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Li C, Sun H, Xu G, McCarter KD, Li J, Mayhan WG. Mito-Tempo prevents nicotine-induced exacerbation of ischemic brain damage. J Appl Physiol (1985) 2018; 125:49-57. [PMID: 29420160 DOI: 10.1152/japplphysiol.01084.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Nicotine may contribute to the pathogenesis of cerebrovascular disease via the generation of reactive oxygen species (ROS). Overproduction of ROS leads to brain damage by intensifying postischemic inflammation. Our goal was to determine the effect of Mito-Tempo, a mitochondria-targeted antioxidant, on ischemic brain damage and postischemic inflammation during chronic exposure to nicotine. Male Sprague-Dawley rats were divided into four groups: control, nicotine, Mito-Tempo-treated control, and Mito-Tempo-treated nicotine. Nicotine (2 mg·kg-1·day-1) was administered via an osmotic minipump for 4 wk. Mito-Tempo (0.7 mg·kg-1·day-1 ip) was given for 7 days before cerebral ischemia. Transient focal cerebral ischemia was induced by occlusion of the middle cerebral artery for 2 h. Brain damage and inflammation were evaluated after 24 h of reperfusion by measuring infarct volume, expression of adhesion molecules, activity of matrix metalloproteinase, brain edema, microglial activation, and neutrophil infiltration. Nicotine exacerbated infarct volume and worsened neurological deficits. Nicotine did not alter baseline ICAM-1 expression, matrix metallopeptidase-2 activity, microglia activation, or neutrophil infiltration but increased these parameters after cerebral ischemia. Mito-Tempo did not have an effect in control rats but prevented the chronic nicotine-induced augmentation of ischemic brain damage and postischemic inflammation. We suggest that nicotine increases brain damage following cerebral ischemia via an increase in mitochondrial oxidative stress, which, in turn, contributes to postischemic inflammation. NEW & NOTEWORTHY Our findings have important implications for the understanding of mechanisms contributing to increased susceptibility of the brain to damage in smokers and users of nicotine-containing tobacco products.
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Affiliation(s)
- Chun Li
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport , Shreveport, Louisiana
| | - Hong Sun
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport , Shreveport, Louisiana
| | - Guodong Xu
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport , Shreveport, Louisiana.,Department of Neurology, Hebei General Hospital , Shijiazhuang, Hebei , China
| | - Kimberly D McCarter
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport , Shreveport, Louisiana
| | - Jiyu Li
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport , Shreveport, Louisiana
| | - William G Mayhan
- Division of Basic Biomedical Sciences, Sanford School of Medicine, The University of South Dakota, Vermillion, South Dakota
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Mayhan WG, Arrick DM. Tetrahydrobiopterin rescues impaired responses of cerebral resistance arterioles during type 1 diabetes. Diab Vasc Dis Res 2017; 14:33-39. [PMID: 27941054 DOI: 10.1177/1479164116675490] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Our goal was to test the hypothesis that administration of tetrahydrobiopterin (BH4) would improve impaired endothelial nitric oxide synthase-dependent dilation of cerebral arterioles during type 1 diabetes. In addition, we examined the influence of BH4 on levels of superoxide in brain tissue. In vivo diameter of cerebral arterioles in nondiabetic and diabetic rats was measured in response to endothelial nitric oxide synthase-dependent agonists (acetylcholine and adenosine 5'-diphosphate) and an endothelial nitric oxide synthase-independent agonist (nitroglycerine) before and during application of BH4 (1.0 µM). We also measured levels of superoxide from cortex tissue in nondiabetic and diabetic rats under basal states and during BH4 Acetylcholine and adenosine 5'-diphosphate dilated cerebral arterioles in nondiabetic rats, but this vasodilation was significantly impaired in diabetic rats. In contrast, nitroglycerine produced similar vasodilation in nondiabetic and diabetic rats. Application of BH4 did not enhance vasodilation in nondiabetic rats but improved impaired cerebral vasodilation in diabetic rats. Basal superoxide levels were increased in cortex tissue from diabetic rats, and BH4 reduced these levels to that found in nondiabetic rats. Thus, BH4 is an important mediator of endothelial nitric oxide synthase-dependent responses of cerebral arterioles in diabetes and may have therapeutic potential for the treatment of cerebral vascular disease.
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Affiliation(s)
- William G Mayhan
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
| | - Denise M Arrick
- Division of Basic Biomedical Sciences, Sanford School of Medicine, University of South Dakota, Vermillion, SD, USA
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De Silva TM, Faraci FM. Reactive Oxygen Species and the Regulation of Cerebral Vascular Tone. STUDIES ON ATHEROSCLEROSIS 2017. [DOI: 10.1007/978-1-4899-7693-2_6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Toda N, Okamura T. Cigarette smoking impairs nitric oxide-mediated cerebral blood flow increase: Implications for Alzheimer's disease. J Pharmacol Sci 2016; 131:223-32. [DOI: 10.1016/j.jphs.2016.07.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/05/2016] [Accepted: 07/06/2016] [Indexed: 02/08/2023] Open
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Microvascular Dysfunction and Cognitive Impairment. Cell Mol Neurobiol 2016; 36:241-58. [PMID: 26988697 DOI: 10.1007/s10571-015-0308-1] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 11/19/2015] [Indexed: 12/18/2022]
Abstract
The impact of vascular risk factors on cognitive function has garnered much interest in recent years. The appropriate distribution of oxygen, glucose, and other nutrients by the cerebral vasculature is critical for proper cognitive performance. The cerebral microvasculature is a key site of vascular resistance and a preferential target for small vessel disease. While deleterious effects of vascular risk factors on microvascular function are known, the contribution of this dysfunction to cognitive deficits is less clear. In this review, we summarize current evidence for microvascular dysfunction in brain. We highlight effects of select vascular risk factors (hypertension, diabetes, and hyperhomocysteinemia) on the pial and parenchymal circulation. Lastly, we discuss potential links between microvascular disease and cognitive function, highlighting current gaps in our understanding.
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Li C, Sun H, Arrick DM, Mayhan WG. Chronic nicotine exposure exacerbates transient focal cerebral ischemia-induced brain injury. J Appl Physiol (1985) 2016; 120:328-33. [DOI: 10.1152/japplphysiol.00663.2015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/03/2015] [Indexed: 01/30/2023] Open
Abstract
Tobacco smoking is a risk factor contributing to the development and progression of ischemic stroke. Among many chemicals in tobacco, nicotine may be a key contributor. We hypothesized that nicotine alters the balance between oxidant and antioxidant networks leading to an increase in brain injury following transient focal cerebral ischemia. Male Sprague-Dawley were treated with nicotine (2 or 4 mg·kg−1·day−1) for 4 wk via an implanted subcutaneous osmotic minipump and subjected to a 2-h middle cerebral artery occlusion (MCAO). Infarct size and neurological deficits were evaluated at 24 h of reperfusion. Superoxide levels were determined by lucigenin-enhanced chemiluminescence. Expression of oxidant and antioxidant proteins was measured using Western blot analysis. We found that chronic nicotine exposure significantly increased infarct size and worsened neurological deficits. In addition, nicotine significantly elevated superoxide levels of cerebral cortex under basal conditions. Transient focal cerebral ischemia produced an increase in superoxide levels of cerebral cortex in control group, but no further increase was found in the nicotine group. Furthermore, chronic nicotine exposure did not alter protein expression of NADPH oxidase but significantly decreased MnSOD and uncoupling protein-2 (UCP-2) in the cerebral cortex and cerebral arteries. Our findings suggest that nicotine-induced exacerbation in brain damage following transient focal cerebral ischemia may be related to a preexisting oxidative stress via decreasing of MnSOD and UCP-2.
