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Tamargo IA, Baek KI, Kim Y, Park C, Jo H. Flow-induced reprogramming of endothelial cells in atherosclerosis. Nat Rev Cardiol 2023; 20:738-753. [PMID: 37225873 PMCID: PMC10206587 DOI: 10.1038/s41569-023-00883-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/25/2023] [Indexed: 05/26/2023]
Abstract
Atherosclerotic diseases such as myocardial infarction, ischaemic stroke and peripheral artery disease continue to be leading causes of death worldwide despite the success of treatments with cholesterol-lowering drugs and drug-eluting stents, raising the need to identify additional therapeutic targets. Interestingly, atherosclerosis preferentially develops in curved and branching arterial regions, where endothelial cells are exposed to disturbed blood flow with characteristic low-magnitude oscillatory shear stress. By contrast, straight arterial regions exposed to stable flow, which is associated with high-magnitude, unidirectional shear stress, are relatively well protected from the disease through shear-dependent, atheroprotective endothelial cell responses. Flow potently regulates structural, functional, transcriptomic, epigenomic and metabolic changes in endothelial cells through mechanosensors and mechanosignal transduction pathways. A study using single-cell RNA sequencing and chromatin accessibility analysis in a mouse model of flow-induced atherosclerosis demonstrated that disturbed flow reprogrammes arterial endothelial cells in situ from healthy phenotypes to diseased ones characterized by endothelial inflammation, endothelial-to-mesenchymal transition, endothelial-to-immune cell-like transition and metabolic changes. In this Review, we discuss this emerging concept of disturbed-flow-induced reprogramming of endothelial cells (FIRE) as a potential pro-atherogenic mechanism. Defining the flow-induced mechanisms through which endothelial cells are reprogrammed to promote atherosclerosis is a crucial area of research that could lead to the identification of novel therapeutic targets to combat the high prevalence of atherosclerotic disease.
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Affiliation(s)
- Ian A Tamargo
- Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
- Molecular and Systems Pharmacology Program, Emory University, Atlanta, GA, USA
| | - Kyung In Baek
- Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Yerin Kim
- Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Christian Park
- Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Hanjoong Jo
- Wallace H. Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA.
- Molecular and Systems Pharmacology Program, Emory University, Atlanta, GA, USA.
- Department of Medicine, Emory University School, Atlanta, GA, USA.
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2
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Gola L, Bierhansl L, Csatári J, Schroeter CB, Korn L, Narayanan V, Cerina M, Abdolahi S, Speicher A, Hermann AM, König S, Dinkova-Kostova AT, Shekh-Ahmad T, Meuth SG, Wiendl H, Gorji A, Pawlowski M, Kovac S. NOX4-derived ROS are neuroprotective by balancing intracellular calcium stores. Cell Mol Life Sci 2023; 80:127. [PMID: 37081190 PMCID: PMC10119225 DOI: 10.1007/s00018-023-04758-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 03/06/2023] [Accepted: 03/14/2023] [Indexed: 04/22/2023]
Abstract
Hyperexcitability is associated with neuronal dysfunction, cellular death, and consequently neurodegeneration. Redox disbalance can contribute to hyperexcitation and increased reactive oxygen species (ROS) levels are observed in various neurological diseases. NOX4 is an NADPH oxidase known to produce ROS and might have a regulating function during oxidative stress. We, therefore, aimed to determine the role of NOX4 on neuronal firing, hyperexcitability, and hyperexcitability-induced changes in neural network function. Using a multidimensional approach of an in vivo model of hyperexcitability, proteomic analysis, and cellular function analysis of ROS, mitochondrial integrity, and calcium levels, we demonstrate that NOX4 is neuroprotective by regulating ROS and calcium homeostasis and thereby preventing hyperexcitability and consequently neuronal death. These results implicate NOX4 as a potential redox regulator that is beneficial in hyperexcitability and thereby might have an important role in neurodegeneration.
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Affiliation(s)
- Lukas Gola
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Laura Bierhansl
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Júlia Csatári
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Christina B Schroeter
- Department of Neurology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Lisanne Korn
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Venu Narayanan
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Manuela Cerina
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Sara Abdolahi
- Shefa Neuroscience Research Center, Khatam Alanbia Hospital, Tehran, Iran
| | - Anna Speicher
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Alexander M Hermann
- Department of Neurology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Simone König
- Core Unit Proteomics, Interdisciplinary Center for Clinical Research, Medical Faculty, University of Münster, 48149, Münster, Germany
| | | | - Tawfeeq Shekh-Ahmad
- Institute for Drug Research, The School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Jerusalem, Israel
| | - Sven G Meuth
- Department of Neurology, Medical Faculty, Heinrich Heine University Düsseldorf, 40225, Düsseldorf, Germany
| | - Heinz Wiendl
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Ali Gorji
- Shefa Neuroscience Research Center, Khatam Alanbia Hospital, Tehran, Iran
- Epilepsy Research Center, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Matthias Pawlowski
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany
| | - Stjepana Kovac
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, 48149, Münster, Germany.
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3
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Tolkmitt J, Brendel H, Zatschler B, Brose S, Brunssen C, Kopaliani I, Deussen A, Matschke K, Morawietz H. Aprotinin does not Impair Vascular Function in Patients Undergoing Coronary Artery Bypass Graft Surgery. Horm Metab Res 2023; 55:65-74. [PMID: 36599358 DOI: 10.1055/a-1984-0255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bleeding is a major complication in coronary artery bypass graft surgery. Antifibrinolytic agents like serine protease inhibitor aprotinin can decrease postoperative bleeding and complications of cardiac surgery. However, the effects of aprotinin on vascular function are not completely elucidated. We compared the ex vivo vascular function of left internal mammary arteries from patients undergoing coronary artery bypass graft surgery with and without intraoperative application of aprotinin using a Mulvany Myograph. Human internal mammary arteries were treated with aprotinin ex vivo and tested for changes in vascular function. We analyzed the impact of aprotinin on vascular function in rat aortic rings. Finally, impact of aprotinin on expression and activity of endothelial nitric oxide synthase was tested in human endothelial cells. Intraoperative application of aprotinin did not impair ex vivo vascular function of internal mammary arteries of patients undergoing coronary artery bypass graft surgery. Endothelium-dependent and -independent relaxations were not different in patients with or without aprotinin after nitric oxide synthase blockade. A maximum vasorelaxation of 94.5%±11.4vs. 96.1%±5.5% indicated a similar vascular smooth muscle function in both patient groups (n=13 each). Long-term application of aprotinin under physiological condition preserved vascular function of the rat aorta. In vitro application of increasing concentrations of aprotinin on human endothelial cells resulted in a similar expression and activity of endothelial nitric oxide synthase. In conclusion, intraoperative and ex vivo application of aprotinin does not impair the endothelial function in human internal mammary arteries and experimental models.
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Affiliation(s)
- Josephine Tolkmitt
- Department of Medicine III, Division of Vascular Endothelium and Microcirculation, Technische Universität Dresden, Dresden, Germany
| | - Heike Brendel
- Department of Medicine III, Division of Vascular Endothelium and Microcirculation, Technische Universität Dresden, Dresden, Germany
| | - Birgit Zatschler
- Institute of Physiology, Technische Universität Dresden, Dresden, Germany
| | - Stefan Brose
- Department of Cardiac Surgery, University Heart Center Dresden, Technische Universität Dresden, Dresden, Germany
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Technische Universität Dresden, Dresden, Germany
| | - Irakli Kopaliani
- Institute of Physiology, Technische Universität Dresden, Dresden, Germany
| | - Andreas Deussen
- Institute of Physiology, Technische Universität Dresden, Dresden, Germany
| | - Klaus Matschke
- Department of Cardiac Surgery, University Heart Center Dresden, Technische Universität Dresden, Dresden, Germany
| | - Henning Morawietz
- Department of Medicine III, Division of Vascular Endothelium and Microcirculation, Technische Universität Dresden, Dresden, Germany
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4
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Emami MH, Sereshki N, Malakoutikhah Z, Dehkordi SAE, Fahim A, Mohammadzadeh S, Maghool F. Nrf2 signaling pathway in trace metal carcinogenesis: A cross-talk between oxidative stress and angiogenesis. Comp Biochem Physiol C Toxicol Pharmacol 2022; 254:109266. [PMID: 35031482 DOI: 10.1016/j.cbpc.2022.109266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/31/2021] [Accepted: 01/05/2022] [Indexed: 12/15/2022]
Abstract
A large number of people worldwide are affected by chronic metal exposure, which is known to be associated with different type of malignancies. The mechanisms of metal carcinogenicity are complex in nature, and excessive reactive oxygen species (ROS) generation induced by chronic metal exposure, among the other factors, has been proposed as one of the major mechanisms involved in that process. In tumor cells, ROS buildup may lead to cell death through intrinsic and extrinsic signaling pathways. Furthermore, ROS-mediated redox signaling has a crucial role in angiogenesis, which is recognized as an essential step in tumor progression. There are several redox-modulating pathways and among them, the nuclear factor erythroid2-related factor2 (Nrf2), as a sensor of oxidative or electrophilic stress, has introduced as a master regulator of cellular response against environmental stresses. Activation of Nrf2 signaling induces expression of wide variety of antioxidant and detoxification enzymes genes. Thus, this transcription factor has recently received much attention as a target for cancer chemoprevention. But meanwhile, constitutive Nrf2 activation in cancerous cells may promote cancer progression and resistance to chemotherapy. The current review describes the major underlying mechanisms involved in carcinogenesis of trace metals: copper, silver, and cadmium, with a special focus on the Nrf2 signaling pathway as a crossroad between oxidative stress and angiogenesis.
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Affiliation(s)
- Mohammad Hassan Emami
- Poursina Hakim Digestive Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nasrin Sereshki
- Poursina Hakim Digestive Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Zahra Malakoutikhah
- Applied Physiology Research Center, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Alireza Fahim
- Poursina Hakim Digestive Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Samane Mohammadzadeh
- Poursina Hakim Digestive Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Fatemeh Maghool
- Poursina Hakim Digestive Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
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5
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Sharmin R, Hamoh T, Sigaeva A, Mzyk A, Damle VG, Morita A, Vedelaar T, Schirhagl R. Fluorescent Nanodiamonds for Detecting Free-Radical Generation in Real Time during Shear Stress in Human Umbilical Vein Endothelial Cells. ACS Sens 2021; 6:4349-4359. [PMID: 34797983 DOI: 10.1021/acssensors.1c01582] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Free-radical generation is suspected to play a key role in cardiovascular diseases. Another crucial factor is shear stress. Human umbilical vein endothelial cells (HUVECS), which form the lining of blood vessels, require a physiological shear stress to activate many vasoactive factors. These are needed for maintaining vascular cell functions such as nonthrombogenicity, regulation of blood flow, and vascular tone. Additionally, blood clots form at regions of high shear stress within a blood vessel. Here, we use a new method called diamond magnetometry which allows us to measure the dynamics of free-radical generation in real time under shear stress. This quantum sensing technique allows free-radical detection with nanoscale resolution at the single-cell level. We investigate radical formation in HUVECs in a microfluidic environment under different flow conditions typically found in veins and arteries. Here, we looked into free-radical formation before, during, and after flow. We found that the free-radical production varied depending on the flow conditions. To confirm the magnetometry results and to differentiate between radicals, we performed conventional fluorescent reactive oxygen species (ROS) assays specific for superoxide, nitric oxide, and overall ROS.
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Affiliation(s)
- Rokshana Sharmin
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
| | - Thamir Hamoh
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
| | - Alina Sigaeva
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
| | - Aldona Mzyk
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
- Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Reymonta 25, 30-059 Krakow, Poland
| | - Viraj G. Damle
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
| | - Aryan Morita
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
- Department of Dental Biomedical Sciences, Faculty of Dentistry, Universitas Gadjah Mada, Jalan Denta 1 Sekip Utara, 55281 Yogyakarta, Indonesia
| | - Thea Vedelaar
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
| | - Romana Schirhagl
- Department Biomedical Engineering, Groningen University, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AW Groningen, The Netherlands
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6
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Giebe S, Hofmann A, Brux M, Lowe F, Breheny D, Morawietz H, Brunssen C. Comparative study of the effects of cigarette smoke versus next generation tobacco and nicotine product extracts on endothelial function. Redox Biol 2021; 47:102150. [PMID: 34601427 PMCID: PMC8531844 DOI: 10.1016/j.redox.2021.102150] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/23/2021] [Accepted: 09/24/2021] [Indexed: 11/29/2022] Open
Abstract
Tobacco smoking and hemodynamic forces are key stimuli for the development of endothelial dysfunction. As an alternative to smoking, next generation tobacco and nicotine products (NGP) are now widely used. However, little is known about their potential pro-inflammatory and atherogenic effects on the endothelium. In this study, we analyzed key parameters of endothelial function after exposure to aqueous smoke extracts (AqE) of a heated tobacco product (HTP), an electronic cigarette (e-cig), a conventional cigarette (3R4F) and pure nicotine. All experiments were performed under atheroprotective high laminar or atherogenic low flow with primary human endothelial cells. Treatment with 3R4F, but not alternative smoking products, reduced endothelial cell viability and wound healing capability via the PI3K/AKT/eNOS(NOS3) pathway. Laminar flow delayed detrimental effects on cell viability by 3R4F treatment. 3R4F stimulation led to activation of NRF2 antioxidant defense system at nicotine concentrations ≥0.56 μg/ml and increased expression of its target genes HMOX1 and NQO1. Treatment with HTP revealed an induction of HMOX1 and NQO1 at dosages with ≥1.68 μg/ml nicotine, whereas e-cig and nicotine exposure had no impact. Analyses of pro-inflammatory genes revealed an increased ICAM1 expression under 3R4F treatment. 3R4F reduced VCAM1 expression in a dose-dependent manner; HTP treatment had similar but milder effects; e-cig and nicotine treatment had no impact. SELE expression was induced by 3R4F under static conditions. High laminar flow prevented this upregulation. Stimulation with laminar flow led to downregulation of CCL2 (MCP-1). From this downregulated level, only 3R4F increased CCL2 expression at higher concentrations. Finally, under static conditions, all components increased adhesion of monocytes to endothelial cells. Interestingly, only stimulation with 3R4F revealed increased monocyte adhesion under atherosclerosis-prone low flow. In conclusion, all product categories activated anti-oxidative or pro-inflammatory patterns. NGP responses were typically lower than in 3R4F exposed cells. Also, 3R4F stimulation led to an impaired endothelial wound healing and induced a pro-inflammatory phenotype compared to NGP treatment.
