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Stefan L. Marklund - One of the best experts on this subject based on the ideXlab platform.
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two Superoxide Dismutase prion strains transmit amyotrophic lateral sclerosis like disease
Journal of Clinical Investigation, 2016Co-Authors: Elaheh Ekhtiari Bidhendi, Stefan L. Marklund, Johan Bergh, Per Zetterstrom, Peter M Andersen, Thomas BrannstromAbstract:Amyotrophic lateral sclerosis (ALS) is an adult-onset degeneration of motor neurons that is commonly caused by mutations in the gene encoding Superoxide Dismutase 1 (SOD1). Both patients and Tg mic ...
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interleukin 1alpha downregulates extracellular Superoxide Dismutase in human corneal keratoconus stromal cells
Molecular Vision, 2007Co-Authors: Eva Olofsson, Stefan L. Marklund, Fatima Pedrosadomellof, Anders BehndigAbstract:PURPOSE: The purpose of this investigation was to elucidate the regulation of corneal extracellular Superoxide Dismutase (SOD3) synthesis in keratoconus. We compared the basal and cytokine-regulate ...
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The coupling between disulphide status, metallation and dimer interface strength in Cu/Zn Superoxide Dismutase.
Journal of Molecular Biology, 2006Co-Authors: A. Hornberg, Derek T. Logan, Stefan L. Marklund, Mikael OlivebergAbstract:The coupling between disulphide status, metallation and dimer interface strength in Cu/Zn Superoxide Dismutase.
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Phenotypic heterogeneity in motor neuron disease patients with CuZn-Superoxide Dismutase mutations in Scandinavia
Brain, 1997Co-Authors: P M Andersen, M. L. Keränen, M. Karlsborg, Lars Forsgren, P Nilsson, Ole Gredal, Jarl Hagglund, L O Ronnevi, Stefan L. MarklundAbstract:Four-hundred and fifty-one blood samples from Scandinavian patients with motor neuron disease were analysed for mutations in the CuZn-Superoxide Dismutase gene. Forty-one (9.6%) of the 427 patients with the amyotrophic lateral sclerosis (ALS) form of the disease were found to have a disease-associated mutation, and 14 of these patients were apparently sporadic cases. A mutation was found in 12 of the 51 families with recognized familial ALS. The five different mutations found (Ala4Val, Val14Gly, Asp76Tyr, Asp90Ala, Gly127insTGGG) have different genetic characteristics and are associated with very variable phenotypes spanning from rapidly progressing disease with only lower motor neuron signs to very slowly progressing disease with both the upper and lower motor neuron systems affected. The patients showed different sites of onset, though the progressive bulbar palsy form of the disease appears to be rare among patients with a CuZn-Superoxide Dismutase mutation. The progression of motor signs and symptoms followed the same basic pattern in patients with different mutations. Extra-motor system symptoms were frequent among patients with a CuZn-Superoxide Dismutase mutation. The results suggest that patients with mutations in the CuZn-Superoxide Dismutase gene constitute one disease entity. The Val14Gly and Asp76Tyr mutations have not been reported before, and the latter is the first mutation to be found in exon 3 of the CuZn-Superoxide Dismutase gene.
Joseph S Beckman - One of the best experts on this subject based on the ideXlab platform.
