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Tran AN, Boyd NH, Walker K, Hjelmeland AB. NOS Expression and NO Function in Glioma and Implications for Patient Therapies. Antioxid Redox Signal 2017; 26:986-999. [PMID: 27411305 PMCID: PMC5467121 DOI: 10.1089/ars.2016.6820] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
SIGNIFICANCE Gliomas are central nervous system tumors that primarily occur in the brain and arise from glial cells. Gliomas include the most common malignant brain tumor in adults known as grade IV astrocytoma, or glioblastoma (GBM). GBM is a deadly disease for which the most significant advances in treatment offer an improvement in survival of only ∼2 months. CRITICAL ISSUES To develop novel treatments and improve patient outcomes, we and others have sought to determine the role of molecular signals in gliomas. Recent Advances: One signaling molecule that mediates important biologies in glioma is the free radical nitric oxide (NO). In glioma cells and the tumor microenvironment, NO is produced by three isoforms of nitric oxide synthase (NOS), NOS1, NOS2, and NOS3. NO and NOS affect glioma growth, invasion, angiogenesis, immunosuppression, differentiation state, and therapeutic resistance. FUTURE DIRECTIONS These multifaceted effects of NO and NOS on gliomas both in vitro and in vivo suggest the potential of modulating the pathway for antiglioma patient therapies. Antioxid. Redox Signal. 26, 986-999.
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Affiliation(s)
- Anh N Tran
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Nathaniel H Boyd
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Kiera Walker
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham , Birmingham, Alabama
| | - Anita B Hjelmeland
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham , Birmingham, Alabama
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Samadi AK, Bilsland A, Georgakilas AG, Amedei A, Amin A, Bishayee A, Azmi AS, Lokeshwar BL, Grue B, Panis C, Boosani CS, Poudyal D, Stafforini DM, Bhakta D, Niccolai E, Guha G, Vasantha Rupasinghe HP, Fujii H, Honoki K, Mehta K, Aquilano K, Lowe L, Hofseth LJ, Ricciardiello L, Ciriolo MR, Singh N, Whelan RL, Chaturvedi R, Ashraf SS, Shantha Kumara HMC, Nowsheen S, Mohammed SI, Keith WN, Helferich WG, Yang X. A multi-targeted approach to suppress tumor-promoting inflammation. Semin Cancer Biol 2015; 35 Suppl:S151-S184. [PMID: 25951989 PMCID: PMC4635070 DOI: 10.1016/j.semcancer.2015.03.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 12/15/2022]
Abstract
Cancers harbor significant genetic heterogeneity and patterns of relapse following many therapies are due to evolved resistance to treatment. While efforts have been made to combine targeted therapies, significant levels of toxicity have stymied efforts to effectively treat cancer with multi-drug combinations using currently approved therapeutics. We discuss the relationship between tumor-promoting inflammation and cancer as part of a larger effort to develop a broad-spectrum therapeutic approach aimed at a wide range of targets to address this heterogeneity. Specifically, macrophage migration inhibitory factor, cyclooxygenase-2, transcription factor nuclear factor-κB, tumor necrosis factor alpha, inducible nitric oxide synthase, protein kinase B, and CXC chemokines are reviewed as important antiinflammatory targets while curcumin, resveratrol, epigallocatechin gallate, genistein, lycopene, and anthocyanins are reviewed as low-cost, low toxicity means by which these targets might all be reached simultaneously. Future translational work will need to assess the resulting synergies of rationally designed antiinflammatory mixtures (employing low-toxicity constituents), and then combine this with similar approaches targeting the most important pathways across the range of cancer hallmark phenotypes.
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Affiliation(s)
| | - Alan Bilsland
- Institute of Cancer Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Alexandros G Georgakilas
- Physics Department, School of Applied Mathematics and Physical Sciences, National Technical University of Athens, Athens, Greece
| | - Amedeo Amedei
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Amr Amin
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates; Faculty of Science, Cairo University, Cairo, Egypt
| | - Anupam Bishayee
- Department of Pharmaceutical Sciences, College of Pharmacy, Larkin Health Sciences Institute, Miami, FL, United States
| | - Asfar S Azmi
- Department of Pathology, Wayne State Univeristy, Karmanos Cancer Center, Detroit, MI, USA
| | - Bal L Lokeshwar
- Department of Urology, University of Miami, Miller School of Medicine, Miami, FL, United States; Miami Veterans Administration Medical Center, Miami, FL, United States
| | - Brendan Grue
- Department of Environmental Science, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Carolina Panis
- Laboratory of Inflammatory Mediators, State University of West Paraná, UNIOESTE, Paraná, Brazil
| | - Chandra S Boosani
- Department of BioMedical Sciences, School of Medicine, Creighton University, Omaha, NE, United States
| | - Deepak Poudyal
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC, United States
| | - Diana M Stafforini
- Huntsman Cancer Institute and Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States
| | - Dipita Bhakta
- School of Chemical and Biotechnology, SASTRA University, Thanjavur, Tamil Nadu, India
| | | | - Gunjan Guha
- School of Chemical and Biotechnology, SASTRA University, Thanjavur, Tamil Nadu, India
| | - H P Vasantha Rupasinghe
- Department of Environmental Sciences, Faculty of Agriculture and Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Hiromasa Fujii
- Department of Orthopedic Surgery, Nara Medical University, Kashihara, Nara, Japan
| | - Kanya Honoki
- Department of Orthopedic Surgery, Nara Medical University, Kashihara, Nara, Japan
| | - Kapil Mehta
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Katia Aquilano
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Leroy Lowe
- Getting to Know Cancer, Truro, Nova Scotia, Canada.
