PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 18280259-0 2008 Nitration of respiratory epithelial cells by myeloperoxidase depends on extracellular nitrite. Nitrites 86-93 myeloperoxidase Homo sapiens 45-60 19836543-2 2009 The method consists of the extraction of MPO from aqueous solutions by immobilized anti-MPO antibodies followed by a washing (to eliminate the extraction medium and the biological fluid with their possible interfering molecules) and the measurement of the activity of MPO with a detection system containing a fluorogenic substrate, H(2)O(2) and nitrite ions as reaction enhancer. Nitrites 345-352 myeloperoxidase Homo sapiens 41-44 16962939-0 2006 Cytotoxicity of myeloperoxidase/nitrite-oxidized low-density lipoprotein toward endothelial cells is due to a high 7beta-hydroxycholesterol to 7-ketocholesterol ratio. Nitrites 32-39 myeloperoxidase Homo sapiens 16-31 17364963-1 2007 Production of nitrogen dioxide by the activity of myeloperoxidase (MPO) in the presence of nitrite is now considered a key step in the pathophysiology of low-density lipoprotein (LDL) oxidation. Nitrites 91-98 myeloperoxidase Homo sapiens 50-65 17364963-1 2007 Production of nitrogen dioxide by the activity of myeloperoxidase (MPO) in the presence of nitrite is now considered a key step in the pathophysiology of low-density lipoprotein (LDL) oxidation. Nitrites 91-98 myeloperoxidase Homo sapiens 67-70 17364963-2 2007 This study shows that betanin, a phytochemical of the betalain class, inhibits the production of lipid hydroperoxides in human LDL submitted to a MPO/nitrite-induced oxidation. Nitrites 150-157 myeloperoxidase Homo sapiens 146-149 17364963-5 2007 In addition, unidentified oxidation product(s) of betanin by MPO/nitrite inhibit(s) the MPO/nitrite-induced LDL oxidation as effectively as the parent compound. Nitrites 65-72 myeloperoxidase Homo sapiens 88-91 17364963-5 2007 In addition, unidentified oxidation product(s) of betanin by MPO/nitrite inhibit(s) the MPO/nitrite-induced LDL oxidation as effectively as the parent compound. Nitrites 92-99 myeloperoxidase Homo sapiens 61-64 17364963-5 2007 In addition, unidentified oxidation product(s) of betanin by MPO/nitrite inhibit(s) the MPO/nitrite-induced LDL oxidation as effectively as the parent compound. Nitrites 92-99 myeloperoxidase Homo sapiens 88-91 16647868-7 2006 We also show that NO2* radicals, generated by a myeloperoxidase/H2O2/nitrite system, also degrade DMPO/HO*. Nitrites 69-76 myeloperoxidase Homo sapiens 48-63 16545248-6 2006 The concentration of MPO was correlated with the concentrations of 8-isoprostane and nitrate, which were normalized to the nitrite concentration. Nitrites 123-130 myeloperoxidase Homo sapiens 21-24 16336215-12 2006 This result is explained by our finding that nitrite reacts 10-fold faster with compound II of eosinophil peroxidase than with the analogous redox intermediate of myeloperoxidase. Nitrites 45-52 myeloperoxidase Homo sapiens 163-178 15203186-9 2004 Nitrite--recently found to be a substrate for MPO--showed some competing properties. Nitrites 0-7 myeloperoxidase Homo sapiens 46-49 16443167-4 2006 In the presence of chloride, bromide, and nitrite, the myeloperoxidase-hydrogen peroxide system caused an oxidation, bromination, and nitrosylation/nitration of eight amino acid residues of albumin as detected by fragment analysis of tryptic digests with matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Nitrites 42-49 myeloperoxidase Homo sapiens 55-70 15493876-1 2004 Oxidative modification of