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Alan Chait - One of the best experts on this subject based on the ideXlab platform.
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human atherosclerotic intima and blood of patients with established coronary artery disease contain high density lipoprotein damaged by Reactive Nitrogen species
Journal of Biological Chemistry, 2004Co-Authors: Subramaniam Pennathur, Jaeman Byun, Constanze Bergt, Baohai Shao, Sean Y Kassim, Pragya Singh, Pattie S Green, Thomas O Mcdonald, John D Brunzell, Alan ChaitAbstract:Abstract High density lipoprotein (HDL) is the major carrier of lipid hydroperoxides in plasma, but it is not yet established whether HDL proteins are damaged by Reactive Nitrogen species in the circulation or artery wall. One pathway that generates such species involves myeloperoxidase (MPO), a major constituent of artery wall macrophages. Another pathway involves peroxynitrite, a potent oxidant generated in the reaction of nitric oxide with superoxide. Both MPO and peroxynitrite produce 3-nitrotyrosine in vitro. To investigate the involvement of Reactive Nitrogen species in atherogenesis, we quantified 3-nitrotyrosine levels in HDL in vivo. The mean level of 3-nitrotyrosine in HDL isolated from human aortic atherosclerotic intima was 6-fold higher (619 ± 178 μmol/mol Tyr) than that in circulating HDL (104 ± 11 μmol/mol Tyr; p < 0.01). Immunohistochemical studies demonstrated striking colocalization of MPO with epitopes Reactive with an antibody to 3-nitrotyrosine. However, there was no significant correlation between the levels of 3-chlorotyrosine, a specific product of MPO, and those of 3-nitrotyrosine in lesion HDL. We also detected 3-nitrotyrosine in circulating HDL, and linear regression analysis demonstrated a strong correlation between the levels of 3-chlorotyrosine and levels of 3-nitrotyrosine. These observations suggest that MPO promotes the formation of 3-chlorotyrosine and 3-nitrotyrosine in circulating HDL but that other pathways also produce 3-nitrotyrosine in atherosclerotic tissue. Levels of HDL isolated from plasma of patients with established coronary artery disease contained twice as much 3-nitrotyrosine as HDL from plasma of healthy subjects, suggesting that nitrated HDL might be a marker for clinically significant vascular disease. The detection of 3-nitrotyrosine in HDL raises the possibility that Reactive Nitrogen species derived from nitric oxide might promote atherogenesis. Thus, nitrated HDL might represent a previously unsuspected link between nitrosative stress, atherosclerosis, and inflammation.
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human atherosclerotic intima and blood of patients with established coronary artery disease contain high density lipoprotein damaged by Reactive Nitrogen species
Journal of Biological Chemistry, 2004Co-Authors: Subramaniam Pennathur, Jaeman Byun, Constanze Bergt, Baohai Shao, Sean Y Kassim, Pragya Singh, Pattie S Green, Thomas O Mcdonald, John D Brunzell, Alan ChaitAbstract:High density lipoprotein (HDL) is the major carrier of lipid hydroperoxides in plasma, but it is not yet established whether HDL proteins are damaged by Reactive Nitrogen species in the circulation or artery wall. One pathway that generates such species involves myeloperoxidase (MPO), a major constituent of artery wall macrophages. Another pathway involves peroxynitrite, a potent oxidant generated in the reaction of nitric oxide with superoxide. Both MPO and peroxynitrite produce 3-nitrotyrosine in vitro. To investigate the involvement of Reactive Nitrogen species in atherogenesis, we quantified 3-nitrotyrosine levels in HDL in vivo. The mean level of 3-nitrotyrosine in HDL isolated from human aortic atherosclerotic intima was 6-fold higher (619 ± 178 μmol/mol Tyr) than that in circulating HDL (104 ± 11 μmol/mol Tyr; p
Bruce A. Freeman - One of the best experts on this subject based on the ideXlab platform.
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Biological aspects of Reactive Nitrogen species.