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Affiliation(s)
- Sindy Giebe
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Anja Hofmann
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Melanie Brux
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Frazer Lowe
- Group Research & Development, British American Tobacco, Southampton, United Kingdom
| | - Damien Breheny
- Group Research & Development, British American Tobacco, Southampton, United Kingdom
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany.
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7
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Taylor JP, Tse HM. The role of NADPH oxidases in infectious and inflammatory diseases. Redox Biol 2021; 48:102159. [PMID: 34627721 PMCID: PMC8487856 DOI: 10.1016/j.redox.2021.102159] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 02/06/2023] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOX) are enzymes that generate superoxide or hydrogen peroxide from molecular oxygen utilizing NADPH as an electron donor. There are seven enzymes in the NOX family: NOX1-5 and dual oxidase (DUOX) 1-2. NOX enzymes in humans play important roles in diverse biological functions and vary in expression from tissue to tissue. Importantly, NOX2 is involved in regulating many aspects of innate and adaptive immunity, including regulation of type I interferons, the inflammasome, phagocytosis, antigen processing and presentation, and cell signaling. DUOX1 and DUOX2 play important roles in innate immune defenses at epithelial barriers. This review discusses the role of NOX enzymes in normal physiological processes as well as in disease. NOX enzymes are important in autoimmune diseases like type 1 diabetes and have also been implicated in acute lung injury caused by infection with SARS-CoV-2. Targeting NOX enzymes directly or through scavenging free radicals may be useful therapies for autoimmunity and acute lung injury where oxidative stress contributes to pathology.
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Affiliation(s)
- Jared P Taylor
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hubert M Tse
- Department of Microbiology, Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, USA.
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8
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Buchmann GK, Schürmann C, Spaeth M, Abplanalp W, Tombor L, John D, Warwick T, Rezende F, Weigert A, Shah AM, Hansmann ML, Weissmann N, Dimmeler S, Schröder K, Brandes RP. The hydrogen-peroxide producing NADPH oxidase 4 does not limit neointima development after vascular injury in mice. Redox Biol 2021; 45:102050. [PMID: 34218201 PMCID: PMC8256285 DOI: 10.1016/j.redox.2021.102050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/15/2021] [Accepted: 06/15/2021] [Indexed: 11/26/2022] Open
Abstract
Objective The NADPH oxidase Nox4 is an important source of H2O2. Nox4-derived H2O2 limits vascular inflammation and promotes smooth muscle differentiation. On this basis, the role of Nox4 for restenosis development was determined in the mouse carotid artery injury model. Methods and results Genetic deletion of Nox4 by a tamoxifen-activated Cre-Lox-system did not impact on neointima formation in the carotid artery wire injury model. To understand this unexpected finding, time-resolved single-cell RNA-sequencing (scRNAseq) from injured carotid arteries of control mice and massive-analysis-of-cDNA-ends (MACE)-RNAseq from the neointima harvested by laser capture microdissection of control and Nox4 knockout mice was performed. This revealed that resting smooth muscle cells (SMCs) and fibroblasts exhibit high Nox4 expression, but that the proliferating de-differentiated SMCs, which give rise to the neointima, have low Nox4 expression. In line with this, the first weeks after injury, gene expression was unchanged between the carotid artery neointimas of control and Nox4 knockout mice. Conclusion Upon vascular injury, Nox4 expression is transiently lost in the cells which comprise the neointima. NADPH oxidase 4 therefore does not interfere with restenosis development after wire-induced vascular injury.
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Affiliation(s)
- Giulia K Buchmann
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Christoph Schürmann
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Manuela Spaeth
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Wesley Abplanalp
- German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany; Institute of Cardiovascular Regeneration, Centre for Molecular Medicine, Goethe University Frankfurt, Germany
| | - Lukas Tombor
- German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany; Institute of Cardiovascular Regeneration, Centre for Molecular Medicine, Goethe University Frankfurt, Germany
| | - David John
- German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany; Institute of Cardiovascular Regeneration, Centre for Molecular Medicine, Goethe University Frankfurt, Germany
| | - Timothy Warwick
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Flávia Rezende
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Andreas Weigert
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ajay M Shah
- School of Cardiovascular Medicine & Sciences, King's College London, British Heart Foundation Centre, London, UK
| | | | - Norbert Weissmann
- Excellence Cluster Cardio-Pulmonary Institute (CPI), Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Gießen, Germany
| | - Stefanie Dimmeler
- German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany; Institute of Cardiovascular Regeneration, Centre for Molecular Medicine, Goethe University Frankfurt, Germany
| | - Katrin Schröder
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany
| | - Ralf P Brandes
- Institute for Cardiovascular Physiology, Goethe-University, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Frankfurt Am Main, Germany.
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9
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TBHQ-Overview of Multiple Mechanisms against Oxidative Stress for Attenuating Methamphetamine-Induced Neurotoxicity. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:8874304. [PMID: 33354283 PMCID: PMC7735854 DOI: 10.1155/2020/8874304] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 12/13/2022]
Abstract
Methamphetamine is a derivative of amphetamines, a highly addictive central stimulant with multiple systemic toxicity including the brain, heart, liver, lung, and spleen. It has adverse effects such as apoptosis and breakdown of the blood-brain barrier. Methamphetamine is a fatal and toxic chemical substance, and its lethal mechanism has been widely studied in recent years. The possible mechanism is that methamphetamine can cause cardiotoxicity and neurotoxicity mainly by inducing oxidative stress so as to generate heat, eliminate people's hunger and thirst, and maintain a state of excitement so that people can continue to exercise. According to many research, there is no doubt that methamphetamine triggers neurotoxicity by inducing reactive oxygen species (ROS) production and redox imbalance. This review summarized the mechanisms of methamphetamine-induced neurotoxicity including apoptosis and blood-brain barrier breakdown through oxidative stress and analyzed several possible antioxidative mechanisms of tert-butylhydroquinone (TBHQ) which is a kind of food additive with antioxidative effects. As a nuclear factor E2-related factor 2 (Nrf2) agonist, TBHQ may inhibit neurotoxicity caused by oxidative stress through the following three mechanisms: the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system, the astrocytes activation, and the glutathione pathway. The mechanism about methamphetamine's toxic effects and its antioxidative therapeutic drugs would become a research hotspot in this field and has very important research significance.
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10
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Brendel H, Shahid A, Hofmann A, Mittag J, Bornstein SR, Morawietz H, Brunssen C. NADPH oxidase 4 mediates the protective effects of physical activity against obesity-induced vascular dysfunction. Cardiovasc Res 2019; 116:1767-1778. [DOI: 10.1093/cvr/cvz322] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 08/13/2019] [Accepted: 12/02/2019] [Indexed: 11/13/2022] Open
Abstract
Abstract
Aims
Physical activity is one of the most potent strategies to prevent endothelial dysfunction. Recent evidence suggests vaso-protective properties of hydrogen peroxide (H2O2) produced by main endothelial NADPH oxidase isoform 4 (Nox4) in the vasculature. Therefore, we hypothesized that Nox4 connects physical activity with vaso-protective effects.
Methods and results
Analysis of the endothelial function using Mulvany Myograph showed endothelial dysfunction in wild-type (WT) as well as in C57BL/6J/ Nox4−/− (Nox4−/−) mice after 20 weeks on high-fat diet (HFD). Access to running wheels during the HFD prevented endothelial dysfunction in WT but not in Nox4−/− mice. Mechanistically, exercise led to an increased H2O2 release in the aorta of WT mice with increased phosphorylation of eNOS pathway member AKT serine/threonine kinase 1 (AKT1). Both H2O2 release and phosphorylation of AKT1 were diminished in aortas of Nox4−/− mice. Deletion of Nox4 also resulted in lower intracellular calcium release proven by reduced phenylephrine-mediated contraction, whilst potassium-induced contraction was not affected. H2O2 scavenger catalase reduced phenylephrine-induced contraction in WT mice. Supplementing H2O2 increased phenylephrine-induced contraction in Nox4−/− mice. Exercise-induced peroxisome proliferative-activated receptor gamma, coactivator 1 alpha (Ppargc1a), as key regulator of mitochondria biogenesis in WT but not Nox4−/− mice. Furthermore, exercise-induced citrate synthase activity and mitochondria mass were reduced in the absence of Nox4. Thus, Nox4−/− mice became less active and ran less compared with WT mice.
Conclusions
Nox4 derived H2O2 plays a key role in exercise-induced adaptations of eNOS and Ppargc1a pathway and intracellular calcium release. Hence, loss of Nox4 diminished physical activity performance and vascular protective effects of exercise.
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Affiliation(s)
- Heike Brendel
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Amna Shahid
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Anja Hofmann
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Jennifer Mittag
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Stefan R Bornstein
- Department of Medicine III, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus, University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
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11
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Zemskov EA, Lu Q, Ornatowski W, Klinger CN, Desai AA, Maltepe E, Yuan JXJ, Wang T, Fineman JR, Black SM. Biomechanical Forces and Oxidative Stress: Implications for Pulmonary Vascular Disease. Antioxid Redox Signal 2019; 31:819-842. [PMID: 30623676 PMCID: PMC6751394 DOI: 10.1089/ars.2018.7720] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Significance: Oxidative stress in the cell is characterized by excessive generation of reactive oxygen species (ROS). Superoxide (O2-) and hydrogen peroxide (H2O2) are the main ROS involved in the regulation of cellular metabolism. As our fundamental understanding of the underlying causes of lung disease has increased it has become evident that oxidative stress plays a critical role. Recent Advances: A number of cells in the lung both produce, and respond to, ROS. These include vascular endothelial and smooth muscle cells, fibroblasts, and epithelial cells as well as the cells involved in the inflammatory response, including macrophages, neutrophils, eosinophils. The redox system is involved in multiple aspects of cell metabolism and cell homeostasis. Critical Issues: Dysregulation of the cellular redox system has consequential effects on cell signaling pathways that are intimately involved in disease progression. The lung is exposed to biomechanical forces (fluid shear stress, cyclic stretch, and pressure) due to the passage of blood through the pulmonary vessels and the distension of the lungs during the breathing cycle. Cells within the lung respond to these forces by activating signal transduction pathways that alter their redox state with both physiologic and pathologic consequences. Future Directions: Here, we will discuss the intimate relationship between biomechanical forces and redox signaling and its role in the development of pulmonary disease. An understanding of the molecular mechanisms induced by biomechanical forces in the pulmonary vasculature is necessary for the development of new therapeutic strategies.
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Affiliation(s)
- Evgeny A Zemskov
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Qing Lu
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Wojciech Ornatowski
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Christina N Klinger
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Ankit A Desai
- Department of Medicine, Indiana University, Indianapolis, Indiana
| | - Emin Maltepe
- Department of Pediatrics, University of California, San Francisco, San Francisco, California
| | - Jason X-J Yuan
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Ting Wang
- Department of Internal Medicine, The University of Arizona Health Sciences, Phoenix, Arizona
| | - Jeffrey R Fineman
- Department of Pediatrics, University of California, San Francisco, San Francisco, California
| | - Stephen M Black
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
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12
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A Prior High-Intensity Exercise Bout Attenuates the Vascular Dysfunction Resulting From a Prolonged Sedentary Bout. J Phys Act Health 2019; 16:916-924. [DOI: 10.1123/jpah.2018-0568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 06/04/2019] [Accepted: 07/14/2019] [Indexed: 11/18/2022]
Abstract
Background: This study sought to determine the impact of an acute prior bout of high-intensity interval aerobic exercise on attenuating the vascular dysfunction associated with a prolonged sedentary bout. Methods: Ten young (24 ± 1 y) healthy males completed two 3-hour sessions of prolonged sitting with (SIT-EX) and without (SIT) a high-intensity interval aerobic exercise session performed immediately prior. Prior to and 3 hours into the sitting bout, leg vascular function was assessed with the passive leg movement technique, and blood samples were obtained from the lower limb to evaluate changes in oxidative stress (malondialdehyde and superoxide dismutase) and inflammation (interleukin-6). Results: No presitting differences in leg vascular function (assessed via passive leg movement technique-induced hyperemia) were revealed between conditions. After 3 hours of prolonged sitting, leg vascular function was significantly reduced in the SIT condition, but unchanged in the SIT-EX. Lower limb blood samples revealed no alterations in oxidative stress, antioxidant capacity, or inflammation in either condition. Conclusions: This study revealed that lower limb vascular dysfunction was significantly attenuated by an acute presitting bout of high-intensity interval aerobic exercise. Further analysis of lower limb blood samples revealed no changes in circulating oxidative stress or inflammation in either condition.
