The role of reactive oxygen metabolites in lymphocyte-mediated cytolysis

1987 ◽  
Vol 87 (3) ◽  
pp. 473-481
Author(s):  
C.J. Bishop ◽  
C.M. Rzepczyk ◽  
D. Stenzel ◽  
K. Anderson
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Death ◽  
Xanthine Oxidase ◽  
Natural Killer ◽  
Reactive Oxygen ◽  
Tumour Cells ◽  
Reactive Oxygen Metabolites ◽  
Oxygen Metabolites

To examine the possible role of reactive oxygen metabolites in lymphocyte-mediated cytolysis, the morphology of cell death following the exposure of cells to reactive oxygen metabolites in vitro was compared with the morphology of cell-mediated killing in vitro of tumour cells by natural killer (NK) cells. Ultrastructural examination of human tumour cells that were dying following incubation for 60 min with the oxygen metabolite generating systems, xanthine-xanthine oxidase or t-butylhydroperoxide, showed that cell death in both instances was exclusively by necrosis. It was unclear which oxygen metabolites were involved in killing. Cell death was not decreased by the addition of superoxide dismutase, a scavenger of the superoxide anion, to the xanthine-xanthine oxidase mixture. Although the cells were not killed by incubation with 1 mM-hydrogen peroxide, the addition of catalase, a scavenger of hydrogen peroxide, to the xanthine-xanthine oxidase mixture significantly reduced cell death. The addition of scavengers for the hydroxyl radical to either the xanthine-xanthine oxidase mixture or t-butylhydroperoxide gave inconsistent protection. In contrast, tumour cell killing mediated by natural killer cells was by apoptosis, a morphologically distinct mode of cell death with a different basic mechanism, indicating that reactive oxygen metabolites are not directly involved in lymphocyte-mediated cytolysis.

Role of reactive oxygen metabolites in DNA damage and cell death in chemical hypoxic injury to LLC-PK1 cells

1996 ◽  
Vol 271 (1) ◽  
pp. F209-F215 ◽  
Author(s):  
H. Hagar ◽  
N. Ueda ◽  
S. V. Shah
Keyword(s):  
Dna Damage ◽  
Cell Death ◽  
Reactive Oxygen ◽  
Reactive Oxygen Metabolites ◽  
Strand Breaks ◽  
Hypoxic Injury ◽  
Chemical Hypoxia ◽  
Dna Strand ◽  
Oxygen Metabolites

Hypoxia is considered to result in a necrotic form of cell injury. We have recently demonstrated a role of endonuclease activation, generally considered a feature of apoptosis, to be almost entirely responsible for DNA damage in hypoxic injury to renal tubular epithelial cells. The role of reactive oxygen metabolites in endonuclease-induced DNA damage and cell death in chemical hypoxic injury has not been previously examined. LLC-PK1 cells exposed to chemical hypoxia with antimycin A resulted in enhanced generation of intracellular reactive oxygen species as measured by oxidation of a sensitive fluorescent probe, 2',7'-dichlorofluorescin diacetate. Superoxide dismutase, a scavenger of superoxide radical, significantly reduced the fluorescence induced by antimycin A and provided significant protection against chemical hypoxia-induced DNA strand breaks (as measured by the alkaline unwinding assay). Pyruvate, a scavenger of hydrogen peroxide, provided significant protection against chemical hypoxia-induced DNA strand breaks and DNA fragmentation (as measured by agarose gel electrophoresis). The interaction between superoxide anion and hydrogen peroxide in the presence of a metal catalyst leads to generation of other oxidant species such as hydroxyl radical. Hydroxyl radical scavengers, dimethylthiourea, salicylate, and sodium benzoate, and two metal chelators, deferoxamine and 1,10-phenanthroline, also provided marked protection against DNA strand breaks and DNA fragmentation. These scavengers of reactive oxygen metabolites and metal chelators provided significant protection against cell death as measured by trypan blue exclusion and lactate dehydrogenase release. Taken together, these data indicate that reactive oxygen species play an important role in the endonuclease activation and consequent DNA damage, as well as cell death in chemical hypoxic injury to renal tubular epithelial cells.

