Construction of Cu-Zn superoxide dismutase deletion mutants of Brucella abortus: analysis of survival in vitro in epithelial and phagocytic cells and in vivo in mice.

SummaryIn the course of studying the effects on platelets of the oxidant species superoxide (O- 2), Of was generated by the interaction of xanthine oxidase plus xanthine. Surprisingly, gel-filtered platelets, when exposed to xanthine oxidase in the absence of xanthine substrate, were found to generate superoxide (O- 2), as determined by the reduction of added cytochrome c and by the inhibition of this reduction in the presence of superoxide dismutase.In addition to generating Of, the xanthine oxidase-treated platelets display both aggregation and evidence of the release reaction. This xanthine oxidase induced aggreagtion is not inhibited by the addition of either superoxide dismutase or cytochrome c, suggesting that it is due to either a further metabolite of O- 2, or that O- 2 itself exerts no important direct effect on platelet function under these experimental conditions. The ability of Of to modulate platelet reactions in vivo or in vitro remains in doubt, and xanthine oxidase is an unsuitable source of O- 2 in platelet studies because of its own effects on platelets.

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Stable Mn(III) porphyrins mimic superoxide dismutase in vitro and substitute for it in vivo.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)31540-5 ◽

1994 ◽

Vol 269 (38) ◽

pp. 23471-23476 ◽

Cited By ~ 10

Author(s):

K.M. Faulkner ◽

S.I. Liochev ◽

I. Fridovich

Keyword(s):

Superoxide Dismutase

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Abstract 34: Endogenous Superoxide Dismutase Protects From Impaired Generation of Activated Protein C and Enhanced Susceptibility to Experimental Thrombosis in Mice

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.34.suppl_1.34 ◽

2014 ◽

Vol 34 (suppl_1) ◽

Author(s):

Sanjana Dayal ◽

Sean X Gu ◽

Katinan M Wilson ◽

Ryan Hutchins ◽

Steven R Lentz

Keyword(s):

Superoxide Dismutase ◽

Protein C ◽

Activated Protein C ◽

Vena Cava ◽

Oxidative Modification ◽

Mrna Levels ◽

Endothelial Protein C Receptor ◽

Experimental Thrombosis

In vitro studies have suggested that reactive oxygen species such as superoxide can produce prothrombotic effects, including enhanced platelet activation, increased tissue factor (TF) expression, and an oxidative modification in thrombomodulin impairing its capacity to enhance the generation of activated protein C (APC) by thrombin. It is not known, however, if elevated levels of superoxide accelerate susceptibility to experimental thrombosis in vivo . We used mice genetically deficient in superoxide dismutase-1 (SOD1, an antioxidant enzyme that dismutates superoxide to hydrogen peroxide), to test the hypothesis that lack of SOD1 enhances susceptibility to thrombosis. Susceptibility to carotid artery thrombosis in a photochemical injury model demonstrated that Sod1-/- mice formed stable occlusions significantly faster than Sod1+/+ mice (P<0.05). In an inferior vena cava (IVC) stasis model Sod1- /- mice developed significantly larger thrombi 48 hours after IVC ligation (P<0.05 vs. Sod1+/+ mice). After activation with thrombin (0.5 U/ml) or convulxin (200 ng/ml), no differences in surface expression of P-selectin or binding of fibrinogen were observed between platelets from Sod1-/- and Sod1+/+ mice. The expression of TF mRNA in lung measured by real time qPCR showed similar levels in Sod1-/- and Sod1 +/+ mice. However, the activation of exogenous protein C by thrombin in lung homogenates was decreased in Sod1 -/- mice (P<0.05 vs. Sod1 +/+ mice). Further, in vivo generation of activated protein C in response to thrombin (40 U/Kg) infusion was significantly lower in Sod1-/- mice (P<0.05 vs. Sod1+/+ mice). No differences in mRNA levels for thrombomodulin or endothelial protein C receptor were detected in Sod1 -/- mice vs. Sod1 +/+ mice, suggesting that altered generation of activated protein C in Sod1-/- mice may be related to a direct oxidative effect on thrombomodulin. In accordance, thrombomodulin treated with xanthine/hypoxanthine showed 40% loss of ability to activate protein C that was overcome by addition of SOD and catalase (P<0.05). We conclude that endogenous SOD1 in mice protects from impaired generation of activated protein C and accelerated thrombosis.