| | - Lorne J Hofseth
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC, United States
| | - Luigi Ricciardiello
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | | | - Neetu Singh
- Advanced Molecular Science Research Centre (Centre for Advanced Research), King George's Medical University, Lucknow, Uttar Pradesh, India
| | - Richard L Whelan
- Department of Surgery, St. Luke's Roosevelt Hospital, New York, NY, United States
| | - Rupesh Chaturvedi
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - S Salman Ashraf
- Department of Chemistry, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - H M C Shantha Kumara
- Department of Surgery, St. Luke's Roosevelt Hospital, New York, NY, United States
| | - Somaira Nowsheen
- Medical Scientist Training Program, Mayo Graduate School, Mayo Medical School, Mayo Clinic, Rochester, MN, United States
| | - Sulma I Mohammed
- Department of Comparative Pathobiology, Purdue University Center for Cancer Research, West Lafayette, IN, United States
| | - W Nicol Keith
- Institute of Cancer Sciences, University of Glasgow, Glasgow, Scotland, UK
| | | | - Xujuan Yang
- University of Illinois at Urbana Champaign, Champaign, IL, United States
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Yuui K, Kudo R, Kasuda S, Hatake K. Ethanol attenuates vasorelaxation via inhibition of inducible nitric oxide synthase in rat artery exposed to interleukin-1β. Hum Exp Toxicol 2015; 35:938-45. [PMID: 26500219 DOI: 10.1177/0960327115611944] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Nitric oxide produced by inducible nitric oxide synthase (iNOS) regulates sepsis-induced hypotension. During septic shock, interleukin (IL)-1β is synthesized in endothelial cells and smooth muscle cells by endotoxin. Ethanol (EtOH) suppresses endotoxin-induced hypotension. The present study aimed to elucidate the effect of EtOH on gradual relaxation and iNOS expression induced by IL-1β in isolated rat superior mesenteric arteries (SMAs). Exposure to IL-1β-induced contraction in SMA rings, followed by a gradual relaxation of phenylephrine precontracted tone. Contraction was abolished by indomethacin (IM), cycloheximide (Chx), and endothelium denudation. In contrast, the gradual relaxation was abolished by NOS inhibitors, Chx, endothelium denudation, and inhibited by EtOH (50 and 100 mM). However, IM had no effect on relaxation. Western blot analysis demonstrated that iNOS expression was induced by IL-1β and was inhibited by EtOH and endothelium denudation. Furthermore, messenger RNA expression of iNOS, but not endothelial NOS, was inhibited by EtOH. These data suggest that IL-1β-induced contraction is mediated by thromboxane A2, whereas IL-1β-induced relaxation occurs via NO derived from iNOS. The endothelium plays an important role in vasorelaxation. Taken together, EtOH inhibits IL-1β-mediated vasorelaxation by suppressing endothelium iNOS expression. This study provides the first evidence of EtOH -induced inhibition of IL-1β-mediated vasorelaxation.
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Affiliation(s)
- K Yuui
- Department of Legal Medicine, Nara Medical University, Kashihara, Nara, Japan
| | - R Kudo
- Department of Legal Medicine, Nara Medical University, Kashihara, Nara, Japan
| | - S Kasuda
- Department of Legal Medicine, Nara Medical University, Kashihara, Nara, Japan
| | - K Hatake
- Department of Legal Medicine, Nara Medical University, Kashihara, Nara, Japan
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Akimov MG, Fomina-Ageeva EV, Bezuglov VV. [The optimization of the nitric oxide quantitative analysis for its determination in the cultural medium of mammalian cell culture]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2015; 41:74-81. [PMID: 26050474 DOI: 10.1134/s1068162015010021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The protocol for the quantitative analysis of nitric oxide as nitrite-ion suitable for determination of its production by a mammalian cell culture was developed. The optimal results were obtained using microvolume-adjusted Griess method after the preliminary reduction of NO3- to NO2- with non-activated cadmium. The protocol was verified on a rat glioma C6 cell culture. The developed method may be used for the nitric oxide determination in 96-well and 48-well microplates; the detection limit is 2.1 ± 0.1 μM for NO2- and 2.9 ± 0.1 μM for NO3-.
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Mandal S, Nelson VK, Mukhopadhyay S, Bandhopadhyay S, Maganti L, Ghoshal N, Sen G, Biswas T. 14-Deoxyandrographolide targets adenylate cyclase and prevents ethanol-induced liver injury through constitutive NOS dependent reduced redox signaling in rats. Food Chem Toxicol 2013; 59:236-48. [PMID: 23764359 DOI: 10.1016/j.fct.2013.05.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/25/2013] [Accepted: 05/29/2013] [Indexed: 02/07/2023]
Abstract
Chronic alcoholism is one of the most common causes of liver diseases worldwide. Nitric oxide (NO) has been proposed to have potential for clinical application against chronic hepatocellular injuries. However, mechanisms underlying hepatoprotective functions of NO in ethanol-induced apoptosis are largely unknown. Sprauge-Dawley rats were exposed to ethanol for 8 weeks. Half of the ethanol-fed animals received 14-deoxyandrographolide (14-DAG) treatment for the last 4 weeks of study. Preventive effect of 14-DAG against ethanol-induced hepatotoxicity involved constitutive nitric oxide synthase (cNOS) activation followed by up-regulation of γ-glutamylcysteine synthetase activity and reduced oxidative stress. Enhanced interaction of cNOS with caveolin-1 caused down-regulation of enzyme activity and led to depletion of NO in the hepatocytes of ethanol-fed animals. 14-DAG acted as activator of adenylate cyclase and modulated cyclic AMP (cAMP) mediated expression of caveolin-1 and calmodulin. This eventually favored activation of cNOS through inhibition of cNOS-caveolin-1 interaction. Our results suggest that, protective effect of 14-DAG against ethanol-induced hepatic injury is based on its ability to reduce oxidative stress through cNOS dependent improvement of redox status. 14-DAG mediated activation of adenylate cyclase-cAMP signaling leading to up-regulation of cNOS may provide a promising approach in the prevention of liver diseases during chronic alcoholism.
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Affiliation(s)
- Samir Mandal
- Cell Biology & Physiology Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
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Davis RL, Sanchez AC, Lindley DJ, Williams SC, Syapin PJ. Effects of mechanistically distinct NF-kappaB inhibitors on glial inducible nitric-oxide synthase expression. Nitric Oxide 2005; 12:200-9. [PMID: 15890551 DOI: 10.1016/j.niox.2005.04.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2004] [Revised: 02/23/2005] [Accepted: 04/05/2005] [Indexed: 11/19/2022]
Abstract
Nuclear factor (NF)-kappaB is an important regulator of inflammatory gene expression. Transcriptional regulation of Nos2, the inducible nitric-oxide synthase (iNOS) gene, is complex and not fully understood, but appears to be regulated in part by NF-kappaB. To further understand the role of NF-kappaB in Nos2 expression, we compared three functionally distinct NF-kappaB inhibitors on NF-kappaB transactivation and iNOS induction by rat C6 glial cells. Cytokine-induced activation of a consensus NF-kappaB-reporter gene was concentration-dependently inhibited by BAY 11-7082, MG-132, and helenalin. The rank order of potency was MG-132>helenalin>BAY 11-7082, with low concentrations of helenalin stimulating reporter gene activity. Cytokine-stimulated iNOS expression, measured by nitrite accumulation and in vitro l-citrulline production, was similarly reduced by exposing C6 cells to the NF-kappaB inhibitors. Surprisingly, activation of Nos2-reporter gene constructs containing the proximal 188 bp (containing one kappaB site) or proximal 94 bp (no kappaB site) of the rat promoter also was inhibited with the same rank order of potency. Interestingly, low concentrations of helenalin increased activity of both promoter constructs, while BAY 11-7082 poorly inhibited the 94-bp activity. This is the first report describing BAY 11-7082 and helenalin effects on iNOS expression in astroglia. Given the reported mechanism of actions for these inhibitors, cytokine-induced glial iNOS expression appears more sensitive to disruption of proteasome degradation and p65 function than modulation of IkappaB phosphorylation. These findings may foster the design of therapeutic agents aimed at NF-kappaB-associated pathways involved in neuroinflammation, especially iNOS expression.
