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Design and Synthesis of New Acridone-Based Nitric Oxide Fluorescent Probe. Molecules 2021; 26:molecules26144340. [PMID: 34299615 PMCID: PMC8307419 DOI: 10.3390/molecules26144340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 11/23/2022] Open
Abstract
Nitric oxide (NO) is an important signaling molecule involved in a wide range of physiological and pathological processes. Fluorescent imaging is a useful tool for monitoring NO concentration, which could be essential in various biological and biochemical studies. Here, we report the design of a novel small-molecule fluorescent probe based on 9(10H)acridone moiety for nitric oxide sensing. 7,8-Diamino-4-carboxy-10-methyl-9(10H)acridone reacts with NO in aqueous media in the presence of O2, yielding a corresponding triazole derivative with fivefold increased fluorescence intensity. The probe was shown to be capable of nitric oxide sensing in living Jurkat cells.
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2
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Biglycan: A regulator of hepatorenal inflammation and autophagy. Matrix Biol 2021; 100-101:150-161. [DOI: 10.1016/j.matbio.2021.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/03/2021] [Accepted: 06/04/2021] [Indexed: 02/07/2023]
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Brüning CA, Rosa SG, Quines CB, Magni DV, Nonemacher NT, Bortolatto CF, Nogueira CW. The role of nitric oxide in glutaric acid-induced convulsive behavior in pup rats. Eur J Neurosci 2020; 52:3738-3745. [PMID: 32459863 DOI: 10.1111/ejn.14840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/27/2020] [Accepted: 05/18/2020] [Indexed: 12/26/2022]
Abstract
Glutaric acidaemia type I (GA-I) is a cerebral organic disorder characterized by the accumulation of glutaric acid (GA) and seizures. As seizures are precipitated in children with GA-I and the mechanisms underlying this disorder are not well established, we decided to investigate the role of nitric oxide (NO) in GA-induced convulsive behaviour in pup rats. Pup male Wistar rats (18-day-old) were anesthetized and placed in stereotaxic apparatus for cannula insertion into the striatum for injection of GA. The experiments were performed 3 days after surgery (pup rats 21-day-old). An inhibitor of NO synthesis (N-G-nitro-l-arginine methyl ester-L-NAME, 40 mg/kg) or saline (vehicle) was administered intraperitoneally 30 min before the intrastriatal injection of GA (1 µl, 1.3 µmol/striatum) or saline. Immediately after the intrastriatal injections, the latency and duration of seizures were recorded for 20 min. The administration of L-NAME significantly increased the latency to the first seizure episode and reduced the duration of seizures induced by GA in pup rats. The administration of the NO precursor l-arginine (L-ARG; 80 mg/kg) prevented the effects of L-NAME. Besides, GA significantly increased nitrate and nitrite (NOx) levels in the striatum of pup rats and the preadministration of L-NAME prevented this alteration. L-ARG blocked the reduction of striatal NOx provoked by L-NAME. These results are experimental evidence that NO plays a role in the seizures induced by GA in pup rats, being valuable in understanding the physiopathology of neurological signs observed in children with this organic acidaemia and to develop new therapeutic strategies.
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Affiliation(s)
- César Augusto Brüning
- Laboratory of Biochemistry and Molecular Neuropharmacology (LABIONEM), Neurobiotechnology Research Group, Postgraduate Program in Biochemistry and Bioprospecting (PPGBBio), Center for Chemical, Pharmaceutical and Food Sciences (CCQFA), Federal University of Pelotas (UFPel), Pelotas, Brazil
| | - Suzan Gonçalves Rosa
- Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Federal University of Santa Maria (UFSM), Brazil
| | - Caroline Brandão Quines
- Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Federal University of Santa Maria (UFSM), Brazil
| | - Danieli Valnes Magni
- Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Federal University of Santa Maria (UFSM), Brazil
| | - Natália Tavares Nonemacher
- Laboratory of Biochemistry and Molecular Neuropharmacology (LABIONEM), Neurobiotechnology Research Group, Postgraduate Program in Biochemistry and Bioprospecting (PPGBBio), Center for Chemical, Pharmaceutical and Food Sciences (CCQFA), Federal University of Pelotas (UFPel), Pelotas, Brazil
| | - Cristiani Folharini Bortolatto
- Laboratory of Biochemistry and Molecular Neuropharmacology (LABIONEM), Neurobiotechnology Research Group, Postgraduate Program in Biochemistry and Bioprospecting (PPGBBio), Center for Chemical, Pharmaceutical and Food Sciences (CCQFA), Federal University of Pelotas (UFPel), Pelotas, Brazil
| | - Cristina Wayne Nogueira
- Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Departamento de Bioquímica e Biologia Molecular, Centro de Ciências Naturais e Exatas, Federal University of Santa Maria (UFSM), Brazil
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Dyer RR, Ford KI, Robinson RAS. The roles of S-nitrosylation and S-glutathionylation in Alzheimer's disease. Methods Enzymol 2019; 626:499-538. [PMID: 31606089 PMCID: PMC6908309 DOI: 10.1016/bs.mie.2019.08.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) is a debilitating dementia with complex pathophysiological alterations including modifications to endogenous cysteine. S-nitrosylation (SNO) is a well-studied posttranslational modification (PTM) in the context of AD while S-glutathionylation (PSSG) remains less studied. Excess reactive oxygen and reactive nitrogen species (ROS/RNS) directly or indirectly generate SNO and PSSG. SNO is dysregulated in AD and plays a pervasive role in processes such as protein function, cell signaling, metabolism, and apoptosis. Despite some studies into the role of SNO in AD, multiple identified SNO proteins lack deep investigation and SNO modifications outside of brain tissues are limited, leaving the full role of SNO in AD to be elucidated. PSSG homeostasis is perturbed in AD and may affect a myriad of cellular processes. Here we overview the role of nitric oxide (NO) in AD, discuss proteomic methodologies to investigate SNO and PSSG, and review SNO and PSSG in AD. A more thorough understanding of SNO, PSSG, and other cysteinyl PTMs in AD will be helpful for the development of novel therapeutics against neurodegenerative diseases.
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Affiliation(s)
- Ryan R Dyer
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Katarena I Ford
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Renã A S Robinson
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States; Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Memory & Alzheimer's Center, Nashville, TN, United States; Vanderbilt Institute of Chemical Biology, Nashville, TN, United States; Vanderbilt Brain Institute, Nashville, TN, United States.
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5
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Barak OF, Caljkusic K, Hoiland RL, Ainslie PN, Thom SR, Yang M, Jovanov P, Dujic Z. Differential influence of vitamin C on the peripheral and cerebral circulation after diving and exposure to hyperoxia. Am J Physiol Regul Integr Comp Physiol 2018; 315:R759-R767. [PMID: 29995458 DOI: 10.1152/ajpregu.00412.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We examined if the diving-induced vascular changes in the peripheral and cerebral circulation could be prevented by oral antioxidant supplementation. Fourteen divers performed a single scuba dive to eighteen meter sea water for 47 min. Twelve of the divers participated in a follow-up study involving breathing 60% of oxygen at ambient pressure for 47 min. Before both studies, participants ingested vitamin C (2 g/day) or a placebo capsule for 6 days. After a 2-wk washout, the study was repeated with the different condition. Endothelium-dependent vasodilator function of the brachial artery was assessed pre- and postintervention using the flow-mediated dilation (FMD) technique. Transcranial Doppler ultrasound was used to measure intracranial blood velocities pre- and 90 min postintervention. FMD was reduced by ∼32.8% and ∼21.2% postdive in the placebo and vitamin C trial and posthyperoxic condition in the placebo trial by ∼28.2% ( P < 0.05). This reduction in FMD was attenuated by ∼10% following vitamin C supplementation in the hyperoxic study ( P > 0.05). Elevations in intracranial blood velocities 30 min after surfacing from diving were reduced in the vitamin C study compared with the placebo trial ( P < 0.05). O2 breathing had no postintervention effects on intracranial velocities ( P > 0.05). Prophylactic ingestion of vitamin C effectively abrogated peripheral vascular dysfunction following exposure to 60% O2 but did not abolish the postdive decrease in FMD. Transient elevations of intracranial velocities postdive were reduced by vitamin C. These findings highlight the differential influence of vitamin C on peripheral and cerebral circulations following scuba diving, which are only partly mediated via hyperoxia.
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Affiliation(s)
- Otto F Barak
- Department of Physiology, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia.,Faculty of Sports and Physical Education, University of Novi Sad, Novi Sad, Serbia
| | - Kresimir Caljkusic
- Department of Neurology, University Hospital Centre Split , Split , Croatia
| | - Ryan L Hoiland
- Centre for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan Campus, Kelowna, BC , Canada
| | - Philip N Ainslie
- Centre for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan Campus, Kelowna, BC , Canada
| | - Stephen R Thom
- Department of Emergency Medicine, University of Maryland School of Medicine , Baltimore, Maryland
| | - Ming Yang
- Department of Emergency Medicine, University of Maryland School of Medicine , Baltimore, Maryland
| | - Pavle Jovanov
- Institute of Food Technology in Novi Sad, University of Novi Sad, Novi Sad, Serbia
| | - Zeljko Dujic
- Department of Integrative Physiology, University of Split School of Medicine , Split , Croatia
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Guerra GP, Rubin MA, Mello CF. Modulation of learning and memory by natural polyamines. Pharmacol Res 2016; 112:99-118. [PMID: 27015893 DOI: 10.1016/j.phrs.2016.03.023] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 03/09/2016] [Accepted: 03/11/2016] [Indexed: 01/08/2023]
Abstract
Spermine and spermidine are natural polyamines that are produced mainly via decarboxylation of l-ornithine and the sequential transfer of aminopropyl groups from S-adenosylmethionine to putrescine by spermidine synthase and spermine synthase. Spermine and spermidine interact with intracellular and extracellular acidic residues of different nature, including nucleic acids, phospholipids, acidic proteins, carboxyl- and sulfate-containing polysaccharides. Therefore, multiple actions have been suggested for these polycations, including modulation of the activity of ionic channels, protein synthesis, protein kinases, and cell proliferation/death, within others. In this review we summarize these neurochemical/neurophysiological/morphological findings, particularly those that have been implicated in the improving and deleterious effects of spermine and spermidine on learning and memory of naïve animals in shock-motivated and nonshock-motivated tasks, from a historical perspective. The interaction with the opioid system, the facilitation and disruption of morphine-induced reward and the effect of polyamines and putative polyamine antagonists on animal models of cognitive diseases, such as Alzheimer's, Huntington, acute neuroinflammation and brain trauma are also reviewed and discussed. The increased production of polyamines in Alzheimer's disease and the biphasic nature of the effects of polyamines on memory and on the NMDA receptor are also considered. In light of the current literature on polyamines, which include the description of an inborn error of the metabolism characterized by mild-to moderate mental retardation and polyamine metabolism alterations in suicide completers, we can anticipate that polyamine targets may be important for the development of novel strategies and approaches for understanding the etiopathogenesis of important central disorders and their pharmacological treatment.
