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Frara N, Giaddui D, Braverman AS, Jawawdeh K, Wu C, Ruggieri, Sr MR, Barbe MF. Mechanisms involved in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox)-derived reactive oxygen species (ROS) modulation of muscle function in human and dog bladders. PLoS One 2023; 18:e0287212. [PMID: 37352265 PMCID: PMC10289437 DOI: 10.1371/journal.pone.0287212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 06/01/2023] [Indexed: 06/25/2023] Open
Abstract
Roles of redox signaling in bladder function is still under investigation. We explored the physiological role of reactive oxygen species (ROS) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) in regulating bladder function in humans and dogs. Mucosa-denuded bladder smooth muscle strips obtained from 7 human organ donors and 4 normal dogs were mounted in muscle baths, and trains of electrical field stimulation (EFS) applied for 20 minutes at 90-second intervals. Subsets of strips were incubated with hydrogen peroxide (H2O2), angiotensin II (Ang II; Nox activator), apocynin (inhibitor of Noxs and ROS scavenger), or ZD7155 (specific inhibitor of angiotensin type 1 (AT1) receptor) for 20 minutes in continued EFS trains. Subsets treated with inhibitors were then treated with H2O2 or Ang II. In human and dog bladders, the ROS, H2O2 (100μM), caused contractions and enhanced EFS-induced contractions. Apocynin (100μM) attenuated EFS-induced strip contractions in both species; subsequent treatment with H2O2 restored strip activity. In human bladders, Ang II (1μM) did not enhance EFS-induced contractions yet caused direct strip contractions. In dog bladders, Ang II enhanced both EFS-induced and direct contractions. Ang II also partially restored EFS-induced contractions attenuated by prior apocynin treatment. In both species, treatment with ZD7155 (10μM) inhibited EFS-induced activity; subsequent treatment with Ang II did not restore strip activity. Collectively, these data provide evidence that ROS can modulate bladder function without exogenous stimuli. Since inflammation is associated with oxidative damage, the effects of Ang II on bladder smooth muscle function may have pathologic implications.
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Affiliation(s)
- Nagat Frara
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Dania Giaddui
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Alan S. Braverman
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Kais Jawawdeh
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Changhao Wu
- Department of Biochemistry and Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Michael R. Ruggieri, Sr
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Mary F. Barbe
- Center for Translational Medicine at the Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania, United States of America
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2
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Meister ML, Najjar RS, Danh JP, Knapp D, Wanders D, Feresin RG. Berry consumption mitigates the hypertensive effects of a high-fat, high-sucrose diet via attenuation of renal and aortic AT 1R expression resulting in improved endothelium-derived NO bioavailability. J Nutr Biochem 2023; 112:109225. [PMID: 36435288 DOI: 10.1016/j.jnutbio.2022.109225] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 10/12/2022] [Accepted: 11/17/2022] [Indexed: 11/25/2022]
Abstract
Dysregulation of the renin-angiotensin system (RAS) is a contributor to high-fat diet-related blood pressure (BP) increases. Deleterious effects of dysregulated RAS result in an overproduction of reactive oxygen species and a decrease in endothelial nitric oxide (NO) bioavailability due to increased NADPH oxidase (NOX) expression. Dietary polyphenols have been shown to mitigate the imbalance in the redox state and protect against endothelial dysfunction induced by a high-fat diet. Thus, we aim to determine whether polyphenol-rich blackberry and raspberry, alone and in combination, attenuate the detrimental effects of a high-fat, high-sucrose (HFHS) diet on the vascular endothelium and kidneys of mice. We show that a HFHS diet increased the expression of renal and aortic angiotensin type 1 receptor (AT1R). Further, NOX1 and NOX4 expression were increased in the kidney contributing to fibrotic damage. In human aortic endothelial cells (HAECs), palmitic acid increased the expression of NOX4, potentially driving oxidative damage in the aorta, as evidenced by increased nitrotyrosine expression. Berries reduced the expression of renal and aortic AT1R, leading to a subsequent decrease in renal NOX expression and reduced aortic oxidative stress evidenced by reduced nitrotyrosine expression. Blackberry and raspberry in combination increased the expression of NRF2 and its downstream proteins in HAECs, thereby reducing the oxidative burden to the endothelium. In combination, blackberry and raspberry also increased serum levels of NO metabolites. These findings indicate that blackberry and raspberry unique polyphenols may act synergistically to favorably modulate the abovementioned pathways and attenuate HFHS diet-induced increases in BP.
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Affiliation(s)
- Maureen L Meister
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA
| | - Rami S Najjar
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA
| | - Jessica P Danh
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA
| | - Denise Knapp
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA
| | - Desiree Wanders
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA
| | - Rafaela G Feresin
- Department of Nutrition, Georgia State University, Atlanta, Georgia, USA.
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3
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Esteves-Monteiro M, Menezes-Pinto D, Ferreira-Duarte M, Dias-Pereira P, Morato M, Duarte-Araújo M. Histomorphometry Changes and Decreased Reactivity to Angiotensin II in the Ileum and Colon of Streptozotocin-Induced Diabetic Rats. Int J Mol Sci 2022; 23:13233. [PMID: 36362021 PMCID: PMC9656372 DOI: 10.3390/ijms232113233] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/19/2022] [Accepted: 10/27/2022] [Indexed: 10/15/2023] Open
Abstract
Diabetes mellitus (DM) is a chronic progressive metabolic disorder associated with several gastrointestinal complications, affecting up to 75% of patients. Knowing that Angiotensin II (AngII) also regulates intestinal contraction, we decided to evaluate changes in ileum and colon histomorphometry and AngII reactivity in a rat model of DM. Streptozotocin (STZ, 55 mg/kg) was administered to induce DM to 24 adult male Wistar rats. Diabetic rats displayed all the characteristic signs of type 1 DM (T1DM) and fecal excretion increased about 4-fold over 14 days, while the excretion of controls remained unaltered. Compared to controls, diabetic ileum and colon presented an increase in both macroscopic (length, perimeter and weight) and microscopic (muscular wall thickness) parameters. Functionally, AngII-induced smooth muscle contraction was lower in diabetic rats, except in the distal colon. These differences in the contractile response to AngII may result from an imbalance between AngII type 1 (antagonized by candesartan, 10 nM) and type 2 receptors activation (antagonized by PD123319, 100 nM). Taken together, these results indicate that an early and refined STZ-induced T1DM rat model already shows structural remodelling of the gut wall and decreased contractile response to AngII, findings that may help to explain diabetic dysmotility.
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Affiliation(s)
- Marisa Esteves-Monteiro
- LAQV-REQUIMTE, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- Department of Immuno-Physiology and Pharmacology, Institute of Biomedical Sciences Abel Salazar, University of Porto (ICBAS-UP), 4050-313 Porto, Portugal
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto (FFUP), 4050-313 Porto, Portugal
| | - Daniela Menezes-Pinto
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto (FFUP), 4050-313 Porto, Portugal
| | - Mariana Ferreira-Duarte
- LAQV-REQUIMTE, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto (FFUP), 4050-313 Porto, Portugal
| | - Patrícia Dias-Pereira
- Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar, University of Porto (ICBAS-UP), 4050-313 Porto, Portugal
| | - Manuela Morato
- LAQV-REQUIMTE, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto (FFUP), 4050-313 Porto, Portugal
| | - Margarida Duarte-Araújo
- LAQV-REQUIMTE, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- Department of Immuno-Physiology and Pharmacology, Institute of Biomedical Sciences Abel Salazar, University of Porto (ICBAS-UP), 4050-313 Porto, Portugal
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4
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Ferreira A, Rivera A, Wohlgemuth JG, Dlott JS, Snyder LM, Alper SL, Romero JR. Dysregulated Erythroid Mg2+ Efflux in Type 2 Diabetes. Front Cell Dev Biol 2022; 10:861644. [PMID: 35445032 PMCID: PMC9013827 DOI: 10.3389/fcell.2022.861644] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/09/2022] [Indexed: 12/23/2022] Open
Abstract
Hyperglycemia is associated with decreased Mg2+ content in red blood cells (RBC), but mechanisms remain unclear. We characterized the regulation of Mg2+ efflux by glucose in ex vivo human RBC. We observed that hemoglobin A1C (HbA1C) values correlated with Na+-dependent Mg2+ efflux (Na+/Mg2+ exchange) and inversely correlated with cellular Mg content. Treatment of cells with 50 mM D-glucose, but not with sorbitol, lowered total cellular Mg (2.2 ± 0.1 to 2.0 ± 0.1 mM, p < 0.01) and enhanced Na+/Mg2+ exchange activity [0.60 ± 0.09 to 1.12 ± 0.09 mmol/1013 cell × h (flux units, FU), p < 0.05]. In contrast, incubation with selective Src family kinase inhibitors PP2 or SU6656 reduced glucose-stimulated exchange activation (p < 0.01). Na+/Mg2+ exchange activity was also higher in RBC from individuals with type 2 diabetes (T2D, 1.19 ± 0.13 FU) than from non-diabetic individuals (0.58 ± 0.05 FU, p < 0.01). Increased Na+/Mg2+ exchange activity in RBC from T2D subjects was associated with lower intracellular Mg content. Similarly increased exchange activity was evident in RBC from the diabetic db/db mouse model as compared to its non-diabetic control (p < 0.03). Extracellular exposure of intact RBC from T2D subjects to recombinant peptidyl-N-glycosidase F (PNGase F) reduced Na+/Mg2+ exchange activity from 0.98 ± 0.14 to 0.59 ± 0.13 FU (p < 0.05) and increased baseline intracellular Mg content (1.8 ± 0.1 mM) to normal values (2.1 ± 0.1 mM, p < 0.05). These data suggest that the reduced RBC Mg content of T2D RBC reflects enhanced RBC Na+/Mg2+ exchange subject to regulation by Src family kinases and by the N-glycosylation state of one or more membrane proteins. The data extend our understanding of dysregulated RBC Mg2+ homeostasis in T2D.
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Affiliation(s)
- Ana Ferreira
- Interdisciplinary Centre of Social Sciences (CICS.NOVA), Faculty of Social Sciences and Humanities (NOVA FCSH), Lisbon, Portugal
| | - Alicia Rivera
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
- *Correspondence: Alicia Rivera,
| | | | | | | | - Seth L. Alper
- Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
| | - Jose R. Romero
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
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Bunaim MK, Kamisah Y, Mohd Mustazil MN, Fadhlullah Zuhair JS, Juliana AH, Muhammad N. Centella asiatica (L.) Urb. Prevents Hypertension and Protects the Heart in Chronic Nitric Oxide Deficiency Rat Model. Front Pharmacol 2021; 12:742562. [PMID: 34925007 PMCID: PMC8678489 DOI: 10.3389/fphar.2021.742562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 11/03/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Hypertension is a major risk factor for cardiovascular disease (CVD), which is the number one cause of global mortality. The potential use of natural products to alleviate high blood pressure has been demonstrated to exert a cardioprotective effect. Centella asiatica (L.) Urb. belongs to the plant family Apiaceae (Umbelliferae). It contains a high amount of triterpenoid and flavonoid that have antioxidant properties and are involved in the renin-angiotensin-aldosterone system which is an important hormonal system for blood pressure regulation. Objective: This study aimed to investigate the effects of C. asiatica ethanolic extract on blood pressure and heart in a hypertensive rat model, which was induced using oral N(G)-nitro-l-arginine methyl ester (l-NAME). Methods: Male Sprague-Dawley rats were divided into five groups and were given different treatments for 8 weeks. Group 1 only received deionized water. Groups 2, 4, and 5 were given l-NAME (40 mg/kg, orally). Groups 4 and 5 concurrently received C. asiatica extract (500 mg/kg, orally) and captopril (5 mg/kg, orally), respectively. Group 3 only received C. asiatica extract (500 mg/kg body weight, orally). Systolic blood pressure (SBP) was measured at weeks 0, 4, and 8, while serum nitric oxide (NO) was measured at weeks 0 and 8. At necropsy, cardiac and aortic malondialdehyde (MDA) contents, cardiac angiotensin-converting enzyme (ACE) activity, and serum level of brain natriuretic peptide (BNP) were measured. Results: After 8 weeks, the administrations of C. asiatica extract and captopril showed significant (p < 0.05) effects on preventing the elevation of SBP, reducing the serum nitric oxide level, as well as increasing the cardiac and aortic MDA content, cardiac ACE activity, and serum brain natriuretic peptide level. Conclusion: C. asiatica extract can prevent the development of hypertension and cardiac damage induced by l-NAME, and these effects were comparable to captopril.