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Affiliation(s)
- Chun Li
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana
| | - Hong Sun
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana
| | - Denise M. Arrick
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana
| | - William G. Mayhan
- Department of Cellular Biology and Anatomy, Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Sciences Center-Shreveport, Shreveport, Louisiana
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Zarling JA, Brunt VE, Vallerga AK, Li W, Tao A, Zarling DA, Minson CT. Nitroxide pharmaceutical development for age-related degeneration and disease. Front Genet 2015; 6:325. [PMID: 26594225 PMCID: PMC4635221 DOI: 10.3389/fgene.2015.00325] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 10/19/2015] [Indexed: 02/05/2023] Open
Abstract
Nitroxide small molecule agents are in development as preventative or therapeutic pharmaceutical drugs for age-related macular degeneration (AMD) and cardiovascular disease, which are two major diseases of aging. These aging diseases are associated with patient genetics, smoking, diet, oxidative stress, and chronic inflammation. Nitroxide drugs preventing aging-, smoking-, high sugar or high fat diet-, or radiation- and other environmental-induced pathophysiological conditions in aging disease are reviewed. Tempol (TP), Tempol Hydroxylamine (TP-H), and TP-H prodrug (OT-551) are evaluated in (1) non-smokers versus smokers with cutaneous microvascular dysfunction, rapidly reversed by cutaneous TP; (2) elderly cancer patients at risk for radiation-induced skin burns or hair loss, prevented by topical TP; and (3) elderly smoker or non-smoker AMD patients at risk for vision loss, prevented by daily eye drops of OT-551. The human data indicates safety and efficacy for these nitroxide drugs. Both TP and TP-H topically penetrate and function in skin or mucosa, protecting and treating radiation burns and hair loss or smoking-induced cutaneous vascular dysfunction. TP and TP-H do not penetrate the cornea, while OT-551 does effectively penetrate and travels to the back of the eye, preserving visual acuity and preserving normal and low light luminance in dry AMD smokers and non-smoker patients. Topical, oral, or injectable drug formulations are discussed.
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Affiliation(s)
| | - Vienna E. Brunt
- Department of Human Physiology, University of Oregon, EugeneOR, USA
| | | | - Weixing Li
- Colby Pharmaceutical Company, Menlo ParkCA, USA
| | - Albert Tao
- Department of Biomedical Engineering, Washington University in St. Louis, St. LouisMO, USA
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Nader MA, Gamiel NM, El-Kashef H, Zaghloul MS. Effect of agmatine on experimental vascular endothelial dysfunction. Hum Exp Toxicol 2015; 35:573-82. [PMID: 26424770 DOI: 10.1177/0960327115597311] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This study was designed to investigate the effect of agmatine sulfate (AG, CAS2482-00-0) in nicotine (NIC)-induced vascular endothelial dysfunction (VED) in rabbits. NIC was administered to produce VED in rabbits with or without AG for 6 weeks. Serum lipid profile, serum thiobarbituric acid reactive substances, reduced glutathione, superoxide dismutase generation, serum nitrite/nitrate, serum vascular cellular adhesion molecule-1 (VCAM-1), and aortic nuclear factor κB (NF-κB) levels were analyzed.Treatment with AG markedly improves lipid profile and prevented NIC-induced VED and oxidative stress. The mechanism of AG in improving NIC-induced VED may be due to the significant reduction in serum VCAM-1 levels and aortic NF-κB. Thus, it may be concluded that AG reduces the oxidative stress, nitric oxide production, VCAM-1 levels, and aortic NF-κB expression, thereby consequently improving the integrity of vascular endothelium.
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MESH Headings
- Agmatine/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/pathology
- Aorta, Thoracic/physiopathology
- Cholesterol, HDL/blood
- Cholesterol, LDL/blood
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiopathology
- Glutathione/blood
- Lipid Peroxidation/drug effects
- Male
- Nicotine/toxicity
- Nitric Oxide/blood
- Oxidative Stress/drug effects
- Rabbits
- Superoxide Dismutase/blood
- Triglycerides/blood
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Affiliation(s)
- M A Nader
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Dakahlia Governorate, Egypt Department of Pharmacology and Toxicology, College of Pharmacy, Taibah University, El-Madinah El-Munawarah, Kingdom of Saudi Arabia
| | - N M Gamiel
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Dakahlia Governorate, Egypt
| | - H El-Kashef
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Dakahlia Governorate, Egypt
| | - M S Zaghloul
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Mansoura University, Mansoura, Dakahlia Governorate, Egypt
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9
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NADPH Oxidase Activity in Cerebral Arterioles Is a Key Mediator of Cerebral Small Vessel Disease-Implications for Prevention. Healthcare (Basel) 2015; 3:233-51. [PMID: 27417759 PMCID: PMC4939544 DOI: 10.3390/healthcare3020233] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 03/21/2015] [Accepted: 04/08/2015] [Indexed: 02/05/2023] Open
Abstract
Cerebral small vessel disease (SVD), a common feature of brain aging, is characterized by lacunar infarcts, microbleeds, leukoaraiosis, and a leaky blood-brain barrier. Functionally, it is associated with cognitive decline, dementia, depression, gait abnormalities, and increased risk for stroke. Cerebral arterioles in this syndrome tend to hypertrophy and lose their capacity for adaptive vasodilation. Rodent studies strongly suggest that activation of Nox2-dependent NADPH oxidase activity is a crucial driver of these structural and functional derangements of cerebral arterioles, in part owing to impairment of endothelial nitric oxide synthase (eNOS) activity. This oxidative stress may also contribute to the breakdown of the blood-brain barrier seen in SVD. Hypertension, aging, metabolic syndrome, smoking, hyperglycemia, and elevated homocysteine may promote activation of NADPH oxidase in cerebral arterioles. Inhibition of NADPH oxidase with phycocyanobilin from spirulina, as well as high-dose statin therapy, may have potential for prevention and control of SVD, and high-potassium diets merit study in this regard. Measures which support effective eNOS activity in other ways-exercise training, supplemental citrulline, certain dietary flavonoids (as in cocoa and green tea), and capsaicin, may also improve the function of cerebral arterioles. Asian epidemiology suggests that increased protein intakes may decrease risk for SVD; conceivably, arginine and/or cysteine-which boosts tissue glutathione synthesis, and can be administered as N-acetylcysteine-mediate this benefit. Ameliorating the risk factors for SVD-including hypertension, metabolic syndrome, hyperglycemia, smoking, and elevated homocysteine-also may help to prevent and control this syndrome, although few clinical trials have addressed this issue to date.