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Affiliation(s)
- Randall L Davis
- Alcohol and Brain Research Laboratory, Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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7
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Davis RL, Syapin PJ. Interactions of alcohol and nitric-oxide synthase in the brain. ACTA ACUST UNITED AC 2005; 49:494-504. [PMID: 16269316 DOI: 10.1016/j.brainresrev.2005.01.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Revised: 12/08/2004] [Accepted: 01/24/2005] [Indexed: 11/30/2022]
Abstract
Nitric oxide (NO) is an important molecule associated with both physiological and pathological brain events. Three separate genes encode for nitric-oxide synthase (NOS), the rate-limiting enzyme in NO production, all of which are expressed within brain tissue. Effects of ethanol on NO production may be important to ethanol modification of brain function. Existing data indicate that alcohol exposure alters NOS expression and activity in the brain. Modulation of NOS is suggested to be involved in alcohol-induced behavioral modifications. Furthermore, alcohol-induced changes in NOS may alter immunocompetence, response to injury in the central nervous system, and may be involved in ethanol-mediated neurodegeneration and neurotoxicity. The extent and direction of change in NOS expression and activity depends on cell type and length of exposure. The mechanisms underlying these effects are only partially understood. Herein, the current understanding of the interactions of ethanol and NOS in the brain are discussed.
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Affiliation(s)
- Randall L Davis
- Department of Pharmacology/Physiology, Neuroinflammation Research Laboratory, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, USA.
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9
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Boyadjieva NI, Chen CP, Sarkar DK. Role of nitric oxide in alcohol alteration of beta-endorphin release from hypothalamic cells in primary cultures. Alcohol Clin Exp Res 2004; 27:1813-8. [PMID: 14634498 DOI: 10.1097/01.alc.0000093740.63754.0c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Nitric oxide (NO) mediates many pharmacological actions of ethanol. NO's role in regulating ethanol action on hypothalamic beta-endorphin (beta-EP) neurons is not established. METHODS In this study, we determined the role of NO in ethanol regulation of beta-EP release from primary cultures of rat fetal mediobasal hypothalamic cells. Real-time polymerase chain reaction was used for messenger RNA (mRNA) detection; radioimmunoassay was used for hormone measurements. RESULTS Acute ethanol treatment for 3 hr increased the release of beta-EP but reduced nitrite levels in the media of hypothalamic cells in primary cultures. In contrast, ethanol exposure for 48 hr reduced the release of beta-EP but increased the release of nitrite from these cells. Alcohol treatments altered the expression of neuronal NO synthase mRNA, but not inducible NO synthase mRNA, in a pattern similar to that of nitrite levels. Alcohol treatments blocked sodium nitroprusside-induced increases in the level of cellular cyclic guanidine monophosphate. The nonspecific NO blocker NG-nitro-l-arginine-methyl-esther, but not the inactive isomer N-nitro-d-arginine-methyl-esther (d-NAME), inhibited ethanol inhibitory actions on beta-EP release. CONCLUSIONS These results suggest that the cyclic guanidine monophosphate/NO pathway is involved in ethanol alteration of hypothalamic beta-EP release.
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Affiliation(s)
- Nadka I Boyadjieva
- Center for Alcohol Studies and Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick 08901-8525, USA
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Sanchez AC, Davis RL, Syapin PJ. Identification of cis-regulatory regions necessary for robust Nos2 promoter activity in glial cells: indirect role for NF-kappaB. J Neurochem 2003; 86:1379-90. [PMID: 12950447 DOI: 10.1046/j.1471-4159.2003.01943.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previous reports suggest the nitric-oxide synthase 2 (Nos2) promoter contains negative and positive cis-regulatory regions. This study identified such regions using rat C6 glial cells. Activity of the serially deleted rat Nos2 promoter fused to a luciferase reporter gene was found to vary with construct size independent of stimuli, decreasing markedly from 160 to 130 bp then increasing significantly from 110 to 94 bp. In contrast, time to peak activity was stimulus-dependent but size-independent; 4-8 h for a cytokine mixture or lipopolysaccharide + interferon-gamma, and 8-16 h for lipopolysaccharide + phorbol 12-myristate 13-acetate. Peak activity with heterologous promoters also varied; 4 h for 3.7 kb of the human Nos2A promoter, and 36 h for 1.8 kb of the murine promoter. Electrophoretic mobility shift assays and in vivo DNA footprinting data confirmed nuclear protein binding to promoter regions suspected of containing important regulatory sites based on reporter gene data. A binding site for NF-kappaB was not required for Nos2 promoter activity. These findings provide significant new information on the relative importance of different regions of the rat Nos2 promoter for transcriptional activation and nitric oxide production by glial cells and support the existence of cell- and species-specific mechanisms for transcriptional regulation of Nos2 activation.
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Affiliation(s)
- Alma C Sanchez
- Alcohol and Brain Research Laboratory, Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, Texas, USA
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Usta C, Sadan G. The effect of chronic ethanol administration on nitric oxide-mediated responses in rat isolated trachea preparation. ACTA ACUST UNITED AC 2003; 23:73-8. [PMID: 14565541 DOI: 10.1046/j.1474-8673.2003.00281.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. In the present study, we investigated the effect of chronic ethanol administration on nitric oxide (NO)-mediated responses in rat isolated trachea preparation. 2. Ethanol was given to rats in a modified liquid diet for 21 days. Isolated tracheal rings were then used to obtain responses to electrical field stimulation (EFS) after precontraction with 100 microM histamine. The parameters of field stimulation were as follows: supramaximal voltage of 50 V, 0.5 ms duration, 10-s train; 0.5, 1, 3, 5, 10, 20, 30 and 50 Hz at 2-min intervals. The effects of L-and D-arginine (10(-6) M) on the responses to field stimulation (10-20 Hz) were studied. In other experiments, we tested the effects of N(omega)-nitro-L-arginine methyl ester (L-NAME, 10(-6)-10(-5) M) and SIN-1 (10(-6)-10(-5) M) on the responses to field stimulation. 3. Electrical field stimulation induced relaxation responses in the tracheal rings precontracted with histamine from control- and ethanol-treated rats. The relaxation responses induced by EFS were significantly reduced in the tracheal rings precontracted with histamine from ethanol dependent group. The responses induced by EFS in both groups were completely abolished by tetrodotoxin (1 microM), but unaffected by hexamethonium (1 microM). Incubation with D-arginine did not cause statistically significant increases in relaxation responses to EFS in both groups. L-Arginine (10(-6) M) caused statistically significant increases in relaxation responses to EFS in control rats, but not in ethanol dependent rats. Incubation with L-NAME (10(-6)-10(-5) M) caused statistically significant inhibition of the relaxation responses to EFS in both groups. SIN-1 (10(-6)-10(-5) M) induced significantly increase in relaxation responses to EFS in both groups. 4. Our results suggest that the possible mechanism responsible for inhibition of tracheal inhibitory responses to EFS in ethanol-dependent rats may be a reduction in production of NO and in the uptake of L-arginine.