Biochimica et biophysica acta, 1999Co-Authors: Rakesh P. Patel, Joanne Mcandrew, Hassan Sellak, C. Roger White, Bruce A. Freeman, Victor M. Darley-usmarAbstract:Nitric oxide (NO) plays an important role as a cell-signalling molecule, anti-infective agent and, as most recently recognised, an antioxidant. The metabolic fate of NO gives rise to a further series of compounds, collectively known as the Reactive Nitrogen species (RNS), which possess their own unique characteristics. In this review we discuss this emerging aspect of the NO field in the context of the formation of the RNS and what is known about their effects on biological systems. While much of the insight into the RNS has been gained from the extensive chemical characterisation of these species, to reveal biological consequences this approach must be complemented by direct measures of physiological function. Although we do not know the consequences of many of the dominant chemical reactions of RNS an intriguing aspect is now emerging. This review will illustrate how, when specificity and amplification through cell signalling mechanisms are taken into account, the less significant reactions, in terms of yield or rates, can explain many of the biological responses of exposure of cells or physiological systems to RNS.
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nitration of unsaturated fatty acids by nitric oxide derived Reactive Nitrogen species peroxynitrite nitrous acid Nitrogen dioxide and nitronium ion
Chemical Research in Toxicology, 1999Co-Authors: Valerie B Odonnell, Jason P. Eiserich, Phillip Chumley, Michael J Jablonsky, Rama N Krishna, Marion Kirk, Stephen Barnes, Bruce A. FreemanAbstract:Reactive Nitrogen species derived from nitric oxide are potent oxidants formed during inflammation that can oxidize membrane and lipoprotein lipids in vivo. Herein, it is demonstrated that several ...
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nitration of unsaturated fatty acids by nitric oxide derived Reactive Nitrogen species peroxynitrite nitrous acid Nitrogen dioxide and nitronium ion
Chemical Research in Toxicology, 1999Co-Authors: Valerie B Odonnell, Jason P. Eiserich, Phillip Chumley, Michael J Jablonsky, Rama N Krishna, Marion Kirk, Stephen Barnes, Bruce A. FreemanAbstract:Reactive Nitrogen species derived from nitric oxide are potent oxidants formed during inflammation that can oxidize membrane and lipoprotein lipids in vivo. Herein, it is demonstrated that several of these species react with unsaturated fatty acid to yield nitrated oxidation products. Using HPLC coupled with both UV detection and electrospray ionization mass spectrometry, products of reaction of ONOO- with linoleic acid displayed mass/charge (m/z) characteristics of LNO2 (at least three products at m/z 324, negative ion mode). Further analysis by MS/MS gave a major fragment at m/z 46. Addition of a NO2 group was confirmed using [15N]ONOO- which gave a product at m/z 325, fragmenting to form a daughter ion at m/z 47. Formation of nitrated lipids was inhibited by bicarbonate, superoxide dismutase (SOD), and Fe3+−EDTA, while the yield of oxidation products was decreased by bicarbonate and SOD, but not by Fe3+−EDTA. Reaction of linoleic acid with both Nitrogen dioxide (•NO2) or nitronium tetrafluoroborate (NO...
Francisco J. Corpas - One of the best experts on this subject based on the ideXlab platform.
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Peroxisomes as cell generators of Reactive Nitrogen species (RNS) signal molecules.
Sub-cellular biochemistry, 2013Co-Authors: Francisco J. Corpas, José M. Palma, Juan B. Barroso, Luis A. Del RíoAbstract:Nitric oxide is a gaseous free radical with a wide range of direct and indirect actions in plant cells. However, the enzymatic sources of NO and its subcellular localization in plants are still under debate. Among the different subcellular compartments where NO has been found to be produced, peroxisomes are the best characterized since in these organelles it has been demonstrated the presence of NO and it has been biochemically characterized a L-arginine-dependent nitric oxide synthase activity. This chapter summarizes the present knowledge of the NO metabolism and its derived Reactive Nitrogen species (RNS) in plant peroxisomes and how this gaseous free radical is involved in natural senescence, and is released to the cytosol under salinity stress conditions acting as a signal molecule.