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Fujii N, Brunt VE, Minson CT. Tempol improves cutaneous thermal hyperemia through increasing nitric oxide bioavailability in young smokers. Am J Physiol Heart Circ Physiol 2014; 306:H1507-11. [PMID: 24682395 DOI: 10.1152/ajpheart.00886.2013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We recently found that young cigarette smokers display cutaneous vascular dysfunction relative to nonsmokers, which is partially due to reduced nitric oxide (NO) synthase (NOS)-dependent vasodilation. In this study, we tested the hypothesis that reducing oxidative stress improves NO bioavailability, enhancing cutaneous vascular function in young smokers. Ten healthy young male smokers, who had smoked for 6.3 ± 0.7 yr with an average daily consumption of 9.1 ± 0.7 cigarettes, were tested. Cutaneous vascular conductance (CVC) during local heating to 42°C at a rate of 0.1°C/s was evaluated as laser-Doppler flux divided by mean arterial blood pressure and normalized to maximal CVC, induced by local heating to 44°C plus sodium nitroprusside administration. We evaluated plateau CVC during local heating, which is known to be highly dependent on NO, at four intradermal microdialysis sites with 1) Ringer solution (control); 2) 10 μM 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (tempol), a superoxide dismutase mimetic; 3) 10 mM N(ω)-nitro-l-arginine (l-NNA), a nonspecific NOS inhibitor; and 4) a combination of 10 μM tempol and 10 mM l-NNA. Tempol increased plateau CVC compared with the Ringer solution site (90.0 ± 2.3 vs. 77.6 ± 3.9%maximum, P = 0.028). Plateau CVC at the combination site (56.8 ± 4.5%maximum) was lower than the Ringer solution site (P < 0.001) and was not different from the l-NNA site (55.1 ± 4.6%maximum, P = 0.978), indicating the tempol effect was exclusively NO dependent. These data suggest that in young smokers, reducing oxidative stress improves cutaneous thermal hyperemia to local heating by enhancing NO production.
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Affiliation(s)
- Naoto Fujii
- Department of Human Physiology, The University of Oregon, Eugene, Oregon
| | - Vienna E Brunt
- Department of Human Physiology, The University of Oregon, Eugene, Oregon
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11
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Chalouhi N, Ali MS, Starke RM, Jabbour PM, Tjoumakaris SI, Gonzalez LF, Rosenwasser RH, Koch WJ, Dumont AS. Cigarette smoke and inflammation: role in cerebral aneurysm formation and rupture. Mediators Inflamm 2012; 2012:271582. [PMID: 23316103 PMCID: PMC3532877 DOI: 10.1155/2012/271582] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Accepted: 10/27/2012] [Indexed: 12/17/2022] Open
Abstract
Smoking is an established risk factor for subarachnoid hemorrhage yet the underlying mechanisms are largely unknown. Recent data has implicated a role of inflammation in the development of cerebral aneurysms. Inflammation accompanying cigarette smoke exposure may thus be a critical pathway underlying the development, progression, and rupture of cerebral aneurysms. Various constituents of the inflammatory response appear to be involved including adhesion molecules, cytokines, reactive oxygen species, leukocytes, matrix metalloproteinases, and vascular smooth muscle cells. Characterization of the molecular basis of the inflammatory response accompanying cigarette smoke exposure will provide a rational approach for future targeted therapy. In this paper, we review the current body of knowledge implicating cigarette smoke-induced inflammation in cerebral aneurysm formation/rupture and attempt to highlight important avenues for future investigation.
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Affiliation(s)
- Nohra Chalouhi
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Muhammad S. Ali
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Robert M. Starke
- Department of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
| | - Pascal M. Jabbour
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Stavropoula I. Tjoumakaris
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - L. Fernando Gonzalez
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Robert H. Rosenwasser
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Walter J. Koch
- Center for Translational Medicine and George Zallie and Family Laboratory for Cardiovascular Gene Therapy, Department of Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Aaron S. Dumont
- Joseph and Marie Field Cerebrovascular Research Laboratory, Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA
- Division of Neurovascular & Endovascular Surgery, Department of Neurological Surgery, Thomas Jefferson University, 901 Walnut Street, 3rd Floor, Philadelphia, PA 19107, USA
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Shimosato T, Geddawy A, Tawa M, Imamura T, Okamura T. Chronic administration of nicotine-free cigarette smoke extract impaired endothelium-dependent vascular relaxation in rats via increased vascular oxidative stress. J Pharmacol Sci 2012; 118:206-14. [PMID: 22302022 DOI: 10.1254/jphs.11187fp] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Cigarette smoking has been implicated in the initiation and progression of cardiovascular disorders and atherosclerosis. Here, we examined the effects of nicotine-free cigarette smoke extract (CSE) on the regulation of cardiovascular function. Rats were subcutaneously administered PBS or nicotine-free CSE at 0.05 to 1.5 mL/day per rat for 4 weeks. Blood pressure, cardiac function, and vascular responsiveness were measured at 4 weeks after administration. Furthermore, acute effects of nicotine-free CSE were also studied in the aorta isolated from normal rats. Blood pressure and left ventricular systolic pressure (LVSP) were significantly increased in the nicotine-free CSE-administered rats, but heart rate, dP/dt(max), and dP/dt(min) were not affected. Endothelium-dependent relaxation by acetylcholine (ACh) in the nicotine-free CSE-treated rats was significantly attenuated compared to PBS-treated rats, but endothelium-independent relaxation by sodium nitroprusside (SNP) did not differ. Pretreatment with superoxide dismutase restored the attenuated ACh-induced relaxation. Contractions by phenylephrine, angiotensin II, and KCl did not differ between two groups. In vitro acute nicotine-free CSE treatment did not alter the response to ACh or SNP. These results suggest that chronic nicotine-free CSE administration impairs endothelial function by increased production of superoxide derived from the vascular wall components other than smooth muscles and induces slight hypertension accompanied with LVSP elevation.