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Affiliation(s)
- Mohd Khairulanwar Bunaim
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.,Department of Biomedical Sciences and Therapeutics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Yusof Kamisah
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Mohd Noor Mohd Mustazil
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | | | - Abdul Hamid Juliana
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Norliza Muhammad
- Department of Pharmacology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
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6
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Cai M, Wang Z, Luu TTT, Zhang D, Finke B, He J, Tay LWR, Di Paolo G, Du G. PLD1 promotes reactive oxygen species production in vascular smooth muscle cells and injury-induced neointima formation. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1867:159062. [PMID: 34610470 DOI: 10.1016/j.bbalip.2021.159062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/28/2021] [Accepted: 08/31/2021] [Indexed: 10/20/2022]
Abstract
Phospholipase D (PLD) generates the signaling lipid phosphatidic acid (PA) and has been known to mediate proliferation signal in vascular smooth muscle cells (VSMCs). However, it remains unclear how PLD contributes to vascular diseases. VSMC proliferation directly contributes to the development and progression of cardiovascular disease, such as atherosclerosis and restenosis after angioplasty. Using the mouse carotid artery ligation model, we find that deletion of Pld1 gene inhibits neointima formation of the injuried blood vessels. PLD1 deficiency reduces the proliferation of VSMCs in both injured artery and primary cultures through the inhibition of ERK1/2 and AKT signals. Immunohistochemical staining of injured artery and flow cytometry analysis of VSMCs shows a reduction of the levels of reactive oxygen species (ROS) in Pld1-/- VSMCs. An increase of intracellular ROS by hydrogen peroxide stimulation restored the reduced activities of ERK and AKT in Pld1-/- VSMCs, whereas a reduction of ROS by N-acetyl-l-cysteine (NAC) scavenger lowered their activity in wild-type VSMCs. These results indicate that PLD1 plays a critical role in neointima, and that PLD1 mediates VSMC proliferation signal through promoting the production of ROS. Therefore, inhibition of PLD1 may be used as a therapeutic approach to suppress neointimal formation in atherosclerosis and restenosis after angioplasty.
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Affiliation(s)
- Ming Cai
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province, China
| | - Ziqing Wang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Thi Thu Trang Luu
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Biochemistry and Cell Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
| | - Dakai Zhang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Brian Finke
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jingquan He
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Li Wei Rachel Tay
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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7
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Abstract
Neurohormones and inflammatory mediators have effects in both the heart and the peripheral vasculature. In patients with heart failure (HF), neurohormonal activation and increased levels of inflammatory mediators promote ventricular remodeling and development of HF, as well as vascular dysfunction and arterial stiffness. These processes may lead to a vicious cycle, whereby arterial stiffness perpetuates further ventricular remodeling leading to exacerbation of symptoms. Although significant advances have been made in the treatment of HF, currently available treatment strategies slow, but do not halt, this cycle. The current treatment for HF patients involves the inhibition of neurohormonal activation, which can reduce morbidity and mortality related to this condition. Beyond benefits associated with neurohormonal blockade, other strategies have focused on inhibition of inflammatory pathways implicated in the pathogenesis of HF. Unfortunately, attempts to target inflammation have not yet been successful to improve prognosis of HF. Further work is required to interrupt key maladaptive mechanisms involved in disease progression.
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8
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Grijalva-Guiza RE, Jiménez-Garduño AM, Hernández LR. Potential Benefits of Flavonoids on the Progression of Atherosclerosis by Their Effect on Vascular Smooth Muscle Excitability. Molecules 2021; 26:3557. [PMID: 34200914 PMCID: PMC8230563 DOI: 10.3390/molecules26123557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/05/2021] [Accepted: 06/06/2021] [Indexed: 12/26/2022] Open
Abstract
Flavonoids are a group of secondary metabolites derived from plant-based foods, and they offer many health benefits in different stages of several diseases. This review will focus on their effects on ion channels expressed in vascular smooth muscle during atherosclerosis. Since ion channels can be regulated by redox potential, it is expected that during the onset of oxidative stress-related diseases, ion channels present changes in their conductive activity, impacting the progression of the disease. A typical oxidative stress-related condition is atherosclerosis, which involves the dysfunction of vascular smooth muscle. We aim to present the state of the art on how redox potential affects vascular smooth muscle ion channel function and summarize if the benefits observed in this disease by using flavonoids involve restoring the ion channel activity.
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Affiliation(s)
- Rosa Edith Grijalva-Guiza
- Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
| | | | - Luis Ricardo Hernández
- Departamento de Ciencias Químico Biológicas, Universidad de las Américas Puebla, San Andrés Cholula 72810, Mexico;
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9
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The Role of the Renal Dopaminergic System and Oxidative Stress in the Pathogenesis of Hypertension. Biomedicines 2021; 9:biomedicines9020139. [PMID: 33535566 PMCID: PMC7912729 DOI: 10.3390/biomedicines9020139] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 01/11/2023] Open
Abstract
The kidney is critical in the long-term regulation of blood pressure. Oxidative stress is one of the many factors that is accountable for the development of hypertension. The five dopamine receptor subtypes (D1R–D5R) have important roles in the regulation of blood pressure through several mechanisms, such as inhibition of oxidative stress. Dopamine receptors, including those expressed in the kidney, reduce oxidative stress by inhibiting the expression or action of receptors that increase oxidative stress. In addition, dopamine receptors stimulate the expression or action of receptors that decrease oxidative stress. This article examines the importance and relationship between the renal dopaminergic system and oxidative stress in the regulation of renal sodium handling and blood pressure. It discusses the current information on renal dopamine receptor-mediated antioxidative network, which includes the production of reactive oxygen species and abnormalities of renal dopamine receptors. Recognizing the mechanisms by which renal dopamine receptors regulate oxidative stress and their degree of influence on the pathogenesis of hypertension would further advance the understanding of the pathophysiology of hypertension.
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10
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Auclair N, Sané AT, Delvin E, Spahis S, Levy E. Phospholipase D as a Potential Modulator of Metabolic Syndrome: Impact of Functional Foods. Antioxid Redox Signal 2021; 34:252-278. [PMID: 32586106 DOI: 10.1089/ars.2020.8081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Significance: Cardiometabolic disorders (CMD) are composed of a plethora of metabolic dysfunctions such as dyslipidemia, nonalcoholic fatty liver disease, insulin resistance, and hypertension. The development of these disorders is highly linked to inflammation and oxidative stress (OxS), two metabolic states closely related to physiological and pathological conditions. Given the drastically rising CMD prevalence, the discovery of new therapeutic targets/novel nutritional approaches is of utmost importance. Recent Advances: The tremendous progress in methods/technologies and animal modeling has allowed the clarification of phospholipase D (PLD) critical roles in multiple cellular processes, whether directly or indirectly via phosphatidic acid, the lipid product mediating signaling functions. In view of its multiple features and implications in various diseases, PLD has emerged as a drug target. Critical Issues: Although insulin stimulates PLD activity and, in turn, PLD regulates insulin signaling, the impact of the two important PLD isoforms on the metabolic syndrome components remains vague. Therefore, after outlining PLD1/PLD2 characteristics and functions, their role in inflammation, OxS, and CMD has been analyzed and critically reported in the present exhaustive review. The influence of functional foods and nutrients in the regulation of PLD has also been examined. Future Directions: Available evidence supports the implication of PLD in CMD, but only few studies emphasize its mechanisms of action and specific regulation by nutraceutical compounds. Therefore, additional investigations are first needed to clarify the functional role of nutraceutics and, second, to elucidate whether targeting PLDs with food compounds represents an appropriate therapeutic strategy to treat CMD. Antioxid. Redox Signal. 34, 252-278.
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Affiliation(s)
- Nickolas Auclair
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.,Department of Pharmacology & Physiology and Université de Montréal, Montreal, Quebec, Canada
| | - Alain T Sané
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Edgard Delvin
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Schohraya Spahis
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.,Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Emile Levy
- Research Center, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.,Department of Pharmacology & Physiology and Université de Montréal, Montreal, Quebec, Canada.,Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
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11
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High Concentrations of Uric Acid and Angiotensin II Act Additively to Produce Endothelial Injury. Mediators Inflamm 2020; 2020:8387654. [PMID: 32565731 PMCID: PMC7261330 DOI: 10.1155/2020/8387654] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 02/22/2020] [Accepted: 03/10/2020] [Indexed: 12/22/2022] Open
Abstract
Renin angiotensin (Ang) system (RAS) activation in metabolic syndrome (MS) patients is associated with elevated uric acid (UA) levels, resulting in endothelial system dysfunction. Our previous study demonstrated that excessive UA could cause endothelial injury through the aldose reductase (AR) pathway. This study is the first to show that a high concentration of Ang II in human umbilical vein endothelial cells (HUVECs) increases reactive oxygen species (ROS) components, including O2·- and H2O2, and further aggravates endothelial system injury induced by high UA (HUA). In a MS/hyperuricemia model, nitric oxide (NO) production was decreased, followed by a decrease in total antioxidant capacity (TAC), and the concentration of the endothelial injury marker von Willebrand factor (vWF) in the serum was increased. Treatment with catalase and polyethylene glycol covalently linked to superoxide dismutase (PEG-SOD) to individually remove H2O2 and O2·- or treatment with the AR inhibitor epalrestat decreased ROS and H2O2, increased NO levels and TAC, and reduced vWF release. Taken together, these data indicate that HUA and Ang II act additively to cause endothelial dysfunction via oxidative stress, and specific elimination of O2·- and H2O2 improves endothelial function. We provide theoretical evidence to prevent or delay endothelial injury caused by metabolic diseases.
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12
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Liang X, Huang R, Huang J, Chen C, Qin F, Liu A, Tang X, Ning T, Nong H. Effect of an aqueous extract of Averrhoa carambola L. on endothelial function in rats with ventricular remodelling. Biomed Pharmacother 2020; 121:109612. [PMID: 31733577 DOI: 10.1016/j.biopha.2019.109612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/25/2019] [Accepted: 10/26/2019] [Indexed: 11/27/2022] Open
Abstract
Ventricular remodelling leads to cardiomyocyte hypertrophy, myocardial fibrosis, endothelial vasoactive substance changes and endothelial dysfunction. Our purpose was to research the effect of an aqueous extract of Averrhoa carambola L. (AEA) on endothelial function in rats with ventricular remodelling induced by isoprenaline. Rats were subjected to injection of isoprenaline and administration of various drugs. Vasoactive substances were measured, and the ventricular remodelling index was detected by the weighing method. Immunohistochemical analysis, pathological examination, Western blot and Masson's trichrome staining were performed. After AEA administration, the levels of transforming growth factor-β (TGF-β), angiotensin II (AngII), inducible NO synthase (iNOS), endothelin-converting enzyme (ECE), and endothelin 1 (ET-1); the ventricular remodelling index; and the collagen volume fraction were decreased, while the levels of total NO synthase (tNOS) and endothelial NO synthase (eNOS) were increased. The pathological examination results showed that apoptosis, fibrosis, necrosis and inflammatory infiltration of myocardial tissue were attenuated by AEA treatment. AEA might alleviate ventricular remodelling in rats by maintaining the balance of vasoactive substances and the function of the vascular endothelium.