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Conjugates of Superoxide Dismutase 1 with Amphiphilic Poly(2-oxazoline) Block Copolymers for Enhanced Brain Delivery: Synthesis, Characterization and Evaluation in Vitro and in Vivo

Molecular Pharmaceutics ◽

10.1021/mp300496x ◽

2012 ◽

Vol 10 (1) ◽

pp. 360-377 ◽

Cited By ~ 53

Author(s):

Jing Tong ◽

Xiang Yi ◽

Robert Luxenhofer ◽

William A. Banks ◽

Rainer Jordan ◽

...

Keyword(s):

Superoxide Dismutase ◽

Block Copolymers ◽

Brain Delivery ◽

Superoxide Dismutase 1

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Cigarette smoking, emphysema, and damage to alpha 1-proteinase inhibitor

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1994.266.6.l593 ◽

1994 ◽

Vol 266 (6) ◽

pp. L593-L611 ◽

Cited By ~ 13

Author(s):

M. D. Evans ◽

W. A. Pryor

Keyword(s):

Cigarette Smoke ◽

Proteinase Inhibitor ◽

Inflammatory Cells ◽

Lavage Fluid ◽

Lung Lavage ◽

Tissue Destruction ◽

Phagocytic Cells ◽

Lung Fluid

The proteinase-antiproteinase theory for the pathogenesis of emphysema proposes that the connective tissue destruction associated with emphysema arises from excessive proteinase activity in the lower respiratory tract. For this reason, the relative activities of neutrophil elastase and alpha 1-proteinase inhibitor (alpha 1-PI) are considered important. Most emphysema is observed in smokers; therefore, alpha 1-PI has been studied as a target for smoke-induced damage. Damage to alpha 1-PI in lung fluid could occur by several mechanisms involving species delivered to the lung by cigarette smoke and/or stimulated inflammatory cells. Oxidative damage to alpha 1-PI has received particular attention, since both cigarette smoke and inflammatory cells are rich sources of oxidants. In this article we review almost two decades of research on mechanistic studies of damage to alpha 1-PI by cigarette smoke and phagocytic cells in vitro, studies emphasizing the importance of elastinolytic activity in the pathogenesis of emphysema in vivo and studies of human lung lavage fluid to detect defects in alpha 1-PI at the molecular and functional levels.

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Evaluation of Protection Afforded by Brucella abortus and Brucella melitensis Unmarked Deletion Mutants Exhibiting Different Rates of Clearance in BALB/c Mice

Infection and Immunity ◽

10.1128/iai.01787-05 ◽

2006 ◽

Vol 74 (7) ◽

pp. 4048-4057 ◽

Cited By ~ 59

Author(s):

M. M. Kahl-McDonagh ◽

T. A. Ficht

Keyword(s):

Mouse Model ◽

Brucella Abortus ◽

Protective Immunity ◽

Brucella Melitensis ◽

Deletion Mutants ◽

Heterologous Challenge ◽

Current Vaccine ◽

Protection Against Infection ◽

Ideal Vaccine

ABSTRACT Research for novel Brucella vaccines has focused upon the development of live vaccine strains, which have proven more efficacious than killed or subunit vaccines. In an effort to develop improved vaccines, signature-tagged mutant banks were screened to identify mutants attenuated for survival. Mutants selected from these screens exhibited various degrees of attenuation characterized by the rate of clearance, ranging from a failure to grow in macrophages after 24 h of infection to a failure to persist in the mouse model beyond 8 weeks. Ideal vaccine candidates should be safe to the host, while evoking protective immunity. In the present work, we constructed unmarked deletion mutants of three gene candidates, manBA, virB2, and asp24, in both Brucella abortus and Brucella melitensis. The Δasp24 mutants, which persist for extended periods in vivo, are superior to current vaccine strains and to other deletion strains tested in the mouse model against homologous challenge infection after 12, 16, and 20 weeks postvaccination. The Δasp24 mutants also display superior protection compared to ΔmanBA and ΔvirB2 mutants against heterologous challenge in mice. From this study, a direct association between protection against infection and cytokine response was not apparent between all vaccine groups and, therefore, correlates of protective immunity will need to be considered further. A distinct correlation between persistence of the vaccine strain and protection against infection was corroborated.