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liposome delivered Superoxide Dismutase prevents nitric oxide dependent motor neuron death induced by trophic factor withdrawal
Free Radical Biology and Medicine, 2000Co-Authors: Alvaro G Estevez, Nathan Spear, G J Richardson, John P Crow, Margaret M Tarpey, Yingxin Zhuang, Jacinda B Sampson, Luis Barbeito, Joseph S BeckmanAbstract:Inhibition of nitric oxide synthesis prevents rat embryonic motor neurons from undergoing apoptosis when initially cultured without brain-derived neurotrophic factor. Using an improved cell culture medium, we found that the partial withdrawal of trophic support even weeks after motor neurons had differentiated into a mature phenotype still induced apoptosis through a process dependent upon nitric oxide. However, nitric oxide itself was not directly toxic to motor neurons. To investigate whether intracellular Superoxide contributed to nitric oxide–dependent apoptosis, we developed a novel method using pH-sensitive liposomes to deliver Cu, Zn Superoxide Dismutase intracellularly into motor neurons. Intracellular Superoxide Dismutase prevented motor neuron apoptosis from trophic factor withdrawal, whereas empty liposomes, inactivated Superoxide Dismutase in liposomes or extracellular Superoxide Dismutase did not. Neither hydrogen peroxide nor nitrite added separately or in combination affected motor neuron survival. Our results suggest that a partial reduction in trophic support induced motor neuron apoptosis by a process requiring the endogenous production of both nitric oxide and Superoxide, irrespective of the extent of motor neuron maturation in culture.
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nitration and inactivation of manganese Superoxide Dismutase in chronic rejection of human renal allografts
Proceedings of the National Academy of Sciences of the United States of America, 1996Co-Authors: Lee Ann Macmillancrow, John P Crow, Joseph S Beckman, Jeffrey D Kerby, John A ThompsonAbstract:Inflammatory processes in chronic rejection remain a serious clinical problem in organ transplantation. Activated cellular infiltrate produces high levels of both Superoxide and nitric oxide. These reactive oxygen species interact to form peroxynitrite, a potent oxidant that can modify proteins to form 3-nitrotyrosine. We identified enhanced immunostaining for nitrotyrosine localized to tubular epithelium of chronically rejected human renal allografts. Western blot analysis of rejected tissue demonstrated that tyrosine nitration was restricted to a few specific polypeptides. Immunoprecipitation and amino acid sequencing techniques identified manganese Superoxide Dismutase, the major antioxidant enzyme in mitochondria, as one of the targets of tyrosine nitration. Total manganese Superoxide Dismutase protein was increased in rejected kidney, particularly in the tubular epithelium; however, enzymatic activity was significantly decreased. Exposure of recombinant human manganese Superoxide Dismutase to peroxynitrite resulted in a dose-dependent (IC50 = 10 microM) decrease in enzymatic activity and concomitant increase in tyrosine nitration. Collectively, these observations suggest a role for peroxynitrite during development and progression of chronic rejection in human renal allografts. In addition, inactivation of manganese Superoxide Dismutase by peroxynitrite may represent a general mechanism that progressively increases the production of peroxynitrite, leading to irreversible oxidative injury to mitochondria.
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kinetics of Superoxide Dismutase and iron catalyzed nitration of phenolics by peroxynitrite
Archives of Biochemistry and Biophysics, 1992Co-Authors: Joseph S Beckman, Ling Zhu, Mark Van Der Woerd, Craig R Smith, Jun Chen, Joseph G Harrison, James C Martin, Michael TsaiAbstract:Superoxide Dismutase and Fe3+EDTA catalyzed the nitration by peroxynitrite (ONOO-) of a wide range of phenolics including tyrosine in proteins. Nitration was not mediated by a free radical mechanism because hydroxyl radical scavengers did not reduce either Superoxide Dismutase or Fe3+EDTA-catalyzed nitration and nitrogen dioxide was not a significant product from either catalyst. Rather, metal ions appear to catalyze the heterolytic cleavage of peroxynitrite to form a nitronium-like species (NO2+). The calculated energy for separating peroxynitrous acid into hydroxide ion and nitronium ion is 13 kcal.mol-1 at pH 7.0. Fe3+EDTA catalyzed nitration with an activation energy of 12 kcal.mol-1 at a rate of 5700 M-1.s-1 at 37 degrees C and pH 7.5. The reaction rate of peroxynitrite with bovine Cu,Zn Superoxide Dismutase was 10(5) M-1.s-1 at low Superoxide Dismutase concentrations, but the rate of nitration became independent of Superoxide Dismutase concentration above 10 microM with only 9% of added peroxynitrite yielding nitrophenol. We propose that peroxynitrite anion is more stable in the cis conformation, whereas only a higher energy species in the trans conformation can fit in the active site of Cu,Zn Superoxide Dismutase. At high Superoxide Dismutase concentrations, phenolic nitration may be limited by the rate of isomerization from the cis to trans conformations of peroxynitrite as well as by competing pathways for peroxynitrite decomposition. In contrast, Fe3+EDTA appears to react directly with the cis anion, resulting in greater nitration yields.