low-density lipoprotein (LDL) is a pivotal process in early atherogenesis and can be brought about by myeloperoxidase (MPO), which is capable of reacting with nitrite, a NO metabolite. Nitrites 185-192 myeloperoxidase Homo sapiens 128-143 15493876-1 2004 Oxidative modification of low-density lipoprotein (LDL) is a pivotal process in early atherogenesis and can be brought about by myeloperoxidase (MPO), which is capable of reacting with nitrite, a NO metabolite. Nitrites 185-192 myeloperoxidase Homo sapiens 145-148 15493876-2 2004 We studied MPO-mediated formation of conjugated dienes in isolated human LDL in dependence on the concentrations of nitrite and chloride. Nitrites 116-123 myeloperoxidase Homo sapiens 11-14 15493876-6 2004 We propose a prominent role of lipid peroxidation for the proatherogenic action of the MPO/nitrite system, whereas peroxynitrite may be competent for protein tyrosine nitration of LDL. Nitrites 91-98 myeloperoxidase Homo sapiens 87-90 15493876-7 2004 Monomeric and oligomeric flavan-3-ols present in cocoa products effectively counteracted, at micromolar concentrations, the MPO/nitrite-mediated lipid peroxidation of LDL. Nitrites 128-135 myeloperoxidase Homo sapiens 124-127 13679077-5 2003 Another potential source of reactive nitrogen species is the myeloperoxidase-hydrogen peroxide-nitrite system of activated phagocytes. Nitrites 95-102 myeloperoxidase Homo sapiens 61-76 15354951-8 2004 Another oxide of nitrogen, nitrite, is a good substrate for myeloperoxidase Compound I but slowly reacts with Compound II. Nitrites 27-34 myeloperoxidase Homo sapiens 60-75 15354951-9 2004 Nitrogen dioxide is formed after nitrite oxidation by myeloperoxidase. Nitrites 33-40 myeloperoxidase Homo sapiens 54-69 14657339-8 2003 Scavenging free NO from the iNOS milieu by the MPO/H2O2 system subsequently restores the full capacity of iNOS to convert L-arginine to product (NO), as judged by the increase in the rates of citrulline and nitrite/nitrate production. Nitrites 207-214 myeloperoxidase Homo sapiens 47-50 13679077-9 2003 Xanthine nitration by myeloperoxidase required hydrogen peroxide and nitrite. Nitrites 69-76 myeloperoxidase Homo sapiens 22-37 12606047-0 2003 Myeloperoxidase/nitrite-mediated lipid peroxidation of low-density lipoprotein as modulated by flavonoids. Nitrites 16-23 myeloperoxidase Homo sapiens 0-15 12797467-1 2003 Myeloperoxidase (MPO) catalyzes a nitration reaction to form nitrotyrosine in the presence of high nitrite, the metabolite of NO. Nitrites 99-106 myeloperoxidase Homo sapiens 0-15 12797467-1 2003 Myeloperoxidase (MPO) catalyzes a nitration reaction to form nitrotyrosine in the presence of high nitrite, the metabolite of NO. Nitrites 99-106 myeloperoxidase Homo sapiens 17-20 12797467-2 2003 Human leukocyte was shown to cause phenolic nitration using released MPO as a catalyst in the presence of nitrite. Nitrites 106-113 myeloperoxidase Homo sapiens 69-72 12797467-10 2003 We conclude that MPO may act predominantly to scavenge nitrotyrosine under physiological nitrite condition, and protect against injurious effect of nitrotyrosine. Nitrites 89-96 myeloperoxidase Homo sapiens 17-20 12606047-1 2003 In the presence of a H(2)O(2)-generating system, myeloperoxidase (MPO) caused conjugated diene formation in low-density lipoprotein (LDL), indicating lipid peroxidation which was dependent on nitrite but not on chloride. Nitrites 192-199 myeloperoxidase Homo sapiens 49-64 12606047-1 2003 In the presence of a H(2)O(2)-generating system, myeloperoxidase (MPO) caused