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metabolism of Reactive oxygen species and Reactive Nitrogen species in pepper capsicum annuum l plants under low temperature stress
Plant Cell and Environment, 2012Co-Authors: Morad Airaki, José M. Palma, Luis A. Del Río, Juan B. Barroso, Mounira Chaki, Raquel Valderrama, Marina Leterrier, Rosa M Mateos, Francisco J. CorpasAbstract:Low temperature is an environmental stress that affects crop production and quality and regulates the expression of many genes, and the level of a number of proteins and metabolites. Using leaves from pepper (Capsicum annum L.) plants exposed to low temperature (8 °C) for different time periods (1 to 3 d), several key components of the metabolism of Reactive Nitrogen and oxygen species (RNS and ROS, respectively) were analysed. After 24 h of exposure at 8 °C, pepper plants exhibited visible symptoms characterized by flaccidity of stems and leaves. This was accompanied by significant changes in the metabolism of RNS and ROS with an increase of both protein tyrosine nitration (NO2-Tyr) and lipid peroxidation, indicating that low temperature induces nitrosative and oxidative stress. During the second and third days at low temperature, pepper plants underwent cold acclimation by adjusting their antioxidant metabolism and reverting the observed nitrosative and oxidative stress. In this process, the levels of the soluble non-enzymatic antioxidants ascorbate and glutathione, and the activity of the main NADPH-generating dehydrogenases were significantly induced. This suggests that ascorbate, glutathione and the NADPH-generating dehydrogenases have a role in the process of cold acclimation through their effect on the redox state of the cell.
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involvement of Reactive Nitrogen and oxygen species rns and ros in sunflower mildew interaction
Plant and Cell Physiology, 2009Co-Authors: Mounira Chaki, Francisco J. Corpas, Ana Fernandezocana, Raquel Valderrama, Alfonso Carreras, Juan C Begaramorales, Francisco J Esteban, Francisco Luque, Maria V Gomezrodriguez, Juan B. BarrosoAbstract:Nitric oxide (.NO) has been shown to participate in plant response against pathogen infection; however, less is known of the participation of other NO-derived molecules designated as Reactive Nitrogen species (RNS). Using two sunflower (Helianthus annuus L.) cultivars with different sensitivity to infection by the pathogen Plasmopara halstedii, we studied key components involved in RNS and ROS metabolism. We analyzed the superoxide radical production, hydrogen peroxide content, l-arginine-dependent nitric oxide synthase (NOS) and S-nitrosoglutathione reductase (GSNOR) activities. Furthermore, we examined the location and contents of .NO, S-nitrosothiols (RSNOs), S-nitrosoglutathione (GSNO) and protein 3-nitrotyrosine (NO(2)-Tyr) by confocal laser scanning microscopy (CLSM) and biochemical analyses. In the susceptible cultivar, the pathogen induces an increase in proteins that undergo tyrosine nitration accompanied by an augmentation in RSNOs. This rise of RSNOs seems to be independent of the enzymatic generation of .NO because the l-arginine-dependent NOS activity is reduced after infection. These results suggest that pathogens induce nitrosative stress in susceptible cultivars. In contrast, in the resistant cultivar, no increase of RSNOs or tyrosine nitration of proteins was observed, implying an absence of nitrosative stress. Therefore, it is proposed that the increase of tyrosine nitration of proteins can be considered a general biological marker of nitrosative stress in plants under biotic conditions.
