Medical Branch, Galveston, TX, USA
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Chao CY, Lii CK, Ye SY, Li CC, Lu CY, Lin AH, Liu KL, Chen HW. Docosahexaenoic acid inhibits vascular endothelial growth factor (VEGF)-induced cell migration via the GPR120/PP2A/ERK1/2/eNOS signaling pathway in human umbilical vein endothelial cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:4152-8. [PMID: 24734983 DOI: 10.1021/jf5007165] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Cell migration plays an important role in angiogenesis and wound repair. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen that is essential for endothelial cell survival, proliferation, and migration. Docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, shows both anti-inflammatory and antioxidant activities in vitro and in vivo. This study investigated the molecular mechanism by which DHA down-regulates VEGF-induced cell migration. HUVECs were used as the study model, and the MTT assay, Western blot, wound-healing assay, and phosphatase activity assay were used to explore the effects of DHA on cell migration. GPR120 is the putative receptor for DHA action. The results showed that DHA, PD98059 (an ERK1/2 inhibitor), and GW9508 (a GPR120 agonist) inhibited VEGF-induced cell migration. In contrast, pretreatment with okadaic acid (OA, a PP2A inhibitor) and S-nitroso-N-acetyl-DL-penicillamine (an NO donor) reversed the inhibition of cell migration by DHA. VEGF-induced cell migration was accompanied by phosphorylation of ERK1/2 and eNOS. Treatment of HUVECs with DHA increased PP2A enzyme activity and decreased VEGF-induced phosphorylation of ERK1/2 and eNOS. However, pretreatment with OA significantly decreased DHA-induced PP2A enzyme activity and reversed the DHA inhibition of VEGF-induced ERK1/2 and eNOS phosphorylation. These results suggest that stimulation of PP2A activity and inhibition of the VEGF-induced ERK1/2/eNOS signaling pathway may be involved in the DHA suppression of VEGF-induced cell migration. Thus, the effect of DHA on angiogenesis and wound repair is at least partly by virtue of its attenuation of cell migration.
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Affiliation(s)
- Che-Yi Chao
- Department of Health and Nutrition Biotechnology, Asia University , Taichung, Taiwan
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Xu G, Barrios-Rodiles M, Jerkic M, Turinsky AL, Nadon R, Vera S, Voulgaraki D, Wrana JL, Toporsian M, Letarte M. Novel protein interactions with endoglin and activin receptor-like kinase 1: potential role in vascular networks. Mol Cell Proteomics 2013; 13:489-502. [PMID: 24319055 DOI: 10.1074/mcp.m113.033464] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Endoglin and activin receptor-like kinase 1 are specialized transforming growth factor-beta (TGF-β) superfamily receptors, primarily expressed in endothelial cells. Mutations in the corresponding ENG or ACVRL1 genes lead to hereditary hemorrhagic telangiectasia (HHT1 and HHT2 respectively). To discover proteins interacting with endoglin, ACVRL1 and TGF-β receptor type 2 and involved in TGF-β signaling, we applied LUMIER, a high-throughput mammalian interactome mapping technology. Using stringent criteria, we identified 181 novel unique and shared interactions with ACVRL1, TGF-β receptor type 2, and endoglin, defining potential novel important vascular networks. In particular, the regulatory subunit B-beta of the protein phosphatase PP2A (PPP2R2B) interacted with all three receptors. Interestingly, the PPP2R2B gene lies in an interval in linkage disequilibrium with HHT3, for which the gene remains unidentified. We show that PPP2R2B protein interacts with the ACVRL1/TGFBR2/endoglin complex and recruits PP2A to nitric oxide synthase 3 (NOS3). Endoglin overexpression in endothelial cells inhibits the association of PPP2R2B with NOS3, whereas endoglin-deficient cells show enhanced PP2A-NOS3 interaction and lower levels of endogenous NOS3 Serine 1177 phosphorylation. Our data suggest that endoglin regulates NOS3 activation status by regulating PPP2R2B access to NOS3, and that PPP2R2B might be the HHT3 gene. Furthermore, endoglin and ACVRL1 contribute to several novel networks, including TGF-β dependent and independent ones, critical for vascular function and potentially defective in HHT.
