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Search Results: 1 - 10 of 59 matches for " Peroxynitrite "
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Nitric Oxide/Peroxynitrite Redox Imbalance in Endothelial Cells Measured with Amperometric Nanosensors  [PDF]
Andrzej Burewicz, Hazem Dawoud, Lu-Lin Jiang, Tadeusz Malinski
American Journal of Analytical Chemistry (AJAC) , 2013, DOI: 10.4236/ajac.2013.410A1004
Abstract:

The cytoprotective messenger nitric oxide (NO) and cytotoxic peroxynitrite (ONOO-) are the main components of oxidative stress and can be generated by endothelial cells. A tandem of electrochemical nanosensors (diameter 200-300 nm) were used to measure, in situ, the balance between NO and ONOO-produced by human umbilical vein endothelial cells (HUVEC’s). The amperometric nanosensors were placed 5 ± 2 μm from the surface of the endothelial cells and the concentration of NO and ONOO- was measured at 630 mV and -300 mV (vs Ag/AgCl) respectively. Normal, functional, endothelial cells produced maximal 450 ± 25 nmol.L-1 of NO and 180 ± 15 nmol.L-1 of ONOO- in about 3 s, after stimulation with calcium ionophore. The in situ measurements of NO and ONOO- were validated using nitric oxide synthase inhibitor L-NMMA, ONOO

Gelam Honey Scavenges Peroxynitrite During the Immune Response
Mustafa Kassim,Marzida Mansor,Anwar Suhaimi,Gracie Ong,Kamaruddin Mohd Yusoff
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms130912113
Abstract: Monocytes and macrophages are part of the first-line defense against bacterial, fungal, and viral infections during host immune responses; they express high levels of proinflammatory cytokines and cytotoxic molecules, including nitric oxide, reactive oxygen species, and their reaction product peroxynitrite. Peroxynitrite is a short-lived oxidant and a potent inducer of cell death. Honey, in addition to its well-known sweetening properties, is a natural antioxidant that has been used since ancient times in traditional medicine. We examined the ability of Gelam honey, derived from the Gelam tree ( Melaleuca spp.), to scavenge peroxynitrite during immune responses mounted in the murine macrophage cell line RAW 264.7 when stimulated with lipopolysaccharide/interferon-γ (LPS/IFN-γ) and in LPS-treated rats. Gelam honey significantly improved the viability of LPS/IFN-γ-treated RAW 264.7 cells and inhibited nitric oxide production—similar to the effects observed with an inhibitor of inducible nitric oxide synthase (1400W). Furthermore, honey, but not 1400W, inhibited peroxynitrite production from the synthetic substrate 3-morpholinosydnonimine (SIN-1) and prevented the peroxynitrite-mediated conversion of dihydrorhodamine 123 to its fluorescent oxidation product rhodamine 123. Honey inhibited peroxynitrite synthesis in LPS-treated rats. Thus, honey may attenuate inflammatory responses that lead to cell damage and death, suggesting its therapeutic uses for several inflammatory disorders.
Ghost protein damage by peroxynitrite and its protection by melatonin
Di Mascio, P.;Dewez, B.;Garcia, C.R.S.;
Brazilian Journal of Medical and Biological Research , 2000, DOI: 10.1590/S0100-879X2000000100002
Abstract: we have studied the effect of peroxynitrite (onoo-) on the membrane cytoskeleton of red blood cells and its protection by melatonin. analysis of the protein fraction of the preparation by sds-page revealed a dose-dependent (0-600 μm onoo-) disappearance at ph 7.4 of the main proteins: spectrin, band 3, and actin, with the concomitant formation of high-molecular weight aggregates resistant to reduction by ?-mercaptoethanol (2%) at room temperature for 20 min. these aggregates were not solubilized by 8 m urea. incubation of the membrane cytoskeleton with onoo- was characterized by a marked depletion of free sulfhydryl groups (50% at 250 μm onoo-). however, a lack of effect of ?-mercaptoethanol suggests that, under our conditions, aggregate formation is not mediated only by sulfhydryl oxidation. the lack of a protective effect of the metal chelator diethylenetriaminepentaacetic acid confirmed that onoo--induced oxidative damage does not occur only by a transition metal-dependent mechanism. however, we demonstrated a strong protection against cytoskeletal alterations by desferrioxamine, which has been described as a direct scavenger of the protonated form of peroxynitrite. desferrioxamine (0.5 mm) also inhibited the loss of tryptophan fluorescence observed when the ghosts were treated with onoo-. glutathione, cysteine, and trolox? (1 mm), but not mannitol (100 mm), were able to protect the proteins against the effect of onoo- in a dose-dependent manner. melatonin (0-1 mm) was especially efficient in reducing the loss of spectrin proteins when treated with onoo- (90% at 500 μm melatonin). our findings show that the cytoskeleton, and in particular spectrin, is a sensitive target for onoo-. specific antioxidants can protect against such alterations, which could seriously impair cell dynamics and generate morphological changes.