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metabolism of Reactive Nitrogen species in pea plants under abiotic stress conditions
Plant and Cell Physiology, 2008Co-Authors: Francisco J. Corpas, José M. Palma, Luis A. Del Río, Mounira Chaki, Ana Fernandezocana, Raquel Valderrama, Alfonso Carreras, Juan C Begaramorales, Morad Airaki, Juan B. BarrosoAbstract:Nitric oxide (*NO) is a key signaling molecule in different physiological processes of animals and plants. However, little is known about the metabolism of endogenous *NO and other Reactive Nitrogen species (RNS) in plants under abiotic stress conditions. Using pea plants exposed to six different abiotic stress conditions (high light intensity, low and high temperature, continuous light, continuous dark and mechanical wounding), several key components of the metabolism of RNS including the content of *NO, S-nitrosothiols (RSNOs) and nitrite plus nitrate, the enzyme activities of l-arginine-dependent nitric oxide synthase (NOS) and S-nitrosogluthathione reductase (GSNOR), and the profile of protein tyrosine nitration (NO(2)-Tyr) were analyzed in leaves. Low temperature was the stress that produced the highest increase of NOS and GSNOR activities, and this was accompanied by an increase in the content of total *NO and S-nitrosothiols, and an intensification of the immunoreactivity with an antibody against NO(2)-Tyr. Mechanical wounding, high temperature and light also had a clear activating effect on the different indicators of RNS metabolism in pea plants. However, the total content of nitrite and nitrate in leaves was not affected by any of these stresses. Considering that protein tyrosine nitration is a potential marker of nitrosative stress, the results obtained suggest that low and high temperature, continuous light and high light intensity are abiotic stress conditions that can induce nitrosative stress in pea plants.
M A Sutton - One of the best experts on this subject based on the ideXlab platform.
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Reactive Nitrogen in atmospheric emission inventories
Atmospheric Chemistry and Physics, 2009Co-Authors: Stefan Reis, R W Pinder, Meigen Zhang, G Lijie, M A SuttonAbstract:Excess Reactive Nitrogen (Nr) has become one of the most pressing environmental problems leading to air pol- lution, acidification and eutrophication of ecosystems, bio- diversity impacts, leaching of nitrates into groundwater and global warming. This paper investigates how current inven- tories cover emissions of Nr to the atmosphere in Europe, the United States of America, and China. The focus is on anthro- pogenic sources, assessing the state-of-the-art of quantifying emissions of Ammonia (NH3), Nitrogen Oxides (NOx) and Nitrous Oxide (N2O), the different purposes for which inven- tories are compiled, and to which extent current inventories meet the needs of atmospheric dispersion modelling. The paper concludes with a discussion of uncertainties involved and a brief outlook on emerging trends in the three regions investigated is conducted. Key issues are substantial differences in the overall mag- nitude, but as well in the relative sectoral contribution of emissions in the inventories that have been assessed. While these can be explained by the use of different methodologies and underlying data (e.g. emission factors or activity rates), they may lead to quite different results when using the emis- sion datasets to model ambient air quality or the deposition with atmospheric dispersion models. Hence, differences and uncertainties in emission inventories are not merely of aca- demic interest, but can have direct policy implications when the development of policy actions is based on these model results. The level of uncertainty of emission estimates varies greatly between substances, regions and emission source sec- tors. This has implications for the direction of future research needs and indicates how existing gaps between modelled and measured concentration or deposition rates could be most ef- ficiently addressed.
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Reactive Nitrogen in atmospheric emission inventories
Atmospheric Chemistry and Physics, 2009Co-Authors: Stefan Reis, R W Pinder, Meigen Zhang, G Lijie, M A SuttonAbstract:Abstract. Excess Reactive Nitrogen (Nr) has become one of the most pressing environmental problems leading to air pollution, acidification and eutrophication of ecosystems, biodiversity impacts, leaching of nitrates into groundwater and global warming. This paper investigates how current inventories cover emissions of Nr to the atmosphere in Europe, the United States of America, and China. The focus is on anthropogenic sources, assessing the state-of-the-art of quantifying emissions of Ammonia (NH3), Nitrogen Oxides (NOx) and Nitrous Oxide (N2O), the different purposes for which inventories are compiled, and to which extent current inventories meet the needs of atmospheric dispersion modelling. The paper concludes with a discussion of uncertainties involved and a brief outlook on emerging trends in the three regions investigated is conducted. Key issues are substantial differences in the overall magnitude, but as well in the relative sectoral contribution of emissions in the inventories that have been assessed. While these can be explained by the use of different methodologies and underlying data (e.g. emission factors or activity rates), they may lead to quite different results when using the emission datasets to model ambient air quality or the deposition with atmospheric dispersion models. Hence, differences and uncertainties in emission inventories are not merely of academic interest, but can have direct policy implications when the development of policy actions is based on these model results. The level of uncertainty of emission estimates varies greatly between substances, regions and emission source sectors. This has implications for the direction of future research needs and indicates how existing gaps between modelled and measured concentration or deposition rates could be most efficiently addressed. The observed current trends in emissions display decreasing NOx emissions and only slight reductions for NH3 in both Europe and the US. However, in China projections indicate a steep increase of both.