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13
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Garten RS, Darling A, Weggen J, Decker K, Hogwood AC, Michael A, Imthurn B, Mcintyre A. Aerobic training and vascular protection: Insight from altered blood flow patterns. Exp Physiol 2019; 104:1420-1431. [PMID: 31127657 DOI: 10.1113/ep087576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 05/24/2019] [Indexed: 12/14/2022]
Abstract
NEW FINDING What is the central question of this study? This study sought to determine whether prior upper limb aerobic training can attenuate the vascular dysfunction resulting from negative alteration of blood flow patterns. What is the main finding and its importance? We demonstrated that the microvasculature of young men with prior upper limb aerobic training (rowing) was equally susceptible to negatively altered blood flow patterns when compared with untrained control subjects. This finding reveals that aerobic training does not provide adequate protection against this type of vascular insult, highlighting the importance of reducing known vascular insults regardless of training status. ABSTRACT Acute alteration of blood flow patterns can substantially reduce blood vessel function and, if consistently repeated, may chronically reduce vascular health. Aerobic exercise training is associated with improved vascular health, but it is not well understood whether aerobic training-induced vascular adaptations provide protection against acute vascular insults. This study sought to determine whether prior upper limb aerobic training can attenuate the vascular dysfunction resulting from an acute vascular insult (increased retrograde/oscillatory shear). Ten young arm-trained (AT) men (rowers; 22 ± 1 years of age) and 10 untrained (UT) male control subjects (21 ± 3 years of age) were recruited for this study. Subjects completed two brachial artery (BA) flow-mediated dilatation (FMD) tests separated by an acute bout of subdiastolic cuff inflation (SDCI) of the distal forearm. Brachial artery dilatation (normalized for the shear stimulus) and reactive hyperaemia evaluated during the BA FMD test were used to determine conduit artery and microvascular function, respectively. Data were presented as mean values ± SD. The AT group reported significantly greater whole body (peak oxygen uptake; P = 0.01) and forearm aerobic capacity (P < 0.001). The SDCI intervention significantly increased retrograde (P < 0.001) and oscillatory shear (P < 0.001) in both groups. After the SDCI, microvascular function (post-cuff release hyperaemia), but not conduit artery function (shear-induced BA dilatation), was significantly reduced from pre-SDCI values (P = 0.001) independent of group. This study revealed that young men with prior upper limb aerobic training, when compared with untrained control subjects, were equally susceptible to the microvascular dysfunction associated with an acute increase in retrograde/oscillatory shear.
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Affiliation(s)
- Ryan S Garten
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Ashley Darling
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Jennifer Weggen
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Kevin Decker
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Austin C Hogwood
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Austin Michael
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Brandon Imthurn
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
| | - Andrew Mcintyre
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA, USA
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14
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Gu L, Ye P, Li H, Wang Y, Xu Y, Tian Q, Lei G, Zhao C, Gao Z, Zhao W, Tan S. Lunasin attenuates oxidant-induced endothelial injury and inhibits atherosclerotic plaque progression in ApoE -/- mice by up-regulating heme oxygenase-1 via PI3K/Akt/Nrf2/ARE pathway. FASEB J 2019; 33:4836-4850. [PMID: 30601695 DOI: 10.1096/fj.201802251r] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Oxidative stress-induced vascular endothelial cell (VEC) injury is a major mechanism in the initiation and development of atherosclerosis. Lunasin, a soybean-derived 43-aa peptide, has been previously shown to possess potent antioxidant and anti-inflammatory activities other than its established anticancer activities. This study investigated the effects of lunasin on protecting VECs from oxidative damage and inhibiting atherosclerotic plaque progression in apolipoprotein E-deficient (ApoE-/-) mice and explored its underlying mechanism. Biochemical and histologic analyses were performed by using EA.hy926 human VECs and a high-fat diet (HFD) ApoE-/- mouse atherosclerosis model. Our data indicated that lunasin attenuated H2O2-induced, mitochondria-dependent endothelial apoptosis via down-regulating Bax and up-regulating Bcl-2, inhibiting the mitochondrial depolarization, and reducing the release of cytochrome c, as well as decreasing the activation of caspase-9 and caspase-3 in vitro and in vivo. Mechanic studies showed that lunasin significantly up-regulated heme oxygenase-1 via the PI3K/Akt/nuclear factor erythroid 2-related factor 2/antioxidant response element pathway, and reduced H2O2-induced ROS production in VECs, thereby attenuating oxidant-induced endothelial injury and inhibiting atherosclerotic plaque progression in ApoE-/- mice. In conclusion, our in vitro and in vivo data suggest that lunasin protects VECs from oxidative damage by enhancing heme oxygenase-1 expression via activation of the PI3K/Akt/nuclear factor erythroid 2-related factor 2/antioxidant response element pathway and inhibiting mitochondria-dependent apoptosis, thereby effectively attenuating atherosclerosis in HFD-fed ApoE-/- mice. Lunasin may act as a potential therapeutic agent for the prevention and treatment of atherosclerosis.-Gu, L., Ye, P., Li, H., Wang, Y., Xu, Y., Tian, Q., Lei, G., Zhao, C., Gao, Z., Zhao, W., Tan, S. Lunasin attenuates oxidant-induced endothelial injury and inhibits atherosclerotic plaque progression in ApoE-/- mice by up-regulating heme oxygenase-1 via PI3K/Akt/Nrf2/ARE pathway.
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Affiliation(s)
- Lili Gu
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Pei Ye
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Hengli Li
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Yue Wang
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Yaqiong Xu
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Qinghua Tian
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Gaoxin Lei
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Cheng Zhao
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Zhan Gao
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Wenfeng Zhao
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Shuhua Tan
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
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15
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Li Z, Yulei J, Yaqing J, Jinmin Z, Xinyong L, Jing G, Min L. Protective effects of tetramethylpyrazine analogue Z-11 on cerebral ischemia reperfusion injury. Eur J Pharmacol 2018; 844:156-164. [PMID: 30502344 DOI: 10.1016/j.ejphar.2018.11.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 11/18/2022]
Abstract
The aim of our study was to investigate the effects of a new synthetic compound (E) -1- (E) -1- (2- hydroxy -5- chlorophenyl) -3- (3, 5, 6- three methyl pyrazine -2- based) -2- propylene -1 ketone, Z-11, a tetramethylpyrazine analogue, on cerebral ischemia reperfusion injury and the underlying mechanism. 240-260 g adult male Wistar rats were subjected to middle cerebral artery occlusion for 2 h, followed by 22 h of reperfusion. Z-11 (1.7, 3.4 and 6.8 mg/kg, i.p.), Edaravone (3 mg/kg, i.p.) and DMSO (1‰, i.p.) was administered at 2 h after the onset of ischemia. The rats' neurological score, infarct volume, and body weight change were tested, and some oxidative stress markers such as superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) contents were evaluated after 22 h of reperfusion. Results showed that neurologic deficit, infarct volume and body weight change were ameliorated after cerebral ischemia reperfusion, and that Z-11 exhibits an excellent effect at a dosage of 6.8 mg/kg. This dose also reduced the content of MDA, and upregulated SOD activity and GSH content. Similarly, 6.8 mg/kg Z-11 treatment inhibited the reactive oxygen species content and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, with the protein levels of Ras-related C3 botulinum toxin substrate1(Rac-1) and mitogenic oxidase (Nox2) downregulated even further. Moreover, the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream anti-oxidant protein heme oxygenase-1 (HO-1) were upregulated. This indicates that Z-11 could play a protective role in cerebral ischemia-reperfusion injury, and that the protective effect of Z-11 may be related to improvements in the antioxidant capacity of brain tissue. The mechanisms are associated with enhancing oxidant defence systems via the activation of Nrf2/HO-1 and Rac-1/NADPH oxidase pathways.
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Affiliation(s)
- Zhai Li
- Department of Pharmacy, Qingdao Municipal Hospital, Qingdao 266071, China
| | - Jia Yulei
- Department of Pharmacy, Qingdao Municipal Hospital, Qingdao 266071, China
| | - Ji Yaqing
- Department of Neurology, Eighth People's Hospital Affiliated to Qiingdao University, Qingdao 266003, China
| | - Zou Jinmin
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Liu Xinyong
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
| | - Gao Jing
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao 266000, China
| | - Liu Min
- Department of Pharmacy, Qingdao Municipal Hospital, Qingdao 266071, China
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16
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Gogoi K, Manna P, Dey T, Kalita J, Unni BG, Ozah D, Baruah PK. Circulatory heavy metals (cadmium, lead, mercury, and chromium) inversely correlate with plasma GST activity and GSH level in COPD patients and impair NOX4/Nrf2/GCLC/GST signaling pathway in cultured monocytes. Toxicol In Vitro 2018; 54:269-279. [PMID: 30359721 DOI: 10.1016/j.tiv.2018.10.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/08/2018] [Accepted: 10/19/2018] [Indexed: 01/17/2023]
Abstract
This study aims to examine the hypothesis that circulatory heavy metals may be associated with lung function decline and lower plasma GST activity and GSH level in COPD patients via activating monocytes mediated by impairing the NOX4/Nrf2/GCLC/GST signaling pathway. Results showed that the blood levels of heavy metals (cadmium, lead, mercury, and chromium) were significantly higher in COPD patients of coal mine site compared to the healthy controls. The levels of heavy metals in COPD patients were significantly and negatively correlated with lung function, GST activity, and GSH level. Using flowcytometry, fluorescence spectroscopy, and immunoblotting studies we have further demonstrated that treatment with individual heavy metals dose-dependently increased the NOX4 protein expression, intracellular ROS production, and decreased the Nrf2, GCLC, and GST protein expression, GST activity, and GSH level in THP-1 monocytes. None of the treatment caused any change in cell viability compared to control. In conclusion, this study suggests that circulatory heavy metals in COPD patients of coal mine site weakened the lung function, decreased the plasma GST activity and GSH level via impairing the NOX4/Nrf2/GCLC/GST signaling pathway in monocytes, which may cause monocyte activation and initiate the COPD pathophysiology.
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Affiliation(s)
- Kabita Gogoi
- Biological Sciences and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, Assam, India; Academy of Scientific and Innovative Research, CSIR-North East Institute of Science and Technology Campus, Jorhat 785006, Assam, India
| | - Prasenjit Manna
- Biological Sciences and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, Assam, India; Academy of Scientific and Innovative Research, CSIR-North East Institute of Science and Technology Campus, Jorhat 785006, Assam, India
| | - Tapan Dey
- Biological Sciences and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, Assam, India
| | - Jatin Kalita
- Academy of Scientific and Innovative Research, CSIR-North East Institute of Science and Technology Campus, Jorhat 785006, Assam, India; Research Planning and Business Development Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, Assam, India.
| | - Bala Gopalan Unni
- Research Cell, Assam Downtown University, Guwahati 781026, Assam, India
| | - Dibyajyoti Ozah
- Clinical Centre, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India
| | - Pranab Kumar Baruah
- Clinical Centre, CSIR-North East Institute of Science and Technology, Jorhat, Assam, India
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17
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Garten RS, Hogwood AC, Weggen JB, Fralin RC, LaRosa K, Lee D, Michael A, Scott M. Aerobic training status does not attenuate prolonged sitting-induced lower limb vascular dysfunction. Appl Physiol Nutr Metab 2018; 44:425-433. [PMID: 30257099 DOI: 10.1139/apnm-2018-0420] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This study examined if the degree of aerobic training protects against the lower limb vascular dysfunction associated with a prolonged sitting bout. Ten young, aerobically trained (AT) and 10 young, untrained (UT) individuals completed a prolonged (3 h) sitting bout. Leg vascular function was measured prior to and at 1.5 and 3 h into the prolonged sitting bout using the passive leg movement (PLM) technique. PLM-induced hyperemia was significantly reduced from baseline at 1.5 and 3 h into the prolonged sitting bout in both groups when evaluated as peak change in leg blood flow from baseline (Δ LBF) (UT: 956 ± 140, 586 ± 80, and 599 ± 96 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 955 ± 183, 789 ± 193, and 712 ± 131 mL·min-1 at baseline, 1.5 h, and 3 h, respectively) and LBF area under the curve (UT: 283 ± 73, 134 ± 31, and 164 ± 42 mL·min-1 at baseline, 1.5 h, and 3 h, respectively; AT: 336 ± 86, 242 ± 86, and 245 ± 73 mL·min-1 at baseline, 1.5 h, and 3 h, respectively), but no significant differences between groups were revealed. No significant correlations were observed when examining the relationship between maximal oxygen uptake (relative and absolute) and reductions in leg vascular function at 1.5 and 3 h into the prolonged sitting bout. This study revealed that aerobic training did not provide a protective effect against prolonged sitting-induced lower limb vascular dysfunction and further highlights the importance of reducing excessive sitting in all populations.
