Document Detail

Mn(III)-desferrioxamine superoxide dismutase-mimic: alternative modes of action.
MedLine Citation:
PMID:  1654823     Owner:  NLM     Status:  MEDLINE    
Various low-molecular-weight copper chelates have been synthesized to mimic superoxide dismutase (SOD) by catalyzing O2-. dismutation. However, in the presence of cellular proteins, such chelates dissociate and thereby lose their SOD-mimetic activity. In contrast, desferrioxamine-Mn(III) 1:1 chelate (DF-Mn), an SOD-mimic that affords protection from oxidative damage, reportedly is stable in the presence of serum albumin. DF-Mn, unlike SOD, is reported to permeate the membrane of at least one cell type and can protect cells by detoxifying intracellular O2-.. Recently DF-Mn was shown to protect hypoxic cells from H2O2-induced damage. Such results suggest that DF-Mn can protect cells from O2-.-independent damage by alternative mechanisms. This study examines such possibilities. To avoid O2-. participation in the damaging process, killing of monolayered V79 Chinese hamster cells was induced in a hypoxic environment by t-butyl hydroperoxide (t-BHP). Damage induced by t-BHP was inhibitable by DF-Mn. DF-Mn was also found to rapidly oxidize iron(II)-bound DNA. Additionally, once DF-Mn oxidizes Fe(II) or Cu(I), the DF moiety of DF-Mn dissociates and rapidly binds to Fe(III) or Cu(II). Without excluding the possibility that DF-Mn protects cells by facilitating the removal of O2-., the present results show that this SOD-mimic can confer protection from cytotoxic processes independent of O2-. or of O2-.-derived active species.
S M Hahn; C M Krishna; A Samuni; J B Mitchell; A Russo
Related Documents :
10226583 - Acrolein cytotoxicity and glutathione depletion in n-3 fatty acid sensitive- and resist...
11897553 - Oxidative processes in the brain and non-neuronal tissues as biomarkers of alzheimer's ...
2495753 - Effect of epidermal growth factor on ornithine decarboxylase activity in a431 cells.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Archives of biochemistry and biophysics     Volume:  288     ISSN:  0003-9861     ISO Abbreviation:  Arch. Biochem. Biophys.     Publication Date:  1991 Jul 
Date Detail:
Created Date:  1991-10-24     Completed Date:  1991-10-24     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  0372430     Medline TA:  Arch Biochem Biophys     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  215-9     Citation Subset:  IM    
Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Catalase / metabolism
Cell Hypoxia / drug effects
Cell Line
Cell Survival / drug effects
Copper / metabolism
DNA / metabolism
Deferoxamine / pharmacology*
Metals / metabolism
Organometallic Compounds / pharmacology
Superoxide Dismutase / pharmacology*
Superoxides / metabolism
Reg. No./Substance:
0/Metals; 0/Organometallic Compounds; 11062-77-4/Superoxides; 125892-49-1/manganese desferioxamine; 70-51-9/Deferoxamine; 7440-50-8/Copper; 9007-49-2/DNA; EC; EC Dismutase

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

Previous Document:  The binding of terbium ions to gelsolin reveals two classes of metal ion binding sites.
Next Document:  The role of xanthine oxidase in paraquat intoxication.