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Affiliation(s)
- Gustavo Petri Guerra
- Department of Food Technology, Federal Technological University of Paraná, Campus Medianeira, Medianeira, PR 85884-000, Brazil
| | - Maribel Antonello Rubin
- Department of Biochemistry, Center of Exact and Natural Sciences, Federal University of Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil.
| | - Carlos Fernando Mello
- Department of Physiology and Pharmacology, Center of Health Sciences, Federal University of Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil.
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Vucinovic Z, Duplancic D, Seselja-Perisin A, Kukoc-Modun L, Gunjaca G, Radman M, Vukovic J, Tsikas D, Poljak K, Modun D. Acute application of antioxidants protects against hyperoxia-induced reduction of plasma nitrite concentration. Clin Physiol Funct Imaging 2014; 35:76-80. [PMID: 24863414 DOI: 10.1111/cpf.12169] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 04/28/2014] [Indexed: 11/29/2022]
Abstract
We investigated the effects of acute intake of antioxidants on hyperoxia-induced oxidative stress, reduction of plasma nitrite and change in arterial stiffness. Twelve healthy males randomly consumed either placebo or an oral antioxidant cocktail (vitamin C, 1000 mg; vitamin E, 600 IU; alpha-lipoic acid, 600 mg). Every therapy was consumed once, a week apart, in a cross-over design, 30 min before the experiment. The volunteers breathed 100% normobaric oxygen between 30th and 60th min of 1-h study protocol. Plasma levels of nitrite, lipid peroxides (LOOH) and vitamin C, arterial stiffness (indicated by augmentation index, AIx) and arterial oxygen (Ptc O2 ) pressure were measured before and after hyperoxia. Exposure to oxygen caused a similar increase of Ptc O2 in both placebo and antioxidants groups, confirming comparable exposure to hyperoxia (438 ± 100 versus 455 ± 83 mm Hg). Vitamin C was increased in the antioxidants group confirming successful application of antioxidants (69 ± 14 versus 57 ± 15 μm). Hyperoxia resulted in increased AIx and LOOH and decreased nitrite in placebo (-32 ± 11 versus -47 ± 13%, 72 ± 7 versus 62 ± 6 μm H2 O2 and 758 ± 184 versus 920 ± 191 nm, respectively), but not in the antioxidants group (-42 ± 13 versus -50 ± 13%, 64 ± 9 versus 61 ± 8 μm H2 O2 and 847 ± 156 versus 936 ± 201 nm, respectively). The acute intake of selected antioxidants was effective in preserving bioavailabity of ˙NO and vascular function, against hyperoxia-induced oxidative stress.
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Affiliation(s)
- Zoran Vucinovic
- Department of Internal Medicine, University Hospital Split, Split, Croatia
| | - Darko Duplancic
- Department of Internal Medicine, University Hospital Split, Split, Croatia
| | - Ana Seselja-Perisin
- Department of Pharmacology, University of Split School of Medicine, Split, Croatia
| | - Lea Kukoc-Modun
- Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Split, Croatia
| | - Grgo Gunjaca
- Department of Pharmacology, University of Split School of Medicine, Split, Croatia
| | - Maja Radman
- Department of Internal Medicine, University Hospital Split, Split, Croatia
| | - Jonatan Vukovic
- Department of Internal Medicine, University Hospital Split, Split, Croatia
| | - Dimitrios Tsikas
- Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany
| | - Kolja Poljak
- Department of Otorhinolaryngology, University Hospital Split, Split, Croatia
| | - Darko Modun
- Department of Pharmacology, University of Split School of Medicine, Split, Croatia
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Plasma levels of aminothiols, nitrite, nitrate, and malondialdehyde in myelodysplastic syndromes in the context of clinical outcomes and as a consequence of iron overload. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:416028. [PMID: 24669287 PMCID: PMC3942103 DOI: 10.1155/2014/416028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/15/2013] [Accepted: 12/18/2013] [Indexed: 01/21/2023]
Abstract
The role of oxidative stress in the initiation and progression of myelodysplastic syndromes (MDS) as a consequence of iron overload remains unclear. In this study we have simultaneously quantified plasma low-molecular-weight aminothiols, malondialdehyde, nitrite, and nitrate and have studied their correlation with serum iron/ferritin levels, patient treatment (chelation therapy), and clinical outcomes. We found significantly elevated plasma levels of total, oxidized, and reduced forms of cysteine (P < 0.001)
, homocysteine (P < 0.001),
and cysteinylglycine (P < 0.006)
and significantly depressed levels of total and oxidized forms of glutathione (P < 0.03)
and nitrite (P < 0.001)
in MDS patients compared to healthy donors. Moreover, total (P < 0.032)
and oxidized cysteinylglycine (P = 0.029)
and nitrite (P = 0.021)
differed significantly between the analyzed MDS subgroups with different clinical classifications. Malondialdehyde levels in plasma correlated moderately with both serum ferritin levels (r = 0.78, P = 0.001)
and serum free iron levels (r = 0.60, P = 0.001)
and were significantly higher in patients with iron overload. The other analyzed compounds lacked correlation with iron overload (represented by serum iron/ferritin levels). For the first time our results have revealed significant differences in the concentrations of plasma aminothiols in MDS patients, when compared to healthy donors. We found no correlation of these parameters with iron overload and suggest the role of oxidative stress in the development of MDS disease.
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Effects of L-arginine and N(ω)-nitro-L-arginine methylester on learning and memory and α7 nAChR expression in the prefrontal cortex and hippocampus of rats. Neurosci Bull 2013; 29:303-10. [PMID: 23575895 DOI: 10.1007/s12264-013-1331-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 10/23/2012] [Indexed: 12/22/2022] Open
Abstract
Nitric oxide (NO) is a novel type of neurotransmitter that is closely associated with synaptic plasticity, learning and memory. In the present study, we assessed the effects of L-arginine and N(ω)-nitro-L-arginine methylester (L-NAME, a nitric oxide synthase inhibitor) on learning and memory. Rats were assigned to three groups receiving intracerebroventricular injections of L-Arg (the NO precursor), L-NAME, or 0.9% NaCl (control), once daily for seven consecutive days. Twelve hours after the last injection, they underwent an electric shock-paired Y maze test. Twenty-four hours later, the rats' memory of the safe illuminated arm was tested. After that, the levels of NO and α7 nicotinic acetylcholine receptor (α7 nAChR) in the prefrontal cortex and hippocampus were assessed using an NO assay kit, and immunohistochemistry and Western blots, respectively. We found that, compared to controls, L-Arg-treated rats received fewer foot shocks and made fewer errors to reach the learning criterion, and made fewer errors during the memory-testing session. In contrast, L-NAME-treated rats received more foot shocks and made more errors than controls to reach the learning criterion, and made more errors during the memory-testing session. In parallel, NO content in the prefrontal cortex and hippocampus was higher in L-Arg-treated rats and lower in L-NAME rats, compared to controls. Similarly, α7 nAChR immunoreactivity and protein expression in the prefrontal cortex and hippocampus were higher in L-Arg-treated rats and lower in L-NAME rats, compared to controls. These results suggest that the modulation of NO content in the brain correlates with α7 nAChR distribution and expression in the prefrontal cortex and hippocampus, as well as with learning and memory performance in the Y-maze.
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Huang X, Zhou Y, Ma J, Wang N, Zhang Z, Ji J, Ding Q, Chen G. Nitric oxide mediated effects on reproductive toxicity caused by carbon disulfide in male rats. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2012; 34:679-687. [PMID: 23146592 DOI: 10.1016/j.etap.2012.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 09/29/2012] [Accepted: 10/05/2012] [Indexed: 06/01/2023]
Abstract
This study investigated nitric oxide (NO) mediation of carbon disulfide (CS(2)) toxicity that compromised male rat spermatogenesis and endocrine function. Rats were exposed to multiple levels of CS(2) concentration (0, 50, 250, 1250 mg/m(3)). A 1250 mg/m(3) CS(2)+sodium nitroprusside (SNP) group and a 1250 mg/m(3) CS(2)+NG-monomethyl-L-arginine (L-NMMA) group were established to explore the role of NO in mediating CS(2) toxicity. NO concentrations, NO synthase (NOS) activity, and sex hormone levels were measured, and sperm characteristics were observed and analyzed. Our data show that CS(2) exposure decreased: NOS activity; tissue NO concentrations; serum levels of gonadotropin-releasing hormones, luteinizing hormones, and testosterone; and sperm count and activity. In contrast, increased serum follicle-stimulating hormone concentrations and teratospermia were observed with CS(2) exposure. SNP reduced some of the toxic effects of CS(2), while L-NMMA treatment showed no effect. The results suggests that NO mediates compromised reproductive system function caused by CS(2) exposure.
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Affiliation(s)
- Xiaoyu Huang
- MOE Key Lab of Environment and Health, Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, Hubei, PR China
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Modun D, Krnic M, Vukovic J, Kokic V, Kukoc-Modun L, Tsikas D, Dujic Z. Plasma nitrite concentration decreases after hyperoxia-induced oxidative stress in healthy humans. Clin Physiol Funct Imaging 2012; 32:404-8. [PMID: 22856349 DOI: 10.1111/j.1475-097x.2012.01133.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 03/15/2012] [Indexed: 11/28/2022]
Abstract
The aim of this study was to measure plasma nitrite, the biochemical marker of endothelial nitric oxide ((•)NO) synthesis, before and after hyperoxia, in order to test the hypothesis that hyperoxia-induced vasoconstriction is a consequence of reduced bioavailability of (•)NO caused by elevated oxidative stress. Ten healthy men breathed 100% normobaric O(2) for 30 min between 15th and 45th min of the 1-h study protocol. Plasma nitrite and malondialdehyde (MDA), arterial stiffness (indicated by augmentation index, AIx) and arterial oxygen (P(tc)O(2)) pressure were measured at 1st, 15th, 45th and 60th minute of the study. Breathing of normobaric 100% oxygen during 30 min caused an increase in P(tc)O(2) (from 75 ± 2 to 412 ± 25 mm Hg), AIx (from -63 ± 4 to -51 ± 3%) and MDA (from 152 ± 13 to 218 ± 15 nm) values and a decrease in plasma nitrite (from 918 ± 58 to 773 ± 55 nm). During the 15-min recovery phase, plasma nitrite, AIx and MDA values remained altered. This study suggests that the underlying mechanism of hyperoxia-induced vasoconstriction may involve reduced (•)NO bioavailability caused by elevated and sustained oxidative stress.