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Affiliation(s)
- Takashi Shimosato
- Department of Pharmacology, Shiga University of Medical Science, Seta, Otsu, Shiga 520-2192; Research Department, NISSEI BILIS Co. Ltd., Minakuchi, Koka, Shiga 528-0052, Japan
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13
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El-Seweidy MM, Mohamed HE, Asker ME, Atteia HH. Nicotine and vascular endothelial dysfunction in female ovariectomized rats: role of estrogen replacement therapy. J Pharm Pharmacol 2011; 64:108-19. [PMID: 22150678 DOI: 10.1111/j.2042-7158.2011.01377.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES The protective effects of estrogen replacement therapy (ERT) against oxidative injury and endothelial dysfunction in the aortic tissues induced with nicotine in ovariectomized (OVX) rats were investigated. METHODS Female rats were divided into a sham-operated group (n = 8) and four groups in which OVX rats received either vehicle (0.1 ml sesame oil, i.m., n = 8), or nicotine (0.1 mg/kg, s.c., n = 8), or estradiol benzoate (0.1 mg/kg, i.m., n = 8), or both nicotine and estradiol benzoate (n = 8) starting at week 5 after the surgery and continuing for the following 6 weeks. KEY FINDINGS ERT was effective in preventing the rise in plasma lipid profile, atherogenic index and the level of induced endothelin-1 (ET-1) in nicotine-treated OVX rats. It also reduced aortic malondialdehyde, hydroxyproline levels, calcium content and caspase-3 expression induced in nicotine-treated OVX rats. ERT increased serum estradiol, high-density lipoprotein cholesterol and nitric oxide levels in nicotine-treated OVX rats. Furthermore, ERT was effective in restoring reduced glutathione and cyclic guanosine monophosphate contents and endothelial nitric oxide synthase expression in aortic tissues of nicotine-treated OVX rats. CONCLUSIONS Short-term ERT could be a promising therapeutic strategy to minimize nicotine-induced oxidative stress and vascular endothelial dysfunction in menopausal women subjected to environmental smoke.
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Affiliation(s)
- Mohamed M El-Seweidy
- Department of Biochemistry, Faculty of Pharmacy, University of Zagazig, Zagazig, Egypt
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14
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Chakkarwar VA. Fenofibrate attenuates nicotine-induced vascular endothelial dysfunction in the rat. Vascul Pharmacol 2011; 55:163-8. [PMID: 21864717 DOI: 10.1016/j.vph.2011.08.215] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 07/31/2011] [Accepted: 08/08/2011] [Indexed: 12/23/2022]
Abstract
The study has been designed to investigate the effect of fenofibrate on nicotine-induced vascular endothelial dysfunction (VED) in rats. Nicotine (2 mg/kg/day, i.p., 4 weeks) was administered to produce VED in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum and aortic concentration of nitrite/nitrate. Further, the integrity of vascular endothelium was assessed using the scanning electron microscopy of thoracic aorta. The expression of mRNA for p22phox and eNOS was assessed by using reverse transcriptase-polymerase chain reaction. Serum thiobarbituric acid reactive substances concentration (TBARS) and aortic superoxide anion concentration were estimated to assess oxidative stress. Moreover, the serum lipid profile was assessed by estimating serum cholesterol, triglycerides and high density lipoprotein. The administration of nicotine induces VED by increased oxidative stress, altered lipid profile and impaired the integrity of vascular endothelium as assessed in terms of decrease in expression of mRNA for endothelial nitric oxide synthase (eNOS), impairing the integrity of vascular endothelium and subsequently decreasing serum and aortic nitrite/nitrate and attenuating acetylcholine-induced endothelium dependent relaxation. Further, nicotine produced oxidative stress, assessed in terms of increase in serum TBARS and aortic superoxide anion generation and increase in expression of mRNA for p22phox. Nicotine altered the lipid profile by increasing the serum cholesterol, triglycerides and decreasing the high density lipoprotein. However, treatment with fenofibrate (32 mg/kg, p.o.) markedly prevented nicotine-induced VED by decreasing oxidative stress and improving integrity of vascular endothelium, normalising the altered lipid profile, increasing the concentration of serum and aortic nitrite/nitrate, enhancing the acetylcholine-induced endothelium dependent relaxation and decreasing serum TBARS and aortic superoxide anion generation. Thus, it may be concluded that fenofibrate has vascular protecting potential, by improving the integrity and function of vascular endothelium.
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Affiliation(s)
- Vishal Arvind Chakkarwar
- Cardiovascular Pharmacology Division, I.S.F. Institute of Pharmaceutical Sciences and Drug Research, Moga 142 001, India.
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Thompson LP, Liu H, Evans L, Mong JA. Prenatal nicotine increases matrix metalloproteinase 2 (MMP-2) expression in fetal guinea pig hearts. Reprod Sci 2011; 18:1103-10. [PMID: 21775771 DOI: 10.1177/1933719111404605] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This study tested the hypothesis that maternal nicotine ingestion increases matrix metalloproteinase (MMP) expression in fetal hearts, which is mediated by the generation of reactive oxygen species. Timed pregnant guinea pigs were administered either water alone, nicotine (200 μg/mL), N-acetylcysteine (NAC), or nicotine plus NAC in their drinking water for 10 days at 52-day gestation (term = 65 days). Near-term (62 days), anesthetized fetuses were extracted, hearts were excised, and left cardiac ventricles snap frozen for analysis of MMP-2/-9/-13 protein and activity levels. Interstitial collagens were identified by Picrosirius red stain to assess changes in the extracellular matrix. Prenatal nicotine increased active MMP-2 forms and interstitial collagen but had no effect on either pro- or active MMP-9 or MMP-13 forms. In the presence of nicotine, NAC decreased active MMP-2 protein levels and reversed the nicotine-induced increase in collagen staining. We conclude that prenatal nicotine alters MMP-2 expression in fetal hearts that may be mediated by reactive oxygen species generation.
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Affiliation(s)
- Loren P Thompson
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland, Baltimore, MD 21201, USA.
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Park HS, Cho K, Park YJ, Lee T. Chronic nicotine exposure attenuates proangiogenic activity on human umbilical vein endothelial cells. J Cardiovasc Pharmacol 2011; 57:287-93. [PMID: 21383590 DOI: 10.1097/fjc.0b013e318206b5d9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The pathogenic mechanism of nicotine, a major product of smoking, on vascular endothelial cells is not well defined yet. The purpose of this study was to determine whether chronic exposure to nicotine alters angiogenic activity in human umbilical vein endothelial cells and to identify a potential role for endothelial nitric oxide synthase (eNOS) expression. Our study demonstrated that acute nicotine treatment enhanced nitric oxide release, eNOS activation, and proangiogenic activity. However, chronic nicotine exposure impaired proangiogenic function (decreased cell migration and tubular structure formation) in human umbilical vein endothelial cells compared with acute exposure, but sustained the antiapoptotic effect. These findings seem to be related to eNOS gene expression and nitric oxide production, which may be involved in the pathophysiology of chronic nicotine addicts.
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Affiliation(s)
- Hyung Sub Park
- Department of Surgery, Seoul National University College of Medicine, Seoul, Korea
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17
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Toda N, Toda H. Nitric oxide-mediated blood flow regulation as affected by smoking and nicotine. Eur J Pharmacol 2010; 649:1-13. [PMID: 20868673 DOI: 10.1016/j.ejphar.2010.09.042] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 08/01/2010] [Accepted: 09/14/2010] [Indexed: 12/15/2022]
Abstract
Cigarette smoking is a major risk factor for atherosclerosis, cerebral and coronary vascular diseases, hypertension, and diabetes mellitus. Chronic smoking impairs endothelial function by decreasing the formation of nitric oxide and increasing the degradation of nitric oxide via generation of oxygen free radicals. Nitric oxide liberated from efferent nitrergic nerves is also involved in vasodilatation, increased regional blood flow, and hypotension that are impaired through nitric oxide sequestering by smoking-induced factors. Influence of smoking on nitric oxide-induced blood flow regulation is not necessarily the same in all organs and tissues. However, human studies are limited mainly to the forearm blood flow measurement that assesses endothelial function under basal and stimulated conditions and also determination of penile tumescence and erection in response to endothelial and neuronal nitric oxide. Therefore, information about blood flow regulation in other organs, such as the brain and placenta, has been provided mainly from studies on experimental animals. Nicotine, a major constituent of cigarette smoke, acutely dilates cerebral arteries and arterioles through nitric oxide liberated from nitrergic neurons, but chronically interferes with endothelial function in various vasculatures, both being noted in studies on experimental animals. Cigarette smoke constituents other than nicotine also have some vascular actions. Not only active but also passive smoking is undoubtedly harmful for both the smokers themselves and their neighbors, who should bear in mind that they can face serious diseases in the future, which may result in lengthy hospitalization, and a shortened lifespan.