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Affiliation(s)
- C Usta
- Department of Pharmacology, Akdeniz University, Faculty of Medicine, 07070 Arapsuyu, Antalya, Turkey
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An essential component in steroid synthesis, the steroidogenic acute regulatory protein, is expressed in discrete regions of the brain. J Neurosci 2003. [PMID: 12486153 DOI: 10.1523/jneurosci.22-24-10613.2002] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Recent data implicate locally produced steroids, termed neurosteroids, as regulators of neuronal function. Adrenal and gonadal steroidogenesis is controlled by changes in the steroidogenic acute regulatory protein (StAR); however, little is known about the regulation of neurosteroid production. We now demonstrate unequivocally that StAR mRNA and protein are expressed within glia and neurons in discrete regions of the mouse brain, and that glial StAR expression is inducible. Consistent with a role in de novo neurosteroidogenesis, StAR colocalizes with the cholesterol side-chain cleavage enzyme P450(scc) in both mouse and human brains. These data support a role for StAR in the production of neurosteroids and identify potential sites of active de novo steroid synthesis in the brain.
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Ren L, Syapin PJ. Dual mechanisms for ethanol-induced inhibition of monocyte chemotactic protein-3 mRNA expression in activated glial cells. J Pharmacol Exp Ther 2002; 303:265-72. [PMID: 12235260 DOI: 10.1124/jpet.102.035253] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The differential display of mRNA technique was used to screen the expressed genes in control and 50 mM chronic ethanol-treated rat C6 glial cells, with and without activation by lipopolysaccharide (LPS) combined with phorbol 12-myristate 13-acetate (PMA). One differentially expressed transcript was identified as that corresponding to the chemokine monocyte chemotactic protein (MCP)-3. MCP-3 is a broadly active chemokine that functions in chemoattraction and activation of monocytes, T lymphocytes, eosinophils, basophils, natural killer cells, and dendritic cells. Steady-state MCP-3 mRNA levels were elevated 6-fold after 24-h stimulation of control cells but less than 3-fold after stimulation of 9-day chronic ethanol-exposed cells. One- and 5-day exposures to 50 mM ethanol were not effective at reducing steady-state MCP-3 mRNA levels in stimulated cells, whereas 1-day exposure to >150 mM ethanol was effective. Stimulation with tumor necrosis factor-alpha elevated MCP-3 mRNA in C6 glial cells to a lesser extent than with LPS plus PMA, but the effects of ethanol were consistent. To gain insight into possible mechanisms for ethanol-induced reductions in steady-state MCP-3 mRNA, additional studies examined nuclear MCP-3 RNA levels and MCP-3 mRNA degradation. MCP-3 RNA content was greatly reduced in isolated nuclei from acute and chronic ethanol-exposed cells, suggesting transcriptional inhibition. On the other hand, acute ethanol exposure enhanced degradation of preexisting MCP-3 mRNA, indicating message destabilization. Thus, the results are consistent with a dual mechanism for ethanol-induced reductions in steady-state MCP-3 mRNA levels.
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Affiliation(s)
- Liqiang Ren
- Department of Pharmacology, Alcohol and Brain Research Laboratory, Texas Tech University Health Sciences Center, Lubbock 79430, USA
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Davis RL, Dertien J, Syapin PJ. Ethanol-Induced Modulation of Inducible Nitric-Oxide Synthase Activity in Human A172 Astrocytoma Cells. Alcohol Clin Exp Res 2002. [DOI: 10.1111/j.1530-0277.2002.tb02685.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sun H, Patel KP, Mayhan WG. Tetrahydrobiopterin, a cofactor for NOS, improves endothelial dysfunction during chronic alcohol consumption. Am J Physiol Heart Circ Physiol 2001; 281:H1863-9. [PMID: 11668045 DOI: 10.1152/ajpheart.2001.281.5.h1863] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We sought to investigate mechanisms that may account for impaired nitric oxide synthase (NOS)-dependent dilatation of cerebral arterioles during alcohol consumption. Our goals were to examine 1) the effect of exogenous application of a cofactor for NOS, i.e., tetrahydrobiopterin (BH4) on the reactivity of pial arterioles during alcohol consumption; and 2) endothelial NOS (eNOS) protein in nonalcohol-fed and alcohol-fed rats. Sprague-Dawley rats were fed liquid diets with or without alcohol for 2-3 mo. We measured in vivo diameter of pial arterioles in response to NOS-dependent agonists (ACh and ADP) and a NOS-independent agonist (nitroglycerin) before and during application of BH4. Blood vessels were then harvested for Western blot analysis of eNOS protein. In nonalcohol-fed rats, ACh and ADP produced vasodilatation, which was impaired in alcohol-fed rats. Vasodilatation to nitroglycerin was similar in both groups of rats. Application of BH4 did not alter vasodilatation in nonalcohol-fed rats but improved impaired vasodilatation in alcohol-fed rats. Also, eNOS protein in cerebral cortex microvessels, the basilar artery, and aorta was not different between nonalcohol-fed and alcohol-fed rats. Thus impaired NOS-dependent vasodilatation during alcohol consumption does not appear to be related to an alteration in eNOS protein but may be related to a deficiency and/or alteration in the utilization of BH4.