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Affiliation(s)
- Darko Modun
- Department of Pharmacology, University of Split School of Medicine, Split, Croatia.
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Gao Z, Spilk S, Momen A, Muller MD, Leuenberger UA, Sinoway LI. Vitamin C prevents hyperoxia-mediated coronary vasoconstriction and impairment of myocardial function in healthy subjects. Eur J Appl Physiol 2012; 112:483-92. [PMID: 21584682 PMCID: PMC3281262 DOI: 10.1007/s00421-011-1997-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 05/02/2011] [Indexed: 11/25/2022]
Abstract
Supplementary oxygen is commonly administered in current medical practice. Recently it has been suggested that hyperoxia causes acute oxidative stress and produces prompt and substantial changes in coronary resistance in patients with ischemic heart disease. In this report, we examined whether the effects of hyperoxia on coronary blood velocity (CBV) would be associated with a reduction in myocardial function. We were also interested in determining if the postulated changes in left ventricular (LV) function seen with tissue Doppler imaging (TDI) could be reversed with intravenous vitamin C, a potent, acute anti-oxidant. LV function was determined in eight healthy subjects with transthoracic echocardiography and TDI before and after hyperoxia and with and without infusing vitamin C. Hyperoxia compared with room air promptly reduced CBV by 28 ± 3% (from 23.50 ± 2.31 cm/s down to 17.00 ± 1.79 cm/s) and increased relative coronary resistance by 34 ± 5% (from 5.63 ± 0.88 up to 7.32 ± 0.94). Meanwhile, LV myocardial systolic velocity decreased by 11 ± 6% (TDI). These effects on flow and function were eliminated by the infusion of vitamin C, suggesting that these changes are mediated by vitamin C-quenchable substances acting on the coronary microcirculation.
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Affiliation(s)
- Zhaohui Gao
- Penn State Heart and Vascular Institute, H047, Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
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Hosseini M, Nemati Karimooy H, Hadjzadeh M, Safari V. Inducible nitric oxide synthase inhibitor aminoguanidine, differently affects Morris water maze tasks of ovariectomized and naïve female rats. ACTA ACUST UNITED AC 2011; 98:421-32. [DOI: 10.1556/aphysiol.98.2011.4.5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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14
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Krnic M, Modun D, Budimir D, Gunjaca G, Jajic I, Vukovic J, Salamunic I, Sutlovic D, Kozina B, Boban M. Comparison of acute effects of red wine, beer and vodka against hyperoxia-induced oxidative stress and increase in arterial stiffness in healthy humans. Atherosclerosis 2011; 218:530-5. [PMID: 21803358 DOI: 10.1016/j.atherosclerosis.2011.07.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 07/01/2011] [Accepted: 07/04/2011] [Indexed: 01/08/2023]
Abstract
OBJECTIVE We determined and compared acute effects of different alcoholic beverages on oxygen-induced increase in oxidative stress plasma marker and arterial stiffness in healthy humans. METHODS Ten males randomly consumed one of four tested beverages: red wine (RW), vodka, beer (0.32 g ethanol/kg body wt) and water as control. Every beverage was consumed once, a week apart, in a cross-over design. The volunteers breathed 100% normobaric O(2) between 60th and 90th min of 3h study protocol. Plasma lipid peroxides (LOOH) and uric acid (UA) concentration, blood alcohol concentration (BAC) and arterial stiffness (indicated by augmentation index, AIx) were measured before and 30, 60, 90, 120 and 180 min after beverage consumption. RESULTS Intake of all alcoholic beverages caused a similar increase of BAC. The oxygen-induced elevation in AIx was similarly reduced in all three groups relative to the control (3.4 ± 1.3%, 5.4 ± 2.2% and 0.2 ± 1.6% vs. 13.7 ± 2.6% for red wine, vodka, beer and control, respectively, 60 min after intake). Exposure to oxygen resulted in increased plasma LOOH in all groups. However, in RW group this increase was lowest (1.1 ± 0.5) in comparison to the vodka (2.1 ± 0.5), beer (1.6±0.3) and control (2.5 ± 0.4μM/L H(2)O(2)). 60 min after intake of RW and beer plasma UA significantly increased (34 ± 4 and 15 ± 3) in contrast to vodka and control (-6 ± 2 and -8 ± 2μmol/L). CONCLUSION All three alcoholic beverages provided similar protection against oxygen-induced increase in arterial stiffness, probably due to central vasodilatatory effect of alcohol itself, but only RW provided protection against oxygen-induced oxidative stress.
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Affiliation(s)
- Mladen Krnic
- Department of Endocrinology, University Hospital Split, Soltanska 1, Split, Croatia
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Obad A, Marinovic J, Ljubkovic M, Breskovic T, Modun D, Boban M, Dujic Z. Successive deep dives impair endothelial function and enhance oxidative stress in man. Clin Physiol Funct Imaging 2010; 30:432-8. [DOI: 10.1111/j.1475-097x.2010.00962.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Anti-neuroinflammatory activity of 1,5-benzodiazepine derivatives. Bioorg Med Chem Lett 2010; 20:3969-71. [DOI: 10.1016/j.bmcl.2010.04.133] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 04/21/2010] [Accepted: 04/28/2010] [Indexed: 11/21/2022]
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17
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Lourenço CF, Santos R, Barbosa RM, Gerhardt G, Cadenas E, Laranjinha J. In vivo modulation of nitric oxide concentration dynamics upon glutamatergic neuronal activation in the hippocampus. Hippocampus 2010; 21:622-30. [DOI: 10.1002/hipo.20774] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2009] [Indexed: 11/07/2022]
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18
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Vukovic J, Modun D, Budimir D, Sutlovic D, Salamunic I, Zaja I, Boban M. Acute, food-induced moderate elevation of plasma uric acid protects against hyperoxia-induced oxidative stress and increase in arterial stiffness in healthy humans. Atherosclerosis 2009; 207:255-60. [DOI: 10.1016/j.atherosclerosis.2009.04.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 04/02/2009] [Accepted: 04/07/2009] [Indexed: 02/04/2023]
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19
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DeWitt DS, Prough DS. Blast-induced brain injury and posttraumatic hypotension and hypoxemia. J Neurotrauma 2009; 26:877-87. [PMID: 18447627 DOI: 10.1089/neu.2007.0439] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Explosive munitions account for more than 50% of all wounds sustained in military combat, and the proportion of civilian casualties due to explosives is increasing as well. But there has been only limited research on the pathophysiology of blast-induced brain injury, and the contributions of alterations in cerebral blood flow (CBF) or cerebral vascular reactivity to blast-induced brain injury have not been investigated. Although secondary hypotension and hypoxemia are associated with increased mortality and morbidity after closed head injury, the effects of secondary insults on outcome after blast injury are unknown. Hemorrhage accounted for approximately 50% of combat deaths, and the lungs are one of the primary organs damaged by blast overpressure. Thus, it is likely that blast-induced lung injury and/or hemorrhage leads to hypotensive and hypoxemic secondary injury in a significant number of combatants exposed to blast overpressure injury. Although the effects of blast injury on CBF and cerebral vascular reactivity are unknown, blast injury may be associated with impaired cerebral vascular function. Reactive oxygen species (ROS) such as the superoxide anion radical and other ROS, likely major contributors to traumatic cerebral vascular injury, are produced by traumatic brain injury (TBI). Superoxide radicals combine with nitric oxide (NO), another ROS produced by blast injury as well as other types of TBI, to form peroxynitrite, a powerful oxidant that impairs cerebral vascular responses to reduced intravascular pressure and other cerebral vascular responses. While current research suggests that blast injury impairs cerebral vascular compensatory responses, thereby leaving the brain vulnerable to secondary insults, the effects of blast injury on the cerebral vascular reactivity have not been investigated. It is clear that further research is necessary to address these critical concerns.
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Affiliation(s)
- Douglas S DeWitt
- Moody Center for Traumatic Brain & Spinal Cord Injury Research, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0830, USA.
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20
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da Cunha FM, Duma D, Assreuy J, Buzzi FC, Niero R, Campos MM, Calixto JB. Caffeic Acid Derivatives: In Vitro and In Vivo Anti-inflammatory Properties. Free Radic Res 2009; 38:1241-53. [PMID: 15621702 DOI: 10.1080/10715760400016139] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Caffeic acid and some of its derivatives such as caffeic acid phenetyl ester (CAPE) and octyl caffeate are potent antioxidants which present important anti-inflammatory actions. The present study assessed the in vitro and in vivo effects of five caffeic acid derivatives (caffeic acid methyl, ethyl, butyl, octyl and benzyl esters) and compared their actions to those of CAPE. In the model of LPS-induced nitric oxide (NO) production in RAW 264.7 macrophages, the pre-incubation of all derivatives inhibited nitrite accumulation on the supernatant of stimulated cells, with mean IC50 (microM) values of 21.0, 12.0, 8.4, 2.4, 10.7 and 4.80 for methyl, ethyl, butyl, octyl, benzyl and CAPE, respectively. The effects of caffeic acid derivatives seem to be related to the scavenging of NO, as the compounds prevented SNAP-derived nitrite accumulation and decreased iNOS expression. In addition, butyl, octyl and CAPE derivatives significantly inhibited LPS-induced iNOS expression in RAW 264.7 macrophages. Extending the in vitro results, we showed that the pre-treatment of mice with butyl, octyl and CAPE derivatives inhibited carrageenan-induced paw edema and prevented the increase in IL-1beta levels in the mouse paw by 30, 24 and 36%, respectively. Butyl, octyl and CAPE derivatives also prevented carrageenan-induced neutrophil influx in the mouse paw by 28, 49 and 31%, respectively. Present results confirm and extend literature data, showing that caffeic acid derivatives exert in vitro and in vivo anti-inflammatory actions, being their actions mediated, at least in part by the scavenging of NO and their ability to modulate iNOS expression and probably that of other inflammatory mediators.