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peroxynitrite mediated tyrosine nitration catalyzed by Superoxide Dismutase
Archives of Biochemistry and Biophysics, 1992Co-Authors: Ling Zhu, Jun Chen, James C Martin, Michael Tsai, Craig D Smith, Joseph S BeckmanAbstract:Abstract Peroxynitrite (ONOO − ), the reaction product of Superoxide (O 2 − ) and nitric oxide (NO), may be a major cytotoxic agent produced during inflammation, sepsis, and ischemia/reperfusion. Bovine Cu,Zn Superoxide Dismutase reacted with peroxynitrite to form a stable yellow protein-bound adduct identified as nitrotyrosine. The uv-visible spectrum of the peroxynitrite-modified Superoxide Dismutase was highly pH dependent, exhibiting a peak at 438 nm at alkaline pH that shifts to 356 nm at acidic pH. An equivalent uv-visible spectrum was obtained by Cu,Zn Superoxide Dismutase treated with tetranitromethane. The Raman spectrum of authentic nitrotyrosine was contained in the spectrum of peroxynitrite-modified Cu,Zn Superoxide Dismutase. The reaction was specific for peroxynitrite because no significant amounts of nitrotyrosine were formed with nitric oxide (NO), nitrogen dioxide (NO 2 ), nitrite (NO 2 − ), or nitrate (NO 3 − ). Removal of the copper from the Cu,Zn Superoxide Dismutase prevented formation of nitrotyrosine by peroxynitrite. The mechanism appears to involve peroxynitrite initially reacting with the active site copper to form an intermediate with the reactivity of nitronium ion (NO 2 + ), which then nitrates tyrosine on a second molecule of Superoxide Dismutase. In the absence of exogenous phenolics, the rate of nitration of tyrosine followed second-order kinetics with respect to Cu,Zn Superoxide Dismutase concentration, proceeding at a rate of 1.0 ± 0.1 m −1 · s −1 . Peroxynitrite-mediated nitration of tyrosine was also observed with the Mn and Fe Superoxide Dismutases as well as other copper-containing proteins.
J Kevin M D Ivey - One of the best experts on this subject based on the ideXlab platform.
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role of cellular Superoxide Dismutase against reactive oxygen metabolite induced cell damage in cultured rat hepatocytes
Hepatology, 1992Co-Authors: Yasuaki Ito, H Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, J Kevin M D IveyAbstract:Reactive oxygen metabolites have been reported to be important in the pathogenesis of ischemia/reperfusion-induced and alcohol-and druginduced liver injuries. We investigated the role of Superoxide Dismutase, cellular and extracellular, in preventing reactive oxygen metabolite–induced cytotoxicity in cultured rat hepatocytes. Cells were exposed to reactive oxygen metabolites enzymatically generated by hypoxanthine-xanthine oxidase. Cytotoxicity was quantified by measuring51Cr release from prelabeled cells and lactate dehydrogenase release. Reactive oxygen metabolites caused dose-dependent cytotoxicity. Good correlation was found between the values for51Cr and lactate dehydrogenase release. Reactive oxygen metabolite–induced cell damage was reduced by catalase but not by Superoxide Dismutase. Cellular Superoxide Dismutase and catalase activities were not increased after incubation with exogenous Superoxide Dismutase and catalase for up to 5 hr. Pretreatment with diethyldithiocarbamate inhibited cellular Superoxide Dismutase activity without inhibiting other antioxidants such as catalase, glutathione, glutathione reductase and glutathione peroxidase and sensitized cells to reactive oxygen metabolite–induced cytotoxicity. We conclude that hydrogen peroxide is an important mediator in hypoxanthine-xanthine oxidase–induced cell damage and that Superoxide Dismutase plays a critical role in cellular antioxidant defenses against hypoxanthine-xanthine oxidase–induced cytotoxicity in cultured rat hepatocytes in vitro. (HEPATOLOGY 1992;16:247–254.)