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Affiliation(s)
- Noboru Toda
- Toyama Institute for Cardiovascular Research, 7-13, 1-Chome, Azuchi-machi, Chuo-ku, Osaka 541-0052, Japan.
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18
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Mayhan WG, Arrick DM, Sun H, Patel KP. Exercise training restores impaired dilator responses of cerebral arterioles during chronic exposure to nicotine. J Appl Physiol (1985) 2010; 109:1109-14. [PMID: 20705948 DOI: 10.1152/japplphysiol.00564.2010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our goal was to determine whether exercise training (ExT) alleviates impaired nitric oxide synthase (NOS)-dependent dilation of pial arterioles during chronic exposure to nicotine. We measured dilation of cerebral (pial) arterioles in sedentary and exercised control and nicotine-treated (2 mg·kg(-1)·day(-1) for 4 wk via an osmotic minipump) rats to an endothelial NOS (eNOS)-dependent (ADP), a neuronal NOS (nNOS)-dependent [N-methyl-D-aspartic acid (NMDA)], and a NOS-independent (nitroglycerin) agonist. In addition, we harvested brain tissue from sedentary and exercised control and nicotine-treated rats to measure the production of superoxide anion and measured superoxide dismutase-1 (SOD-1) protein in cerebral microvessels using Western blot. We found that eNOS-and nNOS-dependent, but not NOS-independent, vasodilation was impaired in nicotine-treated compared with control rats. In addition, the production of superoxide anion (lucigenin chemiluminescence) was increased, and SOD-1 protein decreased, in rats treated with nicotine compared with control rats. Further, although ExT did not significantly affect eNOS- or nNOS-dependent vasodilation in control rats, ExT restored impaired eNOS- and nNOS-dependent responses in nicotine-treated rats. In addition, the increase in superoxide anion production observed in nicotine-treated rats was reduced by ExT, and SOD-1 protein was increased in nicotine-treated rats by ExT. We suggest that ExT restores impaired NOS-dependent dilation of pial arterioles during chronic exposure to nicotine by a mechanism related to the formation of superoxide anion.
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Affiliation(s)
- William G Mayhan
- Dept. of Cellular and Integrative Physiology, 985850 Nebraska Medical Center, Omaha, NE 68198-5850, USA.
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Kaur J, Reddy K, Balakumar P. The Novel Role of Fenofibrate in Preventing Nicotine- and Sodium Arsenite-Induced Vascular Endothelial Dysfunction in the Rat. Cardiovasc Toxicol 2010; 10:227-38. [DOI: 10.1007/s12012-010-9086-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Moriguchi M, Yamada M, Miake Y, Yanagisawa T. Transforming growth factor β inducible apoptotic cascade in epithelial cells during rat molar tooth eruptions. Anat Sci Int 2009; 85:92-101. [PMID: 19779767 DOI: 10.1007/s12565-009-0061-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2009] [Accepted: 08/21/2009] [Indexed: 02/01/2023]
Abstract
In tooth eruptions, the presence of apoptotic epithelial cells at the eruption site has been reported, but the factors that induce apoptosis in these cells remain to be elucidated, as do the induction pathways. In this study, we focused our attention on transforming growth factor beta (TGF-beta), which is known to induce apoptosis during embryonic development. Oral epithelium and dental lamina of maxillary first molars in 8- and 15-day-old rats were used to investigate the induction pathway of apoptosis by performing the immunohistochemical tests outlined below and assessing the characteristics of cells that undergo apoptosis by transmission electron microscopy in rats 8 and 15 days after birth. We examined TGF-beta-receptor 1, TGF-beta inducible transcription factor 1 (TIEG1), NADPHoxidase 4 (Nox4), cytochrome c, caspase-3 (active form and pro-enzyme), apoptosis-inducing protein Daxx, apoptosis signal-regulating kinase 1 (ASK1), glycogen synthase kinase-3 beta phosphorylated on serine 9 (p-GSK-3beta), and beta-catenin. We also performed periodic acid Schiff (PAS) reaction and terminal deoxynucleotidyl transferase-mediated dUTD nick end labeling (TUNEL) staining. At eruption sites 8 days after birth, reactions to TGF-beta-receptor 1, TIEG1, Nox4, cytochrome c, caspase-3, p-GSK-3beta, and beta-catenin, and PAS-positive cells were observed in areas close to the basal layer of oral epithelium through to the center of the dental lamina, but no reaction to Daxx or ASK1 was noted at these sites. Electron microscopy revealed the accumulation of glycogen granules in the cells that showed reactions to the above-mentioned markers as well as in the spaces among them. In the rats 15 days after birth (immediately before tooth eruption), the PAS-positive cells that showed reactions to the above antibodies remained on the buccal side of the epithelium, and high-electron-density apoptotic bodies and TUNEL-positive bodies were noted. Therefore, during tooth eruption, TGF-beta may induce apoptosis of cells rich in glycogen granules, and cytochrome c and caspase-3 may function to induce apoptosis. In addition, reactive oxygen species may be involved in this induction pathway via TIEG1 and Nox4 without involvement of Daxx and ASK1. Moreover, overexpression of p-GSK-3beta and beta-catenin may also contribute to apoptosis of oral epithelium at the eruption site and dental lamina cells. Glycogen storage mediated by p-GSK-3beta and crosstalk between the TGF-beta and Wnt signaling pathways may participate in the formation of tooth eruption passage.
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Affiliation(s)
- Mitsuko Moriguchi
- Department of Ultrastructural Science, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba, 261-8502, Japan.