conjugated diene formation in low-density lipoprotein (LDL), indicating lipid peroxidation which was dependent on nitrite but not on chloride. Nitrites 192-199 myeloperoxidase Homo sapiens 66-69 12606047-4 2003 The MPO-catalyzed oxidation of flavonoids was accelerated in the presence of nitrite. Nitrites 77-84 myeloperoxidase Homo sapiens 4-7 12612415-0 2003 Modification by fluoride, bromide, iodide, thiocyanate and nitrite anions of reaction of a myeloperoxidase-H2O2-Cl- system with nucleosides. Nitrites 59-66 myeloperoxidase Homo sapiens 91-106 11960752-1 2002 Myeloperoxidase, in the presence of hydrogen peroxide and nitrite, promotes the lipid peroxidation of low density lipoprotein (LDL); the modified lipoprotein is then capable of being readily endocytosed by macrophages. Nitrites 58-65 myeloperoxidase Homo sapiens 0-15 11054430-0 2001 The nitric oxide congener nitrite inhibits myeloperoxidase/H2O2/ Cl- -mediated modification of low density lipoprotein. Nitrites 26-33 myeloperoxidase Homo sapiens 43-58 11515815-5 2001 Nitrite, produced at high concentrations from NO during inflammation, can react with neutrophil myeloperoxidase-derived hypochlorous acid (HOCl) to form the active oxidant nitryl chloride, a species capable of nitrating tyrosine and tyrosyl residues on proteins. Nitrites 0-7 myeloperoxidase Homo sapiens 96-111 11288757-11 2001 Serum total nitrite correlated (Pearson product moment) with percentage of neutrophils in BALF (R = 0.650, P < 0.0001), MPO (R = 0.431, P = 0.0055), change in FEV1 from baseline (deltaFEV1) (R = -0348, P = 0.0298), and days after transplantation (R = 0.345, P = 0.0294). Nitrites 12-19 myeloperoxidase Homo sapiens 123-126 11054430-3 2001 Furthermore, hypochlorous acid (HOCl), the major strong oxidant generated by MPO in the presence of physiological concentrations of chloride ions, can also react with nitrite, forming the reactive intermediate nitryl chloride. Nitrites 167-174 myeloperoxidase Homo sapiens 77-80 11054430-5 2001 Interestingly, nitrite concentrations as low as 12.5 and 25 microm significantly decreased MPO/H2O2)/Cl- -induced modification of apoB lysine residues, formation of N-chloramines, and increases in the relative electrophoretic mobility of LDL. Nitrites 15-22 myeloperoxidase Homo sapiens 91-94 11054430-7 2001 Furthermore, experiments using ascorbate (12.5-200 microm) and the tyrosine analogue 4-hydroxyphenylacetic acid (12.5-200 microm), which are both substrates of MPO, indicated that nitrite inhibits MPO-mediated LDL modifications by trapping the enzyme in its inactive compound II form. Nitrites 180-187 myeloperoxidase Homo sapiens 160-163 11054430-7 2001 Furthermore, experiments using ascorbate (12.5-200 microm) and the tyrosine analogue 4-hydroxyphenylacetic acid (12.5-200 microm), which are both substrates of MPO, indicated that nitrite inhibits MPO-mediated LDL modifications by trapping the enzyme in its inactive compound II form. Nitrites 180-187 myeloperoxidase Homo sapiens 197-200 11054430-2 2001 Recent studies have shown that myeloperoxidase (MPO), an abundant heme protein released by activated leukocytes, can oxidize nitrite (NO(2-)) to a radical species, most likely nitrogen dioxide. Nitrites 125-132 myeloperoxidase Homo sapiens 31-46 11054430-2 2001 Recent studies have shown that myeloperoxidase (MPO), an abundant heme protein released by activated leukocytes, can oxidize nitrite (NO(2-)) to a radical species, most likely nitrogen dioxide. Nitrites 125-132 myeloperoxidase Homo sapiens 48-51 10777476-0 2000 