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Affiliation(s)
- Fernanda M da Cunha
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário, Trindade 88049-900, Florianópolis, SC, Brazil
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21
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Rőszer T, Józsa T, Szentmiklósi AJ, Bánfalvi G. Acetylcholine inhibits nitric oxide (NO) synthesis in the gastropod nervous system. Cell Tissue Res 2009; 336:325-35. [DOI: 10.1007/s00441-009-0764-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Accepted: 01/13/2009] [Indexed: 12/16/2022]
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22
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Effects of carbon disulfide on the expression and activity of nitric oxide synthase in rat hippocampus. Chin Med J (Engl) 2008. [DOI: 10.1097/00029330-200812020-00015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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23
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Korda M, Kubant R, Patton S, Malinski T. Leptin-induced endothelial dysfunction in obesity. Am J Physiol Heart Circ Physiol 2008; 295:H1514-21. [PMID: 18689498 DOI: 10.1152/ajpheart.00479.2008] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hyperleptinemia accompanying obesity affects endothelial nitric oxide (NO) and is a serious factor for vascular disorders. NO, superoxide (O(2)(-)), and peroxynitrite (ONOO(-)) nanosensors were placed near the surface (5+/-2 microm) of a single human umbilical vein endothelial cell (HUVEC) exposed to leptin or aortic endothelium of obese C57BL/6J mice, and concentrations of calcium ionophore (CaI)-stimulated NO, O(2)(-), ONOO(-) were recorded. Endothelial NO synthase (eNOS) expression and L-arginine concentrations in HUVEC and aortic endothelium were measured. Leptin did not directly stimulate NO, O(2)(-), or ONOO(-) release from HUVEC. However, a 12-h exposure of HUVEC to leptin increased eNOS expression and CaI-stimulated NO (625+/-30 vs. 500+/-24 nmol/l control) and dramatically increased cytotoxic O(2)(-) and ONOO(-) levels. The [NO]-to-[ONOO(-)] ratio ([NO]/[ONOO(-)]) decreased from 2.0+/-0.1 in normal to 1.30+/-0.1 in leptin-induced dysfunctional endothelium. In obese mice, a 2.5-fold increase in leptin concentration coincided with 100% increase in eNOS and about 30% decrease in intracellular L-arginine. The increased eNOS expression and a reduced l-arginine content led to eNOS uncoupling, a reduction in bioavailable NO (250+/-10 vs. 420+/-12 nmol/l control), and an elevated concentration of O(2)(-) (240%) and ONOO(-) (70%). L-Arginine and sepiapterin supplementation reversed eNOS uncoupling and partially restored [NO]/[ONOO(-)] balance in obese mice. In obesity, leptin increases eNOS expression and decreases intracellular l-arginine, resulting in eNOS an uncoupling and depletion of endothelial NO and an increase of cytotoxic ONOO(-). Hyperleptinemia triggers an endothelial NO/ONOO(-) imbalance characteristic of dysfunctional endothelium observed in other vascular disorders, i.e., atherosclerosis and diabetes.
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Affiliation(s)
- Mykhaylo Korda
- Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701-2979, USA
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24
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Korda M, Kubant R, Patton S, Malinski T. Leptin-induced endothelial dysfunction in obesity. Am J Physiol Heart Circ Physiol 2008. [PMID: 18689498 DOI: 10.1152/ajpheart.00479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hyperleptinemia accompanying obesity affects endothelial nitric oxide (NO) and is a serious factor for vascular disorders. NO, superoxide (O(2)(-)), and peroxynitrite (ONOO(-)) nanosensors were placed near the surface (5+/-2 microm) of a single human umbilical vein endothelial cell (HUVEC) exposed to leptin or aortic endothelium of obese C57BL/6J mice, and concentrations of calcium ionophore (CaI)-stimulated NO, O(2)(-), ONOO(-) were recorded. Endothelial NO synthase (eNOS) expression and L-arginine concentrations in HUVEC and aortic endothelium were measured. Leptin did not directly stimulate NO, O(2)(-), or ONOO(-) release from HUVEC. However, a 12-h exposure of HUVEC to leptin increased eNOS expression and CaI-stimulated NO (625+/-30 vs. 500+/-24 nmol/l control) and dramatically increased cytotoxic O(2)(-) and ONOO(-) levels. The [NO]-to-[ONOO(-)] ratio ([NO]/[ONOO(-)]) decreased from 2.0+/-0.1 in normal to 1.30+/-0.1 in leptin-induced dysfunctional endothelium. In obese mice, a 2.5-fold increase in leptin concentration coincided with 100% increase in eNOS and about 30% decrease in intracellular L-arginine. The increased eNOS expression and a reduced l-arginine content led to eNOS uncoupling, a reduction in bioavailable NO (250+/-10 vs. 420+/-12 nmol/l control), and an elevated concentration of O(2)(-) (240%) and ONOO(-) (70%). L-Arginine and sepiapterin supplementation reversed eNOS uncoupling and partially restored [NO]/[ONOO(-)] balance in obese mice. In obesity, leptin increases eNOS expression and decreases intracellular l-arginine, resulting in eNOS an uncoupling and depletion of endothelial NO and an increase of cytotoxic ONOO(-). Hyperleptinemia triggers an endothelial NO/ONOO(-) imbalance characteristic of dysfunctional endothelium observed in other vascular disorders, i.e., atherosclerosis and diabetes.
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Affiliation(s)
- Mykhaylo Korda
- Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701-2979, USA
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25
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Hoetzel A, Welle A, Schmidt R, Loop T, Humar M, Ryter SW, Geiger KK, Choi AMK, Pannen BHJ. Nitric oxide-deficiency regulates hepatic heme oxygenase-1. Nitric Oxide 2007; 18:61-9. [PMID: 17999922 DOI: 10.1016/j.niox.2007.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 10/18/2007] [Accepted: 10/21/2007] [Indexed: 02/02/2023]
Abstract
Nitric oxide plays a crucial role in the maintenance of liver function and integrity. During stress, the inducible heme oxygenase-1 protein and its reaction products, including carbon monoxide, also exert potent hepatoprotective effects. We investigated a potential relationship between endogenous nitric oxide synthesis and the hepatic regulation of heme oxygenase-1. Inhibition of nitric oxide synthesis in vivo by injection of l-NAME led to a dose-dependent induction of heme oxygenase-1 mRNA, protein and activity in the rat liver, whereas did not affect the expression of other heat shock proteins. The effect of l-NAME was demonstrated by hemodynamic changes within the liver circulation as measured by ultrasonic flow probes. Inhibition of nitric oxide synthase led to a decline in hepatic arterial and portal venous blood flow, and subsequently caused liver cell damage. In contrast, the combined administration of l-NAME and the nitric oxide-independent intestinal vasodilator dihydralazine completely restored portal venous flow, abolished the liver cell damage, and prevented the upregulation of heme oxygenase-1, despite inhibition of nitric oxide production. In conclusion, nitric oxide deficiency upregulates hepatic heme oxygenase-1, which is reversible by maintaining hepatic blood flow. This interdependence has important implications for the development of therapeutic strategies aimed at modulating the activity of these hepatoprotective mediator systems.
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Affiliation(s)
- Alexander Hoetzel
- Department of Anesthesiology and Critical Care Medicine, University of Freiburg, Hugstetter Str. 55, D-79106 Freiburg, Germany.
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26
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Guerra GP, Mello CF, Sauzem PD, Berlese DB, Furian AF, Tabarelli Z, Rubin MA. Nitric oxide is involved in the memory facilitation induced by spermidine in rats. Psychopharmacology (Berl) 2006; 186:150-8. [PMID: 16601997 DOI: 10.1007/s00213-006-0376-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Accepted: 02/26/2006] [Indexed: 11/25/2022]
Abstract
RATIONALE Spermidine (SPD) is an endogenous polyamine that modulates N-methyl-D: -aspartate receptor functions, which has been reported to facilitate memory formation. OBJECTIVES In the current study, we investigated the involvement of nitric oxide in the facilitatory effect of SPD on the memory of adult male Wistar rats in the inhibitory avoidance task. RESULTS The coadministration of the nonspecific NOS inhibitor N (G) nitro-L: -arginine methyl ester (L: -NAME) (0.1 nmol, intrahippocampus) with spermidine (0.2 nmol), immediately after training, prevented the memory improvement caused by spermidine in the avoidance inhibitory task. Spermidine increased nitrite and nitrate levels (NO(X)) in the hippocampus 30 min after its administration, and L: -NAME coinjection prevented the stimulatory effect of spermidine on NO(X) levels. The systemic injection of 7-nitroindazole (30 mg/kg, i.p.), 30 min before training, impaired memory and did not prevent spermidine-induced increase of NO(X) levels in the hippocampus. CONCLUSIONS These results suggest that memory enhancement by spermidine is prevented by the nonspecific nitric oxide synthase inhibitor L: -NAME.
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Affiliation(s)
- Gustavo Petri Guerra
- Departamento de Química, Centro de Ciências Naturais e Exatas, Laboratório de Neurotoxicidade e Psicofarmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil,
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27
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Hink J, Thom SR, Simonsen U, Rubin I, Jansen E. Vascular reactivity and endothelial NOS activity in rat thoracic aorta during and after hyperbaric oxygen exposure. Am J Physiol Heart Circ Physiol 2006; 291:H1988-98. [PMID: 16648176 DOI: 10.1152/ajpheart.00145.2006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Accumulating evidence suggests that hyperbaric oxygen (HBO) stimulates neuronal nitric oxide (NO) synthase (NOS) activity, but the influence on endothelial NOS (eNOS) activity and vascular NO bioavailability remains unclear. We used a bioassay employing rat aortic rings to evaluate vascular NO bioavailability. HBO exposure to 2.8 atm absolute (ATA) in vitro decreased ACh relaxation. This effect remained unchanged, despite treatment with SOD-polyethylene glycol and catalase-polyethylene glycol, suggesting that the reduction in endothelium-derived NO bioavailability was independent of superoxide production. In vitro HBO induced contraction of resting aortic rings with and without endothelium, and these contractions were reduced by the NOS inhibitor N(omega)-nitro-l-arginine. In addition, in vitro HBO attenuated the vascular contraction produced by norepinephrine, and this effect was reversed by N(omega)-nitro-l-arginine, but not by endothelial denudation. These findings indicate stimulation of extraendothelial NO production during HBO exposure. A radiochemical assay was used to assess NOS activity in rat aortic endothelial cells. Catalytic activity of eNOS in cell homogenates was not decreased by HBO, and in vivo HBO exposure to 2.8 ATA was without effect on eNOS activity and/or vascular NO bioavailability in vitro. We conclude that HBO reduces endothelium-derived NO bioavailability independent of superoxide production, and this effect seems to be unrelated to a decrease in eNOS catalytic activity. In addition, HBO increases the resting tone of rat aortic rings and attenuates the contractile response to norepinephrine by endothelium-independent mechanisms that involve extraendothelial NO production.