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Affiliation(s)
- Guoxiong Xu
- Center Laboratory, Jinshan Hospital, Fudan University, Shanghai 201508, China
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ZHOU JIE, ABID MORADDIRHEMNAJI, XIONG YUFANG, CHEN QING, CHEN JUAN. ox-LDL downregulates eNOS activity via LOX-1-mediated endoplasmic reticulum stress. Int J Mol Med 2013; 32:1442-50. [DOI: 10.3892/ijmm.2013.1513] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 09/20/2013] [Indexed: 11/06/2022] Open
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Mineo C. Inhibition of nitric oxide and antiphospholipid antibody-mediated thrombosis. Curr Rheumatol Rep 2013; 15:324. [PMID: 23519891 DOI: 10.1007/s11926-013-0324-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The antiphospholipid syndrome (APS) is characterized by recurrent vascular thrombosis, thrombocytopenia, and fetal loss occurring in the presence of antiphospholipid antibodies (aPL). Along with arterial and venous thrombosis and pregnancy complications, patients with APS have an increased risk of myocardial infarction, stroke, and coronary artery disease, resulting from vascular cell dysfunction induced by aPL. Accumulating evidence to date indicates that interactions between circulating aPL and cell surface molecules of target cells, primarily endothelial cells and platelets, underlie the vascular disease phenotypes of APS. However, the molecular basis of APS is poorly understood. Nitric oxide produced by endothelial cells is a key determinant of vascular health that regulates several physiologic processes, including thrombosis, endothelial-leukocyte interaction, vascular cell migration, and the modulation of vascular tone. This review will discuss recent findings that indicate a novel mechanism by which aPL antagonize endothelial cell production of nitric oxide and thereby promote thrombosis.
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Affiliation(s)
- Chieko Mineo
- Department of Pediatrics, Division of Pulmonary and Vascular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9063, USA.
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AVE3085 protects coronary endothelium from the impairment of asymmetric dimethylarginine by activation and recoupling of eNOS. Cardiovasc Drugs Ther 2013; 26:383-92. [PMID: 22890813 DOI: 10.1007/s10557-012-6404-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of eNOS and it is recognized as a risk factor for endothelial dysfunction in cardiovascular diseases. We investigated the effect of AVE3085, a newly developed transcription enhancer of eNOS, on ADMA-induced endothelial dysfunction in coronary arteries with underlying mechanisms explored. METHODS Porcine coronary small arteries (diameter 600-800 μm) were studied in a myograph for endothelium-dependent relaxation to bradykinin and endothelium-independent relaxation to sodium nitroprusside. Protein expressions of eNOS and phosphorylated-eNOS (p-eNOS(Ser1177) and p-eNOS(Thr495)), and nitrotyrosine formation were determined by Western blot. NO release was directly measured with a NO microsensor. Productions of O(2) (.-) and peroxynitrite (ONOO(-)) were determined by lucigenin- and luminol- enhanced chemiluminescence respectively. RESULTS Exposure to ADMA significantly decreased the bradykinin-induced vasorelaxation and reduced the protein expression of p-eNOS(Ser1177) whereas increased the expression of p-eNOS(Thr495) and nitrotyrosine. Pre-incubation with AVE3085 restored the bradykinin-induced relaxation, reversed the decrease of p-eNOS(Ser1177), and lowered the level of p-eNOS(Thr495) and nitrotyrosine. NO release in response to bradykinin was significantly reduced by ADMA and such reduction was restored by AVE3085. AVE3085 also prevented the elevation of O (2) (.-) and ONOO(-) levels in coronary arteries exposed to ADMA. CONCLUSIONS AVE3085 prevents ADMA-induced endothelial dysfunction in coronary arteries. The protective effect of AVE3085 may be attributed to increased NO production resulting from enhanced eNOS activation, and decreased oxidative stress that involves inhibition of O (2) (.-) generation by eNOS recoupling. The present study suggested the therapeutic potential of AVE3085 in endothelial dysfunction in cardiovascular disorders.