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Affiliation(s)
- Xingmei Liang
- Guangxi Medical College, Nanning 530023, Guangxi, P.R. China
| | - Renbin Huang
- Pharmaceutical College, Guangxi Medical University, Nanning 530021, Guangxi, P.R. China
| | - Jianchun Huang
- Pharmaceutical College, Guangxi Medical University, Nanning 530021, Guangxi, P.R. China
| | - Chunxia Chen
- Pharmaceutical College, Guangxi Medical University, Nanning 530021, Guangxi, P.R. China
| | - Feizhang Qin
- Pharmaceutical College, Guangxi Medical University, Nanning 530021, Guangxi, P.R. China
| | - Antao Liu
- Guangxi Medical College, Nanning 530023, Guangxi, P.R. China
| | - Xiaojun Tang
- Guangxi Medical College, Nanning 530023, Guangxi, P.R. China
| | - Tian Ning
- Guangxi Medical College, Nanning 530023, Guangxi, P.R. China
| | - Huiliang Nong
- PhaseI Clinical Center, The First People's Hospital of Nanning, Nanning 530022, Guangxi, P.R. China.
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13
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Knock GA. NADPH oxidase in the vasculature: Expression, regulation and signalling pathways; role in normal cardiovascular physiology and its dysregulation in hypertension. Free Radic Biol Med 2019; 145:385-427. [PMID: 31585207 DOI: 10.1016/j.freeradbiomed.2019.09.029] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/29/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023]
Abstract
The last 20-25 years have seen an explosion of interest in the role of NADPH oxidase (NOX) in cardiovascular function and disease. In vascular smooth muscle and endothelium, NOX generates reactive oxygen species (ROS) that act as second messengers, contributing to the control of normal vascular function. NOX activity is altered in response to a variety of stimuli, including G-protein coupled receptor agonists, growth-factors, perfusion pressure, flow and hypoxia. NOX-derived ROS are involved in smooth muscle constriction, endothelium-dependent relaxation and smooth muscle growth, proliferation and migration, thus contributing to the fine-tuning of blood flow, arterial wall thickness and vascular resistance. Through reversible oxidative modification of target proteins, ROS regulate the activity of protein tyrosine phosphatases, kinases, G proteins, ion channels, cytoskeletal proteins and transcription factors. There is now considerable, but somewhat contradictory evidence that NOX contributes to the pathogenesis of hypertension through oxidative stress. Specific NOX isoforms have been implicated in endothelial dysfunction, hyper-contractility and vascular remodelling in various animal models of hypertension, pulmonary hypertension and pulmonary arterial hypertension, but also have potential protective effects, particularly NOX4. This review explores the multiplicity of NOX function in the healthy vasculature and the evidence for and against targeting NOX for antihypertensive therapy.
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Affiliation(s)
- Greg A Knock
- Dpt. of Inflammation Biology, School of Immunology & Microbial Sciences, Faculty of Life Sciences & Medicine, King's College London, UK.
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14
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NADPH oxidases and oxidase crosstalk in cardiovascular diseases: novel therapeutic targets. Nat Rev Cardiol 2019; 17:170-194. [PMID: 31591535 DOI: 10.1038/s41569-019-0260-8] [Citation(s) in RCA: 288] [Impact Index Per Article: 57.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/19/2019] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS)-dependent production of ROS underlies sustained oxidative stress, which has been implicated in the pathogenesis of cardiovascular diseases such as hypertension, aortic aneurysm, hypercholesterolaemia, atherosclerosis, diabetic vascular complications, cardiac ischaemia-reperfusion injury, myocardial infarction, heart failure and cardiac arrhythmias. Interactions between different oxidases or oxidase systems have been intensively investigated for their roles in inducing sustained oxidative stress. In this Review, we discuss the latest data on the pathobiology of each oxidase component, the complex crosstalk between different oxidase components and the consequences of this crosstalk in mediating cardiovascular disease processes, focusing on the central role of particular NADPH oxidase (NOX) isoforms that are activated in specific cardiovascular diseases. An improved understanding of these mechanisms might facilitate the development of novel therapeutic agents targeting these oxidase systems and their interactions, which could be effective in the prevention and treatment of cardiovascular disorders.
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15
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Hydration Status and Cardiovascular Function. Nutrients 2019; 11:nu11081866. [PMID: 31405195 PMCID: PMC6723555 DOI: 10.3390/nu11081866] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 07/30/2019] [Accepted: 08/08/2019] [Indexed: 02/07/2023] Open
Abstract
Hypohydration, defined as a state of low body water, increases thirst sensations, arginine vasopressin release, and elicits renin–angiotensin–aldosterone system activation to replenish intra- and extra-cellular fluid stores. Hypohydration impairs mental and physical performance, but new evidence suggests hypohydration may also have deleterious effects on cardiovascular health. This is alarming because cardiovascular disease is the leading cause of death in the United States. Observational studies have linked habitual low water intake with increased future risk for adverse cardiovascular events. While it is currently unclear how chronic reductions in water intake may predispose individuals to greater future risk for adverse cardiovascular events, there is evidence that acute hypohydration impairs vascular function and blood pressure (BP) regulation. Specifically, acute hypohydration may reduce endothelial function, increase sympathetic nervous system activity, and worsen orthostatic tolerance. Therefore, the purpose of this review is to present the currently available evidence linking acute hypohydration with altered vascular function and BP regulation.
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16
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Mohamed R, Janke R, Guo W, Cao Y, Zhou Y, Zheng W, Babaahmadi-Rezaei H, Xu S, Kamato D, Little PJ. GPCR transactivation signalling in vascular smooth muscle cells: role of NADPH oxidases and reactive oxygen species. VASCULAR BIOLOGY (BRISTOL, ENGLAND) 2019; 1:R1-R11. [PMID: 32923966 PMCID: PMC7439842 DOI: 10.1530/vb-18-0004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Accepted: 07/23/2019] [Indexed: 02/02/2023]
Abstract
The discovery and extension of G-protein-coupled receptor (GPCR) transactivation-dependent signalling has enormously broadened the GPCR signalling paradigm. GPCRs can transactivate protein tyrosine kinase receptors (PTKRs) and serine/threonine kinase receptors (S/TKRs), notably the epidermal growth factor receptor (EGFR) and transforming growth factor-β type 1 receptor (TGFBR1), respectively. Initial comprehensive mechanistic studies suggest that these two transactivation pathways are distinct. Currently, there is a focus on GPCR inhibitors as drug targets, and they have proven to be efficacious in vascular diseases. With the broadening of GPCR transactivation signalling, it is therefore important from a therapeutic perspective to find a common transactivation pathway of EGFR and TGFBR1 that can be targeted to inhibit complex pathologies activated by the combined action of these receptors. Reactive oxygen species (ROS) are highly reactive molecules and they act as second messengers, thus modulating cellular signal transduction pathways. ROS are involved in different mechanisms of GPCR transactivation of EGFR. However, the role of ROS in GPCR transactivation of TGFBR1 has not yet been studied. In this review, we will discuss the involvement of ROS in GPCR transactivation-dependent signalling.
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Affiliation(s)
- Raafat Mohamed
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
- Department of Basic Sciences, College of Dentistry, University of Mosul, Mosul, Iraq
| | - Reearna Janke
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Wanru Guo
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Yingnan Cao
- Department of Pharmacy, Xinhua College of Sun Yat-sen University, Guangzhou, China
| | - Ying Zhou
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Wenhua Zheng
- Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Hossein Babaahmadi-Rezaei
- Department of Clinical Biochemistry, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Atherosclerosis Research Center, Ahvaz, Iran
| | - Suowen Xu
- Department of Medicine, Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Danielle Kamato
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
- Department of Pharmacy, Xinhua College of Sun Yat-sen University, Guangzhou, China
| | - Peter J Little
- School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Woolloongabba, Queensland, Australia
- Department of Pharmacy, Xinhua College of Sun Yat-sen University, Guangzhou, China
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17
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Touyz RM, Alves-Lopes R, Rios FJ, Camargo LL, Anagnostopoulou A, Arner A, Montezano AC. Vascular smooth muscle contraction in hypertension. Cardiovasc Res 2019; 114:529-539. [PMID: 29394331 PMCID: PMC5852517 DOI: 10.1093/cvr/cvy023] [Citation(s) in RCA: 352] [Impact Index Per Article: 70.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 01/30/2018] [Indexed: 12/19/2022] Open
Abstract
Hypertension is a major risk factor for many common chronic diseases, such as heart failure, myocardial infarction, stroke, vascular dementia, and chronic kidney disease. Pathophysiological mechanisms contributing to the development of hypertension include increased vascular resistance, determined in large part by reduced vascular diameter due to increased vascular contraction and arterial remodelling. These processes are regulated by complex-interacting systems such as the renin-angiotensin-aldosterone system, sympathetic nervous system, immune activation, and oxidative stress, which influence vascular smooth muscle function. Vascular smooth muscle cells are highly plastic and in pathological conditions undergo phenotypic changes from a contractile to a proliferative state. Vascular smooth muscle contraction is triggered by an increase in intracellular free calcium concentration ([Ca2+]i), promoting actin–myosin cross-bridge formation. Growing evidence indicates that contraction is also regulated by calcium-independent mechanisms involving RhoA-Rho kinase, protein Kinase C and mitogen-activated protein kinase signalling, reactive oxygen species, and reorganization of the actin cytoskeleton. Activation of immune/inflammatory pathways and non-coding RNAs are also emerging as important regulators of vascular function. Vascular smooth muscle cell [Ca2+]i not only determines the contractile state but also influences activity of many calcium-dependent transcription factors and proteins thereby impacting the cellular phenotype and function. Perturbations in vascular smooth muscle cell signalling and altered function influence vascular reactivity and tone, important determinants of vascular resistance and blood pressure. Here, we discuss mechanisms regulating vascular reactivity and contraction in physiological and pathophysiological conditions and highlight some new advances in the field, focusing specifically on hypertension.
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Affiliation(s)
- Rhian M Touyz
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Rheure Alves-Lopes
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Francisco J Rios
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Livia L Camargo
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Aikaterini Anagnostopoulou
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
| | - Anders Arner
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Augusto C Montezano
- BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, 126 University Place, Glasgow G12 8TA, UK
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18
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Wang Z, Cai M, Tay LWR, Zhang F, Wu P, Huynh A, Cao X, Di Paolo G, Peng J, Milewicz DM, Du G. Phosphatidic acid generated by PLD2 promotes the plasma membrane recruitment of IQGAP1 and neointima formation. FASEB J 2019; 33:6713-6725. [PMID: 30811216 DOI: 10.1096/fj.201800390rr] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Very little is known about how lipid signaling regulates intima hyperplasia after vascular injury. Herein, we report that deletion and pharmacological inhibition of phospholipase D (PLD)2, which generates the signaling lipid phosphatidic acid (PA), reduced neointimal formation in the mouse carotid artery ligation model. PLD2 deficiency inhibits migration of vascular smooth muscle cells (VSMCs) into the intima in mice as well as migration and formation of membrane ruffles in primary VSMCs. PA specifically binds to the IQ motif-containing guanosine triphosphatase-activating protein 1 (IQGAP1) scaffold protein. The binding between PA and IQGAP is required for the plasma membrane recruitment of IQGAP1. Similar to PLD2 inhibition, knockdown of IQGAP1 blocks ruffle formation and migration in VSMCs, which are rescued by expression of the exogenous IQGAP1 but not the PA binding-deficient mutant. These data reveal that the PLD2-PA-IQGAP1 pathway plays an important role in VSMC migration and injury-induced vascular remodeling, and implicate PLD2 as a candidate target for therapeutic interventions.-Wang, Z., Cai, M., Tay, L. W. R., Zhang, F., Wu, P., Huynh, A., Cao, X., Di Paolo, G., Peng, J., Milewicz, D. M., Du, G. Phosphatidic acid generated by PLD2 promotes the plasma membrane recruitment of IQGAP1 and neointima formation.