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Affiliation(s)
- Ryan S Garten
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Austin C Hogwood
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Jennifer B Weggen
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - R Carson Fralin
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Kathryn LaRosa
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - David Lee
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Austin Michael
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
| | - Matthew Scott
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA.,Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, VA 23284-2020, USA
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18
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Sun X, Yang Y, Shi J, Wang C, Yu Z, Zhang H. NOX4- and Nrf2-mediated oxidative stress induced by silver nanoparticles in vascular endothelial cells. J Appl Toxicol 2017; 37:1428-1437. [DOI: 10.1002/jat.3511] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 07/11/2017] [Accepted: 07/11/2017] [Indexed: 01/07/2023]
Affiliation(s)
- Xia Sun
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
| | - Yi Yang
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
- University of Chinese Academy of Sciences; Beijing 100049 China
| | - Junpeng Shi
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
| | - Chengcheng Wang
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
- University of Chinese Academy of Sciences; Beijing 100049 China
| | - Zhenfeng Yu
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
- University of Chinese Academy of Sciences; Beijing 100049 China
| | - Hongwu Zhang
- Key Lab of Urban Pollutant Conversion, Institute of Urban Environment; Chinese Academy of Sciences; Xiamen 361021 China
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19
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Giebe S, Cockcroft N, Hewitt K, Brux M, Hofmann A, Morawietz H, Brunssen C. Cigarette smoke extract counteracts atheroprotective effects of high laminar flow on endothelial function. Redox Biol 2017; 12:776-786. [PMID: 28432984 PMCID: PMC5397582 DOI: 10.1016/j.redox.2017.04.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 04/04/2017] [Indexed: 02/04/2023] Open
Abstract
Tobacco smoking and hemodynamic forces are key stimuli in the development of endothelial dysfunction and atherosclerosis. High laminar flow has an atheroprotective effect on the endothelium and leads to a reduced response of endothelial cells to cardiovascular risk factors compared to regions with disturbed or low laminar flow. We hypothesize that the atheroprotective effect of high laminar flow could delay the development of endothelial dysfunction caused by cigarette smoking. Primary human endothelial cells were stimulated with increasing dosages of aqueous cigarette smoke extract (CSEaq). CSEaq reduced cell viability in a dose-dependent manner. The main mediator of cellular adaption to oxidative stress, nuclear factor erythroid 2-related factor 2 (NRF2) and its target genes heme oxygenase (decycling) 1 (HMOX1) or NAD(P)H quinone dehydrogenase 1 (NQO1) were strongly increased by CSEaq in a dose-dependent manner. High laminar flow induced elongation of endothelial cells in the direction of flow, activated the AKT/eNOS pathway, increased eNOS expression, phosphorylation and NO release. These increases were inhibited by CSEaq. Pro-inflammatory adhesion molecules intercellular adhesion molecule-1 (ICAM1), vascular cell adhesion molecule-1 (VCAM1), selectin E (SELE) and chemokine (C-C motif) ligand 2 (CCL2/MCP-1) were increased by CSEaq. Low laminar flow induced VCAM1 and SELE compared to high laminar flow. High laminar flow improved endothelial wound healing. This protective effect was inhibited by CSEaq in a dose-dependent manner through the AKT/eNOS pathway. Low as well as high laminar flow decreased adhesion of monocytes to endothelial cells. Whereas, monocyte adhesion was increased by CSEaq under low laminar flow, this was not evident under high laminar flow. This study shows the activation of major atherosclerotic key parameters by CSEaq. Within this process, high laminar flow is likely to reduce the harmful effects of CSEaq to a certain degree. The identified molecular mechanisms might be useful for development of alternative therapy concepts.
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Affiliation(s)
- Sindy Giebe
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Natalia Cockcroft
- Research & Development, British American Tobacco, Southampton, United Kingdom
| | - Katherine Hewitt
- Research & Development, British American Tobacco, Southampton, United Kingdom
| | - Melanie Brux
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Anja Hofmann
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany.
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany.
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Cybularz M, Langbein H, Zatschler B, Brunssen C, Deussen A, Matschke K, Morawietz H. Endothelial function and gene expression in perivascular adipose tissue from internal mammary arteries of obese patients with coronary artery disease. ATHEROSCLEROSIS SUPP 2017; 30:149-158. [PMID: 29096831 DOI: 10.1016/j.atherosclerosissup.2017.05.042] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND AND AIMS Obesity is a risk factor for endothelial dysfunction and atherosclerosis. However, perivascular adipose tissue can release adipokines and other unknown adipose-derived relaxing factors. Therefore, we investigated the impact of obesity on vascular function and expression of genes in perivascular adipose tissue from internal mammary arteries of patients with coronary artery disease undergoing coronary artery bypass grafting. METHODS The vessel function was compared between groups of patients with a body-mass index (BMI) between 25 and 30 kg/m2. The groups did not differ in age, gender (males), and ejection fraction. Vascular segments of internal mammary arteries were examined in a Mulvany myograph. Following preconstriction with noradrenaline, dose-response curves were assessed for relaxation with acetylcholine and sodium nitroprusside. RESULTS Maximum contraction in response to potassium and noradrenaline was increased in obese patients with a BMI >30 kg/m2. EC50 of endothelium-dependent relaxation was impaired in patients with a BMI above 25, but below 30 kg/m2. Sodium nitroprusside-mediated maximal relaxation was not different between study groups. Integrin alpha X chain (ITGAX/CD11c) and macrophage mannose receptor (MRC1/CD206) expression was reduced in perivascular adipose tissue of patients with a BMI above 30 kg/m2, while adiponectin (ADPQ) expression was increased in the same tissue. CONCLUSION Our data suggest a partially reduced endothelial function in internal mammary arteries of adipose patients with a BMI between 25 and 30 kg/m2 undergoing coronary artery bypass grafting surgery. Increased adiponectin expression in perivascular tissue might contribute to maintenance of endothelial function in obese patients with a BMI above 30 kg/m2.
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Affiliation(s)
- Maria Cybularz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Heike Langbein
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Birgit Zatschler
- Institute of Physiology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Andreas Deussen
- Institute of Physiology, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Klaus Matschke
- Department of Cardiac Surgery, Herzzentrum Dresden, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 76, 01307 Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany.
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21
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Müller G, Meissner S, Walther J, Koch E, Morawietz H. In vivo imaging of murine vasodynamics analyzing different mouse strains by optical coherence tomography. ATHEROSCLEROSIS SUPP 2017; 30:311-318. [PMID: 29096856 DOI: 10.1016/j.atherosclerosissup.2017.05.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND AIMS We tried to circumvent the limitations of standard organ chamber experiments using in vivo optical coherence tomography (OCT) to analyze the vascular function of small arteries in different mouse strains. METHODS OCT images were acquired with a two-axis galvanometer scanner head. Time series (3 frames per second, 300 × 512 pixel per frame) of cross-sectional images were analyzed with image processing software measuring the time course of vessel lumen dynamics. Vascular function of murine saphenous artery of male C57BL/6 (wild-type) and hypercholesterolemic LDLR knockout (LDLR-/-) mice was analyzed at 6 weeks and after 14 weeks feeding a control or high-fat diet containing 21.2% butter fat and 2.1 mg/kg cholesterol. Vasoconstriction and vasodilation was analyzed by OCT in response to 80 mM K+ and 1 mM SNP. RESULTS The OCT technique allowed determination of inner diameter, flow resistance, maximal velocity of diameter change and time to half-maximal diameter change in murine saphenous arteries of wild-type and LDLR-/- mice. LDLR-/- had impaired vasodilation and changes in vasodynamics after 14 weeks on control or high-fat diet, compared to wild-type mice. The diameter of the saphenous artery of LDLR-/- mice was reduced after vasoconstriction (38 ± 7 μm vs 12 ± 6 μm) and vasodilation (245 ± 8 μm vs 220 ± 10 μm) (P < 0.05 vs C57BL/6). CONCLUSION OCT was used as an innovative method to image vascular function of small arteries of wild-type and hypercholesterolemic LDLR-/- mice after high-fat diet. The method offers the ability to display differences in the vasodynamics at early stages of endothelial dysfunction in vivo.
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Affiliation(s)
- Gregor Müller
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Sven Meissner
- Clinical Sensoring and Monitoring, Department of Anesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Julia Walther
- Clinical Sensoring and Monitoring, Department of Anesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Edmund Koch
- Clinical Sensoring and Monitoring, Department of Anesthesiology and Intensive Care Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany.
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22
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Brunssen C, Giebe S, Hofmann A, Brux M, Morawietz H. Evaluation of Cytotoxic, Oxidative, and Pro-Inflammatory Effects of Aqueous Cigarette Smoke Extract on Human Monocytes: A Potential Model System for Assessment of Next-Generation Tobacco and Nicotine Products. ACTA ACUST UNITED AC 2017. [DOI: 10.1089/aivt.2016.0037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Sindy Giebe
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Anja Hofmann
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Melanie Brux
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, Medical Faculty Carl Gustav Carus and University Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Dresden, Germany
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23
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Chistiakov DA, Orekhov AN, Bobryshev YV. Effects of shear stress on endothelial cells: go with the flow. Acta Physiol (Oxf) 2017; 219:382-408. [PMID: 27246807 DOI: 10.1111/apha.12725] [Citation(s) in RCA: 264] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 02/17/2016] [Accepted: 05/30/2016] [Indexed: 12/11/2022]
Abstract
Haemodynamic forces influence the functional properties of vascular endothelium. Endothelial cells (ECs) have a variety of receptors, which sense flow and transmit mechanical signals through mechanosensitive signalling pathways to recipient molecules that lead to phenotypic and functional changes. Arterial architecture varies greatly exhibiting bifurcations, branch points and curved regions, which are exposed to various flow patterns. Clinical studies showed that atherosclerotic plaques develop preferentially at arterial branches and curvatures, that is in the regions exposed to disturbed flow and shear stress. In the atheroprone regions, the endothelium has a proinflammatory phenotype associated with low nitric oxide production, reduced barrier function and increased proadhesive, procoagulant and proproliferative properties. Atheroresistant regions are exposed to laminar flow and high shear stress that induce prosurvival antioxidant signals and maintain the quiescent phenotype in ECs. Indeed, various flow patterns contribute to phenotypic and functional heterogeneity of arterial endothelium whose response to proatherogenic stimuli is differentiated. This may explain the preferential development of endothelial dysfunction in arterial sites with disturbed flow.
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Affiliation(s)
- D. A. Chistiakov
- Department of Medical Nanobiotechnology; Pirogov Russian State Medical University; Moscow Russia
| | - A. N. Orekhov
- Institute of General Pathology and Pathophysiology; Russian Academy of Medical Sciences; Moscow Russia
- Institute for Atherosclerosis Research; Skolkovo Innovative Center; Moscow Russia
- Department of Biophysics; Biological Faculty; Moscow State University; Moscow Russia
| | - Y. V. Bobryshev
- Institute of General Pathology and Pathophysiology; Russian Academy of Medical Sciences; Moscow Russia
- Faculty of Medicine and St Vincent's Centre for Applied Medical Research; University of New South Wales; Sydney NSW Australia
- School of Medicine; University of Western Sydney; Campbelltown NSW Australia
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24
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A novel role for small molecule glycomimetics in the protection against lipid-induced endothelial dysfunction: Involvement of Akt/eNOS and Nrf2/ARE signaling. Biochim Biophys Acta Gen Subj 2017; 1861:3311-3322. [DOI: 10.1016/j.bbagen.2016.08.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 07/20/2016] [Accepted: 08/19/2016] [Indexed: 02/07/2023]
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25
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Nie H, Xue X, Liu G, Guan G, Liu H, Sun L, Zhao L, Wang X, Chen Z. Nitro-oleic acid ameliorates oxygen and glucose deprivation/re-oxygenation triggered oxidative stress in renal tubular cells via activation of Nrf2 and suppression of NADPH oxidase. Free Radic Res 2016; 50:1200-1213. [PMID: 27545328 DOI: 10.1080/10715762.2016.1225955] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nitroalkene derivative of oleic acid (OA-NO2), due to its ability to mediate revisable Michael addition, has been demonstrated to have various biological properties and become a therapeutic agent in various diseases. Though its antioxidant properties have been reported in different models of acute kidney injury (AKI), the mechanism by which OA-NO2 attenuates intracellular oxidative stress is not well investigated. Here, we elucidated the anti-oxidative mechanism of OA-NO2 in an in vitro model of renal ischemia/reperfusion (I/R) injury. Human tubular epithelial cells were subjected to oxygen and glucose deprivation/re-oxygenation (OGD/R) injury. Pretreatment with OA-NO2 (1.25 μM, 45 min) attenuated OGD/R triggered reactive oxygen species (ROS) generation and subsequent mitochondrial membrane potential disruption. This action was mediated via up-regulating endogenous antioxidant defense components including superoxide dismutase (SOD1), heme oxygenase 1 (HO-1), and γ-glutamyl cysteine ligase modulatory subunits (GCLM). Moreover, subcellular fractionation analyses demonstrated that OA-NO2 promoted nuclear translocation of nuclear factor-E2- related factor-2 (Nrf2) and Nrf2 siRNA partially abrogated these protective effects. In addition, OA-NO2 inhibited NADPH oxidase activation and NADPH oxidase 4 (NOX4), NADPH oxidase 2 (NOX2) and p22phox up-regulation after OGD/R injury, which was not relevant to Nrf2. These results contribute to clarify that the mechanism of OA-NO2 reno-protection involves both inhibition of NADPH oxidase activity and induction of SOD1, Nrf2-dependent HO-1, and GCLM.
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Affiliation(s)
- Huibin Nie
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China.,b Department of Nephrology , Chengdu First People's Hospital , Chengdu , Sichuan , PR China
| | - Xia Xue
- c Department of Pharmacy , The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Gang Liu
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Guangju Guan
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Haiying Liu
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Lina Sun
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Long Zhao
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Xueling Wang
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
| | - Zhixin Chen
- a Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Shandong University , Jinan , Shandong , PR China
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26
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Hakami NY, Dusting GJ, Peshavariya HM. Trichostatin A, a histone deacetylase inhibitor suppresses NADPH Oxidase 4-Derived Redox Signalling and Angiogenesis. J Cell Mol Med 2016; 20:1932-44. [PMID: 27297729 PMCID: PMC5020625 DOI: 10.1111/jcmm.12885] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 04/26/2016] [Indexed: 02/06/2023] Open
Abstract
Histone deacetylase (HDAC) inhibitors are known to suppress abnormal development of blood vessels. Angiogenic activity in endothelial cells depends upon NADPH oxidase 4 (Nox4)-dependent redox signalling. We set out to study whether the HDAC inhibitor trichostatin A (TSA) affects Nox4 expression and angiogenesis. Nox4 expression was measured by real time PCR and Western blot analysis in endothelial cells. Hydrogen peroxide (H2 O2 ) was measured by amplex(®) red assay in endothelial cells. Nox4 was knocked down by Nox4 shRNA. In vitro angiogenic activities such migration and tubulogenesis were assessed using wound healing and Matrigel assays, respectively. In vivo angiogenic activity was assessed using subcutaneous sponge assay in C57Bl/6 and Nox4-deficient mice. Trichostatin A reduced Nox4 expression in a time- and concentration-dependent manner. Both TSA and Nox4 silencing decreased Nox4 protein and H2 O2 . Mechanistically, TSA reduced expression of Nox4 via ubiquitination of p300- histone acetyltransferase (p300-HAT). Thus, blocking of the ubiquitination pathway using an inhibitor of ubiquitin-activating enzyme E1 (PYR-41) prevented TSA inhibition of Nox4 expression. Trichostatin A also reduced migration and tube formation, and these effects were not observed in Nox4-deficient endothelial cells. Finally, transforming growth factor beta1 (TGFβ1) enhanced angiogenesis in sponge model in C57BL/6 mice. This response to TGFβ1 was substantially reduced in Nox4-deficient mice. Similarly intraperitoneal infusion of TSA (1 mg/kg) also suppressed TGFβ1-induced angiogenesis in C57BL/6 mice. Trichostatin A reduces Nox4 expression and angiogenesis via inhibition of the p300-HAT-dependent pathway. This mechanism might be exploited to prevent aberrant angiogenesis in diabetic retinopathy, complicated vascular tumours and malformations.