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B56α subunit of protein phosphatase 2A mediates retinoic acid-induced decreases in phosphorylation of endothelial nitric oxide synthase at serine 1179 and nitric oxide production in bovine aortic endothelial cells. Biochem Biophys Res Commun 2013; 430:476-81. [DOI: 10.1016/j.bbrc.2012.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 12/04/2012] [Indexed: 11/22/2022]
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Niemann B, Pan R, Teschner M, Boening A, Silber RE, Rohrbach S. Age and obesity-associated changes in the expression and activation of components of the AMPK signaling pathway in human right atrial tissue. Exp Gerontol 2013; 48:55-63. [DOI: 10.1016/j.exger.2012.04.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 04/05/2012] [Accepted: 04/16/2012] [Indexed: 11/25/2022]
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Yang C, Talukder MAH, Varadharaj S, Velayutham M, Zweier JL. Early ischaemic preconditioning requires Akt- and PKA-mediated activation of eNOS via serine1176 phosphorylation. Cardiovasc Res 2012; 97:33-43. [PMID: 22977010 DOI: 10.1093/cvr/cvs287] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
AIMS The role of endothelial nitric oxide synthase (eNOS)/NO signalling is well documented in late ischaemic preconditioning (IPC); however, the role of eNOS and its activation in early IPC remains controversial. This study investigates the role of eNOS in early IPC and the signalling pathways and molecular interactions that regulate eNOS activation during early IPC. METHODS AND RESULTS Rat hearts were subjected to 30-min global ischaemia and reperfusion (I/R) with or without IPC (three cycles 5-min I and 5-min R) in the presence or absence of the NOS inhibitor l-NAME, phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (LY), and protein kinase A (PKA) inhibitor H89 during IPC induction or prior endothelial permeablization. IPC improved post-ischaemic contractile function and reduced infarction compared with I/R with this being abrogated by l-NAME or endothelial permeablization. eNOS(Ser1176), Akt(Ser473), and PKA(Thr197) phosphorylation was increased following IPC. I/R decreased eNOS(Ser1176) phosphorylation, whereas IPC increased it. Mass spectroscopy confirmed eNOS(Ser1176) phosphorylation and quantitative Western blots showed ∼24% modification of eNOS(Ser1176) following IPC. Immunoprecipitation demonstrated eNOS, Akt, and PKA complexation. Immunohistology showed IPC-induced Akt and PKA phosphorylation in cardiomyocytes and endothelium. With eNOS activation, IPC increased NO production as measured by electron paramagnetic resonance spin trapping and fluorescence microscopy. LY or H89 not only decreased Akt(Ser473) or PKA(Thr197) phosphorylation, respectively, but also abolished IPC-induced preservation of eNOS and eNOS(Ser1176) phosphorylation as well as cardioprotection. CONCLUSION Thus, Akt- and PKA-mediated eNOS activation, with phosphorylation near the C-terminus, is critical for early IPC-induced cardioprotection, with eNOS-derived NO from the endothelium serving a critical role.
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Affiliation(s)
- Changjun Yang
- Division of Cardiovascular Medicine, Department of Internal Medicine, Davis Heart and Lung Research Institute, The Ohio State University, 473 W. 12th Ave, Columbus, OH 43210, USA
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Zhang QJ, Holland WL, Wilson L, Tanner JM, Kearns D, Cahoon JM, Pettey D, Losee J, Duncan B, Gale D, Kowalski CA, Deeter N, Nichols A, Deesing M, Arrant C, Ruan T, Boehme C, McCamey DR, Rou J, Ambal K, Narra KK, Summers SA, Abel ED, Symons JD. Ceramide mediates vascular dysfunction in diet-induced obesity by PP2A-mediated dephosphorylation of the eNOS-Akt complex. Diabetes 2012; 61:1848-59. [PMID: 22586587 PMCID: PMC3379648 DOI: 10.2337/db11-1399] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Vascular dysfunction that accompanies obesity and insulin resistance may be mediated by lipid metabolites. We sought to determine if vascular ceramide leads to arterial dysfunction and to elucidate the underlying mechanisms. Pharmacological inhibition of de novo ceramide synthesis, using the Ser palmitoyl transferase inhibitor myriocin, and heterozygous deletion of dihydroceramide desaturase prevented vascular dysfunction and hypertension in mice after high-fat feeding. These findings were recapitulated in isolated arteries in vitro, confirming that ceramide impairs endothelium-dependent vasorelaxation in a tissue-autonomous manner. Studies in endothelial cells reveal that de novo ceramide biosynthesis induced protein phosphatase 2A (PP2A) association directly with the endothelial nitric oxide synthase (eNOS)/Akt/Hsp90 complex that was concurrent with decreased basal and agonist-stimulated eNOS phosphorylation. PP2A attenuates eNOS phosphorylation by preventing phosphorylation of the pool of Akt that colocalizes with eNOS and by dephosphorylating eNOS. Ceramide decreased the association between PP2A and the predominantly cytosolic inhibitor 2 of PP2A. We conclude that ceramide mediates obesity-related vascular dysfunction by a mechanism that involves PP2A-mediated disruption of the eNOS/Akt/Hsp90 signaling complex. These results provide important insight into a pathway that represents a novel target for reversing obesity-related vascular dysfunction.