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Mayhan WG, Arrick DM, Sharpe GM, Sun H. Nitric oxide synthase-dependent responses of the basilar artery during acute infusion of nicotine. Nicotine Tob Res 2009; 11:270-7. [PMID: 19246430 DOI: 10.1093/ntr/ntn025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Our goals were to determine whether acute exposure to nicotine alters nitric oxide synthase (NOS)-dependent responses of the basilar artery and to identify a potential role for activation of NAD(P)H oxidase in nicotine-induced impairment in NOS-dependent responses of the basilar artery. METHODS We measured in vivo diameter of the basilar artery in response to NOS-dependent (acetylcholine) and NOS-independent (nitroglycerin) agonists before and during an acute infusion of nicotine (2 microg/kg/min intravenously for 30 min followed by a maintenance dose of 0.35 microg/kg/min). In addition, we measured superoxide anion production (lucigenin chemiluminescence) by the basilar artery in response to nicotine in the absence or presence of apocynin. RESULTS We found that NOS-dependent, but not NOS-independent, vasodilation was impaired during infusion of nicotine. In addition, treatment of the basilar artery with apocynin (100 microM, 30 min prior to infusion of nicotine) prevented nicotine-induced impairment in NOS-dependent vasodilation. Further, the production of superoxide anion was increased in the basilar artery by nicotine, and this increase could be inhibited by apocynin. DISCUSSION Our findings suggest that acute exposure to nicotine impairs NOS-dependent dilation of the basilar artery by a mechanism that appears to be related to the release of superoxide anion. A possible source of superoxide may be via the activation of NAD(P)H oxidase.
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Affiliation(s)
- William G Mayhan
- Department of Cellular and Integrative Physiology, 985850 Nebraska Medical Center, Omaha, NE 68198-5850, USA.
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Chrissobolis S, Faraci FM. The role of oxidative stress and NADPH oxidase in cerebrovascular disease. Trends Mol Med 2008; 14:495-502. [PMID: 18929509 DOI: 10.1016/j.molmed.2008.09.003] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 09/01/2008] [Accepted: 09/01/2008] [Indexed: 02/07/2023]
Abstract
The study of reactive oxygen species (ROS) and oxidative stress remains a very active area of biological research, particularly in relation to cellular signaling and the role of ROS in disease. In the cerebral circulation, oxidative stress occurs in diverse forms of disease and with aging. Within the vessel wall, ROS produce complex structural and functional changes that have broad implications for regulation of cerebral perfusion and permeability of the blood-brain barrier. These oxidative-stress-induced changes are thought to contribute to the progression of cerebrovascular disease. Here, we highlight recent findings in relation to oxidative stress in the cerebral vasculature, with an emphasis on the emerging role for NADPH oxidases as a source of ROS and the role of ROS in models of disease.
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Affiliation(s)
- Sophocles Chrissobolis
- Departments of Internal Medicine and Pharmacology, Division of Cardiovascular Diseases, Cardiovascular Center, University of Iowa, Carver College of Medicine, Iowa City, IA 52242, USA
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Fabian RH, Perez-Polo JR, Kent TA. Perivascular nitric oxide and superoxide in neonatal cerebral hypoxia-ischemia. Am J Physiol Heart Circ Physiol 2008; 295:H1809-14. [PMID: 18676689 PMCID: PMC2593505 DOI: 10.1152/ajpheart.00301.2007] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Accepted: 07/28/2008] [Indexed: 11/22/2022]
Abstract
Decreased cerebral blood flow (CBF) has been observed following the resuscitation from neonatal hypoxic-ischemic injury, but its mechanism is not known. We address the hypothesis that reduced CBF is due to a change in nitric oxide (NO) and superoxide anion O(2)(-) balance secondary to endothelial NO synthase (eNOS) uncoupling with vascular injury. Wistar rats (7 day old) were subjected to cerebral hypoxia-ischemia by unilateral carotid occlusion under isoflurane anesthesia followed by hypoxia with hyperoxic or normoxic resuscitation. Expired CO(2) was determined during the period of hyperoxic or normoxic resuscitation. Laser-Doppler flowmetry was used with isoflurane anesthesia to monitor CBF, and cerebral perivascular NO and O(2)(-) were determined using fluorescent dyes with fluorescence microscopy. The effect of tetrahydrobiopterin supplementation on each of these measurements and the effect of apocynin and N(omega)-nitro-L-arginine methyl ester (L-NAME) administration on NO and O(2)(-) were determined. As a result, CBF in the ischemic cortex declined following the onset of resuscitation with 100% O(2) (hyperoxic resuscitation) but not room air (normoxic resuscitation). Expired CO(2) was decreased at the onset of resuscitation, but recovery was the same in normoxic and hyperoxic resuscitated groups. Perivascular NO-induced fluorescence intensity declined, and O(2)(-)-induced fluorescence increased in the ischemic cortex after hyperoxic resuscitation up to 24 h postischemia. L-NAME treatment reduced O(2)(-) relative to the nonischemic cortex. Apocynin treatment increased NO and reduced O(2)(-) relative to the nonischemic cortex. The administration of tetrahydrobiopterin following the injury increased perivascular NO, reduced perivascular O(2)(-), and increased CBF during hyperoxic resuscitation. These results demonstrate that reduced CBF follows hyperoxic resuscitation but not normoxic resuscitation after neonatal hypoxic-ischemic injury, accompanied by a reduction in perivascular production of NO and an increase in O(2)(-). The finding that tetrahydrobiopterin, apocynin, and L-NAME normalized radical production suggests that the uncoupling of perivascular NOS, probably eNOS, due to acquired relative tetrahydrobiopterin deficiency occurs after neonatal hypoxic-ischemic brain injury. It appears that both NOS uncoupling and the activation of NADPH oxidase participate in the changes of reactive oxygen concentrations seen in cerebral hypoxic-ischemic injury.
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MESH Headings
- Acetophenones/pharmacology
- Animals
- Animals, Newborn
- Biopterins/analogs & derivatives
- Biopterins/pharmacology
- Carbon Dioxide/metabolism
- Cerebral Cortex/blood supply
- Cerebrovascular Circulation/drug effects
- Disease Models, Animal
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Enzyme Inhibitors/pharmacology
- Exhalation
- Hypoxia-Ischemia, Brain/metabolism
- Hypoxia-Ischemia, Brain/pathology
- Hypoxia-Ischemia, Brain/physiopathology
- Hypoxia-Ischemia, Brain/therapy
- Laser-Doppler Flowmetry
- Microscopy, Fluorescence
- NADPH Oxidases/antagonists & inhibitors
- NADPH Oxidases/metabolism
- NG-Nitroarginine Methyl Ester/pharmacology
- Nitric Oxide/metabolism
- Nitric Oxide Synthase Type II/antagonists & inhibitors
- Nitric Oxide Synthase Type II/metabolism
- Nitric Oxide Synthase Type III/antagonists & inhibitors
- Nitric Oxide Synthase Type III/metabolism
- Oxygen Inhalation Therapy/adverse effects
- Rats
- Rats, Wistar
- Resuscitation/adverse effects
- Superoxides/metabolism
- Time Factors
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Affiliation(s)
- Roderic H Fabian
- Department of Neurology, Baylor College of Medicine and the Michael E. DeBakey Veterans Affairs Medical Center Stroke Program, Houston 77030, USA.
