Document Detail

H2O2 release from human granulocytes during phagocytosis. Relationship to superoxide anion formation and cellular catabolism of H2O2: studies with normal and cytochalasin B-treated cells.
MedLine Citation:
PMID:  199619     Owner:  NLM     Status:  MEDLINE    
Normal and cytochalasin B-treated human granulocytes have been studied to determine some of the interrelationships between phagocytosis-induced respiration and superoxide and hydrogen peroxide formation and release into the extracellular medium by intact cells. By using the scopoletin fluorescent assay to continuously monitor extracellular hydrogen peroxide concentrations during contact of cells with opsonized staphylococci, it was demonstrated that the superoxide scavengers ferricytochrome c and nitroblue tetrazolium significantly reduced the amount of H(2)O(2) released with time from normal cells but did not abolish it. This inhibitory effect was reversed by the simultaneous addition of superoxide dismutase (SOD), whereas the addition of SOD alone increased the amount of detectable H(2)O(2) in the medium. The addition of sodium azide markedly inhibited myeloperoxidase-H(2)O(2)-dependent protein iodination and more than doubled H(2)O(2) release, including the residual amount remaining after exposure of the cells to ferricytochrome c, suggesting its origin from an intracellular pool shared by several pathways for H(2)O(2) catabolism. When cells were pretreated with cytochalasin B and opsonized bacteria added, reduced oxygen consumption was observed, but this was in parallel to a reduction in specific binding of organisms to the cells when compared to normal. Under the influence of inhibited phagosome formation by cytochalasin B, the cells released an increased amount of superoxide and peroxide into the extracellular medium relative to oxygen consumption, and all detectable peroxide release could be inhibited by the addition of ferricytochrome c. Decreased H(2)O(2) production in the presence of this compound could not be ascribed to diminished bacterial binding, decreased oxidase activity, or increased H(2)O(2) catabolism and was reversed by the simultaneous addition of SOD. Furthermore, SOD and ferricytochrome c had similar effects on another H(2)O(2)-dependent reaction, protein iodination, in both normal and cytochalasin B cells. When oxygen consumption, O(2.) (-), and H(2)O(2) release were compared in the presence of azide under identical incubation conditions, the molar relationships for normal cells were 1.00:0.34:0.51 and for cytochalasin B-treated cells 1.00:0.99:0.40, respectively. Nonopsonized, or opsonized but disrupted, bacteria did not stimulate any of these metabolic functions. The results indicate that with normal cells approximately 50% of H(2)O(2) released during phagocytosis is derived directly from O(2.) (-) by dismutation, the remainder appearing from an (intra)cellular source shared by azide-inhibitable heme enzymes. With cytochalasin B treatment the evidence is consistent with the derivation of all H(2)O(2) from an O(2.) (-) precursor which is released from the cell surface. Furthermore, when activated by phagocytic particle binding, the neutrophil O(2.) (-) generating system appears to make more of this compound than can be accounted for by dismutation to H(2)O(2). This establishes conditions for the direct participation of both compounds in the microbicidal and cytocidal activity of these cells.
R K Root; J A Metcalf
Related Documents :
8033899 - Generation of reactive-oxygen species induced by electropermeabilization of chinese ham...
9337489 - Membrane-linked systems preventing superoxide formation.
18723529 - Hydrogen sulfide and oxygen sensing: implications in cardiorespiratory control.
11351079 - Enzymes that scavenge reactive oxygen species are down-regulated prior to gibberellic a...
19471969 - Identification and characterization of demethylase jmjd1a as a gene upregulated in the ...
19846259 - Do monoamine-synthesizing cells constitute a complex network of oxygen sensors?
23267139 - The nanoparticulate quillaja saponin bbe is selectively active towards renal cell carci...
23311359 - Age-structured cell population model to study the influence of growth factors on cell c...
8287449 - Cytotoxic effects of vascular smooth muscle cells of the chimeric toxin, heparin bindin...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of clinical investigation     Volume:  60     ISSN:  0021-9738     ISO Abbreviation:  J. Clin. Invest.     Publication Date:  1977 Dec 
Date Detail:
Created Date:  1977-12-29     Completed Date:  1977-12-29     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  7802877     Medline TA:  J Clin Invest     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1266-79     Citation Subset:  AIM; IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Azides / pharmacology
Cytochalasin B / pharmacology*
Cytochrome c Group / pharmacology
Granulocytes / metabolism*
Horseradish Peroxidase / diagnostic use
Hydrogen Peroxide / metabolism*
Leukocytes / metabolism*
Nitroblue Tetrazolium / pharmacology
Scopoletin / diagnostic use
Superoxide Dismutase / pharmacology
Superoxides / biosynthesis
Reg. No./Substance:
0/Azides; 0/Cytochrome c Group; 11062-77-4/Superoxides; 14930-96-2/Cytochalasin B; 298-83-9/Nitroblue Tetrazolium; 7722-84-1/Hydrogen Peroxide; 92-61-5/Scopoletin; EC 1.11.1.-/Horseradish Peroxidase; EC Dismutase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Neurogenic coronary vasoconstrictor effects of digitalis during acute global ischemia in dogs.
Next Document:  Vasopressin-stimulated prostaglandin E biosynthesis in the toad urinary bladder. Effect of water flo...