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Mycobacterium tuberculosis Alters the Metalloprotease Activity of the COP9 Signalosome

mBio ◽

10.1128/mbio.01278-14 ◽

2014 ◽

Vol 5 (4) ◽

Cited By ~ 7

Author(s):

Lia Danelishvili ◽

Lmar Babrak ◽

Sasha J. Rose ◽

Jamie Everman ◽

Luiz E. Bermudez

Keyword(s):

Mycobacterium Tuberculosis ◽

Cop9 Signalosome ◽

Virulence Determinants ◽

Bacterial Survival ◽

Phagocytic Cells ◽

Content Type ◽

Metalloprotease Activity ◽

Macrophage Protein

ABSTRACT Inhibition of apoptotic death of macrophages by Mycobacterium tuberculosis represents an important mechanism of virulence that results in pathogen survival both in vitro and in vivo. To identify M. tuberculosis virulence determinants involved in the modulation of apoptosis, we previously screened a transposon bank of mutants in human macrophages, and an M. tuberculosis clone with a nonfunctional Rv3354 gene was identified as incompetent to suppress apoptosis. Here, we show that the Rv3354 gene encodes a protein kinase that is secreted within mononuclear phagocytic cells and is required for M. tuberculosis virulence. The Rv3354 effector targets the metalloprotease (JAMM) domain within subunit 5 of the COP9 signalosome (CSN5), resulting in suppression of apoptosis and in the destabilization of CSN function and regulatory cullin-RING ubiquitin E3 enzymatic activity. Our observation suggests that alteration of the metalloprotease activity of CSN by Rv3354 possibly prevents the ubiquitin-dependent proteolysis of M. tuberculosis-secreted proteins. IMPORTANCE Macrophage protein degradation is regulated by a protein complex called a signalosome. One of the signalosomes associated with activation of ubiquitin and protein labeling for degradation was found to interact with a secreted protein from M. tuberculosis, which binds to the complex and inactivates it. The interference with the ability to inactivate bacterial proteins secreted in the phagocyte cytosol may have crucial importance for bacterial survival within the phagocyte.

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The activity of superoxide-dismutase in animal cell culture CHO-K1 after treatment with fullerenol and mytomicine C

Hemijska industrija ◽

10.2298/hemind0903143b ◽

2009 ◽

Vol 63 (3) ◽

pp. 143-149 ◽

Cited By ~ 1

Author(s):

Visnja Bogdanovic ◽

Marija Slavic ◽

Jasminka Mrdjanovic ◽

Slavica Solajic ◽

Aleksandar Djordjevic

Keyword(s):

Superoxide Dismutase ◽

Mammalian Cells ◽

Animal Cell ◽

Water Soluble ◽

Cytotoxic Agents ◽

Antioxidant Defenses ◽

Free Radical Scavengers ◽

Sod Activity

Eukaryotic cell survives in predominantly reduced conditions. Homeostasis of cellular redox system is an imperative of cell surviving and its normal metabolism. ROS are well recognized for playing a dual role as both deleterious and beneficial species, since they can be either harmful or beneficial to living systems. These species are mutagenic compounds known to lead to DNA damage, favor cell transformation, and contribute to the development of a variety of malignant diseases. All the effects of oxidants are influenced by the cellular antioxidant defenses. This multilayer system consists of low molecular weight components and several antioxidant enzymes. Superoxide dismutases (SODs) are the only enzymes dismuting superoxide radicals. Mitomycin C, a cross-linking agent, demonstrated genotoxicity in all in vitro and in vivo test systems in mammalian cells and animals. Water-soluble fullerenes are well known as cytotoxic agents for many cell lines in vitro. At the other side, fullerenols are good free radical scavengers and antioxidants both in vitro and in vivo. This paper investigates the effects of fullerenol on survival and fullerenol/ /mytomicine (MMC) treatment on superoxide-dismutase (SOD) activity in CHO-K1 cells. Samples were treated 3 and 24 h with fullerenol (C60(OH)24) at concentration range 0.01-0.5 mg/mL and survival was monitored with dye exclusion test (DET). The activity of total SOD was estimated in samples treated with chosen concentrations of fullerenol and MMC (0.5 and 0.1 mg/mL) after 3 and 24 h of cell incubation. Increasing of C60(OH)24 concentration leads to decreasing of percent of surviving cells 3 and 24 h after incubation. The activity of total SOD enhanced with higher concentration of fullerenol, while decreased in the highest concentration at both experimental points. In samples treated with MMC, as well as in samples treated with fullerenol (0.0625 mg/mL) + MMC was noticed boost in total SOD activity in comparison with controls. Treatment with fullerenol decreased SOD activity in rest of samples treated with MMC. Decreased activity of superoxide-dismutase in almost all samples treated with fullerenol and MMC might be contributed to antioxidative properties of fullerenol. Increased enzyme level at concentration of 0.0625 mg/mL may be due to its prooxidative activity.