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Iida H, Iida M, Takenaka M, Fukuoka N, Dohi S. Rho-kinase inhibitor and Nicotinamide Adenine Dinucleotide PHosphate oxidase inhibitor prevent impairment of endothelium-dependent cerebral vasodilation by acute cigarette smoking in rats. J Renin Angiotensin Aldosterone Syst 2008; 9:89-94. [DOI: 10.3317/jraas.2008.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Introduction. We previously reported that acute cigarette smoking can cause a dysfunction of endothelium-dependent vasodilation in cerebral vessels, and that blocking the angiotensin II (Ang II) type 1 (AT1) receptor with valsartan prevented this impairment. Our aim was to investigate the effects of a Rho-kinase inhibitor (fasudil) and a Nicotinamide Adenine Dinucleotide PHosphate (NADPH) oxidase inhibitor (apocynin) on smoking-induced endothelial dysfunction in cerebral arterioles. Method. In Sprague—Dawley rats, we used a closed cranial window preparation to measure changes in pial vessel diameters following topical acetylcholine (ACh) before smoking. After one-minute smoking, we again examined the arteriolar responses to ACh. Finally, after intravenous fasudil or apocynin pre-treatment we re-examined the vasodilator responses to topical ACh (before and after cigarette smoking). Results. Under control conditions, cerebral arterioles were dose-dependently dilated by topical ACh (10-6 M and 10-5 M). One hour after a one-minute smoking (1 mg-nicotine cigarette), 10-5 M ACh constricted cerebral arterioles. However, one hour after a one-minute smoking, 10-5 M ACh dilated cerebral pial arteries both in the fasudil pre-treatment and the apocynin pre-treatment groups, responses that were significantly different from those obtained without fasudil or apocynin pre-treatment. Conclusion. Thus, inhibition of Rho-kinase and NADPH oxidase activities may prevent the above smoking-induced impairment of endothelium-dependent vasodilation.
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Affiliation(s)
- Hiroki Iida
- Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, Gifu-City, Japan,
| | - Mami Iida
- 2nd Department of Internal Medicine (Cardiology) and Anesthesiology, Gifu University Graduate School of Medicine, Gifu-City, Japan
| | - Motoyasu Takenaka
- Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, Gifu-City, Japan
| | - Naokazu Fukuoka
- Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, Gifu-City, Japan
| | - Shuji Dohi
- Department of Anesthesiology and Pain Medicine, Gifu University Graduate School of Medicine, Gifu-City, Japan
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Park L, Anrather J, Girouard H, Zhou P, Iadecola C. Nox2-derived reactive oxygen species mediate neurovascular dysregulation in the aging mouse brain. J Cereb Blood Flow Metab 2007; 27:1908-18. [PMID: 17429347 DOI: 10.1038/sj.jcbfm.9600491] [Citation(s) in RCA: 209] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Aging is associated with cerebrovascular dysregulation, which may underlie the increased susceptibility to ischemic stroke and vascular cognitive impairment occurring in the elder individuals. Although it has long been known that oxidative stress is responsible for the cerebrovascular dysfunction, the enzymatic system(s) generating the reactive oxygen species (ROS) have not been identified. In this study, we investigated whether the superoxide-producing enzyme NADPH oxidase is involved in alterations of neurovascular regulation induced by aging. Cerebral blood flow (CBF) was recorded by laser-Doppler flowmetry in anesthetized C57BL/6 mice equipped with a cranial window (age=3, 12, and 24 months). In 12-month-old mice, the CBF increases evoked by whisker stimulation or by the endothelium-dependent vasodilators acetylcholine and bradykinin were attenuated by 42, 36, and 53%, respectively (P<0.05). In contrast, responses to the nitric oxide donor S-nitroso-D-penicillamine or adenosine were not attenuated (P>0.05). These cerebrovascular effects were associated with increased production of ROS in neurons and cerebral blood vessels, assessed by hydroethidine microfluorography. The cerebrovascular impairment present in 12-month-old mice was reversed by the ROS scavenger Mn (III) tetrakis (4-benzoic acid) porphyrin chloride or by the NADPH oxidase peptide inhibitor gp91ds-tat, and was not observed in mice lacking the Nox2 subunit of NADPH oxidase. These findings establish Nox2 as a critical source of the neurovascular oxidative stress mediating the deleterious cerebrovascular effects associated with increasing age.
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Affiliation(s)
- Laibaik Park
- Division of Neurobiology, Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, New York 10021, USA
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The polymorphonuclear leukocyte contributes to the development of hypertension in the Sabra rat. J Hypertens 2007; 25:2249-56. [DOI: 10.1097/hjh.0b013e3282dd79b6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Arrick DM, Mayhan WG. Acute infusion of nicotine impairs nNOS-dependent reactivity of cerebral arterioles via an increase in oxidative stress. J Appl Physiol (1985) 2007; 103:2062-7. [PMID: 17901243 DOI: 10.1152/japplphysiol.00411.2007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our goals were to determine whether acute exposure to nicotine alters neuronal nitric oxide synthase (nNOS)-dependent reactivity of cerebral arterioles and to identify a potential role for oxidative stress in nicotine-induced impairment in nNOS-dependent responses of cerebral arterioles. We measured in vivo diameter of cerebral arterioles to nNOS-dependent (N-methyl-d-aspartate and kainate) and -independent (nitroglycerin) agonists before and during acute treatment with nicotine. We found that nNOS-dependent, but not -independent, vasodilatation was impaired during treatment with nicotine. In addition, treatment of the cerebral microcirculation with tempol (1 h before infusion of nicotine) prevented nicotine-induced impairment in nNOS-dependent vasodilatation. Furthermore, the production of superoxide anion (lucigenin chemiluminescence) was increased in parietal cortex tissue of rats by treatment with nicotine, and this increase in superoxide anion production could be inhibited by tempol. Our findings suggest that acute exposure to nicotine impairs nNOS-dependent dilatation of cerebral arterioles by a mechanism that appears to be related to the formation of superoxide anion.
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Affiliation(s)
- Denise M Arrick
- Department of Cellular and Integrative Physiology, Omaha, NE 68198-5850, USA
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McCarty MF. ''Iatrogenic Gilbert syndrome''--a strategy for reducing vascular and cancer risk by increasing plasma unconjugated bilirubin. Med Hypotheses 2007; 69:974-94. [PMID: 17825497 DOI: 10.1016/j.mehy.2006.12.069] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 12/18/2006] [Indexed: 01/11/2023]
Abstract
The catabolism of heme, generating biliverdin, carbon monoxide, and free iron, is mediated by heme oxygenase (HO). One form of this of this enzyme, heme oxygenase-1, is inducible by numerous agents which promote oxidative stress, and is now known to provide important antioxidant protection, as demonstrated in many rodent models of free radical-mediated pathogenesis, and suggested by epidemiology observing favorable health outcomes in individuals carrying high-expression alleles of the HO-1 gene. The antioxidant impact of HO-1 appears to be mediated by bilirubin, generated rapidly from biliverdin by ubiquitously expressed biliverdin reductase. Bilirubin efficiently scavenges a wide range of physiological oxidants by electron donation. In the process, it is often reconverted to biliverdin, but biliverdin reductase quickly regenerates bilirubin, thereby greatly boosting its antioxidant potential. There is also suggestive evidence that bilirubin inhibits the activity or activation of NADPH oxidase. Increased serum bilirubin is associated with reduced risk for atherogenic disease in epidemiological studies, and more limited data show an inverse correlation between serum bilirubin and cancer risk. Gilbert syndrome, a genetic variant characterized by moderate hyperbilirubinemia attributable to reduced hepatic expression of the UDP-glucuronosyltransferase which conjugates bilirubin, has been associated with a greatly reduced risk for ischemic heart disease and hypertension in a recent study. Feasible strategies for boosting serum bilirubin levels may include administration of HO-1 inducers, supplementation with bilirubin or biliverdin, and administration of drugs which decrease the efficiency of hepatic bilirubin conjugation. The well-tolerated uricosuric drug probenecid achieves non-competitive inhibition of hepatic glucuronidation reactions by inhibiting the transport of UDP-glucuronic acid into endoplasmic reticulum; probenecid therapy is included in the differential diagnosis of hyperbilirubinemia, and presumably could be used to induce an ''iatrogenic Gilbert syndrome''. Other drugs, such as rifampin, can raise serum bilirubin through competitive inhibition of hepatocyte bilirubin uptake--although unfortunately rifampin is not as safe as probenecid. Measures which can safely achieve moderate serum elevations of bilirubin may prove to have value in the prevention and/or treatment of a wide range of disorders in which oxidants play a prominent pathogenic role, including many vascular diseases, cancer, and inflammatory syndromes. Phycobilins, algal biliverdin metabolites that are good substrates for biliverdin reductase, may prove to have clinical antioxidant potential comparable to that of bilirubin.