H Hiraishi - One of the best experts on this subject based on the ideXlab platform.
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role of cellular Superoxide Dismutase against reactive oxygen metabolite injury in cultured bovine aortic endothelial cells
Journal of Biological Chemistry, 1992Co-Authors: H Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, T Sugimoto, K J IveyAbstract:We examined the protective effect of cellular Superoxide Dismutase against extracellular hydrogen peroxide in cultured bovine aortic endothelial cells. 51Cr-labeled cells were exposed to hydrogen peroxide generated by glucose oxidase/glucose. Glucose oxidase caused a dose-dependent increase of 51Cr release. Pretreatment with diethyldithiocarbamate enhanced injury induced by glucose oxidase, corresponding with the degree of inhibition of endogenous Superoxide Dismutase activity. Inhibition of cellular Superoxide Dismutase by diethyldithiocarbamate was not associated either with alteration of other antioxidant defenses or with potentiation of nonoxidant injury. Enhanced glucose oxidase damage by diethyldithiocarbamate was prevented by chelating cellular iron. Inhibition of cellular xanthine oxidase neither prevented lysis by hydrogen peroxide nor diminished enhanced susceptibility by diethyldithiocarbamate. These results suggest that, in cultured endothelial cells: 1) cellular Superoxide is involved in mediating hydrogen peroxide-induced damage; 2) Superoxide, which would be generated upon exposure to excess hydrogen peroxide independently of cellular xanthine oxidase, promotes the Haber-Weiss reaction by initiating reduction of stored iron (Fe3+) to Fe2+; 3) cellular iron catalyzes the production of a more toxic species from these two oxygen metabolites; 4) cellular Superoxide Dismutase plays a critical role in preventing hydrogen peroxide damage by scavenging Superoxide and consequently by inhibiting the generation of the toxic species.
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role of cellular Superoxide Dismutase against reactive oxygen metabolite induced cell damage in cultured rat hepatocytes
Hepatology, 1992Co-Authors: Yasuaki Ito, H Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, J Kevin M D IveyAbstract:Reactive oxygen metabolites have been reported to be important in the pathogenesis of ischemia/reperfusion-induced and alcohol-and druginduced liver injuries. We investigated the role of Superoxide Dismutase, cellular and extracellular, in preventing reactive oxygen metabolite–induced cytotoxicity in cultured rat hepatocytes. Cells were exposed to reactive oxygen metabolites enzymatically generated by hypoxanthine-xanthine oxidase. Cytotoxicity was quantified by measuring51Cr release from prelabeled cells and lactate dehydrogenase release. Reactive oxygen metabolites caused dose-dependent cytotoxicity. Good correlation was found between the values for51Cr and lactate dehydrogenase release. Reactive oxygen metabolite–induced cell damage was reduced by catalase but not by Superoxide Dismutase. Cellular Superoxide Dismutase and catalase activities were not increased after incubation with exogenous Superoxide Dismutase and catalase for up to 5 hr. Pretreatment with diethyldithiocarbamate inhibited cellular Superoxide Dismutase activity without inhibiting other antioxidants such as catalase, glutathione, glutathione reductase and glutathione peroxidase and sensitized cells to reactive oxygen metabolite–induced cytotoxicity. We conclude that hydrogen peroxide is an important mediator in hypoxanthine-xanthine oxidase–induced cell damage and that Superoxide Dismutase plays a critical role in cellular antioxidant defenses against hypoxanthine-xanthine oxidase–induced cytotoxicity in cultured rat hepatocytes in vitro. (HEPATOLOGY 1992;16:247–254.)