Circulating xanthine oxidase: potential mediator of ischemic injury

1990 ◽  
Vol 258 (4) ◽  
pp. G564-G570 ◽  
Author(s):  
Y. Yokoyama ◽  
J. S. Beckman ◽  
T. K. Beckman ◽  
J. K. Wheat ◽  
T. G. Cash ◽  
...  
Keyword(s):  
Xanthine Oxidase ◽  
Tissue Injury ◽  
Reactive Oxygen ◽  
Systemic Circulation ◽  
Reactive Oxygen Metabolites ◽  
Vascular Endothelial ◽  
Hepatic Ischemia ◽  
Oxygen Metabolites ◽  
Krebs Henseleit Buffer

Reactive oxygen metabolites generated from the enzyme xanthine oxidase (XO) play an important role in the pathogenesis of ischemia-induced tissue injury. The observation that intracellular proteins such as aspartate transaminase (AST) and alcohol dehydrogenase (ADH) are released from the ischemic liver during reperfusion led us to postulate that XO could be released into the systemic circulation. Livers from fasted rats were extirpated, perfused with oxygenated Krebs-Henseleit buffer, and subjected to 2 h ischemia followed by 2 h reperfusion. Reperfusion increased AST in the perfusate from 1 +/- 1 to 830 +/- 280 U/l, whereas ADH increased from 0.3 +/- 0.1 to 95 +/- 26 U/l. Concomitantly, xanthine dehydrogenase (XDH) + XO activity in the perfusate increased from 0 to 4.1 +/- 1.0 mU/ml. A 64% decrease in endogenous tissue XDH + XO activity paralleled release of XDH + XO. The XDH + XO activity predicted to appear in the circulation after hepatic ischemia was sufficient, when supplied with substrate, to produce severe vascular endothelial injury in vitro, even in the presence of serum or whole blood. These results suggest that massive quantities of XDH and XO are released into the circulation after hepatic ischemia and that the resulting reactive oxygen metabolites could produce widespread tissue injury.

Metabolism of extracellular adenine nucleotides by human endothelial cells exposed to reactive oxygen metabolites

1993 ◽  
Vol 264 (2) ◽  
pp. C282-C286 ◽  
Author(s):  
T. K. Aalto ◽  
K. O. Raivio
Keyword(s):  
Hydrogen Peroxide ◽  
Endothelial Cells ◽  
Xanthine Oxidase ◽  
Adenine Nucleotides ◽  
Ischemia Reperfusion ◽  
Reactive Oxygen ◽  
Extracellular Nucleotides ◽  
Reactive Oxygen Metabolites ◽  
Human Pathology ◽  
Oxygen Metabolites

Endothelial cells have ectonucleotidases that rapidly catabolize extracellular nucleotides. Our aim was to study whether the metabolism of extracellular nucleotides and adenosine are influenced by exposure of endothelial cells to reactive oxygen metabolites at concentrations relevant to human pathology. Human umbilical vein endothelial cells were incubated with hypoxanthine (100 microM) and xanthine oxidase (80 mU/ml), to generate superoxide, or with hydrogen peroxide (100 microM). The cells were then washed, and the metabolism of radioactive substrates was followed. After exposure to hypoxanthine-xanthine oxidase the half time of disappearance of [14C]ATP (5 microM) was prolonged from 9.9 +/- 5 to 28.3 +/- 15.6 min and that of [14C]AMP from 9.5 +/- 2.5 to 25.0 +/- 9.9 min. The conversion of extra- into intracellular nucleotides via adenosine was also decreased (mean for [14C]ATP 0.25 vs. 0.90 and for [14C]AMP, 0.075 vs. 0.75 nmol/10(6) cells in 30 min compared with parallel controls, respectively). Hydrogen peroxide or trypsin had no significant effect on the metabolism of extracellular adenine nucleotides and neither did a short (up to 15 min) exposure to the superoxide-generating system. The conversion of [14C]adenosine into intracellular nucleotides and hypoxanthine was not influenced by either hypoxanthine-xanthine oxidase or by hydrogen peroxide. We conclude that superoxide radicals inhibit the catabolism of extracellular adenine nucleotides by the ectonucleotidases of endothelial cells and may thus modify the pathophysiology of ischemia-reperfusion injury.

scholarly journals Antiglomerular basement membrane nephritis in beige mice. Deficiency of leukocytic neutral proteinases prevents the induction of albuminuria in the heterologous phase.

1989 ◽  
Vol 169 (4) ◽  
pp. 1435-1448 ◽  
Author(s):  
G Schrijver ◽  
J Schalkwijk ◽  
J C Robben ◽  
K J Assmann ◽  
R A Koene
Keyword(s):  
Basement Membrane ◽  
Reactive Oxygen ◽  
Cathepsin G ◽  
Reactive Oxygen Metabolites ◽  
Glomerular Lesions ◽  
And Control ◽  
Dose Dependent ◽  
Oxygen Metabolites