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Talman WT, Nitschke Dragon D. Neuronal nitric oxide mediates cerebral vasodilatation during acute hypertension. Brain Res 2007; 1139:126-32. [PMID: 17291465 PMCID: PMC1885240 DOI: 10.1016/j.brainres.2007.01.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 10/09/2006] [Accepted: 10/16/2006] [Indexed: 12/21/2022]
Abstract
Parasympathetic nerves from the pterygopalatine ganglia provide nitroxidergic innervation to forebrain cerebral blood vessels. Disruption of that innervation attenuates cerebral vasodilatation seen during acute hypertension as does systemic administration of a non-selective nitric oxide synthase (NOS) inhibitor. Although such studies suggest that nitric oxide (NO) released from parasympathetic nerves participates in vasodilatation of cerebral vessels during hypertension, that hypothesis has not been tested with selective local inhibition of neuronal NOS (nNOS). We tested that hypothesis through these studies performed in anesthetized rats instrumented for continuous measurement of blood pressure, heart rate and pial arterial diameter through a cranial window. We sought to determine if the nNOS inhibitor propyl-L-arginine delivered directly to the outer surface of a pial artery would (1) attenuate changes in pial arterial diameter during acute hypertension and (2) block nNOS-mediated dilator effects of N-methyl-D-aspartate (NMDA) delivered into the window but (3) not block vasodilatation elicited by acetylcholine (ACh) and mediated by endothelial NOS dilator. Without the nNOS inhibitor arterial diameter abruptly increased 70+/-15% when mean arterial pressure (MAP) reached 183+/-3 mm Hg while with nNOS inhibition diameter increased only 13+/-10% (p<0.05) even when MAP reached 191+/-4 mm Hg (p>0.05). The nNOS inhibitor significantly attenuated vasodilatation induced by NMDA but not ACh delivered into the window. Thus, local nNOS inhibition attenuates breakthrough from autoregulation during hypertension as does complete interruption of the parasympathetic innervation of cerebral vessels. These findings further support the hypothesis that NO released from parasympathetic fibers contributes to cerebral vasodilatation during acute hypertension.
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Affiliation(s)
- William T Talman
- Laboratory of Neurobiology, Department of Neurology, VAHCS, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.
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Hotston MR, Jeremy JY, Bloor J, Koupparis A, Persad R, Shukla N. Sildenafil inhibits the up-regulation of phosphodiesterase type 5 elicited with nicotine and tumour necrosis factor-alpha in cavernosal vascular smooth muscle cells: mediation by superoxide. BJU Int 2006; 99:612-8. [PMID: 17176295 DOI: 10.1111/j.1464-410x.2006.06618.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To determine whether there is an association between vascular phosphodiesterase type 5 (PDE-5) and NADPH oxidase (NOX) in cavernosal vascular smooth muscle cells (CVSMCs), and to study the actions of the PDE-5 inhibitor sildenafil; the pro-erectile actions of nitric oxide (NO) are reduced by PDE-5 which hydrolyses cGMP to inactive GMP, thus an up-regulation of PDE-5 and over-production of O(2)(-) derived from NOX might promote erectile dysfunction (ED). MATERIALS AND METHODS To study the effects of nicotine and tumour necrosis factor-alpha (TNF-alpha) on superoxide (O(2)(-)) production and PDE-5 expression, CVSMCs from rabbit penis were incubated with nicotine or TNF-alpha, and superoxide dismutase (SOD), catalase, sildenafil citrate, or apocynin (NADPH inhibitor) for 16 h. The expression of PDE-5 and of glyceraldehyde-3-phosphate dehydrogenase (internal standard) was assessed using Western blotting. O(2)(-) was measured spectrophotometrically. RESULTS After a 16-h incubation, both nicotine (maximal at 10 microm) and TNF-alpha (10 ng/mL) significantly increased O(2)(-) formation in CVSMCs; this effect was blocked by co-incubating with SOD, catalase, and sildenafil (1 microm). Apocynin also inhibited O(2)(-) formation when added after 16-h incubation with nicotine (10 microm) or TNF-alpha. PDE-5 expression was also significantly increased in CVSMCs incubated with nicotine and TNF-alpha. This effect was negated by 16-h co-incubation with SOD, catalase, apocynin, and sildenafil. CONCLUSIONS Nicotine and TNF-alpha up-regulate PDE-5 expression in CVSMCs through an a priori up-regulation of NOX and formation of O(2)(-). As PDE-5 hydrolyses cGMP, this effect might 'blunt' the pro-erectile actions of NO. Sildenafil inhibits O(2)(-) formation, and 'normalizes' PDE-5 expression. This represents a novel pathogenic mechanism underlying ED, and a novel mechanism of action of sildenafil.
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Quinn MT, Ammons MCB, Deleo FR. The expanding role of NADPH oxidases in health and disease: no longer just agents of death and destruction. Clin Sci (Lond) 2006; 111:1-20. [PMID: 16764554 DOI: 10.1042/cs20060059] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The NADPH oxidase was originally identified as a key component of human innate host defence. In phagocytes, this enzyme complex is activated to produce superoxide anion and other secondarily derived ROS (reactive oxygen species), which promote killing of invading micro-organisms. However, it is now well-established that NADPH oxidase and related enzymes also participate in important cellular processes not directly related to host defence, including signal transduction, cell proliferation and apoptosis. These enzymes are present in essentially every organ system in the body and contribute to a multitude of physiological events. Although essential for human health, excess NADPH-oxidase-generated ROS can promote numerous pathological conditions. Herein, we summarize our current understanding of NADPH oxidases and provide an overview of how they contribute to specific human diseases.
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Affiliation(s)
- Mark T Quinn
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717, USA.
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