Mechanism of reaction of myeloperoxidase with nitrite. Nitrites 46-53 myeloperoxidase Homo sapiens 25-40 10777476-2 2000 In order to clarify if nitrite could be a physiological substrate of myeloperoxidase, we investigated the reactions of the ferric enzyme and its redox intermediates, compound I and compound II, with nitrite under pre-steady state conditions by using sequential mixing stopped-flow analysis in the pH range 4-8. Nitrites 23-30 myeloperoxidase Homo sapiens 69-84 10777476-2 2000 In order to clarify if nitrite could be a physiological substrate of myeloperoxidase, we investigated the reactions of the ferric enzyme and its redox intermediates, compound I and compound II, with nitrite under pre-steady state conditions by using sequential mixing stopped-flow analysis in the pH range 4-8. Nitrites 199-206 myeloperoxidase Homo sapiens 69-84 10777476-3 2000 At 15 degrees C the rate of formation of the low spin MPO-nitrite complex is (2.5 +/- 0.2) x 10(4) m(-1) s(-1) at pH 7 and (2.2 +/- 0.7) x 10(6) m(-1) s(-1) at pH 5. Nitrites 58-65 myeloperoxidase Homo sapiens 54-57 10777476-5 2000 Nitrite is oxidized by two one-electron steps in the MPO peroxidase cycle. Nitrites 0-7 myeloperoxidase Homo sapiens 53-56 20692968-4 1994 Addition of nitrite to the MPO/H(2)O(2) system markedly increased the formation of (+)-anti-BPDE. Nitrites 12-19 myeloperoxidase Homo sapiens 27-30 10766781-0 2000 Nitrite as a substrate and inhibitor of myeloperoxidase. Nitrites 0-7 myeloperoxidase Homo sapiens 40-55 10766781-5 2000 Nitrite was found to be a poor substrate for myeloperoxidase but an excellent inhibitor of its chlorination activity. Nitrites 0-7 myeloperoxidase Homo sapiens 45-60 10766781-7 2000 In the presence of physiological concentrations of nitrite and chloride, myeloperoxidase catalyzed little nitration of tyrosyl residues in a heptapeptide. Nitrites 51-58 myeloperoxidase Homo sapiens 73-88 10766781-11 2000 With neutrophils, myeloperoxidase-dependent nitration required a high concentration of nitrite (1 mM), was doubled by tyrosine, and increased 4-fold by superoxide dismutase. Nitrites 87-94 myeloperoxidase Homo sapiens 18-33 10766781-13 2000 We propose that at sites of inflammation myeloperoxidase will nitrate proteins, even though nitrite is a poor substrate, because the co-substrate tyrosine will be available to facilitate the reaction. Nitrites 92-99 myeloperoxidase Homo sapiens 41-56 10437781-0 1999 Nitrogen dioxide radical generated by the myeloperoxidase-hydrogen peroxide-nitrite system promotes lipid peroxidation of low density lipoprotein. Nitrites 76-83 myeloperoxidase Homo sapiens 42-57 10437781-3 1999 We found that myeloperoxidase, an H2O2-generating system and nitrite (NO2-) peroxidized LDL lipids. Nitrites 61-68 myeloperoxidase Homo sapiens 14-29 9686606-12 1998 Peroxynitrite alone mediated cross-linking (100 microM ONOO-: 40.3+/-1.9% cross-linking; p < 0.002), and the addition of MPO significantly enhanced this effect (100 microM: 57.7+/-6.0%; p < 0.0002 with respect to no nitrite control). Nitrites 6-13 myeloperoxidase Homo sapiens 124-127 10029554-0 1999 8-Nitro-2"-deoxyguanosine, a specific marker of oxidation by reactive nitrogen species, is generated by the myeloperoxidase-hydrogen peroxide-nitrite system of activated human phagocytes. Nitrites 142-149 myeloperoxidase Homo sapiens 108-123 9450756-4 1998 We have recently demonstrated that nitrite (NO2-), a major end-product of .NO metabolism, readily promotes tyrosine nitration through formation of nitryl chloride (NO2Cl) and