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Affiliation(s)
- Quan-Jiang Zhang
- College of Health, University of Utah, Salt Lake City, Utah
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, Utah
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah
| | - William L. Holland
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Lloyd Wilson
- College of Health, University of Utah, Salt Lake City, Utah
| | | | - Devin Kearns
- College of Health, University of Utah, Salt Lake City, Utah
| | - Judd M. Cahoon
- College of Health, University of Utah, Salt Lake City, Utah
| | - Dix Pettey
- College of Health, University of Utah, Salt Lake City, Utah
| | - Jason Losee
- College of Health, University of Utah, Salt Lake City, Utah
| | - Bradlee Duncan
- College of Health, University of Utah, Salt Lake City, Utah
| | - Derrick Gale
- College of Health, University of Utah, Salt Lake City, Utah
| | | | | | | | | | - Colton Arrant
- College of Health, University of Utah, Salt Lake City, Utah
| | - Ting Ruan
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, Utah
| | - Christoph Boehme
- Department of Physics and Astronomy, College of Science, University of Utah, Salt Lake City, Utah
| | - Dane R. McCamey
- Department of Physics and Astronomy, College of Science, University of Utah, Salt Lake City, Utah
| | - Janvida Rou
- Department of Physics and Astronomy, College of Science, University of Utah, Salt Lake City, Utah
| | - Kapil Ambal
- Department of Physics and Astronomy, College of Science, University of Utah, Salt Lake City, Utah
| | - Krishna K. Narra
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, Utah
| | - Scott A. Summers
- Program in Cardiovascular and Metabolic Diseases, Duke-NUS Graduate Medical School, Singapore, and the Stedman Center for Nutrition and Metabolism Research, Duke University Medical Center, Durham, North Carolina
| | - E. Dale Abel
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, Utah
- Program in Molecular Medicine, University of Utah, Salt Lake City, Utah
- Corresponding authors: E. Dale Abel, , and J. David Symons,
| | - J. David Symons
- College of Health, University of Utah, Salt Lake City, Utah
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, Utah
- Corresponding authors: E. Dale Abel, , and J. David Symons,
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Abstract
During normal pregnancy, dramatically increased placental blood flow is critical for fetal growth and survival as well as neonatal birth weights and survivability. This increased blood flow results from angiogenesis, vasodilatation, and vascular remodeling. Locally produced growth factors including fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) are key regulators of placental endothelial functions including cell proliferation, migration, and vasodilatation. However, the precise signaling mechanisms underlying such regulation in fetoplacental endothelium are less well defined, specifically with regard to the interactions amongst protein kinases (PKs), protein phosphatase, and nitric oxide (NO). Recently, we and other researchers have obtained solid evidence showing that different signaling mechanisms participate in FGF2- and VEGFA-regulated fetoplacental endothelial cell proliferation and migration as well as NO production. This review will briefly summarize currently available data on signaling mediating fetoplacental angiogenesis with a specific emphasis on PKs, ERK1/2, AKT1, and p38 MAPK and protein phosphatases, PPP2 and PPP3.
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Affiliation(s)
- Kai Wang
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 200040, China
| | - Jing Zheng
- Department of Obstetrics and Gynecology, University of Wisconsin, Madison, WI 53715
- Address correspondence and reprint requests to: Jing Zheng, Ph.D., Departments of Obstetrics and Gynecology, Perinatal Research Laboratories, University of Wisconsin, PAB1 Meriter Hospital, 202 S Park St., Madison, WI 53715. Phone: (608) 417-6314 Fax: (608) 257-1304.