Subramaniam Pennathur - One of the best experts on this subject based on the ideXlab platform.
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human atherosclerotic intima and blood of patients with established coronary artery disease contain high density lipoprotein damaged by Reactive Nitrogen species
Journal of Biological Chemistry, 2004Co-Authors: Subramaniam Pennathur, Jaeman Byun, Constanze Bergt, Baohai Shao, Sean Y Kassim, Pragya Singh, Pattie S Green, Thomas O Mcdonald, John D Brunzell, Alan ChaitAbstract:Abstract High density lipoprotein (HDL) is the major carrier of lipid hydroperoxides in plasma, but it is not yet established whether HDL proteins are damaged by Reactive Nitrogen species in the circulation or artery wall. One pathway that generates such species involves myeloperoxidase (MPO), a major constituent of artery wall macrophages. Another pathway involves peroxynitrite, a potent oxidant generated in the reaction of nitric oxide with superoxide. Both MPO and peroxynitrite produce 3-nitrotyrosine in vitro. To investigate the involvement of Reactive Nitrogen species in atherogenesis, we quantified 3-nitrotyrosine levels in HDL in vivo. The mean level of 3-nitrotyrosine in HDL isolated from human aortic atherosclerotic intima was 6-fold higher (619 ± 178 μmol/mol Tyr) than that in circulating HDL (104 ± 11 μmol/mol Tyr; p < 0.01). Immunohistochemical studies demonstrated striking colocalization of MPO with epitopes Reactive with an antibody to 3-nitrotyrosine. However, there was no significant correlation between the levels of 3-chlorotyrosine, a specific product of MPO, and those of 3-nitrotyrosine in lesion HDL. We also detected 3-nitrotyrosine in circulating HDL, and linear regression analysis demonstrated a strong correlation between the levels of 3-chlorotyrosine and levels of 3-nitrotyrosine. These observations suggest that MPO promotes the formation of 3-chlorotyrosine and 3-nitrotyrosine in circulating HDL but that other pathways also produce 3-nitrotyrosine in atherosclerotic tissue. Levels of HDL isolated from plasma of patients with established coronary artery disease contained twice as much 3-nitrotyrosine as HDL from plasma of healthy subjects, suggesting that nitrated HDL might be a marker for clinically significant vascular disease. The detection of 3-nitrotyrosine in HDL raises the possibility that Reactive Nitrogen species derived from nitric oxide might promote atherogenesis. Thus, nitrated HDL might represent a previously unsuspected link between nitrosative stress, atherosclerosis, and inflammation.
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human atherosclerotic intima and blood of patients with established coronary artery disease contain high density lipoprotein damaged by Reactive Nitrogen species
Journal of Biological Chemistry, 2004Co-Authors: Subramaniam Pennathur, Jaeman Byun, Constanze Bergt, Baohai Shao, Sean Y Kassim, Pragya Singh, Pattie S Green, Thomas O Mcdonald, John D Brunzell, Alan ChaitAbstract:High density lipoprotein (HDL) is the major carrier of lipid hydroperoxides in plasma, but it is not yet established whether HDL proteins are damaged by Reactive Nitrogen species in the circulation or artery wall. One pathway that generates such species involves myeloperoxidase (MPO), a major constituent of artery wall macrophages. Another pathway involves peroxynitrite, a potent oxidant generated in the reaction of nitric oxide with superoxide. Both MPO and peroxynitrite produce 3-nitrotyrosine in vitro. To investigate the involvement of Reactive Nitrogen species in atherogenesis, we quantified 3-nitrotyrosine levels in HDL in vivo. The mean level of 3-nitrotyrosine in HDL isolated from human aortic atherosclerotic intima was 6-fold higher (619 ± 178 μmol/mol Tyr) than that in circulating HDL (104 ± 11 μmol/mol Tyr; p