Antiglomerular basement membrane (GBM) nephritis with massive albuminuria can be induced in mice by injection of heterologous antibodies against mouse GBM. The albuminuria and the glomerular lesions in this model are not mediated by complement, but are dependent on the presence of polymorphonuclear granulocytes (PMN) in the glomeruli. Neutral serine proteinases and reactive oxygen metabolites produced by activated PMN have been implicated as agents contributing to tissue damage. We examined the role of leukocytic neutral proteinases by comparing the glomerular damage and albuminuria after injection of rabbit anti-mouse GBM antibodies in normal control mice (C57BL/6J, +/+) and in beige mice (C57BL/6J,bg/bg) in which PMN are deficient of the neutral proteinases elastase and cathepsin G. The dose-dependent albuminuria that occurred in control mice after injection of 1.4-22 mg of anti-GBM antibodies was not observed in beige mice, despite a comparable influx of PMNs in the glomeruli. By electron microscopy both strains showed a similar attachment of PMN to the denuded GBM together with swelling and necrosis of endothelial cells. Elastase activity of extracts from PMN of beige mice was only 10-15% of the activity of control mice. In vitro, GBM degradation by PMN extracts of beige mice was 70% lower than that seen in control experiments. PMNs of beige and control mice showed no differences in superoxide production. In addition, administration of scavengers of reactive oxygen metabolites, such as catalase and desferrioxamine, did not prevent the albuminuria in this model. These findings support the important contribution of leukocytic neutral proteinases to the induction of albuminuria in the acute phase of anti-GBM nephritis in the mouse.

Gentamicin enhanced production of hydrogen peroxide by renal cortical mitochondria

1987 ◽  
Vol 253 (4) ◽  
pp. C495-C499 ◽  
Author(s):  
P. D. Walker ◽  
S. V. Shah
Keyword(s):  
Hydrogen Peroxide ◽  
Mitochondrial Respiration ◽  
Critical Role ◽  
Reactive Oxygen ◽  
Reactive Oxygen Metabolites ◽  
Enhanced Production ◽  
Production Of Hydrogen ◽  
Hydrogen Peroxide Generation ◽  
Dose Dependent ◽  
Oxygen Metabolites

Agents that affect mitochondrial respiration have been shown to enhance the generation of reactive oxygen metabolites. On the basis of the well-demonstrated ability of gentamicin to alter mitochondrial respiration (stimulation of state 4 and inhibition of state 3), it was postulated that gentamicin may enhance the generation of reactive oxygen metabolites by renal cortical mitochondria. The aim of this study was to examine the effect of gentamicin on the production of hydrogen peroxide (measured as the decrease in scopoletin fluorescence) in rat renal cortical mitochondria. The hydrogen peroxide generation by mitochondria was enhanced from 0.17 +/- 0.02 nmol . mg-1 . min-1 (n = 14) in the absence of gentamicin to 6.21 +/- 0.67 nmol . mg-1 . min-1 (n = 14) in the presence of 4 mM gentamicin. This response was dose dependent with a significant increase observed at even the lowest concentration of gentamicin tested, 0.01 mM. Production of hydrogen peroxide was not increased when gentamicin was added to incubation media in which mitochondria or substrate was omitted or heat-inactivated mitochondria were used. The gentamicin-induced change in fluorescence was completely inhibited by catalase (but not by heat-inactivated catalase), indicating that the decrease in fluorescence was due to hydrogen peroxide. Thus this study demonstrates that gentamicin enhances the production of hydrogen peroxide by mitochondria. Because of their well-documented cytotoxicity, reactive oxygen metabolites may play a critical role in gentamicin nephrotoxicity.

Effect of Reactive Oxygen Metabolites on Endothelial Permeability: Role of Nitric Oxide and Iron

1999 ◽  
Vol 6 (2) ◽  
pp. 107-116 ◽  
Author(s):  
NAOTSUKA OKAYAMA ◽  
MATTHEW B. GRISHAM ◽  
CHRISTOPHER G. KEVIL ◽  
LOIS ANN EPPIHIMER ◽  
DAVID A. WINK ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Permeability ◽  
Reactive Oxygen ◽  
Reactive Oxygen Metabolites ◽  
Oxygen Metabolites

In vitro effects of reactive oxygen metabolites, with and without flunixin meglumine, on equine colonic mucosa

2007 ◽  
Vol 68 (3) ◽  
pp. 305-312 ◽  
Author(s):  
Olivia J. Inoue ◽  
David E. Freeman ◽  
Matthew A. Wallig ◽  
Robert B. Clarkson
Keyword(s):  
Colonic Mucosa ◽  
Reactive Oxygen ◽  
Reactive Oxygen Metabolites ◽  
Flunixin Meglumine ◽  
In Vitro Effects ◽  
Oxygen Metabolites
Sign in / Sign up

Export Citation Format

Share Document