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Affiliation(s)
- Nora Y Hakami
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia.,Ophthalmology, University of Melbourne, Department of Surgery, East Melbourne, VIC, Australia.,Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, VIC, Australia.,Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Gregory J Dusting
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia.,Ophthalmology, University of Melbourne, Department of Surgery, East Melbourne, VIC, Australia
| | - Hitesh M Peshavariya
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia. .,Ophthalmology, University of Melbourne, Department of Surgery, East Melbourne, VIC, Australia.
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27
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Siu KL, Gao L, Cai H. Differential Roles of Protein Complexes NOX1-NOXO1 and NOX2-p47phox in Mediating Endothelial Redox Responses to Oscillatory and Unidirectional Laminar Shear Stress. J Biol Chem 2016; 291:8653-62. [PMID: 26826128 DOI: 10.1074/jbc.m115.713149] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Indexed: 11/06/2022] Open
Abstract
The endothelium is exposed to various flow patterns such as vasoprotective unidirectional laminar shear stress (LSS) and atherogenic oscillatory shear stress (OSS). A software-controlled, valve-operated OsciFlow device with parallel chambers was used to apply LSS and OSS to endothelial cells. Although LSS inhibited superoxide over time, OSS time-dependently increased superoxide production from endothelial cells. Immunocytochemical staining revealed that, at resting state, p47phox colocalizes with NOX2, whereas NOXO1 colocalizes with NOX1. RNAi of p47phox had no effects on superoxide or NO production in response to OSS but significantly reduced NO production in LSS, implicating a p47phox-bound NADPH oxidase (NOX) in mediating basal NO production. Indeed, RNAi of p47phox inhibited endothelial nitric oxide synthase (eNOS) serine 1179 phosphorylation, whereas PEG-catalase scavenging of intracellular hydrogen peroxide or RNAi of NOX2 produced similar results, indicating a role of NOX2/p47phox-derived hydrogen peroxide in mediating the basal activity of NO production from eNOS. In contrast, RNAi of NOXO1 resulted in no significant changes in NO and superoxide levels in response to LSS but significantly reduced superoxide while increasing NO in response to OSS. Furthermore, we identified, for the first time, that OSS uncouples eNOS, which was corrected by RNAi of NOXO1. In summary, LSS activates the NOX2-p47phox complex to activate eNOS phosphorylation and NO production. OSS instead activates the NOX1-NOXO1 complex to uncouple eNOS. These results demonstrate differential roles of NOXs in modulating the redox state in response to different shear stresses, which may promote the development of novel therapeutic agents to mimic the protective effects of LSS while inhibiting the injurious effects of OSS.
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Affiliation(s)
- Kin Lung Siu
- From the Divisions of Molecular Medicine and Cardiology, Departments of Anesthesiology and Medicine, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California 90095
| | - Ling Gao
- From the Divisions of Molecular Medicine and Cardiology, Departments of Anesthesiology and Medicine, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California 90095
| | - Hua Cai
- From the Divisions of Molecular Medicine and Cardiology, Departments of Anesthesiology and Medicine, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California 90095
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28
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McSweeney SR, Warabi E, Siow RCM. Nrf2 as an Endothelial Mechanosensitive Transcription Factor: Going With the Flow. Hypertension 2015; 67:20-9. [PMID: 26597822 DOI: 10.1161/hypertensionaha.115.06146] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Shane R McSweeney
- From the Cardiovascular Division, British Heart Foundation Centre of Research Excellence, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom (S.R.M., R.C.M.S.); and Faculty of Medicine, University of Tsukuba, Tsukuba, Japan (E.W.)
| | - Eiji Warabi
- From the Cardiovascular Division, British Heart Foundation Centre of Research Excellence, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom (S.R.M., R.C.M.S.); and Faculty of Medicine, University of Tsukuba, Tsukuba, Japan (E.W.)
| | - Richard C M Siow
- From the Cardiovascular Division, British Heart Foundation Centre of Research Excellence, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom (S.R.M., R.C.M.S.); and Faculty of Medicine, University of Tsukuba, Tsukuba, Japan (E.W.).
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29
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Otto S, Deussen A, Zatschler B, Müller B, Neisser A, Barth K, Morawietz H, Kopaliani I. A novel role of endothelium in activation of latent pro-membrane type 1 MMP and pro-MMP-2 in rat aorta. Cardiovasc Res 2015; 109:409-18. [PMID: 26598508 DOI: 10.1093/cvr/cvv256] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 11/14/2015] [Indexed: 11/13/2022] Open
Abstract
AIMS Aortic stiffness is an independent risk factor for progression of cardiovascular diseases. Degradation of elastic fibres in aorta due to angiotensin II (ANGII)-stimulated overactivation of latent membrane type 1 matrix metalloproteinase (MT1MMP) and matrix metalloproteinase-2 (MMP2) is regarded to represent an important cause of aortic stiffness. Therefore, clarification of the causal mechanisms triggering the overactivation of these MMPs is of utmost importance. This study addresses the endothelium as a novel key activator of latent pro-MT1MMP and pro-MMP2 in rat aorta. METHODS AND RESULTS Using a co-culture model of rat aortic endothelial cells (ECs) and smooth muscle cells (SMCs), we found that ANGII stimulation resulted in activation of latent pro-MT1MMP and pro-MMP2 in SMCs exclusively when co-cultured with ECs (assessed with western blot and gelatin zymography, respectively). EC-specific AT1 receptor stimulation triggered endothelin-1 release and paracrine action on SMCs. Endothelin-1 increased expression and activity of pro-protein convertase furin in SMCs via endothelin receptor type A (assessed with qPCR and furin activity assay, respectively). Consequently, furin acted in two ways. First, it increased the activation of latent pro-MT1MMP and, second, it activated pro-αvβ3 integrin. Both pathways led to overactivation of latent pro-MMP2. In vitro findings in the co-culture model were fully consistent with the ex vivo findings obtained in isolated rat aorta. CONCLUSIONS We propose that the endothelium under ANGII stimulation acts as a novel and key activator of latent pro-MT1MMP and pro-MMP2 in SMCs of rat aorta. Therefore, endothelium may critically contribute to pathophysiology of aortic stiffness.
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Affiliation(s)
- Sören Otto
- Department of Physiology, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Andreas Deussen
- Department of Physiology, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Birgit Zatschler
- Department of Physiology, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Bianca Müller
- Department of Physiology, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Anja Neisser
- Department of Anatomy, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Kathrin Barth
- Department of Anatomy, Faculty of Medicine, Technische Universität Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University, Hospital Carl Gustav Carus Dresden, Technische Universität Dresden, Germany
| | - Irakli Kopaliani
- Department of Physiology, Faculty of Medicine, Technische Universität Dresden, Germany
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30
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Rozycki M, Bialik JF, Speight P, Dan Q, Knudsen TET, Szeto SG, Yuen DA, Szászi K, Pedersen SF, Kapus A. Myocardin-related Transcription Factor Regulates Nox4 Protein Expression: LINKING CYTOSKELETAL ORGANIZATION TO REDOX STATE. J Biol Chem 2015; 291:227-43. [PMID: 26555261 DOI: 10.1074/jbc.m115.674606] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Indexed: 01/06/2023] Open
Abstract
TGFβ-induced expression of the NADPH oxidase Nox4 is essential for fibroblast-myofibroblast transition. Rho has been implicated in Nox4 regulation, but the underlying mechanisms are largely unknown. Myocardin-related transcription factor (MRTF), a Rho/actin polymerization-controlled coactivator of serum response factor, drives myofibroblast transition from various precursors. We have shown that TGFβ is necessary but insufficient for epithelial-myofibroblast transition in intact epithelia; the other prerequisite is the uncoupling of intercellular contacts, which induces Rho-dependent nuclear translocation of MRTF. Because the Nox4 promoter harbors a serum response factor/MRTF cis-element (CC(A/T)6GG box), we asked if MRTF (and thus cytoskeleton organization) could regulate Nox4 expression. We show that Nox4 protein is robustly induced in kidney tubular cells exclusively by combined application of contact uncoupling and TGFβ. Nox4 knockdown abrogates epithelial-myofibroblast transition-associated reactive oxygen species production. Laser capture microdissection reveals increased Nox4 expression in the tubular epithelium also during obstructive nephropathy. MRTF down-regulation/inhibition suppresses TGFβ/contact disruption-provoked Nox4 protein and mRNA expression, Nox4 promoter activation, and reactive oxygen species production. Mutation of the CC(A/T)6GG box eliminates the synergistic activation of the Nox4 promoter. Jasplakinolide-induced actin polymerization synergizes with TGFβ to facilitate MRTF-dependent Nox4 mRNA expression/promoter activation. Moreover, MRTF inhibition prevents Nox4 expression during TGFβ-induced fibroblast-myofibroblast transition as well. Although necessary, MRTF is insufficient; Nox4 expression also requires TGFβ-activated Smad3 and TAZ/YAP, two contact- and cytoskeleton-regulated Smad3-interacting coactivators. Down-regulation/inhibition of TAZ/YAP mitigates injury-induced epithelial Nox4 expression in vitro and in vivo. These findings uncover new MRTF- and TAZ/YAP-dependent mechanisms, which link cytoskeleton remodeling and redox state and impact epithelial plasticity and myofibroblast transition.
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Affiliation(s)
- Matthew Rozycki
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital
| | - Janne Folke Bialik
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital, the Department of Biology, Section for Cell Biology and Physiology, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Pam Speight
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital
| | - Qinghong Dan
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital
| | - Teresa E T Knudsen
- the Department of Biology, Section for Cell Biology and Physiology, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - Stephen G Szeto
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital
| | - Darren A Yuen
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital
| | - Katalin Szászi
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital, Departments of Surgery and
| | - Stine F Pedersen
- the Department of Biology, Section for Cell Biology and Physiology, University of Copenhagen, Copenhagen DK-2100, Denmark
| | - András Kapus
- From the Keenan Research Centre for Biomedical Science of the St. Michael's Hospital, Departments of Surgery and Biochemistry, University of Toronto, Toronto, Ontario M5B 1T8, Canada and
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Tebay LE, Robertson H, Durant ST, Vitale SR, Penning TM, Dinkova-Kostova AT, Hayes JD. Mechanisms of activation of the transcription factor Nrf2 by redox stressors, nutrient cues, and energy status and the pathways through which it attenuates degenerative disease. Free Radic Biol Med 2015; 88:108-146. [PMID: 26122708 PMCID: PMC4659505 DOI: 10.1016/j.freeradbiomed.2015.06.021] [Citation(s) in RCA: 597] [Impact Index Per Article: 66.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 12/11/2022]
Abstract
UNLABELLED Nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) regulates the basal and stress-inducible expression of a battery of genes encoding key components of the glutathione-based and thioredoxin-based antioxidant systems, as well as aldo-keto reductase, glutathione S-transferase, and NAD(P)H quinone oxidoreductase-1 drug-metabolizing isoenzymes along with multidrug-resistance-associated efflux pumps. It therefore plays a pivotal role in both intrinsic resistance and cellular adaptation to reactive oxygen species (ROS) and xenobiotics. Activation of Nrf2 can, however, serve as a double-edged sword because some of the genes it induces may contribute to chemical carcinogenesis by promoting futile redox cycling of polycyclic aromatic hydrocarbon metabolites or confer resistance to chemotherapeutic drugs by increasing the expression of efflux pumps, suggesting its cytoprotective effects will vary in a context-specific fashion. In addition to cytoprotection, Nrf2 also controls genes involved in intermediary metabolism, positively regulating those involved in NADPH generation, purine biosynthesis, and the β-oxidation of fatty acids, while suppressing those involved in lipogenesis and gluconeogenesis. Nrf2 is subject to regulation at multiple levels. Its ability to orchestrate adaptation to oxidants and electrophiles is due principally to stress-stimulated modification of thiols within one of its repressors, the Kelch-like ECH-associated protein 1 (Keap1), which is present in the cullin-3 RING ubiquitin ligase (CRL) complex CRLKeap1. Thus modification of Cys residues in Keap1 blocks CRLKeap1 activity, allowing newly translated Nrf2 to accumulate rapidly and induce its target genes. The ability of Keap1 to repress Nrf2 can be attenuated by p62/sequestosome-1 in a mechanistic target of rapamycin complex 1 (mTORC1)-dependent manner, thereby allowing refeeding after fasting to increase Nrf2-target gene expression. In parallel with repression by Keap1, Nrf2 is also repressed by β-transducin repeat-containing protein (β-TrCP), present in the Skp1-cullin-1-F-box protein (SCF) ubiquitin ligase complex SCFβ-TrCP. The ability of SCFβ-TrCP to suppress Nrf2 activity is itself enhanced by prior phosphorylation of the transcription factor by glycogen synthase kinase-3 (GSK-3) through formation of a DSGIS-containing phosphodegron. However, formation of the phosphodegron in Nrf2 by GSK-3 is inhibited by stimuli that activate protein kinase B (PKB)/Akt. In particular, PKB/Akt activity can be increased by phosphoinositide 3-kinase and mTORC2, thereby providing an explanation of why antioxidant-responsive element-driven genes are induced by growth factors and nutrients. Thus Nrf2 activity is tightly controlled via CRLKeap1 and SCFβ-TrCP by oxidative stress and energy-based signals, allowing it to mediate adaptive responses that restore redox homeostasis and modulate intermediary metabolism. Based on the fact that Nrf2 influences multiple biochemical pathways in both positive and negative ways, it is likely its dose-response curve, in terms of susceptibility to certain degenerative disease, is U-shaped. Specifically, too little Nrf2 activity will lead to loss of cytoprotection, diminished antioxidant capacity, and lowered β-oxidation of fatty acids, while conversely also exhibiting heightened sensitivity to ROS-based signaling that involves receptor tyrosine kinases and apoptosis signal-regulating kinase-1. By contrast, too much Nrf2 activity disturbs the homeostatic balance in favor of reduction, and so may have deleterious consequences including overproduction of reduced glutathione and NADPH, the blunting of ROS-based signal transduction, epithelial cell hyperplasia, and failure of certain cell types to differentiate correctly. We discuss the basis of a putative U-shaped Nrf2 dose-response curve in terms of potentially competing processes relevant to different stages of tumorigenesis.