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Affiliation(s)
- Ziqing Wang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Ming Cai
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA.,Department of Gastrointestinal Surgery, Union Hospital-Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Wei Rachel Tay
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Feng Zhang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Ping Wu
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Anh Huynh
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Xiumei Cao
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, USA
| | - Junmin Peng
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.,Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA; and
| | - Dianna M Milewicz
- Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, Texas, USA
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19
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Masi S, Uliana M, Virdis A. Angiotensin II and vascular damage in hypertension: Role of oxidative stress and sympathetic activation. Vascul Pharmacol 2019; 115:13-17. [PMID: 30707954 DOI: 10.1016/j.vph.2019.01.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/20/2019] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) are oxygen derivates and play an active role in vascular biology. These compounds are generated within the vascular wall, at the level of endothelial and vascular smooth muscle cells, as well as by adventitial fibroblasts. Physiologically, ROS generation is counteracted effectively by the rate of elimination. In hypertension, a ROS excess occurs, which is not counterbalanced by the endogenous antioxidant mechanisms, leading to a state of oxidative stress. Angiotensin II, the active peptide of the renin-angiotensin-system (RAS), is a significant stimulus for ROS generation within the vasculature. It was also documented that at the level of subfornical cerebral regions an inappropriate RAS stimulation may lead to an increased vascular sympathetic activity. More recently, in conditions of fetal undernutrition, it was also proposed an increased vascular sympathetic activity secondary to inappropriate RAS activation, leading to the development of hypertension in adult life. The present review will discuss the complex interaction between RAS activation, vascular ROS generation and increased sympathetic outflow in hypertension.
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Affiliation(s)
- Stefano Masi
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - Monica Uliana
- Internal Medicine 4, University Hospital of Pisa, Italy
| | - Agostino Virdis
- Department of Clinical and Experimental Medicine, University of Pisa, Italy.
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20
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BCL6 Attenuates Proliferation and Oxidative Stress of Vascular Smooth Muscle Cells in Hypertension. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:5018410. [PMID: 30805081 PMCID: PMC6362478 DOI: 10.1155/2019/5018410] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 11/26/2018] [Indexed: 12/12/2022]
Abstract
Proliferation and oxidative stress of vascular smooth muscle cells (VSMCs) contribute to vascular remodeling in hypertension and several major vascular diseases. B-cell lymphoma 6 (BCL6) functions as a transcriptional repressor. The present study is designed to determine the roles of BCL6 in VSMC proliferation and oxidative stress and underlying mechanism. Angiotensin (Ang) II was used to induce VSMC proliferation and oxidative stress in human VSMCs. Effects of BCL6 overexpression and knockdown were, respectively, investigated in Ang II-treated human VSMCs. Therapeutical effects of BCL6 overexpression on vascular remodeling, oxidative stress, and proliferation were determined in the aorta of spontaneously hypertensive rats (SHR). Ang II reduced BCL6 expression in human VSMCs. BCL6 overexpression attenuated while BCL6 knockdown enhanced the Ang II-induced upregulation of NADPH oxidase 4 (NOX4), production of reactive oxygen species (ROS), and proliferation of VSMCs. BCL6 expression was downregulated in SHR. BCL6 overexpression in SHR reduced NOX4 expression, ROS production, and proliferation of the aortic media of SHR. Moreover, BCL6 overexpression attenuated vascular remodeling and hypertension in SHR. However, BCL6 overexpression had no significant effects on NOX2 expression in human VSMCs or in SHR. We conclude that BCL6 attenuates proliferation and oxidative stress of VSMCs in hypertension.
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21
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Interplay between the renin-angiotensin system, the canonical WNT/β-catenin pathway and PPARγ in hypertension. Curr Hypertens Rep 2018; 20:62. [PMID: 29884931 DOI: 10.1007/s11906-018-0860-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE OF REVIEW Heterogeneous causes can determinate hypertension. RECENT FINDINGS The renin-angiotensin system (RAS) has a major role in the pathophysiology of blood pressure. Angiotensin II and aldosterone are overexpressed during hypertension and lead to hypertension development and its cardiovascular complications. In several tissues, the overactivation of the canonical WNT/β-catenin pathway leads to inactivation of peroxisome proliferator-activated receptor gamma (PPARγ), while PPARγ stimulation induces a decrease of the canonical WNT/β-catenin pathway. In hypertension, the WNT/β-catenin pathway is upregulated, whereas PPARγ is decreased. The WNT/β-catenin pathway and RAS regulate positively each other during hypertension, whereas PPARγ agonists can decrease the expression of both the WNT/β-catenin pathway and RAS. We focus this review on the hypothesis of an opposite interplay between PPARγ and both the canonical WNT/β-catenin pathway and RAS in regulating the molecular mechanism underlying hypertension. The interactions between PPARγ and the canonical WNT/β-catenin pathway through the regulation of the renin-angiotensin system in hypertension may be an interesting way to better understand the actions and the effects of PPARγ agonists as antihypertensive drugs.
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22
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Vallée A, Lecarpentier Y, Guillevin R, Vallée JN. Demyelination in Multiple Sclerosis: Reprogramming Energy Metabolism and Potential PPARγ Agonist Treatment Approaches. Int J Mol Sci 2018; 19:ijms19041212. [PMID: 29659554 PMCID: PMC5979570 DOI: 10.3390/ijms19041212] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 04/09/2018] [Accepted: 04/11/2018] [Indexed: 12/20/2022] Open
Abstract
Demyelination in multiple sclerosis (MS) cells is the site of several energy metabolic abnormalities driven by dysregulation between the opposed interplay of peroxisome proliferator-activated receptor γ (PPARγ) and WNT/β-catenin pathways. We focus our review on the opposing interactions observed in demyelinating processes in MS between the canonical WNT/β-catenin pathway and PPARγ and their reprogramming energy metabolism implications. Demyelination in MS is associated with chronic inflammation, which is itself associated with the release of cytokines by CD4+ Th17 cells, and downregulation of PPARγ expression leading to the upregulation of the WNT/β-catenin pathway. Upregulation of WNT/β-catenin signaling induces activation of glycolytic enzymes that modify their energy metabolic behavior. Then, in MS cells, a large portion of cytosolic pyruvate is converted into lactate. This phenomenon is called the Warburg effect, despite the availability of oxygen. The Warburg effect is the shift of an energy transfer production from mitochondrial oxidative phosphorylation to aerobic glycolysis. Lactate production is correlated with increased WNT/β-catenin signaling and demyelinating processes by inducing dysfunction of CD4+ T cells leading to axonal and neuronal damage. In MS, downregulation of PPARγ decreases insulin sensitivity and increases neuroinflammation. PPARγ agonists inhibit Th17 differentiation in CD4+ T cells and then diminish release of cytokines. In MS, abnormalities in the regulation of circadian rhythms stimulate the WNT pathway to initiate the demyelination process. Moreover, PPARγ contributes to the regulation of some key circadian genes. Thus, PPARγ agonists interfere with reprogramming energy metabolism by directly inhibiting the WNT/β-catenin pathway and circadian rhythms and could appear as promising treatments in MS due to these interactions.
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Affiliation(s)
- Alexandre Vallée
- Délégation à la Recherche Clinique et à l'Innovation (DRCI), Hôpital Foch, 92150 Suresnes, France.
| | - Yves Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), 77100 Meaux, France.
| | - Rémy Guillevin
- Data Analysis and Computations Through Imaging Modeling-Mathématiques (DACTIM), Unité mixte de recherche (UMR), Centre National de la Recherche Scientifique (CNRS) 7348 (Laboratoire de Mathématiques et Application), University of Poitiers, Centre Hospitalier Universitaire (CHU) de Poitiers, 86000 Poitiers, France.
| | - Jean-Noël Vallée
- Centre Hospitalier Universitaire (CHU) Amiens Picardie, University of Picardie Jules Verne (UPJV), 80000 Amiens, France.
- LMA (Laboratoire de Mathématiques et Applications), Unité mixte de recherche (UMR), Centre National de la Recherche Scientifique (CNRS) 7348, Université de Poitiers, 86000 Poitiers, France.
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23
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Lukaszewicz KM, Paudyal MP, Falck JR, Lombard JH. Role of vascular reactive oxygen species in regulating cytochrome P450-4A enzyme expression in Dahl salt-sensitive rats. Microcirculation 2018; 23:540-548. [PMID: 27537772 DOI: 10.1111/micc.12304] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 08/15/2016] [Indexed: 01/09/2023]
Abstract
OBJECTIVE The potential contribution of CYP4A enzymes to endothelial dysfunction in Dahl salt-sensitive rats was determined by comparison to SS-5BN consomic rats having chromosome 5 carrying CYP4A alleles from the BN rat introgressed into the SS genetic background. METHODS The following experiments were performed in cerebral arteries from HS-fed SS and SS-5BN rats ± the SOD inhibitor DETC and/or the superoxide scavenger Tempol: (i) endothelial function was determined via video microscopy ± acute addition of the CYP4A inhibitor DDMS or Tempol; (ii) vascular oxidative stress was assessed with DHE fluorescence ± acute addition of DDMS, l-NAME, or PEG-SOD; and (iii) CYP4A protein levels were compared by western blotting. RESULTS In DETC-treated SS-5BN and HS-fed SS rats, (i) DDMS or Tempol ameliorated vascular dysfunction, (ii) DDMS reduced vascular oxidative stress to control levels, (iii) chronic Tempol treatment reduced vascular CYP4A protein expression, and (iv) combined treatment with Tempol and l-NAME prevented the reduction in CYP4A protein expression in MCA of HS-fed SS rats. CONCLUSION The CYP4A pathway plays a role in vascular dysfunction in SS rats and there appears to be a direct role of reduced NO availability due to salt-induced oxidant stress in upregulating CYP4A enzyme expression.
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Affiliation(s)
| | - Mahesh P Paudyal
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John R Falck
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Julian H Lombard
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA.
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24
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Thatcher SE. A Brief Introduction into the Renin-Angiotensin-Aldosterone System: New and Old Techniques. Methods Mol Biol 2017; 1614:1-19. [PMID: 28500591 DOI: 10.1007/978-1-4939-7030-8_1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The renin-angiotensin-aldosterone system (RAAS) is a complex system of enzymes, receptors, and peptides that help to control blood pressure and fluid homeostasis. Techniques in studying the RAAS can be difficult due to such factors as peptide/enzyme stability and receptor localization. This paper gives a brief account of the different components of the RAAS and current methods in measuring each component. There is also a discussion of different methods in measuring stem and immune cells by flow cytometry, hypertension, atherosclerosis, oxidative stress, energy balance, and other RAAS-activated phenotypes. While studies on the RAAS have been performed for over 100 years, new techniques have allowed scientists to come up with new insights into this system. These techniques are detailed in this Methods in Molecular Biology Series and give students new to studying the RAAS the proper controls and technical details needed to perform each procedure.
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Affiliation(s)
- Sean E Thatcher
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Charles T. Wethington Bldg, 593, 900 South Limestone Street, Lexington, KY, 40536, USA.
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25
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Gowrisankar YV, Clark MA. Angiotensin II induces interleukin-6 expression in astrocytes: Role of reactive oxygen species and NF-κB. Mol Cell Endocrinol 2016; 437:130-141. [PMID: 27539920 DOI: 10.1016/j.mce.2016.08.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/21/2016] [Accepted: 08/08/2016] [Indexed: 02/07/2023]
Abstract
Previously, we showed that the bio-peptide angiotensin (Ang) II induces interleukin-6 (IL-6) in cultured astrocytes; however, the mechanism(s) involved in this effect were unknown. In the current study, we determined in brainstem and cerebellum astrocytes from the spontaneously hypertensive rat (SHR), the effect of Ang II to induce IL-6 as well as reactive oxygen species (ROS) generation. Results from this study showed that Ang II significantly induced the differential expression of IL-6 mRNA and protein levels in astrocytes from both regions of Wistar and SHRs. There were differences in the ability of Ang II to induce IL-6 mRNA and protein levels, but these differences were not apparent at all time points examined. Ang II also induced ROS generation, but there were no significant differences between ROS generation in SHR samples as compared to the Wistar samples. Ang II-induced IL-6 levels were mediated via the AT1/Nuclear Factor Kappa beta/ROS pathway. Overall, our findings suggest that there may be dysregulation in IL-6 production from astrocytes, contributing to differences observed in SHRs versus its normotensive control. Elucidating the mechanisms involved in Ang II pro-inflammatory effects in the central nervous system may lead to the development of novel therapeutic strategies that can be harnessed not just to treat hypertension, but other Ang II-mediated diseases as well.