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Affiliation(s)
- H Sun
- Department of Physiology and Biophysics, University of Nebraska Medical Center, Omaha, Nebraska 68198-4575, USA
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Shi J, Larson DF, Yang B, Hunter K, Gorman M, Montes S, Beischel J, Watson RR. Differential effects of acute ethanol treatment on cardiac contractile function in young adult and senescent mice. Alcohol 2001; 24:197-204. [PMID: 11557305 DOI: 10.1016/s0741-8329(01)00154-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
It is understood that marked biochemical, molecular, and performance alterations occur in cardiovascular tissues related to aging. It is logical, therefore, that differences in the cardiovascular response to ethanol consumption, when comparing younger with older individuals, may exist. We compared the left ventricular function of 6- and 15-month-old (senescent) mice and 16-month-old (senescent) inducible nitric oxide synthase knockout mice (n=7 each) before and subsequent to acute treatment with 60% ethanol (2 g/kg, i.p.). A Millar 1.4 Fr conductance/micromanometer catheter was placed into the left ventricle of the mice for acquisition of pressure-volume loops. Heart contractile functions were significantly decreased in the senescent group, compared with findings in the younger mice. Subsequent to ethanol treatment, the younger mice showed a significant reduction in cardiac function, with a 28% decrease in cardiac index, a 29% decrease in end-systolic elastance, and a 16% decrease in preload recruitable stroke work (P<.01). Conversely, the senescent mice showed significantly increased contractile function, with a 40% increase in end-systolic elastance (P<.01) and a 19% increase in preload recruitable stroke work (P<.05). The myocardial cyclic guanosine monophosphate levels were significantly higher in the older group (P<.002), and subsequent to ethanol treatment, they were decreased by 68.5% (P<.001). Northern blot analysis demonstrated inducible nitric oxide synthase message only in senescent myocardial tissues. Moreover, the cardiac function of senescent inducible nitric oxide synthase knockout mice was comparable with that of young mice, and after ethanol treatment, cardiac function decreased significantly, just as that for young mice did, with a 26% decrease in cardiac index (P<.05) and a 23% decrease in preload recruitable stroke work (P<.01). It was concluded that the differential cardiovascular function and response to acute ethanol
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Affiliation(s)
- J Shi
- Arizona Prevention Center, College of Medicine, The University of Arizona, Tucson, AZ 85724, USA
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17
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Shih CL, Chi SI, Chiu TH, Sun GY, Lin TN. Ethanol Effects on Nitric Oxide Production in Cerebral Pial Cultures. Alcohol Clin Exp Res 2001. [DOI: 10.1111/j.1530-0277.2001.tb02258.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Abstract
There is strong evidence showing that chronic and excessive ethanol consumption may enhance oxidative damage to neurons and result in cell death. Although not yet well understood, ethanol may enhance ROS production in brain through a number of pathways including increased generation of hydroxyethyl radicals, induction of CYP2E1, alteration of the cytokine signaling pathways for induction of iNOS and sPLA(2), and production of prostanoids through the PLA(2)/COX pathways. Since many neurodegenerative diseases are also associated with oxidative and inflammatory mechanisms in the brain, it would be important to find out whether chronic and excessive ethanol consumption may exacerbate the progression of these diseases. There is evidence that the polyphenolic antioxidants, especially those extracted from grape skin and seed, may protect the brain from neuronal damage due to chronic ethanol administration. Among the polyphenols from grapes, resveratrol seems to have unique antioxidant properties. The possible use of this compound as a therapeutic agent to ameliorate neurodegenerative processes should be further explored.
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Affiliation(s)
- A Y Sun
- Department of Pharmacology, University of Missouri, Columbia, MO 65212, USA.
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19
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Wang JH, Sun GY. Ethanol inhibits cytokine-induced iNOS and sPLA2 in immortalized astrocytes: evidence for posttranscriptional site of ethanol action. J Biomed Sci 2001; 8:126-33. [PMID: 11173986 DOI: 10.1007/bf02255981] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Chronic and excessive ethanol consumption is known to alter neuron and glial cell functions in the central nervous system (CNS). Astrocytes comprise the major cell type in the brain. These immune active cells are capable of responding to proinflammatory cytokines and endotoxins, which stimulate transcriptional pathways leading to induction of genes, including the inducible nitric oxide synthase (iNOS) and secretory phospholipase A2 (sPLA2). In this study, we investigate the effects of ethanol on cytokine-induced iNOS and sPLA2 in immortalized astrocytes (DITNC). When DITNC cells were exposed to ethanol (0-200 mM) for 4 h prior to subsequent stimulation with cytokines for 16 h, NO production decreased with increasing ethanol concentrations starting from 50 mM. At ethanol concentrations higher than 100 mM, ethanol also inhibited cytokine-induced sPLA2 release into the culture medium. The inhibitory effect of ethanol on NO production corresponds well with the decrease in iNOS protein and NOS enzyme activity, but not with iNOS and sPLA2 mRNA nor binding of NF-kappaB to DNA. The inhibition of cytokine-induced NO production by ethanol was also dependent on the time of ethanol exposure to the cells, but addition of acetaldehyde up to 200 microM did not elicit any changes. Taken together, these results provide evidence for a posttranscriptional mode of ethanol action on the cytokine induction pathway for NO production in astrocytes.
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Affiliation(s)
- J H Wang
- Department of Nutritional Sciences, University of Missouri, Columbia, MO 65212, USA
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20
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Ren LQ, Garrett DK, Syapin M, Syapin PJ. Differential fibronectin expression in activated C6 glial cells treated with ethanol. Mol Pharmacol 2000; 58:1303-9. [PMID: 11093767 DOI: 10.1124/mol.58.6.1303] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The central nervous system is particularly susceptible to alcohol effects and toxicity. Glial cells constitute the most common cell type in the brain and play critical roles in normal brain function and during infection and injury. Astrocytes in particular seem to be important targets for alcohol neurotoxicity during both development and in adulthood. To gain more insight into alcohol-mediated effects on astrocytes at the molecular level, gene expression in rat C6 glial cells was studied in the presence or absence of ethanol. The differential display of mRNA technique was used to screen the expressed genes in ethanol-treated rat C6 cells before and after treatment with lipopolysaccharide (LPS) combined with phorbol-12-myristate-13-acetate (PMA), conditions that mimic an infectious inflammatory state and cause immunologic activation. The present data show that fibronectin appeared as a major gene whose expression is increased in C6 cells by LPS plus PMA stimulation and decreased by chronic ethanol exposure, both in mRNA and protein levels. Fibronectin is a dimeric glycoprotein found in the extracellular matrix of most tissues, in the blood, and on cell surfaces and is involved in many cellular processes. These results show that chronic exposure to ethanol is associated with changes in astrocyte properties during immunologic activation that reduce fibronectin expression. The discovery of astrocyte fibronectin expression as a potential regulated target for chronic alcohol abuse may be useful in understanding, preventing, and treating some brain disorders associated with alcohol abuse and alcoholism.
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Affiliation(s)
- L Q Ren
- Alcohol and Brain Research Laboratory, Department of Pharmacology, Texas Tech University Health Sciences Center, Lubbock, Texas 79430-0001, USA
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21
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Greenberg SS, Xie J, Ouyang J, Zhao X. Ethanol metabolism is not required for inhibition of LPS-stimulated transcription of inducible nitric oxide synthase. Alcohol 1999; 17:203-13. [PMID: 10231168 DOI: 10.1016/s0741-8329(98)00048-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We examined the effect of inhibition of ethanol metabolism on ethanol-mediated suppression of Escherichia coli endotoxin (LPS-induced upregulation of transcription and release of inducible nitric oxide synthase (iNOS) and tumor necrosis factor alpha (TNFalpha) from rat alveolar macrophages (AM) in vivo. Ethanol (3.45 and 5.5 g/kg/IP) and t-butanol (3.7 g/kg, IP), given 30 min before intratracheal administration of LPS (1.0 mg/kg), inhibited the upregulation of iNOS mRNA and protein, determined by competitor equalized RT-PCR and Western immunoblot, respectively, but not TNFalpha mRNA in AM obtained 2 h after LPS administration by bronchoalveolar lavage (BAL). However, ethanol and t-butanol inhibited LPS-stimulated nitrate and nitrite (RNI) and TNFalpha protein in BAL fluid. Pretreatment of rats with 4-methylpyrazole (100 mg/kg, IP) 2 h before, or disulfiram 30 min before, administration of ethanol (3.45 g/kg, IP) failed to attenuate the inhibitory effect on iNOS mRNA or protein. t-Butyl hydroperoxide (100 mg/kg, IP) given to rats 30 min before administration of LPS enhanced LPS-mediated upregulation of iNOS mRNA and TNFalpha protein in AM and BAL fluid. The inhibitory effect of ethanol on iNOS mRNA was not mediated by an interaction with elevated levels of circulating corticosterone because pretreatment of rats with RU-38486 (100 mg/kg, IM), which inhibited prednisolone (50 mg/kg, IM), induced suppression of LPS-stimulated iNOS mRNA, and failed to attenuate ethanol-mediated inhibition of LPS-stimulated iNOS mRNA in AM. We conclude that metabolism of ethanol to acetaldehyde via alcohol dehydrogenase is not required for ethanol-mediated suppression of LPS-induced iNOS transcription and TNFalpha synthesis/release in AM. Moreover, an interaction of ethanol or acetaldehyde with circulating corticosterone is not involved in ethanol-mediated attenuation of LPS-stimulated iNOS mRNA or protein or TNFalpha protein in the lung. Speculatively, because oxidation of t-butanol to t-butylhydroperoxide results in activation, rather than inhibition, of iNOS and TNF-alpha, the reported ethanol-mediated enhancement of iNOS mRNA may result from the action of the hydroxyethyl radical.