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Affiliation(s)
- Lauren E Tebay
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Holly Robertson
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Stephen T Durant
- AstraZeneca Oncology Innovative Medicines, Bioscience, 33F197 Mereside, Alderley Park, Cheshire SK10 4TG, UK
| | - Steven R Vitale
- Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6160, USA
| | - Trevor M Penning
- Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-6160, USA
| | - Albena T Dinkova-Kostova
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - John D Hayes
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK.
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Kayama Y, Raaz U, Jagger A, Adam M, Schellinger IN, Sakamoto M, Suzuki H, Toyama K, Spin JM, Tsao PS. Diabetic Cardiovascular Disease Induced by Oxidative Stress. Int J Mol Sci 2015; 16:25234-63. [PMID: 26512646 PMCID: PMC4632800 DOI: 10.3390/ijms161025234] [Citation(s) in RCA: 264] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 09/30/2015] [Accepted: 09/30/2015] [Indexed: 01/10/2023] Open
Abstract
Cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes mellitus (DM). DM can lead to multiple cardiovascular complications, including coronary artery disease (CAD), cardiac hypertrophy, and heart failure (HF). HF represents one of the most common causes of death in patients with DM and results from DM-induced CAD and diabetic cardiomyopathy. Oxidative stress is closely associated with the pathogenesis of DM and results from overproduction of reactive oxygen species (ROS). ROS overproduction is associated with hyperglycemia and metabolic disorders, such as impaired antioxidant function in conjunction with impaired antioxidant activity. Long-term exposure to oxidative stress in DM induces chronic inflammation and fibrosis in a range of tissues, leading to formation and progression of disease states in these tissues. Indeed, markers for oxidative stress are overexpressed in patients with DM, suggesting that increased ROS may be primarily responsible for the development of diabetic complications. Therefore, an understanding of the pathophysiological mechanisms mediated by oxidative stress is crucial to the prevention and treatment of diabetes-induced CVD. The current review focuses on the relationship between diabetes-induced CVD and oxidative stress, while highlighting the latest insights into this relationship from findings on diabetic heart and vascular disease.
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Affiliation(s)
- Yosuke Kayama
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Uwe Raaz
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Ann Jagger
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Matti Adam
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Isabel N Schellinger
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Masaya Sakamoto
- Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minatoku, Tokyo 105-0003, Japan.
| | - Hirofumi Suzuki
- Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minatoku, Tokyo 105-0003, Japan.
| | - Kensuke Toyama
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Joshua M Spin
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
| | - Philip S Tsao
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford University, Stanford, CA 94305, USA.
- VA Palo Alto Health Care System, Palo Alto, CA 94304, USA.
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Huang B, Chen CT, Chen CS, Wang YM, Hsieh HJ, Wang DL. Laminar shear flow increases hydrogen sulfide and activates a nitric oxide producing signaling cascade in endothelial cells. Biochem Biophys Res Commun 2015. [PMID: 26212441 DOI: 10.1016/j.bbrc.2015.07.115] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Laminar shear flow triggers a signaling cascade that maintains the integrity of endothelial cells (ECs). Hydrogen sulfide (H2S), a new gasotransmitter is regarded as an upstream regulator of nitric oxide (NO). Whether the H2S-generating enzymes are correlated to the enzymes involved in NO production under shear flow conditions remains unclear as yet. In the present study, the cultured ECs were subjected to a constant shear flow (12 dyn/cm(2)) in a parallel flow chamber system. We investigated the expression of three key enzymes for H2S biosynthesis, cystathionine-γ-lyase (CSE), cystathionine-β-synthase (CBS), and 3-mercapto-sulfurtransferase (3-MST). Shear flow markedly increased the level of 3-MST. Shear flow enhanced the production of H2S was determined by NBD-SCN reagent that can bind to cysteine/homocystein. Exogenous treatment of NaHS that can release gaseous H2S, ECs showed an increase of phosphorylation in Akt(S473), ERK(T202/Y204) and eNOS(S1177). This indicated that H2S can trigger the NO-production signaling cascade. Silencing of CSE, CBS and 3-MST genes by siRNA separately attenuated the phosphorylation levels of Akt(S473) and eNOS(S1177) under shear flow conditions. The particular mode of shear flow increased H2S production. The interplay between H2S and NO-generating enzymes were discussed in the present study.
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Affiliation(s)
- Bin Huang
- Department of Biomedical Science and Environmental Biology, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Center for Biomarkers and Biotech Drugs, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Center for Infectious Disease and Cancer Research, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Chang-Ting Chen
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Chi-Shia Chen
- Department of Biomedical Science and Environmental Biology, College of Life Science, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yun-Ming Wang
- Department of Biological Science and Technology, Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, Hsinchu 30068, Taiwan
| | - Hsyue-Jen Hsieh
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
| | - Danny Ling Wang
- Institute of Medical Science, College of Medicine, Tzu Chi University, Hualien County 97004, Taiwan.
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Kotomin I, Valtink M, Hofmann K, Frenzel A, Morawietz H, Werner C, Funk RHW, Engelmann K. Sutureless fixation of amniotic membrane for therapy of ocular surface disorders. PLoS One 2015; 10:e0125035. [PMID: 25955359 PMCID: PMC4425509 DOI: 10.1371/journal.pone.0125035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 01/17/2015] [Indexed: 11/18/2022] Open
Abstract
Amniotic membrane is applied to the diseased ocular surface to stimulate wound healing and tissue repair, because it releases supportive growth factors and cytokines. These effects fade within about a week after application, necessitating repeated application. Generally, amniotic membrane is fixed with sutures to the ocular surface, but surgical intervention at the inflamed or diseased site can be detrimental. Therefore, we have developed a system for the mounting of amniotic membrane between two rings for application to a diseased ocular surface without surgical intervention (sutureless amniotic membrane transplantation). With this system, AmnioClip, amniotic membrane can be applied like a large contact lens. First prototypes were tested in an experiment on oneself for wearing comfort. The final system was tested on 7 patients in a pilot study. A possible influence of the ring system on the biological effects of amniotic membrane was analyzed by histochemistry and by analyzing the expression of vascular endothelial growth factor-A (VEGF-A), hepatocyte growth factor (HGF), fibroblast growth factor 2 (FGF 2) and pigment epithelium-derived factor (PEDF) from amniotic membranes before and after therapeutic application. The final product, AmnioClip, showed good tolerance and did not impair the biological effects of amniotic membrane. VEGF-A and PEDF mRNA was expressed in amniotic membrane after storage and mounting before transplantation, but was undetectable after a 7-day application period. Consequently, transplantation of amniotic membranes with AmnioClip provides a sutureless and hence improved therapeutic strategy for corneal surface disorders.
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Affiliation(s)
- Ilya Kotomin
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
| | - Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Kai Hofmann
- Deutsche Gesellschaft für Gewebetransplantation, DGFG, Hannover, Germany
| | - Annika Frenzel
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
| | - Henning Morawietz
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
| | - Carsten Werner
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
- Leibniz-Institut für Polymerforschung Dresden e.V., Dresden, Germany
| | - Richard H. W. Funk
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
| | - Katrin Engelmann
- Department of Ophthalmology, Klinikum Chemnitz gGmbH, Chemnitz, Germany
- Deutsche Gesellschaft für Gewebetransplantation, DGFG, Hannover, Germany
- CRTD / DFG-Center for Regenerative Therapies Dresden—Cluster of Excellence, Dresden, Germany
- * E-mail:
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Guo S, Chen X. The human Nox4: gene, structure, physiological function and pathological significance. J Drug Target 2015; 23:888-96. [PMID: 25950600 DOI: 10.3109/1061186x.2015.1036276] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Increased generation of reactive oxygen species (ROS) has been implicated in the pathogenesis of a variety of diseases such as cardiovascular diseases and cancer. NADPH oxidase (Nox), a multicomponent enzyme, has been identified as one of the key sources of ROS. Nox4, one of the seven members of Nox family (Nox1, Nox2, Nox3, Nox4, Nox5, Duox1 and Duox2), has been extensively investigated in recent years. Its unique structures result in the constitutive generation of hydrogen peroxide (H2O2) as the main product. As a key oxygen sensor, Nox4-derived H2O2 plays diverse roles in cell proliferation, migration and death. Increased expression of Nox4 in cancer has been observed, which participates in metastasis, angiogenesis and apoptosis. Expression of Nox4 in endothelial cells actively mediated endothelial activation, dysfunction and injury, which contributes to the development of atherosclerosis, hypertension, cardiac hypertrophy and among others. This article explores the experimental studies related to the gene, structure, physiological function and pathological significance of Nox4. As Nox4 might serve as a potential target for the therapy of cardiovascular diseases and cancer, the Nox4 inhibitor is also discussed in this article.
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Affiliation(s)
- Shuhui Guo
- a State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau , Macao , China
| | - Xiuping Chen
- a State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau , Macao , China
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Langbein H, Hofmann A, Brunssen C, Goettsch W, Morawietz H. Impact of high-fat diet and voluntary running on body weight and endothelial function in LDL receptor knockout mice. ATHEROSCLEROSIS SUPP 2015; 18:59-66. [DOI: 10.1016/j.atherosclerosissup.2015.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Kovac S, Angelova PR, Holmström KM, Zhang Y, Dinkova-Kostova AT, Abramov AY. Nrf2 regulates ROS production by mitochondria and NADPH oxidase. Biochim Biophys Acta Gen Subj 2014; 1850:794-801. [PMID: 25484314 PMCID: PMC4471129 DOI: 10.1016/j.bbagen.2014.11.021] [Citation(s) in RCA: 432] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 11/27/2014] [Accepted: 11/29/2014] [Indexed: 12/30/2022]
Abstract
Background Nuclear factor (erythroid-derived 2) factor 2 (Nrf2) is a crucial transcription factor mediating protection against oxidants. Nrf2 is negatively regulated by cytoplasmic Kelch-like ECH associated protein 1 (Keap1) thereby providing inducible antioxidant defence. Antioxidant properties of Nrf2 are thought to be mainly exerted by stimulating transcription of antioxidant proteins, whereas its effects on ROS production within the cell are uncertain. Methods Live cell imaging and qPCR in brain hippocampal glio-neuronal cultures and explants slice cultures with graded expression of Nrf2, i.e. Nrf2-knockout (Nrf2-KO), wild-type (WT), and Keap1-knockdown (Keap1-KD). Results We here show that ROS production in Nrf2-KO cells and tissues is increased compared to their WT counterparts. Mitochondrial ROS production is regulated by the Keap1–Nrf2 pathway by controlling mitochondrial bioenergetics. Surprisingly, Keap1-KD cells and tissues also showed higher rates of ROS production when compared to WT, although with a smaller magnitude. Analysis of the mRNA expression levels of the two NOX isoforms implicated in brain pathology showed, that NOX2 is dramatically upregulated under conditions of Nrf2 deficiency, whereas NOX4 is upregulated when Nrf2 is constitutively activated (Keap1-KD) to a degree which paralleled the increases in ROS production. Conclusions These observations suggest that the Keap1–Nrf2 pathway regulates both mitochondrial and cytosolic ROS production through NADPH oxidase. General significance Findings supports a key role of the Keap1–Nrf2 pathway in redox homeostasis within the cell. We studied ROS production/NADPH oxidase expression in Nrf2-KO and Keap1-KD cells. ROS production is increased in Nrf2-KO and Keap1-KD neurons when compared to WT. NOX2/NOX4 mRNA in Nrf2-KO and Keap1-KD paralleled these changes.