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Affiliation(s)
- Yugandhar V Gowrisankar
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, FL 33328, United States
| | - Michelle A Clark
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, 3200 South University Drive, Fort Lauderdale, FL 33328, United States.
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Ardanaz N, Pagano PJ. Hydrogen Peroxide as a Paracrine Vascular Mediator: Regulation and Signaling Leading to Dysfunction. Exp Biol Med (Maywood) 2016; 231:237-51. [PMID: 16514169 DOI: 10.1177/153537020623100302] [Citation(s) in RCA: 166] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Numerous studies have demonstrated the ability of a variety of vascular cells, including endothelial cells, smooth muscle cells, and fibroblasts, to produce reactive oxygen species (ROS). Until recently, major emphasis was placed on the production of superoxide anion (O2–) in the vasculature as a result of its ability to directly attenuate the biological activity of endothelium-derived nitric oxide (NO). The short half-life and radius of diffusion of O2– drastically limit the role of this ROS as an important paracrine hormone in vascular biology. On the contrary, in recent years, the O2– metabolite hydrogen peroxide (H2O2) has increasingly been viewed as an important cellular signaling agent in its own right, capable of modulating both contractile and growth-promoting pathways with more far-reaching effects. In this review, we will assess the vascular production of H2O2, its regulation by endogenous scavenger systems, and its ability to activate a variety of vascular signaling pathways, thereby leading to vascular contraction and growth. This discussion will include the ability of H2O2 to (i) Initiate calcium flux as well as (ii) stimulate pathways leading to sensitization of contractile elements to calcium. The latter involves a variety of protein kinases that have also been strongly implicated in vascular hypertrophy. Previous Intensive study has emphasized the ability of NADPH oxidase-derived O2– and H2O2 to activate these pathways in cultured smooth muscle cells. However, growing evidence indicates a considerably more complex array of unique oxidase systems in the endothelium, media, and adventitia that appear to participate in these deleterious effects in a sequential and temporal manner. Taken together, these findings seem consistent with a paracrine effect of H2O2 across the vascular wall.
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Affiliation(s)
- Noelia Ardanaz
- Hypertension and Vascular Research Division, RM 7044, E&R Building, Henry Ford Hospital, 2799 West Grand Boulevard, Detroit, MI 48202-2689, USA
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KVANDOVÁ M, MAJZÚNOVÁ M, DOVINOVÁ I. The Role of PPARγ in Cardiovascular Diseases. Physiol Res 2016; 65:S343-S363. [DOI: 10.33549/physiolres.933439] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The peroxisome proliferator-activated receptors (PPAR) belong to the nuclear superfamily of ligand-activated transcription factors. PPARγ acts as a nutrient sensor that regulates several homeostatic functions. Its disruption can lead to vascular pathologies, disorders of fatty acid/lipid metabolism and insulin resistance. PPARγ can modulate several signaling pathways connected with blood pressure regulation. Firstly, it affects the insulin signaling pathway and endothelial dysfunction by modulation of expression and/or phosphorylation of signaling molecules through the PI3K/Akt/eNOS or MAPK/ET-1 pathways. Secondly, it can modulate gene expression of the renin- angiotensin system – cascade proteins, which potentially slow down the progression of atherosclerosis and hypertension. Thirdly, it can modulate oxidative stress response either directly through PPAR or indirectly through Nrf2 activation. In this context, activation and functioning of PPARγ is very important in the regulation of several disorders such as diabetes mellitus, hypertension and/or metabolic syndrome.
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Affiliation(s)
| | | | - I. DOVINOVÁ
- Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovakia
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Maiolino G, Azzolini M, Rossi GP, Davis PA, Calò LA. Bartter/Gitelman syndromes as a model to study systemic oxidative stress in humans. Free Radic Biol Med 2015; 88:51-8. [PMID: 25770663 DOI: 10.1016/j.freeradbiomed.2015.02.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/24/2015] [Accepted: 02/26/2015] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) are intermediates in reduction-oxidation reactions that begin with the addition of one electron to molecular oxygen, generating the primary ROS superoxide, which in turn interacts with other molecules to produce secondary ROS, such as hydrogen peroxide, hydroxyl radical, and peroxynitrite. ROS are continuously produced during metabolic processes and are deemed to play an important role in cardiovascular diseases, namely, myocardial hypertrophy and fibrosis and atherosclerosis, via oxidative damage of lipids, proteins, and deoxyribonucleic acid. Angiotensin II (Ang II) is a potent vasoactive agent that also exerts mitogenic, proinflammatory, and profibrotic effects through several signaling pathways, in part involving ROS, particularly superoxide and hydrogen peroxide. Moreover, Ang II stimulates NADPH oxidases, leading to higher ROS generation and oxidative stress. Bartter/Gitelman syndrome patients, despite elevated plasma renin activity, Ang II, and aldosterone levels, exhibit reduced peripheral resistance, normal/low blood pressure, and blunted pressor effect of vasoconstrictors. In addition, notwithstanding the activation of the renin-angiotensin system and the increased plasma levels of Ang II, these patients display decreased production of ROS, reduced oxidative stress, and increased antioxidant defenses. In fact, Bartter/Gitelman syndrome patients are characterized by reduced levels of p22(phox) gene expression and undetectable plasma peroxynitrite levels, while showing increased plasma antioxidant power and expression of antioxidant enzymes, such as heme oxygenase-1. In conclusion, multifarious data suggest that Bartter and Gitelman syndrome patients are a model of low oxidative stress and high antioxidant defenses. The contribution offered by the study of these syndromes in elucidating the molecular mechanisms underlying this favorable status could offer chances for new therapeutic targets in disease characterized by high levels of reactive oxygen species.
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Affiliation(s)
- Giuseppe Maiolino
- Nephrology and Hypertension Clinic, Department of Medicine, University of Padova, 35126 Padova, Italy
| | - Matteo Azzolini
- Nephrology and Hypertension Clinic, Department of Medicine, University of Padova, 35126 Padova, Italy
| | - Gian Paolo Rossi
- Nephrology and Hypertension Clinic, Department of Medicine, University of Padova, 35126 Padova, Italy
| | - Paul A Davis
- Department of Nutrition, University of California at Davis, Davis, CA 95616, USA
| | - Lorenzo A Calò
- Nephrology and Hypertension Clinic, Department of Medicine, University of Padova, 35126 Padova, Italy.
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Ghantous CM, Kobeissy FH, Soudani N, Rahman FA, Al-Hariri M, Itani HA, Sabra R, Zeidan A. Mechanical stretch-induced vascular hypertrophy occurs through modulation of leptin synthesis-mediated ROS formation and GATA-4 nuclear translocation. Front Pharmacol 2015; 6:240. [PMID: 26557089 PMCID: PMC4615939 DOI: 10.3389/fphar.2015.00240] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/05/2015] [Indexed: 12/11/2022] Open
Abstract
Background: Obesity and hypertension are associated with increased leptin production contributing to cardiovascular remodeling. Mechanisms involving mechanical stretch-induced leptin production and the cross talk between signaling pathways leading to vascular remodeling have not been fully elucidated. Methods and Results: Rat portal vein (RPV) organ culture was used to investigate the effect of mechanical stretch on leptin protein expression in vascular smooth muscle cells (VSMCs). Moreover, the involvement of reactive oxygen species (ROS), the RhoA/ROCK pathway, actin cytoskeleton dynamics and the transcriptional factor GATA-4 activation in mechanical stretch-induced vascular remodeling were investigated. Stretching the RPV for 1 or 24 h significantly increased leptin protein level and ROS formation in VSMCs, which was prevented by 1 h pretreatment with the ROCK inhibitor Y-27632 and the actin cytoskeleton depolymerization agent cytochalasin D. Moreover, Western blotting and immunohistochemistry revealed that mechanical stretch or treatment with 3.1 nmol/L leptin for 24 h significantly increased actin polymerization, as reflected by an increase in the F-actin to G-actin ratio. Increases in blood vessels’ wet weight and [3H]-leucine incorporation following a 24 h treatment with conditioned media from cultured stretched RPVs indicated RPV hypertrophy. This effect was prevented by 1 h pretreatment with anti-leptin antibody, indicating leptin’s crucial role in promoting VSMC hypertrophy. As an index of GATA-4 activation, GATA-4 nuclear translocation was assessed by immunohistochemistry method. Pretreating VSMC with leptin for 1 h significantly activated GATA-4 nuclear translocation, which was potently attenuated by the NADPH oxidase inhibitor apocynin, Y-27632, and cytochalasin D. Conclusion: Our results demonstrate that ROS formation, RhoA/ROCK pathway, and GATA-4 activation play a pivotal role in mechanical stretch-induced leptin synthesis leading to VSMC remodeling.
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Affiliation(s)
- Crystal M Ghantous
- Cardiovascular Physiology Lab, Department of Anatomy, Cell Biology and Physiology, American University of Beirut , Beirut, Lebanon
| | - Firas H Kobeissy
- Department of Biochemistry and Molecular Genetics, American University of Beirut , Beirut, Lebanon
| | - Nadia Soudani
- Cardiovascular Physiology Lab, Department of Anatomy, Cell Biology and Physiology, American University of Beirut , Beirut, Lebanon
| | - Farah A Rahman
- Cardiovascular Physiology Lab, Department of Anatomy, Cell Biology and Physiology, American University of Beirut , Beirut, Lebanon
| | - Mustafa Al-Hariri
- Department of Biochemistry and Molecular Genetics, American University of Beirut , Beirut, Lebanon
| | - Hana A Itani
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University School of Medicine , Nashville, TN, USA
| | - Ramzi Sabra
- Department of Pharmacology and Toxicology, American University of Beirut , Beirut, Lebanon
| | - Asad Zeidan
- Cardiovascular Physiology Lab, Department of Anatomy, Cell Biology and Physiology, American University of Beirut , Beirut, Lebanon
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Capcarova M, Petruska P, Zbynovska K, Kolesarova A, Sirotkin AV. Changes in antioxidant status of porcine ovarian granulosa cells after quercetin and T-2 toxin treatment. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2015; 50:201-206. [PMID: 25602153 DOI: 10.1080/03601234.2015.982425] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The aim of this study was to determine the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), production of reactive oxygen species (ROS), and total antioxidant status (TAS) in porcine ovarian granulosa cells after quercetin and T-2 toxin exposure in vitro. Porcine ovarian granulosa cells were incubated with quercetin and T-2 toxin separately or in mutual combination at the doses of 1 ng/mL, 10 ng/mL, 100 ng/mL, and the control group without any additions for 24 h. In this study T-2 toxin developed stress reaction in porcine ovarian granulosa cells and increased generation of ROS. Quercetin had no effect in elimination of ROS generation induced by T-2 toxin, but was effective in maintaining and increasing of TAS, activities of SOD and GPx in porcine granulosa cells in vitro. These results contribute towards the understanding of cellular stress and its response.
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Affiliation(s)
- Marcela Capcarova
- a Slovak University of Agriculture in Nitra , Faculty of Biotechnology and Food Sciences, Department of Animal Physiology , Nitra, Slovak Republic
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31
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Montezano AC, Nguyen Dinh Cat A, Rios FJ, Touyz RM. Angiotensin II and vascular injury. Curr Hypertens Rep 2014; 16:431. [PMID: 24760441 DOI: 10.1007/s11906-014-0431-2] [Citation(s) in RCA: 279] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Vascular injury, characterized by endothelial dysfunction, structural remodelling, inflammation and fibrosis, plays an important role in cardiovascular diseases. Cellular processes underlying this include altered vascular smooth muscle cell (VSMC) growth/apoptosis, fibrosis, increased contractility and vascular calcification. Associated with these events is VSMC differentiation and phenotypic switching from a contractile to a proliferative/secretory phenotype. Inflammation, associated with macrophage infiltration and increased expression of redox-sensitive pro-inflammatory genes, also contributes to vascular remodelling. Among the many factors involved in vascular injury is Ang II. Ang II, previously thought to be the sole biologically active downstream peptide of the renin-angiotensin system (RAS), is converted to smaller peptides, [Ang III, Ang IV, Ang-(1-7)], that are functional and that modulate vascular tone and structure. The actions of Ang II are mediated via signalling pathways activated upon binding to AT1R and AT2R. AT1R activation induces effects through PLC-IP3-DAG, MAP kinases, tyrosine kinases, tyrosine phosphatases and RhoA/Rho kinase. Ang II elicits many of its (patho)physiological actions by stimulating reactive oxygen species (ROS) generation through activation of vascular NAD(P)H oxidase (Nox). ROS in turn influence redox-sensitive signalling molecules. Here we discuss the role of Ang II in vascular injury, focusing on molecular mechanisms and cellular processes. Implications in vascular remodelling, inflammation, calcification and atherosclerosis are highlighted.