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Affiliation(s)
- S S Greenberg
- Department of Medicine, The Alcohol Research Center, Louisiana State University Medical Center, New Orleans 70112, USA.
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22
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Syapin PJ, Rendon A, Huron DR, Militante JD. Effects of short chain alkanols on the inducible nitric oxide synthase in a glial cell line. Br J Pharmacol 1999; 126:1253-61. [PMID: 10205016 PMCID: PMC1565888 DOI: 10.1038/sj.bjp.0702417] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. Ethanol inhibits inducible nitric oxide synthase (iNOS) expression in C6 glioma cells by an unknown mechanism. Because relatively high concentrations are needed for inhibition in drug-naive cells (IC50 approximately = to 150 mM), suppression due to cytotoxicity is one possible mechanism that has not been ruled out. Therefore, the present study examined the effects of ethanol and other alkanols on C6 glioma cell viability and iNOS activity to better understand the mechanism for inhibition. 2. iNOS expression was induced in cell culture with lipopolysaccharide and phorbol ester treatment. Nitrite accumulation in culture medium, the in vitro conversion of [3H]-L-arginine to [3H]-L-citrulline, and immunoblotting were used to quantify iNOS induction and activity. Trypan blue exclusion, extracellular release of lactate dehydrogenase, and quantity of total cell protein were used as measures of viability. 3. Short chain alkanols, methanol through 1-heptanol, concentration-dependently inhibited nitrite accumulation. Longer chain alkanols, 1-octanol and 1-decanol, did not except at cytotoxic concentrations. Experiments indicated short chain alkanol inhibition was not due to direct actions on iNOS catalytic activity, but that it transpires during iNOS induction. Immunoblots showed reduced iNOS protein levels. 4. Correlation analysis ruled out iNOS inhibition as being due to decreased cell number, total cell protein, or cell viability. In contrast, there was significant correlation with physical measures of lipophilicity. 5. In conclusion, inhibition of iNOS expression by ethanol and other short chain alkanols is not due to cytotoxicity. Instead, the strong correlation with lipophilicity suggests the inhibition derives from an interaction with unknown hydrophobic cellular sites.
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Affiliation(s)
- P J Syapin
- Department of Pharmacology, School of Medicine, Texas Tech University Health Sciences Center, Lubbock 79430, USA.
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23
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Wang JY, Wang JY, Wang JY, Shum AY, Hwang CP. Ethanol modulates induction of nitric oxide synthase in glial cells by endotoxin. Life Sci 1998; 63:1571-83. [PMID: 9808068 DOI: 10.1016/s0024-3205(98)00424-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although ethanol has long been recognized as an immunosuppressant, the effects of ethanol on immune functions in the central nervous system (CNS) have not been well characterized. Glial cells function as immune effector cells within the CNS. Nitric oxide (NO), generated by inducible NO synthase (iNOS) of activated glial cells, appears to participate in the immune defense and the pathogenesis of brain injury and several neurologic diseases. The goal of the present study was to examine the effects of ethanol on NO production and mRNA expression of iNOS following its induction by bacterial endotoxin lipopolysaccharide (LPS) in cultured glial cells. After incubation of mixed glia with LPS for 24 hr, the levels of nitrite in the culture medium were assayed by Griess reaction. We found that LPS (10-500 ng/ml) induced a concentration-dependent increase in the production of NO which was abolished by the selective iNOS inhibitor aminoguanidine. While ethanol treatment (25 to 400 mM, 24 hr exposure) had no direct effect on basal NO production, it significantly suppressed the LPS-induced increase of nitrite levels in a concentration-dependent manner. Using a semiquantitative reverse transcriptase polymerase chain reaction, we found that while ethanol by itself was unable to induce iNOS mRNA, it nevertheless suppressed LPS-induced iNOS mRNA expression. Our results that ethanol had no direct effect on NO production but inhibited LPS-induced NO, indicated an immunomodulatory role by ethanol. These findings suggest that ethanol may ameliorate the consequences of overwhelming NO generation through iNOS induction in glial cells following infection, inflammation or CNS injuries.
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Affiliation(s)
- J Y Wang
- Department of Physiology, National Defense Medical Center, Taipei, Taiwan, ROC.
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24
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Greenberg SS, Jie O, Zhao X, Wang JF. Role of PKC and tyrosine kinase in ethanol-mediated inhibition of LPS-inducible nitric oxide synthase. Alcohol 1998; 16:167-75. [PMID: 9665319 DOI: 10.1016/s0741-8329(97)00187-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ethanol increases human and animal susceptibility to opportunistic lung infections in part by suppression of endotoxin (LPS) and bacteria-mediated upregulation of inducible nitric oxide synthase (iNOS) in alveolar macrophages (AM). LPS and cytokine-induced NOS mRNA are dependent on NF-kappaB/Rel (NFkappaB) and Activator Protein-1 (AP-1), which are regulated in turn by protein kinase C and tyrosine kinase-dependent phosphorylation. ETOH does not directly inhibit NFkappaB or AP-1, in vivo, but rather inhibits LPS-induced activation of the MEKK/MAP kinase system and inhibition of inhibitory protein IkappaBalpha required for formation of AP-1 and NFkappaB, respectively. in AM. Both transcription factors are involved iNOS mRNA transcription. LPS-induced upregulation of MEKK/MAP tyrosine kinase upregulates NADPH oxidase activity and oxygen free radical formation required for activation of NFkappaB and AP-1 and phosphorylation of IkappaBalpha. LPS downregulates endogenous calcium-sensitive PKC isozymes (PKCdelta), which repress iNOS mRNA expression. ETOH inhibits LPS-induced upregulation of iNOS mRNA by preventing its ability to decrease PKCdelta and upregulate tyrosine kinase-mediated phosphorylation. This effect of ETOH is prevented by inhibitors of PKC and tyrosine kinase. The data support the hypothesis that ETOH inhibits LPS-induced upregulation of iNOS mRNA by interfering with the phosphorylation processes involved in activation of the nuclear transcription factors NFkappaB and AP-1.