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Affiliation(s)
- Stjepana Kovac
- UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Department of Neurology, University of Muenster, Muenster, Germany
| | - Plamena R Angelova
- UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Kira M Holmström
- UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
| | - Ying Zhang
- Jacqui Wood Cancer Centre, Division of Cancer Research, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Albena T Dinkova-Kostova
- Departments of Pharmacology and Molecular Sciences and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Departments of Pharmacology and Molecular Sciences and Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Andrey Y Abramov
- UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
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Lv L, Li Y, Deng H, Zhang C, Pu Y, Qian L, Xiao J, Zhao W, Liu Q, Zhang D, Wang Y, Zhang H, He Y, Zhu J. MiR-193a-3p promotes the multi-chemoresistance of bladder cancer by targeting the HOXC9 gene. Cancer Lett 2014; 357:105-113. [PMID: 25444900 DOI: 10.1016/j.canlet.2014.11.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 01/15/2023]
Abstract
Chemoresistance prevents the curative cancer chemotherapy and presents a formidable challenge for both cancer researchers and clinicians. We have previously shown that miR-193a-3p promotes the multi-chemoresistance of bladder cancer cells via repressing its three target genes: SRSF2, PLAU and HIC2. Here, we showed that as a new direct target, the homeobox C9 (HOXC9) gene also executes the promoting effect of miR-193a-3p on the bladder cancer chemoresistance from a systematic study of multi-chemosensitive (5637) and resistant (H-bc) bladder cancer cell lines in both cell culture and tumor-xenograft/nude mice system. Paralleled with the changes in the drug-triggered cell death, the activities of both DNA damage response and oxidative stress pathways were drastically altered by a forced reversal of miR-193a-3p or HOXC9 levels in bladder cancer cells. In addition to a new mechanistic insight, our results provide a set of the essential genes in the miR-193a-3p/HOXC9/DNA damage response/oxidative stress pathway axis as the diagnostic targets for the guided anti-bladder cancer chemotherapy.
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Affiliation(s)
- Lei Lv
- Cancer Epigenetics Program, Anhui Cancer Hospital, Hefei, Anhui 230031, China
| | - Yang Li
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, Anhui 230031, China
| | - Hui Deng
- Cancer Epigenetics Program, Anhui Cancer Hospital, Hefei, Anhui 230031, China
| | - Cheng Zhang
- Department of Urology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Youguang Pu
- Cancer Epigenetics Program, Anhui Cancer Hospital, Hefei, Anhui 230031, China
| | - Liting Qian
- Department of Radiotherapy, Anhui Cancer Hospital, Hefei, Anhui 230031, China
| | - Jun Xiao
- Department of Urology, Anhui Provincial Hospital, Hefei, Anhui, China
| | - Weidong Zhao
- Department of Gynecologic Cancer, Anhui Cancer Hospital, Hefei, Anhui 230031, China
| | - Qi Liu
- School of Life Science and Technology, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China
| | - Daming Zhang
- Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Yingwei Wang
- Department of Pathology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Hongyu Zhang
- Cancer Epigenetics Program, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiaotong University, Shanghai 200032, China
| | - Yinghua He
- Cancer Epigenetics Program, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiaotong University, Shanghai 200032, China
| | - Jingde Zhu
- Cancer Epigenetics Program, Anhui Cancer Hospital, Hefei, Anhui 230031, China; Cancer Epigenetics Program, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiaotong University, Shanghai 200032, China.
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McGill AT. Past and future corollaries of theories on causes of metabolic syndrome and obesity related co-morbidities part 2: a composite unifying theory review of human-specific co-adaptations to brain energy consumption. Arch Public Health 2014; 72:31. [PMID: 25708599 PMCID: PMC4335399 DOI: 10.1186/2049-3258-72-31] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 04/26/2014] [Indexed: 12/13/2022] Open
Abstract
Metabolic syndrome (MetS) predicts type II diabetes mellitus (TIIDM), cardiovascular disease (CVD) and cancer, and their rates have escalated over the last few decades. Obesity related co-morbidities also overlap the concept of the metabolic syndrome (MetS). However, understanding of the syndrome's underlying causes may have been misapprehended. The current paper follows on from a theory review by McGill, A-T in Archives of Public Health, 72: 30. This accompanying paper utilises research on human evolution and new biochemistry to theorise on why MetS and obesity arise and how they affect the population. The basis of this composite unifying theory is that the proportionately large, energy-demanding human brain may have driven co-adaptive mechanisms to provide, or conserve, energy for the brain. A 'dual system' is proposed. 1) The enlarged, complex cortico-limbic-striatal system increases dietary energy by developing strong neural self-reward/motivation pathways for the acquisition of energy dense food, and (2) the nuclear factor-erythroid 2-related factor 2 (NRF2) cellular protection system amplifies antioxidant, antitoxicant and repair activity by employing plant chemicals. In humans who consume a nutritious diet, the NRF2 system has become highly energy efficient. Other relevant human-specific co-adaptations are explored. In order to 'test' this composite unifying theory it is important to show that the hypothesis and sub-theories pertain throughout the whole of human evolution and history up till the current era. Corollaries of the composite unifying theory of MetS are examined with respect to past under-nutrition and malnutrition since agriculture began 10,000 years ago. The effects of man-made pollutants on degenerative change are examined. Projections are then made from current to future patterns on the state of 'insufficient micronutrient and/or unbalanced high energy malnutrition with central obesity and metabolic dysregulation' or 'malnubesity'. Forecasts on human health are made on positive, proactive strategies using the composite unifying theory, and are extended to the wider human ecology of food production. A comparison is made with the outlook for humans if current assumptions and the status quo on causes and treatments are maintained. Areas of further research are outlined. A table of suggestions for possible public health action is included.
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Affiliation(s)
- Anne-Thea McGill
- School of Population Health and Human Nutrition Unit, Faculty of Medicine and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
- B-Med Weight Control Consultancy, Auckland, New Zealand
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McGill AT. Causes of metabolic syndrome and obesity-related co-morbidities Part 1: A composite unifying theory review of human-specific co-adaptations to brain energy consumption. ACTA ACUST UNITED AC 2014; 72:30. [PMID: 25708524 PMCID: PMC4335398 DOI: 10.1186/2049-3258-72-30] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 04/26/2014] [Indexed: 12/30/2022]
Abstract
One line summary Metabolic syndrome and obesity-related co-morbidities are largely explained by co-adaptations to the energy use of the large human brain in the cortico-limbic-striatal and NRF2 systems. The medical, research and general community is unable to effect significantly decreased rates of central obesity and related type II diabetes mellitus (TIIDM), cardiovascular disease (CVD) and cancer. All conditions seem to be linked by the concept of the metabolic syndrome (MetS), but the underlying causes are not known. MetS markers may have been mistaken for causes, thus many treatments are destined to be suboptimal. The current paper aims to critique current paradigms, give explanations for their persistence, and to return to first principles in an attempt to determine and clarify likely causes of MetS and obesity related comorbidities. A wide literature has been mined, study concepts analysed and the basics of human evolution and new biochemistry reviewed. A plausible, multifaceted composite unifying theory is formulated. The basis of the theory is that the proportionately large, energy-demanding human brain may have driven co-adaptive mechanisms to provide, or conserve, energy for the brain. A ‘dual system’ is proposed. 1) The enlarged, complex cortico-limbic-striatal system increases dietary energy by developing strong neural self-reward/motivation pathways for the acquisition of energy dense food, and (2) the nuclear factor-erythroid 2-related factor 2 (NRF2) cellular protection system amplifies antioxidant, antitoxicant and repair activity by employing plant chemicals, becoming highly energy efficient in humans. The still-evolving, complex human cortico-limbic-striatal system generates strong behavioural drives for energy dense food procurement, including motivating agricultural technologies and social system development. Addiction to such foods, leading to neglect of nutritious but less appetizing ‘common or garden’ food, appears to have occurred. Insufficient consumption of food micronutrients prevents optimal human NRF2 function. Inefficient oxidation of excess energy forces central and non-adipose cells to store excess toxic lipid. Oxidative stress and metabolic inflammation, or metaflammation, allow susceptibility to infectious, degenerative atherosclerotic cardiovascular, autoimmune, neurodegenerative and dysplastic diseases. Other relevant human-specific co-adaptations are examined, and encompass the unusual ability to store fat, certain vitamin pathways, the generalised but flexible intestine and microbiota, and slow development and longevity. This theory has significant past and future corollaries, which are explored in a separate article by McGill, A-T, in Archives of Public Health, 72: 31.
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Affiliation(s)
- Anne-Thea McGill
- School of Population Health and Human Nutrition Unit, Faculty of Medicine and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand ; B-Med Weight Control Consultancy, Auckland, New Zealand
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Bai G, Hock TD, Logsdon N, Zhou Y, Thannickal VJ. A far-upstream AP-1/Smad binding box regulates human NOX4 promoter activation by transforming growth factor-β. Gene 2014; 540:62-7. [PMID: 24560583 PMCID: PMC4009368 DOI: 10.1016/j.gene.2014.02.026] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 01/09/2014] [Accepted: 02/18/2014] [Indexed: 01/25/2023]
Abstract
NADPH oxidase 4 (NOX4) is a member of the NADPH oxidase gene family that regulates cellular differentiation, innate immunity and tissue fibrosis. Transforming growth factor-β (TGF-β1) is known to induce expression of NOX4 mRNA in mesenchymal cells. However, the mechanisms of transcriptional regulation of NOX4 are not well understood. In this study, we examined the transcriptional regulation of NOX4 in human lung fibroblasts by TGF-β1. Five promoter-reporter constructs containing DNA fragments of 0.74kb, 1.35kb, 1.84kb, 3.97kb and 4.76kb upstream from the transcriptional start site (TSS) of the human NOX4 gene were generated and their relative responsiveness to TGF-β1 analyzed. TGF-β1-induced NOX4 gene promoter activation requires a region between -3.97kb and -4.76kb. Bioinformatics analysis revealed a 15bp AP-1/Smad binding element in this region. Mutation or deletion of either the AP-1 or the Smad element attenuated TGF-β1 responsiveness of the -4.76kb NOX4 promoter. Furthermore, insertion of this AP-1/Smad box conferred TGF-β1 inducibility to the non-responsive -3.97kb NOX4 promoter construct. Chromatin immunoprecipitation analysis indicated that phospho-Smad3 and cJun associate with this element in a TGF-β1-inducible manner. These results demonstrate that the AP-1/Smad box located between 3.97kb and 4.76kb upstream of the TSS site of the NOX4 promoter is essential for NOX4 gene transcription induced by TGF-β1 in human lung fibroblasts. Our study provides insights into the molecular mechanisms of NOX4 gene expression, informing novel therapeutic approaches to interfere with upregulation of NOX4 in diseases characterized by activation of the TGF-β1/NOX4 pathway.
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Affiliation(s)
- Guangxing Bai
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Thomas D Hock
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Naomi Logsdon
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Yong Zhou
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Victor J Thannickal
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Raaz U, Toh R, Maegdefessel L, Adam M, Nakagami F, Emrich FC, Spin JM, Tsao PS. Hemodynamic regulation of reactive oxygen species: implications for vascular diseases. Antioxid Redox Signal 2014; 20:914-28. [PMID: 23879326 PMCID: PMC3924901 DOI: 10.1089/ars.2013.5507] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Arterial blood vessels functionally and structurally adapt to altering hemodynamic forces in order to accommodate changing needs and to provide stress homeostasis. This ability is achieved at the cellular level by converting mechanical stimulation into biochemical signals (i.e., mechanotransduction). Physiological mechanical stress helps maintain vascular structure and function, whereas pathologic or aberrant stress may impair cellular mechano-signaling, and initiate or augment cellular processes that drive disease. RECENT ADVANCES Reactive oxygen species (ROS) may represent an intriguing class of mechanically regulated second messengers. Chronically enhanced ROS generation may be induced by adverse mechanical stresses, and is associated with a multitude of vascular diseases. Although a causal relationship has clearly been demonstrated in large numbers of animal studies, an effective ROS-modulating therapy still remains to be established by clinical studies. CRITICAL ISSUES AND FUTURE DIRECTIONS This review article focuses on the role of various mechanical forces (in the form of laminar shear stress, oscillatory shear stress, or cyclic stretch) as modulators of ROS-driven signaling, and their subsequent effects on vascular biology and homeostasis, as well as on specific diseases such as arteriosclerosis, hypertension, and abdominal aortic aneurysms. Specifically, it highlights the significance of the various NADPH oxidase (NOX) isoforms as critical ROS generators in the vasculature. Directed targeting of defined components in the complex network of ROS (mechano-)signaling may represent a key for successful translation of experimental findings into clinical practice.
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Affiliation(s)
- Uwe Raaz
- 1 Division of Cardiovascular Medicine, Stanford University School of Medicine , Stanford, California
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Hsieh HJ, Liu CA, Huang B, Tseng AH, Wang DL. Shear-induced endothelial mechanotransduction: the interplay between reactive oxygen species (ROS) and nitric oxide (NO) and the pathophysiological implications. J Biomed Sci 2014; 21:3. [PMID: 24410814 PMCID: PMC3898375 DOI: 10.1186/1423-0127-21-3] [Citation(s) in RCA: 197] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 01/02/2014] [Indexed: 12/26/2022] Open
Abstract
Hemodynamic shear stress, the blood flow-generated frictional force acting on the vascular endothelial cells, is essential for endothelial homeostasis under normal physiological conditions. Mechanosensors on endothelial cells detect shear stress and transduce it into biochemical signals to trigger vascular adaptive responses. Among the various shear-induced signaling molecules, reactive oxygen species (ROS) and nitric oxide (NO) have been implicated in vascular homeostasis and diseases. In this review, we explore the molecular, cellular, and vascular processes arising from shear-induced signaling (mechanotransduction) with emphasis on the roles of ROS and NO, and also discuss the mechanisms that may lead to excessive vascular remodeling and thus drive pathobiologic processes responsible for atherosclerosis. Current evidence suggests that NADPH oxidase is one of main cellular sources of ROS generation in endothelial cells under flow condition. Flow patterns and magnitude of shear determine the amount of ROS produced by endothelial cells, usually an irregular flow pattern (disturbed or oscillatory) producing higher levels of ROS than a regular flow pattern (steady or pulsatile). ROS production is closely linked to NO generation and elevated levels of ROS lead to low NO bioavailability, as is often observed in endothelial cells exposed to irregular flow. The low NO bioavailability is partly caused by the reaction of ROS with NO to form peroxynitrite, a key molecule which may initiate many pro-atherogenic events. This differential production of ROS and RNS (reactive nitrogen species) under various flow patterns and conditions modulates endothelial gene expression and thus results in differential vascular responses. Moreover, ROS/RNS are able to promote specific post-translational modifications in regulatory proteins (including S-glutathionylation, S-nitrosylation and tyrosine nitration), which constitute chemical signals that are relevant in cardiovascular pathophysiology. Overall, the dynamic interplay between local hemodynamic milieu and the resulting oxidative and S-nitrosative modification of regulatory proteins is important for ensuing vascular homeostasis. Based on available evidence, it is proposed that a regular flow pattern produces lower levels of ROS and higher NO bioavailability, creating an anti-atherogenic environment. On the other hand, an irregular flow pattern results in higher levels of ROS and yet lower NO bioavailability, thus triggering pro-atherogenic effects.