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Affiliation(s)
- Augusto C Montezano
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
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Balakumar P, Jagadeesh G. A century old renin-angiotensin system still grows with endless possibilities: AT1 receptor signaling cascades in cardiovascular physiopathology. Cell Signal 2014; 26:2147-60. [PMID: 25007996 DOI: 10.1016/j.cellsig.2014.06.011] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 06/27/2014] [Indexed: 12/25/2022]
Abstract
Ang II, the primary effector pleiotropic hormone of the renin-angiotensin system (RAS) cascade, mediates physiological control of blood pressure and electrolyte balance through its action on vascular tone, aldosterone secretion, renal sodium absorption, water intake, sympathetic activity and vasopressin release. It affects the function of most of the organs far beyond blood pressure control including heart, blood vessels, kidney and brain, thus, causing both beneficial and deleterious effects. However, the protective axis of the RAS composed of ACE2, Ang (1-7), alamandine, and Mas and MargD receptors might oppose some harmful effects of Ang II and might promote beneficial cardiovascular effects. Newly identified RAS family peptides, Ang A and angioprotectin, further extend the complexities in understanding the cardiovascular physiopathology of RAS. Most of the diverse actions of Ang II are mediated by AT1 receptors, which couple to classical Gq/11 protein and activate multiple downstream signals, including PKC, ERK1/2, Raf, tyrosine kinases, receptor tyrosine kinases (EGFR, PDGF, insulin receptor), nuclear factor κB and reactive oxygen species (ROS). Receptor activation via G12/13 stimulates Rho-kinase, which causes vascular contraction and hypertrophy. The AT1 receptor activation also stimulates G protein-independent signaling pathways such as β-arrestin-mediated MAPK activation and Src-JAK/STAT. AT1 receptor-mediated activation of NADPH oxidase releases ROS, resulting in the activation of pro-inflammatory transcription factors and stimulation of small G proteins such as Ras, Rac and RhoA. The components of the RAS and the major Ang II-induced signaling cascades of AT1 receptors are reviewed.
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Affiliation(s)
- Pitchai Balakumar
- Pharmacology Unit, Faculty of Pharmacy, AIMST University, Semeling, 08100 Bedong, Kedah Darul Aman, Malaysia.
| | - Gowraganahalli Jagadeesh
- Division of Cardiovascular and Renal Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD 20993, USA.
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33
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Fan LM, Li JM. Evaluation of methods of detecting cell reactive oxygen species production for drug screening and cell cycle studies. J Pharmacol Toxicol Methods 2014; 70:40-7. [PMID: 24721421 DOI: 10.1016/j.vascn.2014.03.173] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 03/25/2014] [Accepted: 03/28/2014] [Indexed: 01/22/2023]
Abstract
Intracellular reactive oxygen species (ROS) production is essential to normal cell function. However, excessive ROS production causes oxidative damage and cell death. Many pharmacological compounds exert their effects on cell cycle progression by changing intracellular redox state and in many cases cause oxidative damage leading to drug cytotoxicity. Appropriate measurement of intracellular ROS levels during cell cycle progression is therefore crucial in understanding redox-regulation of cell function and drug toxicity and for the development of new drugs. However, due to the extremely short half-life of ROS, measuring the changes in intracellular ROS levels during a particular phase of cell cycle for drug intervention can be challenging. In this article, we have provided updated information on the rationale, the applications, the advantages and limitations of common methods for screening drug effects on intracellular ROS production linked to cell cycle study. Our aim is to facilitate biomedical scientists and researchers in the pharmaceutical industry in choosing or developing specific experimental regimens to suit their research needs.
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Affiliation(s)
- Lampson M Fan
- John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - Jian-Mei Li
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK.
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Z. Alanazi A, Patel P, Clark MA. p38 Mitogen-activated protein kinase is stimulated by both angiotensin II and angiotensin III in cultured rat astrocytes. J Recept Signal Transduct Res 2014; 34:205-11. [DOI: 10.3109/10799893.2013.876041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Nguyen Dinh Cat A, Montezano AC, Burger D, Touyz RM. Angiotensin II, NADPH oxidase, and redox signaling in the vasculature. Antioxid Redox Signal 2013; 19:1110-20. [PMID: 22530599 PMCID: PMC3771549 DOI: 10.1089/ars.2012.4641] [Citation(s) in RCA: 316] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Angiotensin II (Ang II) influences the function of many cell types and regulates many organ systems, in large part through redox-sensitive processes. In the vascular system, Ang II is a potent vasoconstrictor and also promotes inflammation, hypertrophy, and fibrosis, which are important in vascular damage and remodeling in cardiovascular diseases. The diverse actions of Ang II are mediated via Ang II type 1 and Ang II type 2 receptors, which couple to various signaling molecules, including NADPH oxidase (Nox), which generates reactive oxygen species (ROS). ROS are now recognized as signaling molecules, critically placed in pathways activated by Ang II. Mechanisms linking Nox and Ang II are complex and not fully understood. RECENT ADVANCES Ang II regulates vascular cell production of ROS through various recently characterized Noxs, including Nox1, Nox2, Nox4, and Nox5. Activation of these Noxs leads to ROS generation, which in turn influences many downstream signaling targets of Ang II, including MAP kinases, RhoA/Rho kinase, transcription factors, protein tyrosine phosphatases, and tyrosine kinases. Activation of these redox-sensitive pathways regulates vascular cell growth, inflammation, contraction, and senescence. CRITICAL ISSUES Although there is much evidence indicating a role for Nox/ROS in Ang II function, there is still a paucity of information on how Ang II exerts cell-specific effects through ROS and how Nox isoforms are differentially regulated by Ang II. Moreover, exact mechanisms whereby ROS induce oxidative modifications of signaling molecules mediating Ang II actions remain elusive. FUTURE DIRECTIONS Future research should elucidate these issues to better understand the significance of Ang II and ROS in vascular (patho) biology.
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Affiliation(s)
- Aurelie Nguyen Dinh Cat
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada
| | - Augusto C. Montezano
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada
| | - Dylan Burger
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada
| | - Rhian M. Touyz
- Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada
- Institute of Cardiovascular and Medical Sciences, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, United Kingdom
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36
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Wu J, Tu D, Yuan LY, Yuan H, Wen LX. T-2 toxin exposure induces apoptosis in rat ovarian granulosa cells through oxidative stress. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2013; 36:493-500. [PMID: 23811107 DOI: 10.1016/j.etap.2013.03.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 06/02/2023]
Abstract
OBJECTIVE To investigate the reproductive toxicity and cytotoxicity of T-2 toxin, which is a mycotoxin, and to explore its potential apoptotic induction mechanism. METHODS ovarian granulosa cells of rats were treated with T-2 toxin (1-100nM) for 24h. The cytotoxicity was assessed with MTT bioassay and apoptotic cells were detected by flow cytometry, and further identified by chromatin condensation and nuclear fragmentation with Hoechst 33258 under microscope; reactive oxygen species (ROS) with DCFH-DA was analyzed by fluorometry; total superoxide dismutase (SOD) was determined by NBT staining method. Glutathione peroxidase (GSHPx) activity was detected by UV colorimetric assay. The activity of catalase (CAT) in granulosa cells was measured by the Aebi method, and malondialdehyde (MDA) content was determined by thiobarbituric acid assay. RESULTS T-2 toxin dose-dependently inhibited the growth of granulosa cells and resulted in apoptosis in rat granulosa cells. Treatment with T-2 toxin could induce ROS and MDA accumulation in granulosa cells, acompanying with losses of activities of SOD, GSH-Px and CAT, whereas T-2 toxin-induced apoptosis in granulosa cells could be significantly inhibited through the use of antioxidant Trolox. CONCLUSION These data suggest that T-2 toxin may induce the apoptosis in rat granulosa cells through oxidative stress.
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Affiliation(s)
- Jing Wu
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan 410128, PR China
| | - Di Tu
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan 410128, PR China
| | - Li-Yun Yuan
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan 410128, PR China
| | - Hui Yuan
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan 410128, PR China
| | - Li-Xin Wen
- College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan 410128, PR China.
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37
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Oxidative stress induced by P2X7 receptor stimulation in murine macrophages is mediated by c-Src/Pyk2 and ERK1/2. Biochim Biophys Acta Gen Subj 2013; 1830:4650-9. [PMID: 23711511 DOI: 10.1016/j.bbagen.2013.05.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/11/2013] [Accepted: 05/15/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND Activation of ATP-gated P2X7 receptors (P2X7R) in macrophages leads to production of reactive oxygen species (ROS) by a mechanism that is partially characterized. Here we used J774 cells to identify the signaling cascade that couples ROS production to receptor stimulation. METHODS J774 cells and mP2X7-transfected HEK293 cells were stimulated with Bz-ATP in the presence and absence of extracellular calcium. Protein inhibitors were used to evaluate the physiological role of various kinases in ROS production. In addition, phospho-antibodies against ERK1/2 and Pyk2 were used to determine activation of these two kinases. RESULTS ROS generation in either J774 or HEK293 cells (expressing P2X7, NOX2, Rac1, p47phox and p67phox) was strictly dependent on calcium entry via P2X7R. Stimulation of P2X7R activated Pyk2 but not calmodulin. Inhibitors of MEK1/2 and c-Src abolished ERK1/2 activation and ROS production but inhibitors of PI3K and p38 MAPK had no effect on ROS generation. PKC inhibitors abolished ERK1/2 activation but barely reduced the amount of ROS produced by Bz-ATP. In agreement, the amount of ROS produced by PMA was about half of that produced by Bz-ATP. CONCLUSIONS Purinergic stimulation resulted in calcium entry via P2X7R and subsequent activation of the PKC/c-Src/Pyk2/ERK1/2 pathway to produce ROS. This signaling mechanism did not require PI3K, p38 MAPK or calmodulin. GENERAL SIGNIFICANCE ROS is generated in order to kill invading pathogens, thus elucidating the mechanism of ROS production in macrophages and other immune cells allow us to understand how our body copes with microbial infections.
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Takada S, Kinugawa S, Hirabayashi K, Suga T, Yokota T, Takahashi M, Fukushima A, Homma T, Ono T, Sobirin MA, Masaki Y, Mizushima W, Kadoguchi T, Okita K, Tsutsui H. Angiotensin II receptor blocker improves the lowered exercise capacity and impaired mitochondrial function of the skeletal muscle in type 2 diabetic mice. J Appl Physiol (1985) 2013; 114:844-57. [DOI: 10.1152/japplphysiol.00053.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
NAD(P)H oxidase-induced oxidative stress is at least in part involved with lowered exercise capacity and impaired mitochondrial function in high-fat diet (HFD)-induced diabetic mice. NAD(P)H oxidase can be activated by activation of the renin-angiotensin system. We investigated whether ANG II receptor blocker can improve exercise capacity in diabetic mice. C57BL/6J mice were fed a normal diet (ND) or HFD, and each group of mice was divided into two groups: treatment with or without olmesartan (OLM; 3 mg·kg−1·day−1 in the drinking water). The following groups of mice were studied: ND, ND+OLM, HFD, and HFD+OLM ( n = 10 for each group). After 8 wk, HFD significantly increased body weight, plasma glucose, and insulin compared with ND, and OLM did not affect these parameters in either group. Exercise capacity, as determined by treadmill tests, was significantly reduced in HFD, and this reduction was ameliorated in HFD+OLM. ADP-dependent mitochondrial respiration was significantly decreased, and NAD(P)H oxidase activity and superoxide production by lucigenin chemiluminescence were significantly increased in skeletal muscle from HFD, which were attenuated by OLM. There were no such effects by OLM in ND. We concluded that OLM ameliorated the decrease in exercise capacity in diabetic mice via improvement in mitochondrial function and attenuation of oxidative stress in skeletal muscle. These data may have a clinical impact on exercise capacity in the medical treatment of diabetes mellitus.