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Affiliation(s)
- Jonas Hink
- Hyperbaric Oxygen Treatment Unit (4092 Dept. of Anaesthesia, The Centre of Head and Orthopaedics, Copenhagen Univ. Hospital Rigshospitalet, 9 Blegdamsvej, DK 2100 Copenhagen OE, Denmark.
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28
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Roszer T, Kiss-Tóth E, Petkó M, Szentmiklósi AJ, Bánfalvi G. Phe-met-arg-phe (FMRF)-amide is a substrate source of NO synthase in the gastropod nervous system. Cell Tissue Res 2006; 325:567-75. [PMID: 16612629 DOI: 10.1007/s00441-006-0185-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 02/01/2006] [Indexed: 12/18/2022]
Abstract
The possible involvement of the L-arginine-containing Phe-met-arg-phe (FMRF)-amide (FMRFa) in neuronal nitric oxide (NO) biosynthesis was studied in a gastropod species. We found NADPH-diaphorase-positive neurons and FMRFa-containing fibers in close proximity in the enteric nervous system. Administration of L-arginine and FMRFa induced quantitatively similar nitrite production in both intact intestinal tissues and tissue homogenates. These changes could be prevented by the presence of NOARG (an NO synthase inhibitor). Neither chemically modified FMRFa (D-arginine instead of L-arginine) nor amino acid constituents of FMRFa (methionine, phenylalanine) affected basal nitrite production. FMRFa-induced alterations were reduced in the presence of Na+ channel blockers (tetrodotoxin, amiloride, lidocaine), the Na+/K+ATPase inhibitor ouabain, or protease inhibitors (leupeptine, pepstatine-a). FMRFa and its amino acid constituents were analyzed by paper chromatography. When FMRFa was added to tissue homogenates, the peptide was eliminated within 1-2 min, whereas methionine, phenylalanine, arginine, and citrulline levels were elevated simultaneously. We tested the effects of FMRFa, L-arginine, and NOARG on intestinal contractile activity. FMRFa relaxed the intestine for 1-2 min and then induced contractions for 20-40 min. In the presence of NOARG, no relaxant effect of FMRFa was recorded. As administration of L-arginine strongly inhibits the mechanical activity of the intestinal muscle, NO production presumably plays a substantial role in the action of FMRFa, at least in the initial phase. Our biochemical data indicate a direct involvement of FMRFa in NO biosynthesis. FMRFa might be hydrolyzed by extracellular peptidases and then the locally released arginine might be transported into the cells and broken-down to produce NO. Depolarization-induced NO production attributable to the activation of amiloride-sensitive Na+ channels might also be involved.
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Affiliation(s)
- Tamás Roszer
- Department of Animal Anatomy & Physiology, Faculty of Science, Debrecen University, P.O. Box 15, H-4010 Debrecen, Hungary
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29
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Lefebvre RA, Dick JMC, Guérin S, Malbert CH. Influence of the selective neuronal NO synthase inhibitor ARL 17477 on nitrergic neurotransmission in porcine stomach. Eur J Pharmacol 2005; 525:143-9. [PMID: 16257402 DOI: 10.1016/j.ejphar.2005.09.053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Revised: 09/12/2005] [Accepted: 09/27/2005] [Indexed: 10/25/2022]
Abstract
Selective neuronal NOS (nNOS) inhibitors have been developed for possible application in cerebral ischemia and neurodegenerative disorders. To investigate the degree of interference with peripheral nNOS, the influence of the selective nNOS inhibitor ARL 17477 was studied on electrically induced nitrergic relaxations in pig gastric fundus strips and on gastric fundic compliance in conscious pig. Circular muscle strips of porcine gastric fundus were electrically stimulated (10 s trains at 4 Hz, 0.1 ms and 40 V). ARL 17477 inhibited the electrically induced relaxations in a concentration-dependent way (3x10(-6) M-10(-4) M). The inhibitory effect of ARL 17477 developed more progressively than that of N(G)-nitro-L-arginine methyl ester (L-NAME; 3x10(-4) M). In conscious pigs, instrumented with a fundic cannula, L-NAME (20 mg/kg i.v.) significantly increased mean arterial blood pressure and decreased fundic compliance in the fasted state (71+/-13 ml/mm Hg versus 185+/-37 ml/mm Hg after saline; P<0.05). ARL 17477 (3 mg/kg, i.v.) did not influence blood pressure but influenced gastric fundic volume-pressure curves in a similar way as L-NAME. Plasma concentration analysis of ARL 17477 indicated a half-life of less than 30 min in pig. ARL 17477 thus inhibits the effect of nitrergic neurons in the pig gastric fundus in vitro, leading to inhibited gastric compliance in the conscious pig. The study indicates that selective nNOS inhibitors, applied for cerebral disorders, might also interfere with neuronal nitrergic regulation of gastrointestinal motility.
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Affiliation(s)
- Romain A Lefebvre
- Heymans Institute of Pharmacology, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, B-9000 Gent, Belgium.
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McNeill B, Perry SF. Nitric oxide and the control of catecholamine secretion in rainbow trout Oncorhynchus mykiss. ACTA ACUST UNITED AC 2005; 208:2421-31. [PMID: 15939781 DOI: 10.1242/jeb.01636] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An in situ saline-perfused posterior cardinal vein preparation was used to assess the role of nitric oxide (NO) in the regulation of basal and stimulus-evoked catecholamine secretion from rainbow trout Oncorhynchus mykiss chromaffin cells. Addition of the NO donor, sodium nitroprusside (SNP) to the inflowing perfusate abolished catecholamine secretion during electrical field stimulation, thereby establishing the potential for NO to act as a potent inhibitor of catecholamine release. A possible role for endogenously produced NO was established by demonstrating that stimulus-evoked (depolarizing levels of KCl or electrical field stimulation) catecholamine secretion was markedly stimulated in the presence of the nitric oxide synthase (NOS) inhibitors l-NAME and 7-NI. Although in vitro experiments demonstrated that catecholamine degradation was enhanced by NO in a dose-dependent manner, the dominant factor contributing to the reduction in catecholamine appearance in the perfusate was specific inhibition of catecholamine secretion. Subsequent experiments were performed to identify the NOS isoform(s) contributing to the inhibition of stimulus-evoked catecholamine secretion. Inducible NOS (iNOS; an enzyme that can be activated in the absence of Ca2+), although present in the vicinity of the chromaffin cells (based on mRNA measurements), does not appear to play a role because stimulus-evoked NO production was eliminated during perfusion with Ca2+-free saline. The potential involvement of endothelial NOS (eNOS) was revealed by showing that hypoxic perfusate evoked NO production and corresponded with an inhibition of stimulus-evoked catecholamine secretion; chemical removal of the endothelium (using saponin) prevented the production of NO during hypoxia. However, because removal of the endothelium did not affect NO production during electrical field stimulation, it would appear that the neuronal form of NOS (nNOS) is the key isoform modulating catecholamine secretion from trout chromaffin cells.
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Affiliation(s)
- B McNeill
- Department of Biology, University of Ottawa, 10 Marie Curie, Ottawa, ON, Canada K1N 6N5
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31
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Mak S, Overgaard CB, Newton GE. Effect of vitamin C and L-NMMA on the inotropic response to dobutamine in patients with heart failure. Am J Physiol Heart Circ Physiol 2005; 289:H2424-8. [PMID: 16040714 DOI: 10.1152/ajpheart.00453.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The positive effect of vitamin C on left ventricular (LV) inotropic responses to dobutamine, observed in patients with preserved LV function, is lost in heart failure (HF). We tested the hypothesis that in HF, endogenous nitric oxide (NO) opposes the positive effect of vitamin C on adrenergically stimulated contractility by examining the effects of vitamin C on dobutamine responses during NO synthase inhibition. In 11 HF patients, a micromanometer-tipped catheter was inserted into the LV and an infusion catheter was positioned in the left main coronary artery. The peak positive rate of change of LV pressure (LV +dP/dt) was measured in response to intravenous dobutamine (Dob-1). After recontrol, intracoronary N(G)-monomethyl-L-arginine (l-NMMA) was infused before reinfusion of dobutamine (L-NMMA + Dob-2). Finally, intracoronary vitamin C was infused in addition to intracoronary L-NMMA and dobutamine (L-NMMA + Dob-2 + vitamin C). Intracoronary L-NMMA alone had no effect on LV +dP/dt. After a stable inotropic response to intracoronary L-NMMA and dobutamine was established, the addition of intracoronary vitamin C resulted in a modest but significant increase in LV +dP/dt. The change in LV +dP/dt in response to dobutamine alone was 25 +/- 5%, with intracoronary L-NMMA, 27 +/- 6%, and with intracoronary L-NMMA plus vitamin C, 37 +/- 5% (P < 0.05 vs. Dob-1 and L-NMMA + Dob-2). These findings demonstrate that an interaction between endogenous NO and redox environment exists and exerts some influence on stimulated contractility in HF.
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Affiliation(s)
- Susanna Mak
- Cardiovascular Clinical Research Laboratory, Div. of Cardiology, Mount Sinai Hospital, 600 University Ave., Rm. 1543, Toronto, Ontario, Canada M5G 1X5
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The influence of lidocaine and beta-blockers on L-NAME-induced potentiation of the isolated rat hemidiaphragm contractility. ACTA VET-BEOGRAD 2005. [DOI: 10.2298/avb0504259s] [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] Open
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33
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Stojanovic R, Todorovic Z, Nesic Z, Vuckovic S, Prostran M. Aminophylline Pretreatment Modulates the Nitric Oxide System of the Isolated Rat Diaphragm: the Role of Frequency of the Electrical Stimulation. J Pharmacol Sci 2005; 99:109-12. [PMID: 16141636 DOI: 10.1254/jphs.sce05002x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The effect of different frequencies of direct subtetanic electrical stimulation (14, 20, and 30 Hz) and aminophylline (AMPh) pretreatment on the effect of N(G)-nitro-L-arginine methyl ester (L-NAME) (1 mM) on isolated rat diaphragm was investigated. L-NAME potentiated tension developed (Td) in the diaphragm pretreated with a single concentration of AMPh (1.08 mM) in a frequency-dependent manner. The effect was significantly different in comparison with muscle incubated 30 min with Tyrode solution only. In the muscle pretreated with cumulative concentrations of AMPh (0.36 - 3.60 mM), the frequency-dependent potentiation of Td induced by L-NAME and the difference between L-NAME-treated and untreated muscle were lost.