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Affiliation(s)
- S S Greenberg
- Alcohol Research Center, Department of Medicine, Louisiana State University Medical Center, New Orleans 70112, USA
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25
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Abstract
The L-arginine-nitric oxide pathway is important to both physiological and pathologic brain events. Brain tissue contains cells able to express all known isoforms of nitric oxide synthase, the rate-limiting enzyme in nitric oxide (NO) production and release. Effects of ethanol on NO production may be important to ethanol modification of brain function. Recent studies support this idea and demonstrate diverse interactions. For example, acute ethanol treatment decreases NMDA- and cytokine-stimulated NO synthesis by cortical neurons and glia, respectively, but enhances cytokine-stimulated NO synthesis in blood-brain barrier endothelial cells and does not affect norepinephrine-stimulated NO synthesis in medial basal hypothalamus. Furthermore, chronic ethanol enhances NMDA-stimulated NO synthesis in cortical neurons, but more potently decreases cytokine-induced NO synthesis in glial cells. The mechanisms underlying these effects are partially understood and include changes in NOS-2 gene expression. These observations illustrate that ethanol selectively affects NO production by brain cells, which may relate to reported behavioral interactions, but the extend and direction of change depends on cell type and length of exposure.
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Affiliation(s)
- P J Syapin
- Department of Pharmacology, Texas Tech University Health Sciences Center, Lubbock 79430-0001, USA
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26
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Abstract
Nitric oxide is an important messenger in the central nervous system and several types of evidence suggest that it mediates various alcohol effects. Treatment with a nitric oxide synthase inhibitor enhances the acute central depressant or anesthetic effect of alcohol and decreases some stimulatory effects of alcohol withdrawal after chronic alcohol treatment. Conversely, treatment with a nitric oxide donor inhibits the anesthetic effect of alcohol, blocks the effect of the nitric oxide synthase inhibitor on alcohol anesthesia, and enhances the severity of some alcohol withdrawal signs. These results indicate that changes in nitric oxide synthesis mediate some aspects of alcohol intoxication and withdrawal and that nitric oxide systems represent an important therapeutic target for the development of agents to treat alcoholism and alcohol intoxication.
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Affiliation(s)
- M L Adams
- Washington University School of Medicine, St. Louis, MO 63110-1093, USA.
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27
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Colton CA, Snell-Callanan J, Chernyshev ON. Ethanol Induced Changes in Superoxide Anion and Nitric Oxide in Cultured Microglia. Alcohol Clin Exp Res 1998. [DOI: 10.1111/j.1530-0277.1998.tb04315.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Chu AJ, Moore J, Sime R, Yu WH, Li Z. Antagonism by ethanol of endotoxin-induced tissue factor activation in relation to the depressed endotoxin binding to monocyte-like U937 cells. Cell Biochem Funct 1997; 15:271-81. [PMID: 9415974 DOI: 10.1002/(sici)1099-0844(199712)15:4<271::aid-cbf751>3.0.co;2-l] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Our previous study has reported that ethanol (ETOH) partially inhibited the endotoxin (LPS)-induced tissue factor (TF)-activation in monocytes including blood peripheral monocytes as well as cultured leukemic U937 and THP-1 cells. The present study shows a strong correlation (r = 0.92; p < 0.01) between TF-activation and depression in LPS binding blocked by ETOH in U937 cells. The antagonism by ETOH of LPS binding was not due to a direct extracellular blockade, since ETOH did not affect the affinity of fluorescein isothiocyanate (FITC)-LPS or -anti CD14 mAb on U937 cells. After U937 cells were treated with 2 per cent (v/v) ETOH for 3 h, LPS binding was however drastically inhibited as shown by immunostaining with FITC-LPS which was viewed on a confocal laser scanning microscope. The results imply that cellular events of the ETOH effect mediate this inhibition of LPS binding. Anti-CD14 mAb (UCHM-1) inhibited LPS binding in a dose-dependent fashion, revealing a competitive specific binding to the LPS receptor. The results suggest that CD14 plays an important role in the recognition of LPS. FITC-UCHM-1 binding was significantly reduced in the cells pretreated with 2 per cent (v/v) ETOH for 3 h, indicating that ETOH modulates the ability to express CD14. CD14 expression was upregulated by priming with LPS which was offset by ETOH. Acetaldehyde, a possible metabolite of ETOH, was tested with no effect on CD14 expression. Taken together, our results show that ETOH downregulates the recognition of LPS, and suggest that the inhibitory action is likely to be mediated by the depression in CD14 expression which was also accompanied by a significantly altered membrane fluidity. Thus, the antagonism by ETOH of the binding of LPS results in a depression in the LPS-induced TF-activation.
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Affiliation(s)
- A J Chu
- Department of Cell Biology and Anatomy, University of Miami Medical School, FL 33130, USA
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29
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Miller KJ, Mariano CL, Cruz WR. Serotonin 5HT2A receptor activation inhibits inducible nitric oxide synthase activity in C6 glioma cells. Life Sci 1997; 61:1819-27. [PMID: 9365229 DOI: 10.1016/s0024-3205(97)00806-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
C6-glioma cells endogenously express both 5HT2A receptors and inducible nitric oxide synthase (iNOS). iNOS can be induced by transcriptional activation to produce nitric oxide (NO) in response to a challenge with lipopolysaccharide (LPS). Experiments were conducted to determine whether 5HT2A receptor activation could modify the production of NO in response to LPS. Incubation of 10 microg/ml LPS with C6-glioma cells for a period of 24 hours resulted in a 2.6 fold increase in nitrite levels, as a measure of NO levels, over vehicle treated controls. Co-incubation with the selective 5HT2A receptor partial agonist (+/-)-2,5-dimethoxy-4-iodoamphetamine (DOI) produced a dose-dependent inhibition of the LPS-induced nitrite levels of 22% with an IC50 of 16 nM. The full agonists serotonin (5HT) and alpha-methyl-5HT produced an inhibition of approximately 30% at a concentration of 1 microM. The inhibitory effect of 1 microM DOI was blocked by the 5HT2A receptor antagonists spiperone and ritanserin (10 nM). Inhibition of protein kinase C (PKC) using 100 nM chelerythrine prevented the DOI-mediated decrease in LPS-induced nitrite levels. Addition of DOI to the cells after 1 hr following the LPS addition did not produce a decrease in nitrite levels indicating iNOS was not modified post-translationally. The data demonstrate that iNOS activity can be modulated by serotonin 5HT2A receptor activation, most likely at the initiation of the induction process, via PKC. We therefore suggest that there may be a link between the serotonergic system and NO-mediated immune responses in the brain.