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Affiliation(s)
| | | | | | | | - Danny Ling Wang
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan.
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Choy JS, Lu X, Yang J, Zhang ZD, Kassab GS. Endothelial actin depolymerization mediates NADPH oxidase-superoxide production during flow reversal. Am J Physiol Heart Circ Physiol 2013; 306:H69-77. [PMID: 24186098 DOI: 10.1152/ajpheart.00402.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Slow moving blood flow and changes in flow direction, e.g., negative wall shear stress, can cause increased superoxide (O2(·-)) production in vascular endothelial cells. The mechanism by which shear stress increases O2(·-) production, however, is not well established. We tested the hypothesis that actin depolymerization, which occurs during flow reversal, mediates O2(·-) production in vascular endothelial cells via NADPH oxidase, and more specifically, the subunit p47(phox). Using a swine model, we created complete blood flow reversal in one carotid artery, while the contralateral vessel maintained forward blood flow as control. We measured actin depolymerization, NADPH oxidase activity, and reactive oxygen species (ROS) production in the presence of various inhibitors. Flow reversal was found to induce actin depolymerization and a 3.9 ± 1.0-fold increase in ROS production as compared with forward flow. NADPH oxidase activity was 1.4 ± 0.2 times higher in vessel segments subjected to reversed blood flow when measured by a direct enzyme assay. The NADPH oxidase subunits gp91(phox) (Nox2) and p47(phox) content in the vessels remained unchanged after 4 h of flow reversal. In contrast, p47(phox) phosphorylation was increased in vessels with reversed flow. The response caused by reversed flow was reduced by in vivo treatment with jasplakinolide, an actin stabilizer (only a 1.7 ± 0.3-fold increase). Apocynin (an antioxidant) prevented reversed flow-induced ROS production when the animals were treated in vivo. Cytochalasin D mimicked actin depolymerization in vitro and caused a 5.2 ± 3.0-fold increase in ROS production. These findings suggest that actin filaments play an important role in negative shear stress-induced ROS production by potentiating NADPH oxidase activity, and more specifically, the p47(phox) subunit in vascular endothelium.
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Affiliation(s)
- Jenny S Choy
- Department of Biomedical Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Indiana
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Abstract
At least 468 individual genes have been manipulated by molecular methods to study their effects on the initiation, promotion, and progression of atherosclerosis. Most clinicians and many investigators, even in related disciplines, find many of these genes and the related pathways entirely foreign. Medical schools generally do not attempt to incorporate the relevant molecular biology into their curriculum. A number of key signaling pathways are highly relevant to atherogenesis and are presented to provide a context for the gene manipulations summarized herein. The pathways include the following: the insulin receptor (and other receptor tyrosine kinases); Ras and MAPK activation; TNF-α and related family members leading to activation of NF-κB; effects of reactive oxygen species (ROS) on signaling; endothelial adaptations to flow including G protein-coupled receptor (GPCR) and integrin-related signaling; activation of endothelial and other cells by modified lipoproteins; purinergic signaling; control of leukocyte adhesion to endothelium, migration, and further activation; foam cell formation; and macrophage and vascular smooth muscle cell signaling related to proliferation, efferocytosis, and apoptosis. This review is intended primarily as an introduction to these key signaling pathways. They have become the focus of modern atherosclerosis research and will undoubtedly provide a rich resource for future innovation toward intervention and prevention of the number one cause of death in the modern world.
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Affiliation(s)
- Paul N Hopkins
- Cardiovascular Genetics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.
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Roehlecke C, Schumann U, Ader M, Brunssen C, Bramke S, Morawietz H, Funk RHW. Stress reaction in outer segments of photoreceptors after blue light irradiation. PLoS One 2013; 8:e71570. [PMID: 24039718 PMCID: PMC3770596 DOI: 10.1371/journal.pone.0071570] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 07/07/2013] [Indexed: 12/26/2022] Open
Abstract
The retina is prone to oxidative stress from many factors which are also involved in the pathogenesis of degenerative diseases. In this study, we used the application of blue light as a physiological stress factor. The aim of this study was to identify the major source of intracellular ROS that mediates blue light-induced detrimental effects on cells which may lead to cytotoxicity. We hypothesized that outer segments are the major source of blue light induced ROS generation. In photoreceptors, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) enzymes and the recently found respiratory chain complexes may represent a major source for reactive oxygen species (ROS), beside mitochondria and chromophores. Therefore, we investigated this hypothesis and analysed the exact localization of the ROS source in photoreceptors in an organotypic culture system for mouse retinas. Whole eyeball cultures were irradiated with visible blue light (405 nm) with an output power of 1 mW/cm2. Blue light impingement lead to an increase of ROS production (detected by H2DCFDA in live retinal explants), which was particularly strong in the photoreceptor outer segments. Nox-2 and Nox-4 proteins are sources of ROS in blue light irradiated photoreceptors; the Nox inhibitor apocynin decreased ROS stimulated by blue light. Concomitantly, enzyme SOD-1, a member of the antioxidant defense system, indicator molecules of protein oxidation (CML) and lipid oxidation (MDA and 4-HNE) were also increased in the outer segments. Interestingly, outer segments showed a mitochondrial-like membrane potential which was demonstrated using two dyes (JC-1 and TMRE) normally exclusively associated with mitochondria. As in mitochondria, these dyes indicated a decrease of the membrane potential in hypoxic states or cell stress situations. The present study demonstrates that ROS generation and oxidative stress occurs directly in the outer segments of photoreceptors after blue light irradiation.
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Affiliation(s)
- Cora Roehlecke
- Institute of Anatomy, Technische Universität (TU) Dresden, Dresden, Germany
- * E-mail:
| | - Ulrike Schumann
- Institute of Anatomy, Technische Universität (TU) Dresden, Dresden, Germany
| | - Marius Ader
- Center for Regenerative Therapies Dresden (CRTD) DFG – Cluster of Excellence, Biotechnology Center, Dresden, Germany
| | - Coy Brunssen
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
| | - Silvia Bramke
- Institute of Anatomy, Technische Universität (TU) Dresden, Dresden, Germany
| | - Henning Morawietz
- Center for Regenerative Therapies Dresden (CRTD) DFG – Cluster of Excellence, Biotechnology Center, Dresden, Germany
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, TU Dresden, Dresden, Germany
| | - Richard H. W. Funk
- Institute of Anatomy, Technische Universität (TU) Dresden, Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD) DFG – Cluster of Excellence, Biotechnology Center, Dresden, Germany
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Korten S, Brunssen C, Poitz DM, Großklaus S, Brux M, Schnittler HJ, Strasser RH, Bornstein SR, Morawietz H, Goettsch W. Impact of Hey2 and COUP-TFII on genes involved in arteriovenous differentiation in primary human arterial and venous endothelial cells. Basic Res Cardiol 2013; 108:362. [PMID: 23744056 DOI: 10.1007/s00395-013-0362-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 05/10/2013] [Accepted: 05/14/2013] [Indexed: 12/22/2022]
Abstract
Arteries and veins show marked differences in their anatomy, physiology and genetic expression pattern. In this study, we analyzed impact of overexpression or downregulation of arterial marker gene Hey2 and venous marker gene COUP-TFII in human venous and arterial endothelial cells on genes involved in arteriovenous differentiation. Lentiviral overexpression of venous marker gene COUP-TFII in arterial endothelial cells led to downregulation of NICD4, arterial marker gene Hey2 and EphrinB2. Downregulation of Hey2 could be mediated by direct binding of COUP-TFII to Hey2 promoter as shown by ChIP, EMSA and promoter analysis. Downregulation of Hey2 by shRNA causes downregulation of EphrinB2 expression. Overexpression of arterial marker Hey2 in venous endothelial cells did not change expression pattern of COUP-TFII. Downregulation of venous marker gene COUP-TFII in venous endothelial cells resulted in upregulation of VEGF-A, Dll4 and EphrinB2 expression. Our data support an important role of Hey2 and COUP-TFII in arteriovenous differentiation of human endothelial cells.
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Affiliation(s)
- Slobodanka Korten
- Division of Vascular Endothelium and Microcirculation, Department of Medicine III, University Hospital Carl Gustav Carus, University of Technology Dresden, Fetscherstr. 74, 01307, Dresden, Germany
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Guinan AF, Rochfort KD, Fitzpatrick PA, Walsh TG, Pierotti AR, Phelan S, Murphy RP, Cummins PM. Shear stress is a positive regulator of thimet oligopeptidase (EC3.4.24.15) in vascular endothelial cells: consequences for MHC1 levels. Cardiovasc Res 2013; 99:545-54. [DOI: 10.1093/cvr/cvt127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Vázquez-Medina JP, Soñanez-Organis JG, Rodriguez R, Viscarra JA, Nishiyama A, Crocker DE, Ortiz RM. Prolonged fasting activates Nrf2 in post-weaned elephant seals. ACTA ACUST UNITED AC 2013; 216:2870-8. [PMID: 23619404 DOI: 10.1242/jeb.081927] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Elephant seals naturally experience prolonged periods of absolute food and water deprivation (fasting). In humans, rats and mice, prolonged food deprivation activates the renin-angiotensin system (RAS) and increases oxidative damage. In elephant seals, prolonged fasting activates RAS without increasing oxidative damage likely due to an increase in antioxidant defenses. The mechanism leading to the upregulation of antioxidant defenses during prolonged fasting remains elusive. Therefore, we investigated whether prolonged fasting activates the redox-sensitive transcription factor Nrf2, which controls the expression of antioxidant genes, and if such activation is potentially mediated by systemic increases in RAS. Blood and skeletal muscle samples were collected from seals fasting for 1, 3, 5 and 7 weeks. Nrf2 activity and nuclear content increased by 76% and 167% at week 7. Plasma angiotensin II (Ang II) and transforming growth factor β (TGF-β) were 5000% and 250% higher at week 7 than at week 1. Phosphorylation of Smad2, an effector of Ang II and TGF signaling, increased by 120% at week 7 and by 84% in response to intravenously infused Ang II. NADPH oxidase 4 (Nox4) mRNA expression, which is controlled by smad proteins, increased 430% at week 7, while Nox4 protein expression, which can activate Nrf2, was 170% higher at week 7 than at week 1. These results demonstrate that prolonged fasting activates Nrf2 in elephant seals and that RAS stimulation can potentially result in increased Nox4 through Smad phosphorylation. The results also suggest that Nox4 is essential to sustain the hormetic adaptive response to oxidative stress in fasting seals.
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Qian X, Zhao FQ. Interactions of the ubiquitous octamer-binding transcription factor-1 with both the signal transducer and activator of transcription 5 and the glucocorticoid receptor mediate prolactin and glucocorticoid-induced β-casein gene expression in mammary epithelial cells. Int J Biochem Cell Biol 2013; 45:724-35. [PMID: 23313770 DOI: 10.1016/j.biocel.2013.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 11/27/2012] [Accepted: 01/04/2013] [Indexed: 11/30/2022]
Abstract
Regulation of milk protein gene expression by lactogenic hormones (prolactin and glucocorticoids) provides an attractive model for studying the mechanisms by which protein and steroid hormones synergistically regulate gene expression. β-Casein is one of the major milk proteins and its expression in mammary epithelial cells is stimulated by lactogenic hormones. The signal transducer and activator of transcription 5 and glucocorticoid receptor are essential downstream mediators of prolactin and glucocorticoid signaling, respectively. Previous studies have shown that mutating the octamer-binding site of the β-casein gene proximal promoter dramatically reduces the hormonal induction of the promoter activity. However, little is known about the underlying molecular mechanisms. In this report, we show that lactogenic hormones rapidly induce the binding of octamer-binding transcription factor-1 to the β-casein promoter and this induction is not mediated by either increasing the expression of octamer-binding transcription factor-1 or inducing its translocation to the nucleus. Rather, lactogenic hormones induce physical interactions between the octamer-binding transcription factor-1, signal transducer and activator of transcription 5, and glucocorticoid receptor to form a ternary complex, and these interactions enhance or stabilize the binding of these transcription factors to the promoter. Abolishing these interactions significantly reduces the hormonal induction of β-casein gene transcription. Thus, our study indicates that octamer-binding transcription factor-1 may serve as a master regulator that facilitates the DNA binding of both signal transducer and activator of transcription 5 and glucocorticoid receptor in hormone-induced β-casein expression, and defines a novel mechanism of regulation of tissue-specific gene expression by the ubiquitous octamer-binding transcription factor-1.
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Affiliation(s)
- Xi Qian
- Laboratory of Lactation and Metabolic Physiology, Department of Animal Science, University of Vermont, Burlington, VT 05405, USA
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