Antioxidant effects of crude extracts from Baccharis species: inhibition of myeloperoxidase activity, protection against lipid peroxidation, and action as oxidative species scavenger
Vieira, Tiago O.;Seifriz, Ilana;Char?o, Carla C. T.;Oliveira, Simone Q. de;Creczynski-Pasa, Tania B.;
Revista Brasileira de Farmacognosia , 2011, DOI: 10.1590/S0102-695X2011005000091
Abstract: the objective of this study was to show a comparison of the antioxidant properties of aqueous and ethanolic extracts obtained from baccharis articulata (lam.) pers., baccharis trimera (less.) dc., baccharis spicata (lam.) baill. and baccharis usterii heering, asteraceae, by several techniques covering a range of oxidant species and of biotargets. we have investigated the ability of the plant extracts to scavenge dpph (1,1-diphenyl-2-picryl-hydrazyl) free radical, action against lipid peroxidation of membranes including rat liver microsomes and soy bean phosphatidylcholine liposomes by ascorbyl radical and peroxynitrite. hydroxyl radical scavenger activity was measured monitoring the deoxyribose oxidation. the hypochlorous acid scavenger activity was also evaluated by the prevention of protein carbonylation and finally the myeloperoxidase (mpo) activity inhibition. the results obtained suggest that the baccharis extracts studied present a significant antioxidant activity scavenging free radicals and protecting biomolecules from the oxidation. we can suggest that the supposed therapeutic efficacy of this plant could be due, in part, to these properties.
Oxido nítrico: implicaciones fisiopatológicas
Benavides Trujillo,Maria Carolina; Pinzón Tovar,Alejandro;
Revista Colombiana de Anestesiología , 2008,
Abstract: nitric oxide and endothelium-derived relaxing factor were considered a single entity, modulating vascular tone through the stimulated formation of cyclic guanosine 3',5'-monophosphate. nitric oxide (no), produced during the conversion of l-arginine to l-citrulline by no synthase (nos) isoforms, is a gaseous that mediates various functions, including smooth muscle relaxation, neurotransmission, immune cell cytotoxicity, effects of anesthetic agents and nociceptive pathways. this review will consider the biologic actions of nitric oxide.
Evidencias de la participación del peroxinitrito en diversas enfermedades
Chirino, Yolanda I;Orozco-lbarra, Marisol;Pedraza-Chaverrí, José;
Revista de investigación clínica , 2006,
Abstract: peroxynitrite (onoo-) is a reactive nitrogen specie produced by the reaction between nitric oxide (no? ) and super-oxide anion (o2.-). no? is produced by nitric oxide synthase (nos) and o2.- is formed by the addition of an electron to o2 in enzymatic as well as nonenzymatic way. nadph oxidase and xanthine oxidase are some of the enzymes involved in o2.-formation. onoo - is an oxidant specie which is able to modify a great number of biomolecules such as aminoacids, proteins, enzymes and cofactors. onoo - is able to induce nitration leading to the formation of 3-nytrotyrosine. this change has been widely studied, and although it is not only produced by onoo -, but also by other reactive nitrogen species, it has been accepted like footprint of onoo -. the excessive production of reactive nitrogen species is known as nitrosative stress that is able to induce structural damage leading to the loss of cell function. furthermore, synthetic metalloporphyrins that metabolize onoo - in a specific way are being used to determine if onoo - is involved in different diseases, such as alzheimer, huntington, diabetes, hypertension, arthritis, colitis, cardiac and renal complications. finally, these metalloporphyrins may be of potential therapeutic value in diseases related to onoo - production.
Aqueous extract of Salvia officinalis and Ruta graveolens: Potential source of reactive nitrogen species
Al-Nimer Marwan,Ali Eham
International Journal of Green Pharmacy , 2010,
Abstract: There are scarce evidences about the effects of herbs on nitrogen species that induced nitrosative stress. We here investigated the effect of simple water distilled extract of dry leaves salvia officinalis (sage) and Ruta graveolens (Rue) on the nitric oxide (NO) - peroxynitrite (ONOO-) cycle biochemistry in vitro experiments. Aqueous extract of sage or rue (1%) were prepared by simple distillation and scanned by UV-visible spectrophotometer. Their effects were studied on the synthesized ONOO- as well as their ability to generate ONOO. It is ability to donate NO or to scavange released NO by sodium nitroprusside (10 mM) also investigated. UV-visible scan of sage extract revealed the presence of peaks at λ195 and 348.5 while that of rue extract at λ 200, λ242, λ291.5. Both extracts not generate ONOO- radical in form of nitrophenols. Rue extract increased the yield of prepared ONOO- by more than five times. Rue extract donated NO and improved the release NO from sodium nitroprusside while sage extract only improved the release of NO released by sodium nitroprusside. We conclude that simple distilled - aqueous extract of rue and sage extracts improved nitric oxide bioavailability that may be helpful in coronary artery disease with nitrate tolerance.