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Affiliation(s)
- Radan Stojanovic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, School of Medicine University of Belgrade, Serbia
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Bauer C, Kuntz W, Ohnsmann F, Gasser H, Weber C, Redl H, Marzi I. The attenuation of hepatic microcirculatory alterations by exogenous substitution of nitric oxide by s-nitroso-human albumin after hemorrhagic shock in the rat. Shock 2004; 21:165-9. [PMID: 14752291 DOI: 10.1097/01.shk.0000107442.26299.fb] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Hepatic microcirculatory disorders such as narrowing of sinusoids after hemorrhagic shock play a major role in the pathogenesis of organ failure. It is known that the balance of vasoactive mediators such as endothelin and nitric oxide (NO) regulate microvascular perfusion, including the diameter of hepatic sinusoids. The present study was designed to evaluate the role of exogenous substitution of NO by S-nitroso-albumin (S-NO-HSA) in the prevention of pathophysiological alterations of hepatic microcirculation. Anesthetized Sprague-Dawley rats were instrumented for invasive hemodynamic monitoring. Hemorrhagic shock was induced by bleeding to a mean arterial pressure (MAP) of 40 mmHg and was maintained for 60 min. Thereafter, the animals were resuscitated with shed blood and Ringer's solution. During the first hour of resuscitation, S-NO-HSA or pure HSA was infused continuously (10 micromol/kg/h) and hepatic microcirculation was detected by intravital epifluorescence microscopy either 5 or 24 h after the insult. Results were compared with a sham-treated group (n = 6-8 per group). Shock-induced microcirculatory narrowing of sinusoids was significantly reduced in the S-NO-HSA group compared with the HSA group both at 5 and 24 h (HSA: 9.3 +/- 0.2 microm; S-NO-HSA: 12.1 +/- 0.2 microm, P < 0.05). Sinusoidal perfusion was significantly higher in the S-NO-HSA group than in the HSA group (HSA: 50,934 +/- 1,382 microm3/s; S-NO-HSA: 78,120 +/- 2,348 microm3/s, P < 0.05). Reversible leukocyte adhesion to sinusoidal endothelium, an indicator of the inflammatory response, was significantly reduced in the S-NO-HAS-treated group. The findings of this study in a rat model of hemorrhagic shock suggest that NO substitution by S-NO-HSA during resuscitation attenuates both early and late hepatic microcirculatory disturbances as well as the increase in leukocyte adherence.
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Affiliation(s)
- Clemens Bauer
- Departments of Trauma Surgery and Anesthesiology, University of Saarland, Homburg/Saar, Germany
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Tiyyagura SR, Kazerounian S, Schulz S, Waldman SA, Pitari GM. Reciprocal regulation and integration of signaling by intracellular calcium and cyclic GMP. VITAMINS AND HORMONES 2004; 69:69-94. [PMID: 15196879 DOI: 10.1016/s0083-6729(04)69003-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Calcium and guanosine-3',5'-cyclic monophosphate (cGMP) are second messenger molecules that regulate opposing physiological functions, reflected in the reciprocal regulation of their intracellular concentrations, in many systems. Indeed, cGMP and Ca2+ constitute discrete points of integration between multiple cell signaling cascades in both convergent and parallel pathways. This chapter describes the molecular mechanisms regulating intracellular Ca2+ and cGMP, and their integration in specific cellular responses.
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Affiliation(s)
- Satish R Tiyyagura
- Division of Clinical Pharmacology, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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Li D, Stuehr DJ, Yeh SR, Rousseau DL. Heme distortion modulated by ligand-protein interactions in inducible nitric-oxide synthase. J Biol Chem 2004; 279:26489-99. [PMID: 15066989 DOI: 10.1074/jbc.m400968200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The catalytic center of nitric-oxide synthase (NOS) consists of a thiolate-coordinated heme macrocycle, a tetrahydrobiopterin (H4B) cofactor, and an l-arginine (l-Arg)/N-hydroxyarginine substrate binding site. To determine how the interplay between the cofactor, the substrates, and the protein matrix housing the heme regulates the enzymatic activity of NOS, the CO-, NO-, and CN(-)-bound adducts of the oxygenase domain of the inducible isoform of NOS (iNOS(oxy)) were examined with resonance Raman spectroscopy. The Raman data of the CO-bound ferrous protein demonstrated that the presence of l-Arg causes the Fe-C-O moiety to adopt a bent structure because of an H-bonding interaction whereas H4B binding exerts no effect. Similar behavior was found in the CN(-)-bound ferric protein and in the nitric oxide (NO)-bound ferrous protein. In contrast, in the NO-bound ferric complexes, the addition of l-Arg alone does not affect the structural properties of the Fe-N-O moiety, but H4B binding forces it to adopt a bent structure, which is further enhanced by the subsequent addition of l-Arg. The differential interactions between the various heme ligands and the protein matrix in response to l-Arg and/or H4B binding is coupled to heme distortions, as reflected by the development of a variety of out-of-plane heme modes in the low frequency Raman spectra. The extent and symmetry of heme deformation modulated by ligand, substrate, and cofactor binding may provide important control over the catalytic and autoinhibitory properties of the enzyme.
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Affiliation(s)
- David Li
- Department of Physiology and Biophysics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York 10461, USA
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Mak S, Newton GE. Redox modulation of the inotropic response to dobutamine is impaired in patients with heart failure. Am J Physiol Heart Circ Physiol 2003; 286:H789-95. [PMID: 14551049 DOI: 10.1152/ajpheart.00633.2003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been suggested that oxidative stress contributes to impaired left ventricular (LV) contractility in the setting of heart failure (HF). To test this hypothesis, we studied the effect of an antioxidant on contractility at rest and in response to dobutamine in 10 HF patients. We hypothesized that vitamin C would augment contractility in HF and that this effect would be of a greater magnitude in HF patients compared with patients with normal LV (NLV) function. Data from 10 patients with NLV function who participated in this study are included in this report and have been published elsewhere. A micromanometer-tipped catheter was introduced into the LV. In the experimental protocol, an infusion catheter was positioned in the left main coronary artery. The peak positive rate of change of LV pressure (LV +dP/dt) was measured in response to the intravenous infusion of dobutamine before and during the intracoronary infusion of vitamin C (96 mg/min). Vitamin C had no effect on basal LV +dP/dt in either HF or NLV groups. The infusion of vitamin C augmented the LV +dP/dt response to dobutamine by 22 +/- 4% in the NLV function group. In contrast, vitamin C had no effect on the inotropic response to dobutamine in the HF group. In the control protocol, without vitamin C, no differences were observed between responses to two sequential dobutamine infusions in either group (HF, n = 11; NLV, n = 9). Therefore, a positive effect of vitamin C on contractility was limited to patients with NLV function. The absence of this effect in HF patients may suggest that normal redox responsiveness is lost in this disease state.
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Affiliation(s)
- Susanna Mak
- Bayer Cardiovascular Clinical Research Laboratory, Division of Cardiology, Mount Sinai Hospital, University of Toronto, Ontario, Canada
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DeWitt DS, Prough DS. Traumatic Cerebral Vascular Injury: The Effects of Concussive Brain Injury on the Cerebral Vasculature. J Neurotrauma 2003; 20:795-825. [PMID: 14577860 DOI: 10.1089/089771503322385755] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In terms of human suffering, medical expenses, and lost productivity, head injury is one of the major health care problems in the United States, and inadequate cerebral blood flow is an important contributor to mortality and morbidity after traumatic brain injury. Despite the importance of cerebral vascular dysfunction in the pathophysiology of traumatic brain injury, the effects of trauma on the cerebral circulation have been less well studied than the effects of trauma on the brain. Recent research has led to a better understanding of the physiologic, cellular, and molecular components and causes of traumatic cerebral vascular injury. A more thorough understanding of the direct and indirect effects of trauma on the cerebral vasculature will lead to improvements in current treatments of brain trauma as well as to the development of novel and, hopefully, more effective therapeutic strategies.
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Affiliation(s)
- Douglas S DeWitt
- Charles R. Allen Research Laboratories, Department of Anesthesiology, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-0830, USA.
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Lin Z, Chen S, Ye C, Zhu S. Nitric oxide synthase expression in human bladder cancer and its relation to angiogenesis. UROLOGICAL RESEARCH 2003; 31:232-5. [PMID: 12937869 DOI: 10.1007/s00240-003-0302-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2001] [Accepted: 01/08/2003] [Indexed: 01/22/2023]
Abstract
Nitric oxide (NO) is synthesized by the enzyme family of nitric oxide synthases (NOS) and plays an important role in tumor growth and angiogenesis. The expression of two of the NOS isoforms, the endothelial and inducible isoforms (eNOS and iNOS, respectively), were evaluated in bladder tissue from patients with transitional cell carcinoma (TCC). The specimens were procured from 58 patients with TCC and 14 cases of normal bladder mucosa were used as a control group. NOS immunohistochemistry was performed and microvessal density (MVD) was determined. iNOS specific proteins were found in 47 of 58 bladder cancer specimens but not in control bladder tissue. The endothelial cells in both normal urothelium and tumor tissue showed a highly positive eNOS immunostaining. The MVD was 39.3+/-19.5 and 29.3+/-10.5 in TCC positive and negative for iNOS, respectively ( P<0.01). A correlation between iNOS immunoreactivity and tumor grade in bladder carcinoma could not be verified. These results indicate that NO generation from iNOS in the malignant epithelium and from eNOS in tumor stroma play a important role in tumor angiogenesis.
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Affiliation(s)
- Zhen Lin
- Department of Urology, Union Hospital Affiliated to Fujian Medical University, Fuzhou 350001, People's Republic of China.