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Affiliation(s)
- Shingo Takada
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Research Fellow of the Japan Society for the Promotion of Science
| | - Shintaro Kinugawa
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kagami Hirabayashi
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Tadashi Suga
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Research Fellow of the Japan Society for the Promotion of Science
| | - Takashi Yokota
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Masashige Takahashi
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Arata Fukushima
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Tsuneaki Homma
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Taisuke Ono
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | | | - Yoshihiro Masaki
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Wataru Mizushima
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Tomoyasu Kadoguchi
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Koichi Okita
- Graduate School of Program in Lifelong Learning Studies, Hokusho University, Ebetsu, Japan
| | - Hiroyuki Tsutsui
- Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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Yin W, Voit EO. Function and design of the Nox1 system in vascular smooth muscle cells. BMC SYSTEMS BIOLOGY 2013; 7:20. [PMID: 23497394 PMCID: PMC3606394 DOI: 10.1186/1752-0509-7-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 02/18/2013] [Indexed: 11/24/2022]
Abstract
Background Recent studies have demonstrated that the activation of NADPH oxidase 1 (Nox1) plays an important role in the control of reactive oxygen species and their involvement in vascular physiology and pathophysiology. In order to function properly, Nox1 needs to be available in an optimal state, where it is ready to respond appropriately and efficiently to upstream signals. It must also be able to return quickly to this state as soon as the input signal disappears. While Nox1 activation has been discussed extensively in recent years, mechanisms for enzyme disassembly and proper subunit recovery have not received the same attention and therefore require investigation. Results We study the Nox1 system in vascular smooth smucle cells and propose four potential disassembly mechanisms. The analysis consists primarily of large-scale Monte-Carlo simulations whose results are essentially independent of specific parameter values. The computational analysis shows that a specific profile of subunit concentrations is crucial for optimal functioning and responsiveness of the system to input signals. Specifically, free p47phox and inactive Rac1 should be dominant under unstimulated resting conditions, and the proteolytic disassembly pathway should have a low flux, as it is relatively inefficient. The computational results also reveal that the optimal design of the three subunit recovery pathways depends on the intracellular settings of the pathway and that the response speeds of key reversible reactions within the pathway are of great importance. Conclusions Our results provide a systematic basis for understanding the dynamics of Nox1 and yield novel insights into its crucially important disassembly mechanisms. The rigorous comparisons of the relative importance of four potential disassembly pathways demonstrate that disassembly via proteolysis is the least effective mechanism. The relative significance of the other three recovery pathways varies among different scenarios. It is greatly affected by the required response speed of the system and depends critically on appropriate flux balances between forward and reverse reactions. Our findings are predictive and pose novel hypotheses that should be validated with future experiments.
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Affiliation(s)
- Weiwei Yin
- The Wallace H, Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Williams JT, Ingram SL, Henderson G, Chavkin C, von Zastrow M, Schulz S, Koch T, Evans CJ, Christie MJ. Regulation of μ-opioid receptors: desensitization, phosphorylation, internalization, and tolerance. Pharmacol Rev 2013; 65:223-54. [PMID: 23321159 DOI: 10.1124/pr.112.005942] [Citation(s) in RCA: 585] [Impact Index Per Article: 53.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Morphine and related µ-opioid receptor (MOR) agonists remain among the most effective drugs known for acute relief of severe pain. A major problem in treating painful conditions is that tolerance limits the long-term utility of opioid agonists. Considerable effort has been expended on developing an understanding of the molecular and cellular processes that underlie acute MOR signaling, short-term receptor regulation, and the progression of events that lead to tolerance for different MOR agonists. Although great progress has been made in the past decade, many points of contention and controversy cloud the realization of this progress. This review attempts to clarify some confusion by clearly defining terms, such as desensitization and tolerance, and addressing optimal pharmacological analyses for discerning relative importance of these cellular mechanisms. Cellular and molecular mechanisms regulating MOR function by phosphorylation relative to receptor desensitization and endocytosis are comprehensively reviewed, with an emphasis on agonist-biased regulation and areas where knowledge is lacking or controversial. The implications of these mechanisms for understanding the substantial contribution of MOR signaling to opioid tolerance are then considered in detail. While some functional MOR regulatory mechanisms contributing to tolerance are clearly understood, there are large gaps in understanding the molecular processes responsible for loss of MOR function after chronic exposure to opioids. Further elucidation of the cellular mechanisms that are regulated by opioids will be necessary for the successful development of MOR-based approaches to new pain therapeutics that limit the development of tolerance.
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Affiliation(s)
- John T Williams
- Vollum Institute, Oregon Health Sciences University, Portland, Oregon, USA
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41
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Yogi A, Callera GE, Mecawi AS, Batalhão ME, Carnio EC, Antunes-Rodrigues J, Queiroz RH, Touyz RM, Tirapelli CR. Acute ethanol intake induces superoxide anion generation and mitogen-activated protein kinase phosphorylation in rat aorta: A role for angiotensin type 1 receptor. Toxicol Appl Pharmacol 2012; 264:470-8. [DOI: 10.1016/j.taap.2012.08.029] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 08/20/2012] [Accepted: 08/21/2012] [Indexed: 01/14/2023]
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Csongradi E, Juncos LA, Drummond HA, Vera T, Stec DE. Role of carbon monoxide in kidney function: is a little carbon monoxide good for the kidney? Curr Pharm Biotechnol 2012; 13:819-26. [PMID: 22201605 DOI: 10.2174/138920112800399284] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Accepted: 08/28/2010] [Indexed: 12/13/2022]
Abstract
Carbon monoxide (CO) is an endogenously produced gas resulting from the degradation of heme by heme oxygense or from fatty acid oxidation. Heme oxygenase (HO) enzymes are constitutively expressed in the kidney (HO-2) and HO-1 is induced in the kidney in response to several physiological and pathological stimuli. While the beneficial actions of HO in the kidney have been recognized for some time, the important role of CO in mediating these effects has not been fully examined. Recent studies using CO inhalation therapy and carbon monoxide releasing molecules (CORMs) have demonstrated that increases in CO alone can be beneficial to the kidney in several forms of acute renal injury by limiting oxidative injury, decreasing cell apoptosis, and promoting cell survival pathways. Renal CO is also emerging as a major regulator of renal vascular and tubular function acting to protect the renal vasculature against excessive vasoconstriction and to promote natriuresis by limiting sodium reabsorption in tubule cells. Within this review, recent studies on the physiological actions of CO in the kidney will be explored as well as the potential therapeutic avenues that are being developed targeting CO in the kidney which may be beneficial in diseases such as acute renal failure and hypertension.
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Affiliation(s)
- Eva Csongradi
- Department of Physiology & Biophysics, Center for Excellence in Cardiovascular-Renal Research, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Salhan D, Husain M, Subrati A, Goyal R, Singh T, Rai P, Malhotra A, Singhal PC. HIV-induced kidney cell injury: role of ROS-induced downregulated vitamin D receptor. Am J Physiol Renal Physiol 2012; 303:F503-14. [PMID: 22647636 PMCID: PMC3774077 DOI: 10.1152/ajprenal.00170.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 05/29/2012] [Indexed: 01/31/2023] Open
Abstract
Reactive oxygen species (ROS) have been demonstrated to contribute to HIV-induced tubular cell injury. We hypothesized that HIV-induced ROS generation may be causing tubular cell injury through downregulation of vitamin D receptor (VDR) and associated downstream effects. In the present study, HIV not only downregulated tubular cell VDR expression but also inflicted DNA injury. On the other hand, EB-1089, a VDR agonist (VD), inhibited both downregulation of VDR and tubular cell DNA injury in the HIV milieu. H(2)O(2) (an O(-) donor) directly downregulated tubular cell VDR, whereas catalase, a free radical scavenger, inhibited HIV-induced downregulation of tubular cell VDR expression. HIV also stimulated the tubular cell renin-angiotensin system (RAS) through downregulation of VDR. Because losartan (an ANG II blolcker) partially inhibited HIV-induced tubular cell ROS generation while ANG II directly stimulated tubular cell ROS generation, it appears that HIV-induced ROS production was partly contributed by the RAS activation. VD not only inhibited HIV-induced RAS activation but also attenuated tubular cell ROS generation. Tubular cells displayed double jeopardy in the HIV milieu induction of double-strand breaks and attenuated DNA repair; additionally, in the HIV milieu, tubular cells exhibited enhanced expression of phospho-p53 and associated downstream signaling. A VDR agonist and an ANG II blocker not only preserved expression of tubular cell DNA repair proteins but also inhibited induction of double-strand breaks. In in vivo studies, renal cortical sections of Tg26 mice displayed attenuated expression of VDR both in podocytes and tubular cells. In addition, renal cortical sections of Tg26 mice displayed enhanced oxidative stress-induced kidney cell DNA damage. These findings indicated that HIV-induced tubular cell downregulation of VDR contributed to the RAS activation and associated tubular cell DNA damage. However, both VD and RAS blockade provided protection against these effects of HIV.
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Affiliation(s)
- Divya Salhan
- Immunology Center, Feinstein Institute for Medical Research, Hofstra North Shore LIJ Medical School, Great Neck, New York, USA
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Rajamohan SB, Raghuraman G, Prabhakar NR, Kumar GK. NADPH oxidase-derived H(2)O(2) contributes to angiotensin II-induced aldosterone synthesis in human and rat adrenal cortical cells. Antioxid Redox Signal 2012; 17:445-59. [PMID: 22214405 PMCID: PMC3365360 DOI: 10.1089/ars.2011.4176] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The Renin-Angiotensin-Aldosterone-System plays a pivotal role in hypertension. Angiotensin II (Ang II) is a major regulator of aldosterone synthesis and secretion, and it is known to facilitate reactive oxygen species (ROS) generation in many cell types. AIMS Here, we assessed the role of ROS signaling in Ang II-induced aldosterone synthesis by focusing on the regulation of aldosterone synthase (CYP11B2), a cytochrome P450 oxidase that catalyzes the final step in aldosterone biosynthetic pathway. RESULTS Ang II increased CYP11B2 activity, mRNA and protein with a concomitant elevation of 6-Carboxy- 2',7'-dichlorodihydrofluorescein diacetate fluorescence, malondialdehyde and protein carbonyl levels (indices of ROS), NADPH oxidase (Nox) activity, and H(2)O(2) levels in human and rat adrenal cortical cells. The expression of nuclear receptor related 1 protein, a transcription factor known to regulate CYP11B2 expression, was also augmented by Ang II. These Ang II-evoked effects were either abolished or attenuated by pretreatment of cells with either Ang II type I receptor (AT(1)R) antagonist, or antioxidants or Nox inhibitor or siRNA silencing of Nox1, 2 and 4, or inhibitors of phospholipase C and protein kinase C. Exogenous H(2)O(2) mimicked the facilitatory effects of Ang II on CYP11B2 activity, mRNA, and protein expression, and these changes were significantly reduced by PEG-catalase. INNOVATION ROS, particularly H(2)O(2), is identified as a key regulator of aldosterone production. CONCLUSION Our results suggest that Ang II facilitates CYP11B2 activity and the ensuing aldosterone production via activation of AT(1)R-Nox-H(2)O(2) signaling pathway.