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McMurry JL, Chrestensen CA, Scott IM, Lee EW, Rahn AM, Johansen AM, Forsberg BJ, Harris KD, Salerno JC. Rate, affinity and calcium dependence of nitric oxide synthase isoform binding to the primary physiological regulator calmodulin. FEBS J 2011; 278:4943-54. [PMID: 22004458 DOI: 10.1111/j.1742-4658.2011.08395.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using interferometry-based biosensors the binding and release of endothelial and neuronal nitric oxide synthase (eNOS and nNOS) from calmodulin (CaM) was measured. In both isoforms, binding to CaM is diffusion limited and within approximately three orders of magnitude of the Smoluchowski limit imposed by orientation-independent collisions. This suggests that the orientation of CaM is facilitated by the charge arrays on the CaM-binding site and the complementary surface on CaM. Protein kinase C phosphorylation of eNOS T495, adjacent to the CaM-binding site, abolishes or greatly slows CaM binding. Kinases which increase the activity of eNOS did not stimulate the binding of CaM, which is already diffusion limited. The coupling of Ca(2+) binding and CaM/NOS binding equilibria links the affinity of CaM for NOS to the Ca(2+) dependence of CaM binding. Hence, changes in the Ca(2+) sensitivity of CaM binding always imply changes in the NOS-CaM affinity. It is possible, however, that in some regimes binding and activation are not synonymous, so that Ca(2+) sensitivity need not be tightly linked to CaM sensitivity of activation. This study is being extended using mutants to probe the roles of individual structural elements in binding and release.
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Affiliation(s)
- Jonathan L McMurry
- Department of Chemistry & Biochemistry, Kennesaw State University, Kennesaw, GA 30144, USA
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Sharma V, McNeill JH. Parallel effects of β-adrenoceptor blockade on cardiac function and fatty acid oxidation in the diabetic heart: Confronting the maze. World J Cardiol 2011; 3:281-302. [PMID: 21949571 PMCID: PMC3176897 DOI: 10.4330/wjc.v3.i9.281] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 07/18/2011] [Accepted: 07/25/2011] [Indexed: 02/06/2023] Open
Abstract
Diabetic cardiomyopathy is a disease process in which diabetes produces a direct and continuous myocardial insult even in the absence of ischemic, hypertensive or valvular disease. The β-blocking agents bisoprolol, carvedilol and metoprolol have been shown in large-scale randomized controlled trials to reduce heart failure mortality. In this review, we summarize the results of our studies investigating the effects of β-blocking agents on cardiac function and metabolism in diabetic heart failure, and the complex inter-related mechanisms involved. Metoprolol inhibits fatty acid oxidation at the mitochondrial level but does not prevent lipotoxicity; its beneficial effects are more likely to be due to pro-survival effects of chronic treatment. These studies have expanded our understanding of the range of effects produced by β-adrenergic blockade and show how interconnected the signaling pathways of function and metabolism are in the heart. Although our initial hypothesis that inhibition of fatty acid oxidation would be a key mechanism of action was disproved, unexpected results led us to some intriguing regulatory mechanisms of cardiac metabolism. The first was upstream stimulatory factor-2-mediated repression of transcriptional master regulator PGC-1α, most likely occurring as a consequence of the improved function; it is unclear whether this effect is unique to β-blockers, although repression of carnitine palmitoyltransferase (CPT)-1 has not been reported with other drugs which improve function. The second was the identification of a range of covalent modifications which can regulate CPT-1 directly, mediated by a signalome at the level of the mitochondria. We also identified an important interaction between β-adrenergic signaling and caveolins, which may be a key mechanism of action of β-adrenergic blockade. Our experience with this labyrinthine signaling web illustrates that initial hypotheses and anticipated directions do not have to be right in order to open up meaningful directions or reveal new information.
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Affiliation(s)
- Vijay Sharma
- Vijay Sharma, John H McNeill, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z3.F, Canada
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Rafikov R, Fonseca FV, Kumar S, Pardo D, Darragh C, Elms S, Fulton D, Black SM. eNOS activation and NO function: structural motifs responsible for the posttranslational control of endothelial nitric oxide synthase activity. J Endocrinol 2011; 210:271-84. [PMID: 21642378 PMCID: PMC3326601 DOI: 10.1530/joe-11-0083] [Citation(s) in RCA: 167] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rather than being a constitutive enzyme as was first suggested, endothelial nitric oxide synthase (eNOS) is dynamically regulated at the transcriptional, posttranscriptional, and posttranslational levels. This review will focus on how changes in eNOS function are conferred by various posttranslational modifications. The latest knowledge regarding eNOS targeting to the plasma membrane will be discussed as the role of protein phosphorylation as a modulator of catalytic activity. Furthermore, new data are presented that provide novel insights into how disruption of the eNOS dimer prevents eNOS uncoupling and the production of superoxide under conditions of elevated oxidative stress and identifies a novel regulatory region we have termed the 'flexible arm'.