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Comparison of defence responses to Botrytis cinerea infection in tomato plants propagated in vitro and grown in vivo

Acta Agrobotanica ◽

10.5586/aa.1996.012 ◽

2013 ◽

Vol 49 (1-2) ◽

pp. 115-121 ◽

Cited By ~ 1

Author(s):

Jacek Patykowski ◽

Elżbieta Kuźniak ◽

Henryk Urbaniak

Keyword(s):

Superoxide Dismutase ◽

Botrytis Cinerea ◽

Ascorbate Peroxidase ◽

Guaiacol Peroxidase ◽

Activity Increase ◽

Tomato Plants ◽

Defence Responses ◽

Defence Reactions

Defence reactions: O2 - generation, superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase activities after B. cinerea infection in tomato plants propagated in vitro and grown in vivo have been compared. Infection resulted in rapid O2 - generation. Superoxide dismutase activity increase was slower than O2 - response. In plants propagated in vitro catalase and guaiacol peroxidase activities after infection were induced less strongly than in plants grown in vivo. K2HPO4 pretreatment of plants grown in vitro enhanced significantly the activities of catalase and guaiacol peroxidase after infection. Slight restriction of B. cinerea infection development in in vitro propagated plants pretreated with K2HP04 was observed.

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Effect of hepatocyte-stimulating factor and glucocorticoids on plasma fibronectin levels

Biochemical Journal ◽

10.1042/bj2380365 ◽

1986 ◽

Vol 238 (2) ◽

pp. 365-371 ◽

Cited By ~ 43

Author(s):

D L Amrani ◽

D Mauzy-Melitz ◽

M W Mosesson

Keyword(s):

Acute Phase Protein ◽

Plasma Fibronectin ◽

Phagocytic Cells ◽

Serum Samples ◽

Exclusion Chromatography ◽

A Minor ◽

Two Peaks ◽

Stimulating Factor

We evaluated the effects of hepatocyte-stimulating factor (HSF) and a glucocorticoid (dexamethasone) on changes in the levels, in vivo and in vitro, of plasma fibronectin (Fn), a glycoprotein that is synthesized and secreted by hepatocytes. In turpentine-treated chickens, plasma levels of Fn, which peaked at 48 h (whereas fibrinogen levels were maximum at 72 h) rose 200-250% over basal levels, whereas albumin levels decreased by 20-40%. Corticosterone levels in serum samples taken between 5 and 48 h after injection revealed a 124% increase in hormone levels at 24 h in turpentine-treated chickens. We also showed that circulating HSF levels were maximal 8 to 12 h after injection and that HSF activity, as assessed by molecular-exclusion chromatography, was eluted in the 30-45 kDa range. Addition of either serum-derived HSF or dexamethasone (2 nM) to chick hepatocyte cultures resulted in a 130-150% increase in secreted Fn as well as in fibrinogen. When HSF and dexamethasone were added together, a 360-489% increase in the secreted levels of both proteins was found. Chicken mononuclear phagocytic cells treated with lipopolysaccharide secreted an HSF activity that was eluted in two peaks, a minor peak at approximately 70 kDa and a major peak in the 25-40 kDa range. Addition of mononuclear-cell-derived HSF resulted in a greater increase in Fn levels than did the addition of serum HSF. These findings indicate that Fn, like fibrinogen, is an acute-phase protein, the production of which, at least in chickens, is stimulated by HSF and glucocorticoids in an additive manner.

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