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Affiliation(s)
- Senthilkumar B Rajamohan
- Department of Medicine, Institute for Integrative Physiology, University of Chicago, Chicago, IL 60637-1470, USA
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Wang Y, Kuro-o M, Sun Z. Klotho gene delivery suppresses Nox2 expression and attenuates oxidative stress in rat aortic smooth muscle cells via the cAMP-PKA pathway. Aging Cell 2012; 11:410-7. [PMID: 22260450 DOI: 10.1111/j.1474-9726.2012.00796.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Klotho is a recently discovered anti-aging gene. The purpose of this study was to investigate whether klotho gene transfer attenuates superoxide production and oxidative stress in rat aorta smooth muscle (RASM) cells. RASM cells were transfected with AAV plasmids carrying mouse klotho full-length cDNA (mKL) or LacZ as a control. Klotho gene transfer increased klotho expression in RASM cells. Notably, klotho gene expression decreased Nox2 NADPH oxidase protein expression but did not affect Nox2 mRNA expression, suggesting that the inhibition may occur at the posttranscriptional level. Klotho gene transfer decreased intracellular superoxide production and oxidative stress in RASM cells. Klotho gene expression also significantly attenuated the angiotensin II (AngII)-induced superoxide production, oxidative damage, and apoptosis. Interestingly, klotho gene delivery dose dependently increased the intracellular cAMP level and PKA activity in RASM cells. Rp-cAMP, a competitive inhibitor of cAMP, abolished the klotho-induced increase in PKA activity, indicating that klotho activated PKA via cAMP. Notably, inhibition of cAMP-dependent PKA activity by RP-cAMP abolished klotho-induced inhibition of Nox2 protein expression, suggesting an important role of cAMP-dependent PKA in this process. This finding revealed a previously unidentified role of klotho in regulating Nox2 protein expression in RASM cells. Klotho not only downregulated Nox2 protein expression and intracellular superoxide production but also attenuated AngII-induced superoxide production, oxidative damage, and apoptosis. The klotho-induced suppression of Nox2 protein expression may be mediated by the cAMP-PKA pathway.
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Affiliation(s)
- Yuhong Wang
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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46
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Taverne YJHJ, de Beer VJ, Hoogteijling BA, Juni RP, Moens AL, Duncker DJ, Merkus D. Nitroso-redox balance in control of coronary vasomotor tone. J Appl Physiol (1985) 2012; 112:1644-52. [PMID: 22362403 DOI: 10.1152/japplphysiol.00479.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reactive oxygen species (ROS) are essential in vascular homeostasis but may contribute to vascular dysfunction when excessively produced. Superoxide anion (O(2)(·-)) can directly affect vascular tone by reacting with K(+) channels and indirectly by reacting with nitric oxide (NO), thereby scavenging NO and causing nitroso-redox imbalance. After myocardial infarction (MI), oxidative stress increases, favoring the imbalance and resulting in coronary vasoconstriction. Consequently, we hypothesized that ROS scavenging results in coronary vasodilation, particularly after MI, and is enhanced after inhibition of NO production. Chronically instrumented swine were studied at rest and during exercise before and after scavenging of ROS with N-(2-mercaptoproprionyl)-glycine (MPG, 20 mg/kg iv) in the presence or absence of prior inhibition of endothelial NO synthase (eNOS) with N(ω)-nitro-L-arginine (L-NNA, 20 mg/kg iv). In normal swine, MPG resulted in coronary vasodilation as evidenced by an increased coronary venous O(2) tension, and trends toward increased coronary venous O(2) saturation and decreased myocardial O(2) extraction. These effects were not altered by prior inhibition of eNOS. In MI swine, MPG showed a significant vasodilator effect, which surprisingly was abolished by prior inhibition of eNOS. Moreover, eNOS dimer/monomer ratio was decreased after MI, reflecting eNOS uncoupling. In conclusion, ROS exert a small coronary vasoconstrictor influence in normal swine, which does not involve scavenging of NO. This vasoconstrictor influence of ROS is slightly enhanced after MI. Since inhibition of eNOS abolished rather than augmented the vasoconstrictor influence of ROS in swine with MI, while eNOS dimer/monomer ratio was decreased, our data imply that uncoupled eNOS may be a significant source of O(2)(·-) after MI.
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Affiliation(s)
- Yannick J H J Taverne
- Experimental Cardiology, Thoraxcenter, Cardiovascular Research Institute COEUR, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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47
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Wang Y, Kuro-o M, Sun Z. Klotho gene delivery suppresses Nox2 expression and attenuates oxidative stress in rat aortic smooth muscle cells via the cAMP-PKA pathway. Aging Cell 2012. [PMID: 22260450 DOI: 10.1111/j.1474-9726.2012.00796.x.] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Klotho is a recently discovered anti-aging gene. The purpose of this study was to investigate whether klotho gene transfer attenuates superoxide production and oxidative stress in rat aorta smooth muscle (RASM) cells. RASM cells were transfected with AAV plasmids carrying mouse klotho full-length cDNA (mKL) or LacZ as a control. Klotho gene transfer increased klotho expression in RASM cells. Notably, klotho gene expression decreased Nox2 NADPH oxidase protein expression but did not affect Nox2 mRNA expression, suggesting that the inhibition may occur at the posttranscriptional level. Klotho gene transfer decreased intracellular superoxide production and oxidative stress in RASM cells. Klotho gene expression also significantly attenuated the angiotensin II (AngII)-induced superoxide production, oxidative damage, and apoptosis. Interestingly, klotho gene delivery dose dependently increased the intracellular cAMP level and PKA activity in RASM cells. Rp-cAMP, a competitive inhibitor of cAMP, abolished the klotho-induced increase in PKA activity, indicating that klotho activated PKA via cAMP. Notably, inhibition of cAMP-dependent PKA activity by RP-cAMP abolished klotho-induced inhibition of Nox2 protein expression, suggesting an important role of cAMP-dependent PKA in this process. This finding revealed a previously unidentified role of klotho in regulating Nox2 protein expression in RASM cells. Klotho not only downregulated Nox2 protein expression and intracellular superoxide production but also attenuated AngII-induced superoxide production, oxidative damage, and apoptosis. The klotho-induced suppression of Nox2 protein expression may be mediated by the cAMP-PKA pathway.
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Affiliation(s)
- Yuhong Wang
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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48
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Sutcliffe A, Hollins F, Gomez E, Saunders R, Doe C, Cooke M, Challiss RAJ, Brightling CE. Increased nicotinamide adenine dinucleotide phosphate oxidase 4 expression mediates intrinsic airway smooth muscle hypercontractility in asthma. Am J Respir Crit Care Med 2011; 185:267-74. [PMID: 22108207 DOI: 10.1164/rccm.201107-1281oc] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Asthma is characterized by disordered airway physiology as a consequence of increased airway smooth muscle contractility. The underlying cause of this hypercontractility is poorly understood. OBJECTIVES We sought to investigate whether the burden of oxidative stress in airway smooth muscle in asthma is heightened and mediated by an intrinsic abnormality promoting hypercontractility. METHODS We examined the oxidative stress burden of airway smooth muscle in bronchial biopsies and primary cells from subjects with asthma and healthy controls. We determined the expression of targets implicated in the control of oxidative stress in airway smooth muscle and their role in contractility. MEASUREMENTS AND MAIN RESULTS We found that the oxidative stress burden in the airway smooth muscle in individuals with asthma is heightened and related to the degree of airflow obstruction and airway hyperresponsiveness. This was independent of the asthmatic environment as in vitro primary airway smooth muscle from individuals with asthma compared with healthy controls demonstrated increased oxidative stress-induced DNA damage together with an increased production of reactive oxygen species. Genome-wide microarray of primary airway smooth muscle identified increased messenger RNA expression in asthma of NADPH oxidase (NOX) subtype 4. This NOX4 overexpression in asthma was supported by quantitative polymerase chain reaction, confirmed at the protein level. Airway smooth muscle from individuals with asthma exhibited increased agonist-induced contraction. This was abrogated by NOX4 small interfering RNA knockdown and the pharmacological inhibitors diphenyleneiodonium and apocynin. CONCLUSIONS Our findings support a critical role for NOX4 overexpression in asthma in the promotion of oxidative stress and consequent airway smooth muscle hypercontractility. This implicates NOX4 as a potential novel target for asthma therapy.
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Affiliation(s)
- Amanda Sutcliffe
- Institute for Lung Health, Department of Infection, Immunity and Inflammation, University of Leicester, United Kingdom
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Virdis A, Duranti E, Taddei S. Oxidative Stress and Vascular Damage in Hypertension: Role of Angiotensin II. Int J Hypertens 2011; 2011:916310. [PMID: 21747985 PMCID: PMC3124711 DOI: 10.4061/2011/916310] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Accepted: 03/16/2011] [Indexed: 02/06/2023] Open
Abstract
Reactive oxygen species are oxygen derivates and play an active role in vascular biology. These compounds are generated within the vascular wall, at the level of endothelial and vascular smooth muscle cells, as well as by adventitial fibroblasts. In healthy conditions, ROS are produced in a controlled manner at low concentrations and function as signaling molecules regulating vascular contraction-relaxation and cell growth. Physiologically, the rate of ROS generation is counterbalanced by the rate of elimination. In hypertension, an enhanced ROS generation occurs, which is not counterbalanced by the endogenous antioxidant mechanisms, leading to a state of oxidative stress. In the present paper, major angiotensin II-induced vascular ROS generation within the vasculature, and relative sources, will be discussed. Recent development of signalling pathways whereby angiotensin II-driven vascular ROS induce and accelerate functional and structural vascular injury will be also considered.
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Affiliation(s)
- Agostino Virdis
- Department of Internal Medicine, University of Pisa, 56100 Pisa, Italy
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50
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Sedeek M, Callera G, Montezano A, Gutsol A, Heitz F, Szyndralewiez C, Page P, Kennedy CRJ, Burns KD, Touyz RM, Hébert RL. Critical role of Nox4-based NADPH oxidase in glucose-induced oxidative stress in the kidney: implications in type 2 diabetic nephropathy. Am J Physiol Renal Physiol 2010; 299:F1348-58. [DOI: 10.1152/ajprenal.00028.2010] [Citation(s) in RCA: 299] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Molecular mechanisms underlying renal complications of diabetes remain unclear. We tested whether renal NADPH oxidase (Nox) 4 contributes to increased reactive oxygen species (ROS) generation and hyperactivation of redox-sensitive signaling pathways in diabetic nephropathy. Diabetic mice ( db/ db) (20 wk) and cultured mouse proximal tubule (MPT) cells exposed to high glucose (25 mmol/l, d-glucose) were studied. Expression (gene and protein) of Nox4, p22phox, and p47phox, but not Nox1 or Nox2, was increased in kidney cortex, but not medulla, from db/ db vs. control mice ( db/ m) ( P < 0.05). ROS generation, p38 mitogen-activated protein (MAP) kinase phosphorylation, and content of fibronectin and transforming growth factor (TGF)-β1/2 were increased in db/ db vs. db/ m ( P < 0.01). High glucose increased expression of Nox4, but not other Noxes vs. normal glucose ( P < 0.05). This was associated with increased NADPH oxidase activation and enhanced ROS production. Nox4 downregulation by small-interfering RNA and inhibition of Nox4 activity by GK-136901 (Nox1/4 inhibitor) attenuated d-glucose-induced NADPH oxidase-derived ROS generation. High d-glucose, but not l-glucose, stimulated phosphorylation of p38MAP kinase and increased expression of TGF-β1/2 and fibronectin, effects that were inhibited by SB-203580 (p38MAP kinase inhibitor). GK-136901 inhibited d-glucose-induced actions. Our data indicate that, in diabetic conditions: 1) renal Nox4 is upregulated in a cortex-specific manner, 2) MPT cells possess functionally active Nox4-based NADPH, 3) Nox4 is a major source of renal ROS, and 4) activation of profibrotic processes is mediated via Nox4-sensitive, p38MAP kinase-dependent pathways. These findings implicate Nox4-based NADPH oxidase in molecular mechanisms underlying fibrosis in type 2 diabetic nephropathy.
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Affiliation(s)
- M. Sedeek
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - G. Callera
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - A. Montezano
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - A. Gutsol
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | | | | | - P. Page
- GenKyoTex, Geneva, Switzerland
| | - C. R. J. Kennedy
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - K. D. Burns
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - R. M. Touyz
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
| | - R. L. Hébert
- Kidney Research Centre, Ottawa Hospital Research Institute and Deptartment of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada; and
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