Impact of two selected non-steroidal anti-inflammation drugs flunixin and ketoprofen on peroxynitrite-induced inflammation and serum levels of cortisol and glucose
M. Ilkhanipour,I. Moghaddami,G. Sadeghi-Hashjin
Koomesh , 2006,
Abstract: Introduction: Peroxynitrite, produced naturally in the body from a reaction between nitric oxide and superoxide anion, possess destructive effects against microorganisms. In excess concentrations, however, it may also lead to cellular damage and inflammatory reactions in the host. Non - sterodial anti inflammation drugs (NSAIDs) are used widely in therapy for their anti-inflammatory, analgesic and antipyretic properties. Meanwhile, their adverse effects on endocrine functions should be taken into account. This project aims at the following goals: 1) establishing a new animal model of peroxynitrite-induced inflammation, 2) studying the effect of two selected NSAIDs on these parameters.3) investigating the possible effect of this oxidant on the blood levels of cortisol and glucose. Material & Methods: 24 male guinea pigs were divided into 4 groups (6 animals in each group). Three groups were injected peroxynitrite and the last group, control group, given physiological salt solution in the paw subcutaneously. Following induction of a local inflammatory response, flunixin meglumine and ketoprofen (0.5 mg/0.5 ml) were injected to second and third groups, 5 times with 12h intervals. First and fourth groups were injected saline solution with the same manner. Animals were anesthetized with thiopental (60 mg/kg, i.p.) and a blood sample was collected by heart puncture. The glucose and cortisol levels of blood were determined by routine laboratory techniques. Result: Blood glucose concentration in the animals that only injected peroxynitrite was less than the control group. In addition, groups which were given drugs had statistically higher levels of glucose in their blood more than the others. Although, cortisol levels were lower in the test groups compared to the control group, these differences were not significant statistically. Conclusion: The results of current study showed that both peroxinitrite and NSAIDs decrease the cortisol levels of blood. These findings can be a possible explanation for the lower levels of cortisol in the blood of patient who receive nitro glisirin as well as osteoarthritis patients that mainly take NSAIDs. In the study, the glucose levels of blood in animals given drugs were more than the control groups.
Antioxidant effects of crude extracts from Baccharis species: inhibition of myeloperoxidase activity, protection against lipid peroxidation, and action as oxidative species scavenger
Tiago O. Vieira,Ilana Seifriz,Carla C. T. Char?o,Simone Q. de Oliveira
Revista Brasileira de Farmacognosia , 2011,
Abstract: The objective of this study was to show a comparison of the antioxidant properties of aqueous and ethanolic extracts obtained from Baccharis articulata (Lam.) Pers., Baccharis trimera (Less.) DC., Baccharis spicata (Lam.) Baill. and Baccharis usterii Heering, Asteraceae, by several techniques covering a range of oxidant species and of biotargets. We have investigated the ability of the plant extracts to scavenge DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical, action against lipid peroxidation of membranes including rat liver microsomes and soy bean phosphatidylcholine liposomes by ascorbyl radical and peroxynitrite. Hydroxyl radical scavenger activity was measured monitoring the deoxyribose oxidation. The hypochlorous acid scavenger activity was also evaluated by the prevention of protein carbonylation and finally the myeloperoxidase (MPO) activity inhibition. The results obtained suggest that the Baccharis extracts studied present a significant antioxidant activity scavenging free radicals and protecting biomolecules from the oxidation. We can suggest that the supposed therapeutic efficacy of this plant could be due, in part, to these properties.
Dual Effects of Interaction Between Meloxicam, Diclofenac Sodium or Tramadol and Nitrogen Species Radicals: In vitro Comparative Study
M.S. M. Al-Nimer,E. A. Ali
International Journal of Pharmacology , 2009,
Abstract: This study aimed to investigate the interaction between synthetic peroxynitrite or sodium nitroprusside (nitric oxide donor) and meloxicam, diclofenac sodium or tramadol HCl. Meloxicam, diclofenac sodium or tramadol HCl (100-500 μg) were incubated in phosphate buffer saline in presence or absence of synthetic peroxynitrite (180 μM) or sodium nitroprusside as nitric oxide donor (10 mM). The level of peroxynitrite and nitric acid in solution were measured using UV-visible spectrophotometer. The results showed that meloxicam scavenged synthetic peroxynitrite and involved in peroxynitrite mediated phenol nitration when it incubated alone in phosphate buffer. All tested compounds, in vitro, behaved like sodium nitroprusside in releasing nitric oxide. Both meloxicam and diclofenac sodium reduced the activity of sodium nitroprusside-releasing nitric oxide. Tramadol HCl was not interacted with sodium nitroprusside at any concentration. We concluded that selective or non selective nonsteroidal anti-inflammatory drugs reduced the activity of nitric oxide donor while tramadol HCl is free from this effect.
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