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40
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Habisch HJ, Gorren ACF, Liang H, Venema RC, Parkinson JF, Schmidt K, Mayer B. Pharmacological interference with dimerization of human neuronal nitric-oxide synthase expressed in adenovirus-infected DLD-1 cells. Mol Pharmacol 2003; 63:682-9. [PMID: 12606778 DOI: 10.1124/mol.63.3.682] [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: 11/22/2022] Open
Abstract
A recombinant adenovirus containing the cDNA of human neuronal nitric-oxide synthase (nNOS) was constructed to characterize the interaction of nNOS with N-[(1,3-benzodioxol-5-yl)methyl]-1-[2-(1H-imidazole-1-yl)pyrimidin-4-yl]-4-(methoxycarbonyl)-piperazine-2-acetamide (BBS-1), a potent inhibitor of inducible NOS dimerization [Proc Natl Acad Sci USA 97:1506-1511, 2000]. BBS-1 inhibited de novo expression of nNOS activity in virus-infected cells at a half-maximal concentration (IC(50)) of 40 +/- 10 nM in a reversible manner. Low-temperature gel electrophoresis showed that BBS-1 attenuated the formation of SDS-resistant nNOS dimers with an IC(50) of 22 +/- 5.2 nM. Enzyme inhibition progressively decreased with increasing time of addition after infection. BBS-1 did not significantly inhibit dimeric nNOS activity (IC(50) > 1 mM). Long-term incubation with BBS-1 of human embryonic kidney cells stably transfected with nNOS or endothelial NOS revealed a slow time- and concentration-dependent decrease of NOS activity with half-lives of 30 and 43 h and IC(50) values of 210 +/- 30 nM and 12 +/- 0.5 microM, respectively. These results establish that BBS-1 interferes with the assembly of active nNOS dimers during protein expression. Slow inactivation of constitutively expressed NOS in intact cells may reflect protein degradation and interference of BBS-1 with the de novo synthesis of functionally active NOS dimers. As time-dependent inhibitors of NOS dimerization, BBS-1 and related compounds provide a promising strategy to develop a new class of selective and clinically useful NOS inhibitors.
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Affiliation(s)
- Hans-Jörg Habisch
- Institut für Pharmakologie und Toxikologie, Karl-Franzens-Universität Graz, Graz, Austria
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41
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Skidgel RA, Gao XP, Brovkovych V, Rahman A, Jho D, Predescu S, Standiford TJ, Malik AB. Nitric oxide stimulates macrophage inflammatory protein-2 expression in sepsis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:2093-101. [PMID: 12165537 DOI: 10.4049/jimmunol.169.4.2093] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
NO is a crucial mediator of the inflammatory response, but its in vivo role as a determinant of lung inflammation remains unclear. We addressed the in vivo role of NO in regulating the activation of NF-kappaB and expression of inflammatory proteins using an in vivo mouse model of sepsis induced by i.p. injection of Escherichia coli. We observed time-dependent degradation of IkappaB and activation of NF-kappaB accompanied by increases in inducible NOS, macrophage inflammatory protein-2 (MIP-2), and ICAM-1 expression after E. coli challenge, which paralleled the ability of lung tissue to produce high-output NO. To determine the role of NO in this process, mice were pretreated with the NO synthase (NOS) inhibitor NG-methyl-L-arginine. Despite having relatively modest effects on NF-kappaB activation and ICAM-1 or inducible NOS expression, the NOS inhibitor almost completely inhibited expression of MIP-2 in response to E. coli challenge. These responses were associated with the inhibition of migration of neutrophils in lung tissue and increased permeability induced by E. coli. In mice pretreated with NG-methyl-L-arginine, coadministration of E. coli with the NO donor (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate substantially restored MIP-2 expression but decreased ICAM-1 expression. The results suggest that NO generated after administration of E. coli serves as an important proinflammatory signal to up-regulate MIP-2 expression in vivo. Thus, NO production in high quantities may be important in the mechanism of amplification of the lung inflammatory response associated with sepsis.
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Affiliation(s)
- Randal A Skidgel
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, USA.
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Coruzzi G, Coppelli G, Spaggiari S, Cavestro GM, Okolicsanyi L, Lo Giudice P, Pisano C, Tepperman BL. Gastroprotective effects of amtolmetin guacyl: a new non-steroidal anti-inflammatory drug that activates inducible gastric nitric oxide synthase. Dig Liver Dis 2002; 34:403-10. [PMID: 12132787 DOI: 10.1016/s1590-8658(02)80037-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND The novel non-steroidal anti-inflammatory drug amtolmetin guacyl has been shown to possess markedly reduced ulcerogenic effects and nitric oxide-mediated gastroprotective activity against the damage induced by ethanol in the rat. AIMS To investigate, in the rat, the role of nitric oxide and of inducible nitric oxide synthase isoform in the protective effect of amtolmetin guacyl against the gastric damage induced by ethanol. METHODS The effects of amtolmetin guacyl on gastric transmucosal potential difference and on gastric mucosal blood flow were investigated in the anaesthetised rat; myeloperoxidase activity, inducible and endothelial nitric oxide synthase protein content were determined in rat gastric mucosal homogenates. The anti-inflammatory drug tolmetin and the bacterial lipopolysaccharide from Escherichia coli were studied for comparison. RESULTS In the anaesthetised rat, amtolmetin guacyl, but not tolmetin, reduced by approximately 50% the fall in gastric potential difference and, to a lesser extent, the macroscopic damage induced by ethanol. The effect of amtolmetin guacyl on transmucosal potential difference was prevented by the selective inducible nitric oxide synthase inhibitor 1400W. In amtolmetin guacyl-treated rats, 1400W decreased gastric mucosal blood flow, whereas it was inactive in vehicle- and tolmetin-treated animals. In gastric mucosal homogenates, both amtolmetin guacyl and lipopolysaccharide, but not tolmetin, increased inducible, but not endothelial, nitric oxide synthase protein content, as revealed by Western immunoblotting. CONCLUSIONS These data confirm that amtolmetin guacyl is a non-steroidal anti-inflammatory agent devoid of gastrolesive properties, that can actually reduce the damaging effects of ethanol through the increase in nitric oxide production, via the inducible isoform of nitric oxide synthase.
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Affiliation(s)
- G Coruzzi
- Institute of Pharmacology, School of Medicine, University of Parma, Italy.
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Mak S, Egri Z, Tanna G, Colman R, Newton GE. Vitamin C prevents hyperoxia-mediated vasoconstriction and impairment of endothelium-dependent vasodilation. Am J Physiol Heart Circ Physiol 2002; 282:H2414-21. [PMID: 12003853 DOI: 10.1152/ajpheart.00947.2001] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
High arterial blood oxygen tension increases vascular resistance, possibly related to an interaction between reactive oxygen species and endothelium-derived vasoactive factors. Vitamin C is a potent antioxidant capable of reversing endothelial dysfunction due to increased oxidant stress. We tested the hypotheses that hyperoxic vasoconstriction would be prevented by vitamin C, and that acetylcholine-mediated vasodilation would be blunted by hyperoxia and restored by vitamin C. Venous occlusion strain gauge plethysmography was used to measure forearm blood flow (FBF) in 11 healthy subjects and 15 congestive heart failure (CHF) patients, a population characterized by endothelial dysfunction and oxidative stress. The effect of hyperoxia on FBF and derived forearm vascular resistance (FVR) at rest and in response to intra-arterial acetylcholine was recorded. In both healthy subjects and CHF patients, hyperoxia-mediated increases in basal FVR were prevented by the coinfusion of vitamin C. In healthy subjects, hyperoxia impaired the acetylcholine-mediated increase in FBF, an effect also prevented by vitamin C. In contrast, hyperoxia had no effect on verapamil-mediated increases in FBF. In CHF patients, hyperoxia did not affect FBF responses to acetylcholine or verapamil. The addition of vitamin C during hyperoxia augmented FBF responses to acetylcholine. These results suggest that hyperoxic vasoconstriction is mediated by oxidative stress. Moreover, hyperoxia impairs acetylcholine-mediated vasodilation in the setting of intact endothelial function. These effects of hyperoxia are prevented by vitamin C, providing evidence that hyperoxia-derived free radicals impair the activity of endothelium-derived vasoactive factors.
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Affiliation(s)
- Susanna Mak
- Cardiovascular Division, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, M5G 1X5 Canada
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Mosi R, Seguin B, Cameron B, Amankwa L, Darkes MC, Fricker SP. Mechanistic studies on AMD6221: a ruthenium-based nitric oxide scavenger. Biochem Biophys Res Commun 2002; 292:519-29. [PMID: 11906192 DOI: 10.1006/bbrc.2002.6685] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide is a mediator of many disease states. Previous studies have demonstrated that ruthenium(III) polyaminocarboxylates can react with NO to form stable complexes reducing the levels of nitrite in the culture medium of stimulated RAW264 macrophages and reverse the NO-mediated hypotension in animal models of septic shock. It was necessary to confirm that these observations were due to NO scavenging and not inhibition of the NO metabolic pathway. Using RAW264 cells it was confirmed that [Ru(H(3)dtpa)(Cl)] (AMD6221) was neither acting at the level of iNOS induction, nor as an inhibitor of iNOS by measuring iNOS mRNA by RT-PCR and protein by Western blot and enzyme activity. Using HPLC, the nitrosyl adduct of reaction of AMD6221, [Ru(H(2)dtpa)NO], was identified in the medium of stimulated RAW264 cells co-incubated with AMD6221, concomitant with a stoichiometric reduction in nitrite/nitrate levels, thus confirming that the ruthenium(III) polyaminocarboxylates exert their pharmacological effect by scavenging NO.
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Affiliation(s)
- R Mosi
- AnorMED Inc., 200-20353 64th Avenue, Langley, British Columbia, Canada
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Benito S, Lopez D, Sáiz MP, Buxaderas S, Sánchez J, Puig-Parellada P, Mitjavila MT. A flavonoid-rich diet increases nitric oxide production in rat aorta. Br J Pharmacol 2002; 135:910-6. [PMID: 11861318 PMCID: PMC1573198 DOI: 10.1038/sj.bjp.0704534] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Red wine intake is associated with a low risk of cardiovascular disease. This effect has been partly attributed to the action of polyphenolic compounds, which decrease the oxidation of plasma low density lipoproteins. Moreover, nitric oxide ((*)NO) is a vasodilator and polyphenolic compounds induce endothelium-dependent vasorelaxation in vitro. 2. Here we studied whether a diet rich in dealcoholated red wine (DRW) increases acetylcholine-induced vasorelaxation and whether ingestion of DRW-, quercetin- or catechin-rich diets modifies the (*)NO-cyclic guanosine-3',5'-monophosphate (cyclic GMP) pathway and superoxide anion (O2(.-)) release in aorta in a resting state in rats fed semi-purified diets containing either 35% (v w(-1)) DRW, 0.3% (w w(-1)) quercetin or 0.3% (w w(-1)) catechin for 10 days. 3. (*)NO-mediated vasorelaxation induced by acetylcholine was greater in rats fed the DRW-rich diet than in those that received the control diet. 4. Expression of endothelial (*)NO synthase (eNOS) was similar in the four dietary groups. The aortic rings of rats fed either the DRW-, quercetin-, or catechin-rich diets showed higher NOS activity, (*)NO production and cyclic GMP content than those of rats fed the control diet. No changes were observed in O2(.-) production. 5. In summary, diets rich in either DRW, quercetin or catechin induced endothelium-dependent vasorelaxation in rat aorta in a resting state through the enhancement of (*)NO production, without modifying O2(.-) generation, thus the bioavailability of (*)NO was increased. The increase in the (*)NO-cyclic GMP pathway explains the beneficial effect of flavonoids at vascular level.