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Affiliation(s)
- K J Miller
- Department of Pharmaceutical Sciences, College of Pharmacy, Nova Southeastern University, Davie, FL 33325, USA.
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30
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Zhao X, Jie O, Li H, Xie J, Giles TD, Greenberg SS. Ethanol Inhibits Inducible Nitric Oxide Synthese Transcription and Post-Transcriptional Processes in Vivo. Alcohol Clin Exp Res 1997. [DOI: 10.1111/j.1530-0277.1997.tb04445.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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31
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Naassila M, Roux F, Beaugé F, Daoust M. Ethanol potentiates lipopolysaccharide- or interleukin-1 beta-induced nitric oxide generation in RBE4 cells. Eur J Pharmacol 1996; 313:273-7. [PMID: 8911924 DOI: 10.1016/0014-2999(96)00643-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Our present study investigated the effects of ethanol treatment on inducible nitric oxide (NO) synthase pathway from lipopolysaccharide- or interleukin-1 beta-treated cultured rat blood-brain barrier cell line (rat brain endothelial 4 cells: RBE4 cells). Cells were lipopolysaccharide- or interleukin-1 beta-treated with or without ethanol (50, 100 or 200 mM) for 16 or 24 h. Inducible NO synthase activity and mRNA expression were measured using Griess reaction and reverse transcription-polymerase chain reaction (RT-PCR) respectively. In the absence of lipopolysaccharide or interleukin-1 beta, ethanol treatments failed to stimulate inducible NO synthase gene expression. Lipopolysaccharide or interleukin-1 beta increased nitrite production and inducible NO synthase mRNA levels, and ethanol potentiated this effect. We concluded that ethanol could aggravate the consequences of NO generation by RBE4 cells after inducible NO synthase induction following inflammation or sepsis. This ethanol action on NO generation could contribute to circulatory failure associated with shock due to sepsis or hemorrhage, and alter blood-brain barrier permeability.
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Affiliation(s)
- M Naassila
- INSERM U295, Université de Médecine Pharmacie, Rouvray, France
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32
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Greenberg SS, Xie J, Powers DR, Giles TD. Ethanol suppresses endotoxin but not platelet activating factor-induced hypotension and nitric oxide. Alcohol Clin Exp Res 1996; 20:1260-8. [PMID: 8904980 DOI: 10.1111/j.1530-0277.1996.tb01121.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Ethanol (ETOH) inhibits the immune response to endotoxemia. The early stage of endotoxin (LPS)-induced shock is associated with an acute phase cardiovascular depression (APCD). Release of platelet activating factor (PAF) and tumor necrosis factor alpha (TNF alpha) with upregulation of nitric oxide (NO) production may initiate the APCD. Since ETOH inhibits induction of NO synthase (iNOS) mNRA by LPS, we postulate that ETOH may mask the APCD associated with endotoxemia. To test this, Sprague-Dawley rats (280-320 g, n = 5-6/group) were given LPS [0.75 mg/kg, intravenously (i.v.)] or PAF (10 to 150 micrograms/kg, i.v.) 30 min after administration of sterile saline (PBS), BN-5073 a mixed PAF antagonist (0.50 microgram/kg, i.v.), or ETOH [2.2-5.5 g/kg, intraperitoneally (i.p.)]. Cardiovascular parameters and plasma concentrations of nitrate and nitrite (RNI), ETOH, TNF alpha, and neutrophil (PMN) generation of RNI were measured. LPS and PAF both produced APCD. LPS-induced APCD was associated with tachycardia, elevated plasma TNF alpha and RNI, and ex vivo generation of RNI by PMNs. ETOH and BN-50730 prevented LPS-induced APCD and increases in RNI and TNF alpha. ETOH, however, increased the mortality associated with APCD. PAF produced only hypotension, bradycardia and elevated plasma levels of TNF alpha. ETOH and LNMMA did not affect PAF-induced APCD. BN-50730 inhibited PAF-induced APCD and plasma TNF alpha. We conclude that 1) ETOH inhibits the APCD and induction of NO characteristic of endotoxemia and 2) ETOH-induced suppression of LPS-mediated APCD may be mediated in part by suppression of release of intracellular PAF. Ethanol may increase the morbidity and mortality of endotoxemia by masking the hypotension and humoral changes characteristic of early endotoxemia thereby delaying appropriate therapy and by diminution of the protective effects of endogenous NO.
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Affiliation(s)
- S S Greenberg
- Department of Medicine, Louisiana State University Medical Center, New Orleans 70112, USA
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33
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Kowalczyk CL, Stachecki JJ, Schultz JF, Leach RE, Armant DR. Effects of alcohols on murine preimplantation development: relationship to relative membrane disordering potency. Alcohol Clin Exp Res 1996; 20:566-71. [PMID: 8727256 DOI: 10.1111/j.1530-0277.1996.tb01094.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
During in vitro culture of murine preimplantation embryos, we have observed that exposure to 0.1% ethanol induces an immediate increase in intracellular calcium levels and subsequently accelerates embryogenesis. If the observed effects of ethanol on developing embryos is mediated by its membrane disordering potency, we hypothesized that the relative membrane disordering potencies of related alcohols would correspondingly effect embryonic intracellular calcium levels and developmental rates. Two-cell embryos were exposed to 0.1% ethanol or 0.05 to 1.0% (w/v) n-butanol, n-propanol, isopropanol, 1,2-propanediol, glycerol, or methanol for 24 hr at 37 degrees C, and development to the blastocyst stage was monitored after 5 days. n-Butanol, n-propanol, isopropanol, and methanol treatment caused a dose-dependent inhibition (p < 0.01) of development to the blastocyst stage, whereas 1,2-propanediol or glycerol neither accelerated nor inhibited development. In a second experiment, 8-cell morulae were treated with 1,2-propanediol or glycerol, and cavitation rates were examined. There was no significant difference from control embryos in the onset of cavitation or the blastocoel expansion rate of 1,2-propanediol- or glycerol-exposed embryos, whereas exposure to 0.1% ethanol accelerate cavitation (p > 0.05). In a third experiment, morulae were exposed to 0.1% or 1.0% of each alcohol and were monitored for changes in intracellular calcium levels using the fluorescent indicator, fluo-3-acetoxymethyl ester. There was an immediate increase in intracellular calcium levels when morulae were treated with 1.0% ethanol or n-butanol, but only ethanol induced an increase (p < 0.05) in the level of intracellular calcium at 0.1%. These data suggest that ethanol is unique in its ability to accelerate embryogenesis and that the membrane disordering potency of ethanol does not directly underlie its effects on intracellular calcium release and the acceleration of preimplantation development.
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Affiliation(s)
- C L Kowalczyk
- C. S. Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan 48201, USA
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