Akira Terano - One of the best experts on this subject based on the ideXlab platform.
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role of cellular Superoxide Dismutase against reactive oxygen metabolite injury in cultured bovine aortic endothelial cells
Journal of Biological Chemistry, 1992Co-Authors: H Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, T Sugimoto, K J IveyAbstract:We examined the protective effect of cellular Superoxide Dismutase against extracellular hydrogen peroxide in cultured bovine aortic endothelial cells. 51Cr-labeled cells were exposed to hydrogen peroxide generated by glucose oxidase/glucose. Glucose oxidase caused a dose-dependent increase of 51Cr release. Pretreatment with diethyldithiocarbamate enhanced injury induced by glucose oxidase, corresponding with the degree of inhibition of endogenous Superoxide Dismutase activity. Inhibition of cellular Superoxide Dismutase by diethyldithiocarbamate was not associated either with alteration of other antioxidant defenses or with potentiation of nonoxidant injury. Enhanced glucose oxidase damage by diethyldithiocarbamate was prevented by chelating cellular iron. Inhibition of cellular xanthine oxidase neither prevented lysis by hydrogen peroxide nor diminished enhanced susceptibility by diethyldithiocarbamate. These results suggest that, in cultured endothelial cells: 1) cellular Superoxide is involved in mediating hydrogen peroxide-induced damage; 2) Superoxide, which would be generated upon exposure to excess hydrogen peroxide independently of cellular xanthine oxidase, promotes the Haber-Weiss reaction by initiating reduction of stored iron (Fe3+) to Fe2+; 3) cellular iron catalyzes the production of a more toxic species from these two oxygen metabolites; 4) cellular Superoxide Dismutase plays a critical role in preventing hydrogen peroxide damage by scavenging Superoxide and consequently by inhibiting the generation of the toxic species.
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role of cellular Superoxide Dismutase against reactive oxygen metabolite induced cell damage in cultured rat hepatocytes
Hepatology, 1992Co-Authors: Yasuaki Ito, H Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, J Kevin M D IveyAbstract:Reactive oxygen metabolites have been reported to be important in the pathogenesis of ischemia/reperfusion-induced and alcohol-and druginduced liver injuries. We investigated the role of Superoxide Dismutase, cellular and extracellular, in preventing reactive oxygen metabolite–induced cytotoxicity in cultured rat hepatocytes. Cells were exposed to reactive oxygen metabolites enzymatically generated by hypoxanthine-xanthine oxidase. Cytotoxicity was quantified by measuring51Cr release from prelabeled cells and lactate dehydrogenase release. Reactive oxygen metabolites caused dose-dependent cytotoxicity. Good correlation was found between the values for51Cr and lactate dehydrogenase release. Reactive oxygen metabolite–induced cell damage was reduced by catalase but not by Superoxide Dismutase. Cellular Superoxide Dismutase and catalase activities were not increased after incubation with exogenous Superoxide Dismutase and catalase for up to 5 hr. Pretreatment with diethyldithiocarbamate inhibited cellular Superoxide Dismutase activity without inhibiting other antioxidants such as catalase, glutathione, glutathione reductase and glutathione peroxidase and sensitized cells to reactive oxygen metabolite–induced cytotoxicity. We conclude that hydrogen peroxide is an important mediator in hypoxanthine-xanthine oxidase–induced cell damage and that Superoxide Dismutase plays a critical role in cellular antioxidant defenses against hypoxanthine-xanthine oxidase–induced cytotoxicity in cultured rat hepatocytes in vitro. (HEPATOLOGY 1992;16:247–254.)