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Affiliation(s)
- S Benito
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Departament de Nutrició i Bromatologia (CERNCA), Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - D Lopez
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - M P Sáiz
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - S Buxaderas
- Departament de Nutrició i Bromatologia (CERNCA), Facultat de Farmàcia, Universitat de Barcelona, Barcelona, Spain
| | - J Sánchez
- Departament de Farmacologia, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - P Puig-Parellada
- Departament de Farmacologia, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - M T Mitjavila
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Author for correspondence:
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Miyata T, Devuyst O, Kurokawa K, van Ypersele de Strihou C. Toward better dialysis compatibility: advances in the biochemistry and pathophysiology of the peritoneal membranes. Kidney Int 2002; 61:375-86. [PMID: 11849377 DOI: 10.1046/j.1523-1755.2002.00135.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Peritoneal dialysis (PD) has modified our concept of the peritoneal membrane, which is now a topic of active research. Peritoneal solute transport progressively increases with time on PD, enhances the dissipation of the osmotic gradient and, eventually, reduces ultrafiltration capacity. The causes of peritoneal membrane failure remain elusive. Recurrent episodes of peritonitis are not a prerequisite for the development of ultrafiltration failure. Functionally, the changes of the failing peritoneal membrane are best described as an increased functional area of exchange for small solutes between blood and dialysate. Histologically, these events are associated with vascular proliferation and structural changes of pre-existing vessels. Gathered evidence, including information on the composition of peritoneal cavity fluids and its dependence on the uremic environment, have cast a new light on the molecular mechanisms of decline in peritoneal membrane function. Chronic uremia per se modifies the peritoneal membrane and increases the functional area of exchange for small solutes. Biochemical alterations in the peritoneum inherent to uremia might be, at least in part, accounted for by severe reactive carbonyl compounds overload originating both from uremic circulation and PD fluid ("peritoneal carbonyl stress"). The molecular events associated with long-term PD are similar but more severe than those present in chronic uremia without PD, including modifications of nitric oxide synthase (NOS) and angiogenic growth factors expression, and advanced glycation and lipoxidation of the peritoneal proteins. This review focuses on reactive carbonyls and their association with a number of molecular changes observed in peritoneal tissues. This hypothetical approach will require further testing. Nevertheless, the insights gained on the peritoneal membrane offer a new paradigm to assess the effect of uremic toxins on serosal membranes. Furthermore, the progresses made in the dissection of the molecular events leading to peritoneal membrane failure open new avenues to develop safe, more biocompatible peritoneal dialysis technologies.
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Affiliation(s)
- Toshio Miyata
- Molecular and Cellular Nephrology, Institute of Medical Sciences and Department of Internal Medicine, Tokai University School of Medicine, Isehara, Japan.
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Gori T, Mak SS, Kelly S, Parker JD. Evidence supporting abnormalities in nitric oxide synthase function induced by nitroglycerin in humans. J Am Coll Cardiol 2001; 38:1096-101. [PMID: 11583888 DOI: 10.1016/s0735-1097(01)01510-8] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVES We studied the effects of nitroglycerin (GTN) therapy on the response to endothelium-dependent and independent vasoactive agents in the forearm circulation of healthy subjects. BACKGROUND Recent evidence suggests that therapy with GTN may induce specific changes in endothelial cell function, including increased superoxide anion production and sensitivity to vasoconstrictors. Additionally, continuous GTN therapy worsens endothelial function in the coronary circulation of patients with ischemic heart disease. METHODS Forearm blood flow was measured with venous occlusion, mercury-in-silastic strain gauge plethysmography. RESULTS Sixteen male volunteers (26 +/- 6 years) were randomized to no therapy (control) or GTN, 0.6 mg/h/24 h, for six days in an investigator-blind, parallel-design study. The flow responses to brachial artery infusions of acetylcholine ([Ach] 7.5, 15.0, 30.0 microg/min), N-monomethyl-L-arginine (L-NMMA) (1, 2, 4 micromol/min) and sodium nitroprusside (SNP) (0.8, 1.6, 3.2 microg/min) were recorded. The vasodilator responses to Ach were blunted in the GTN group as compared with the control group (p < 0.05). The vasoconstrictor responses to L-NMMA were also blunted in the GTN group (p < 0.001). In the GTN group, paradoxical vasodilation was observed in response to the lowest infused concentration of L-NMMA. The vasodilator responses to SNP did not differ between groups. CONCLUSIONS The response to Ach confirms the hypothesis that continuous GTN causes endothelial dysfunction. The responses to L-NMMA suggest that GTN therapy causes abnormalities in nitric oxide synthase (NOS) function; the vasodilation observed at the lowest infused concentration of L-NMMA in the GTN group also suggests that continuous GTN therapy is associated with a NOS-mediated production of a vasoconstrictor.
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Affiliation(s)
- T Gori
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, Toronto, Canada
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Kostic TS, Andric SA, Stojilkovic SS. Spontaneous and receptor-controlled soluble guanylyl cyclase activity in anterior pituitary cells. Mol Endocrinol 2001; 15:1010-22. [PMID: 11376118 DOI: 10.1210/mend.15.6.0648] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Nitric oxide (NO)-dependent soluble guanylyl cyclase (sGC) is operative in mammalian cells, but its presence and the role in cGMP production in pituitary cells have been incompletely characterized. Here we show that sGC is expressed in pituitary tissue and dispersed cells, enriched lactotrophs and somatotrophs, and GH(3) immortalized cells, and that this enzyme is exclusively responsible for cGMP production in unstimulated cells. Basal sGC activity was partially dependent on voltage-gated calcium influx, and both calcium-sensitive NO synthases (NOS), neuronal and endothelial, were expressed in pituitary tissue and mixed cells, enriched lactotrophs and somatotrophs, and GH(3) cells. Calcium-independent inducible NOS was transiently expressed in cultured lactotrophs and somatotrophs after the dispersion of cells, but not in GH(3) cells and pituitary tissue. This enzyme participated in the control of basal sGC activity in cultured pituitary cells. The overexpression of inducible NOS by lipopolysaccharide + interferon-gamma further increased NO and cGMP levels, and the majority of de novo produced cGMP was rapidly released. Addition of an NO donor to perifused pituitary cells also led to a rapid cGMP release. Calcium-mobilizing agonists TRH and GnRH slightly increased basal cGMP production, but only when added in high concentrations. In contrast, adenylyl cyclase agonists GHRH and CRF induced a robust increase in cGMP production, with EC(50)s in the physiological concentration range. As in cells overexpressing inducible NOS, the stimulatory action of GHRH and CRF was preserved in cells bathed in calcium-deficient medium, but was not associated with a measurable increase in NO production. These results indicate that sGC is present in secretory anterior pituitary cells and is regulated in an NO-dependent manner through constitutively expressed neuronal and endothelial NOS and transiently expressed inducible NOS, as well as independently of NO by adenylyl cyclase coupled-receptors.
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Affiliation(s)
- T S Kostic
- Endocrinology and Reproduction Research Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
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Raman CS, Li H, Martásek P, Babu BR, Griffith OW, Masters BS, Poulos TL. Implications for isoform-selective inhibitor design derived from the binding mode of bulky isothioureas to the heme domain of endothelial nitric-oxide synthase. J Biol Chem 2001; 276:26486-91. [PMID: 11331290 DOI: 10.1074/jbc.m102255200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nitric oxide produced by nitric-oxide synthase (NOS) is not only involved in a wide range of physiological functions but also in a variety of pathological conditions. Isoform-selective NOS inhibitors are highly desirable to regulate the NO production of one isoform beneficial to normal physiological functions from the uncontrolled NO production of another isoform that accompanies certain pathological states. Crystal structures of the heme domain of the three NOS isoforms have revealed a very high degree of similarity in the immediate vicinity of the heme active site illustrating the challenge of isoform-selective inhibitor design. Isothioureas are potent NOS inhibitors, and the structures of the endothelial NOS heme domain complexed with isothioureas bearing small S-alkyl substituents have been determined (Li, H., Raman, C.S., Martásek, P., Král, V., Masters, B.S.S., and Poulos, T.L. (2000) J. Inorg. Biochem. 81, 133--139). In the present communication, the binding mode of larger bisisothioureas complexed to the endothelial NOS heme domain has been determined. These structures afford a structural rationale for the known inhibitory activities. In addition, these structures provide clues on how to exploit the longer inhibitor substituents that extend out of the active site pocket for isoform-selective inhibitor design.
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Affiliation(s)
- C S Raman
- Department of Molecular Biology & Biochemistry, University of California, Irvine, California 92697, USA
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López D, Caballero C, Sánchez J, Puig-Parellada P, Mitjavila MT. Free radical production in aortic rings from rats fed a fish oil-rich diet. Am J Physiol Heart Circ Physiol 2001; 280:H2929-35. [PMID: 11356654 DOI: 10.1152/ajpheart.2001.280.6.h2929] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
To study the effect of the degree of unsaturation of dietary fatty acids on the production of free radicals and on the vascular smooth muscle tone in rings of the aorta, Sprague-Dawley rats were fed a semipurified diet containing 5% lipids from either corn oil (CO) or menhaden oil (MO) for 8 wk. The MO diet did not change the basal or NADPH-dependent superoxide anion (O[Formula: see text]·) release. There were no significant differences in phenylephrine-induced contractions between the two groups in intact rings. However, these contractions increased in endothelium-intact aortic rings from the MO group after addition of the nitric oxide (·NO) synthase inhibitor N G-nitro-l-arginine and in endothelium-denuded rings, both indicating a greater endothelial basal ·NO production in rats fed with the MO diet. Endothelium-dependent relaxations in response to acetylcholine were more prominent in rings from the MO group. These differences were not due to an increased smooth muscle response to ·NO, because relaxations were the same using an exogenous ·NO donor. Our results indicate that dietary MO did not modify O[Formula: see text]· release by the vessel wall or relaxation due to the cyclooxygenase pathway, but it potentiated endothelial production of ·NO.
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Affiliation(s)
- D López
- Departament de Fisiologia, Facultat de Biologia, Universitat de Barcelona, E-08028 Barcelona, Spain
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