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Affiliation(s)
- Ruslan Rafikov
- Pulmonary Vascular Disease Program, Vascular Biology Center: CB-3211B, Georgia Health Sciences University, 1459 Laney Walker Boulevard, Augusta, GA 30912, USA
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Mineo C, Shaul PW. New Insights into the Molecular Basis of the Antiphospholipid Syndrome. ACTA ACUST UNITED AC 2011; 8:e47-e52. [PMID: 22773925 DOI: 10.1016/j.ddmec.2011.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Antiphospholipid syndrome is an autoimmune disease characterized by the presence of circulating antiphospholipid antibodies (aPL) that promote thrombosis, pregnancy complications and cardiovascular diseases. Alterations in the function of vascular cells induced by aPL underlie these outcomes. This review will discuss recent findings that indicate a novel mechanism by which aPL antagonize endothelial cell production of nitric oxide and thereby promote thrombosis.
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Affiliation(s)
- Chieko Mineo
- Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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Wu Q, Chambliss K, Umetani M, Mineo C, Shaul PW. Non-nuclear estrogen receptor signaling in the endothelium. J Biol Chem 2011; 286:14737-43. [PMID: 21343284 PMCID: PMC3083154 DOI: 10.1074/jbc.r110.191791] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
In addition to the classical function of estrogen receptors (ER) as transcription factors, evidence continues to accumulate that they mediate non-nuclear processes in numerous cell types, including the endothelium, in which they activate endothelial NO synthase. Non-nuclear ER signaling entails unique post-translational modifications and protein-protein interactions of the receptor with adaptor molecules, kinases, and G proteins. Recent in vitro and in vivo studies in mice using an estrogen-dendrimer conjugate that is excluded from the nucleus indicate that non-nuclear ER activation underlies the migration and growth responses of endothelial cells to estrogen but not the growth responses of endometrial or breast cancer cells to the hormone. In this minireview, the features of ERα and protein-protein interactions that enable it to invoke extranuclear signaling in the endothelium and the consequences of that signaling are discussed.
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Affiliation(s)
- Qian Wu
- From the Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Ken Chambliss
- From the Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Michihisa Umetani
- From the Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Chieko Mineo
- From the Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Philip W. Shaul
- From the Division of Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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50
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Teng R, Calvert JW, Sibmooh N, Piknova B, Suzuki N, Sun J, Martinez K, Yamamoto M, Schechter AN, Lefer DJ, Noguchi CT. Acute erythropoietin cardioprotection is mediated by endothelial response. Basic Res Cardiol 2011; 106:343-54. [PMID: 21347618 DOI: 10.1007/s00395-011-0158-z] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 01/25/2011] [Accepted: 01/25/2011] [Indexed: 11/30/2022]
Abstract
Increasing evidence indicates that high levels of serum erythropoietin (Epo) can lessen ischemia-reperfusion injury in the heart and multiple cardiac cell types have been suggested to play a role in this Epo effect. To clarify the mechanisms underlying this cardioprotection, we explored Epo treatment of coronary artery endothelial cells and Epo cardioprotection in a Mus musculus model with Epo receptor expression restricted to hematopoietic and endothelial cells (ΔEpoR). Epo stimulation of coronary artery endothelial cells upregulated endothelial nitric oxide synthase (eNOS) activity in vitro and in vivo, and enhanced nitric oxide (NO) production that was determined directly by real-time measurements of gaseous NO release. Epo stimulated phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase kinase (MEK)/extracellular signal regulated kinase (ERK) signaling pathways, and inhibition of PI3K, but not MEK activity, blocked Epo-induced NO production. To verify the potential of this Epo effect in cardioprotection in vivo, ΔEpoR-mice with Epo response in heart restricted to endothelium were treated with Epo. These mice exhibited a similar increase in eNOS phosphorylation in coronary artery endothelium as that found in wild type (WT) mice. In addition, in both WT- and ΔEpoR-mice, exogenous Epo treatment prior to myocardial ischemia provided comparable protection. These data provide the first evidence that endothelial cell response to Epo is sufficient to achieve an acute cardioprotective effect. The immediate response of coronary artery endothelial cells to Epo stimulation by NO production may be a critical mechanism underlying this Epo cardioprotection.
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Affiliation(s)
- Ruifeng Teng
- Molecular Medicine Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-1822, USA
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