nitrogen dioxide (.NO2) by reaction with the inflammatory mediators hypochlorous acid (HOCl) or myeloperoxidase. Nitrites 35-42 myeloperoxidase Homo sapiens 271-286 20692968-5 1994 Taken together, the results indicate that the principal pathway for the nitrite-stimulated formation of (+)-anti-BPDE in PMA-activated PMNs involves participation of MPO, whereas alternative pathways seem to be operative in the formation of BP-7,8-dione. Nitrites 72-79 myeloperoxidase Homo sapiens 166-169 2029741-4 1991 Sodium azide, an inhibitor of myeloperoxidase and catalase, reduced the nitrite-stimulated metabolism of BP-7,8-diol in PMA-activated leukocytes. Nitrites 72-79 myeloperoxidase Homo sapiens 30-45 8180968-5 1994 Preliminary experiments suggest that nitrite stimulates the metabolism of (-)-BP-7,8-diol by direct interaction with myeloperoxidase and hydrogen peroxide. Nitrites 37-44 myeloperoxidase Homo sapiens 117-132 1333417-0 1992 Interaction of human myeloperoxidase with nitrite. Nitrites 42-49 myeloperoxidase Homo sapiens 21-36 1333417-1 1992 EPR (electron paramagnetic resonance) and optical spectroscopy show that human neutrophil myeloperoxidase is converted from ferric high-spin to low-spin by the addition of nitrite. Nitrites 172-179 myeloperoxidase Homo sapiens 90-105 32496983-8 2020 Protein nitration also occurs by activation of myeloperoxidase and H2O2, promoting oxidation of nitrite (NO2 - ). Nitrites 96-103 myeloperoxidase Homo sapiens 47-62 23059132-9 2012 Notably, diversion of MPO from HOCl production by thiocyanate or nitrite attenuated de-adhesion and associated signaling responses, despite the latter substrate supporting MPO-catalyzed fibronectin nitration. Nitrites 65-72 myeloperoxidase Homo sapiens 22-25 21657847-1 2011 AIMS: Elevation of the leukocyte enzyme myeloperoxidase (MPO) in stable coronary artery disease (CAD) is controversial and its relationship with oxidized low-density lipoprotein (ox-LDL) and nitrite/nitrate (NOx) levels in CAD patients has not been evaluated. Nitrites 191-198 myeloperoxidase Homo sapiens 40-55 21657847-1 2011 AIMS: Elevation of the leukocyte enzyme myeloperoxidase (MPO) in stable coronary artery disease (CAD) is controversial and its relationship with oxidized low-density lipoprotein (ox-LDL) and nitrite/nitrate (NOx) levels in CAD patients has not been evaluated. Nitrites 191-198 myeloperoxidase Homo sapiens 57-60 29529688-7 2019 RESULTS: The mean concentration of myeloperoxidase was significantly higher in the diabetic group compared to the control group (16.2+-4.9 vs. 3.7+-1.8; P<0.001).The nitrite concentration was comparable in both groups while the concentration of nitrate was significantly higher in the diabetic group (41.2 [42.9] vs 31.9 [23]; P=0.017). Nitrites 169-176 myeloperoxidase Homo sapiens 35-50 27020551-0 2016 Inhibition of myeloperoxidase-mediated oxidative damage by nitrite in SH-SY5Y cells: Relevance to neuroprotection in neurodegenerative diseases. Nitrites 59-66 myeloperoxidase Homo sapiens 14-29 25731855-4 2015 The efficiency of MPO to remove peroxynitrite was enhanced by L-tyrosine, nitrite and (-)-epicatechin, substances known to reduce Compound II with high reaction rate. Nitrites 38-45 myeloperoxidase Homo sapiens 18-21 26105861-10 2013 In the subgroup CC+CT the MPO levels were higher in HBP as well as nitrites, leucocytes, neutrophils, Apo B, BMI, waist and ratio waist/hip compared with NT (p<0.001, p=0.04, p=0.042, p=0.035, p=0.03, p=0.022, p=0.026, respectively). Nitrites 67-75 myeloperoxidase Homo sapiens 26-29