Cobalt-Mediated Generation of Reactive Oxygen Species and Its Possible Mechanism

Details

• Personal Author:
  Castranova, Vincent ; Gannett PM ; Leonard, Stephanie ; Rojanasakul Y ; Schwegler-Berry D ; Shi X ; Vallyathan V
• Description:
  Electron spin resonance spin trapping was utilized to investigate free radical generation from cobalt (Co) mediated reactions using 5,5-dimethyl-1-pyrroline (DMPO) as a spin trap. A mixture of Co with water in the presence of DMPO generated 5,5-dimethylpyrroline-(2)-oxy(1) DMPOX, indicating the production of strong oxidants. Addition of superoxide dismutase (SOD) to the mixture produced hydroxyl radical (OH). Catalase eliminated the generation of this radical and metal chelators, such as desferoxamine, diethylenetriaminepentaacetic acid or 1,10-phenanthroline, decreased it. Addition of Fe(II) resulted in a several fold increase in the OH generation. UV and O2 consumption measurements showed that the reaction of Co with water consumed molecular oxygen and generated Co(II). Since reaction of Co(II) with H2O2 did not generate any significant amount of OH radicals, a Co(I) mediated Fenton-like reaction [Co(I) + H2O2-->Co(II) + OH + OH-] seems responsible for OH generation. H2O2 is produced from O2.- via dismutation, O2- is produced by one-electron reduction of molecular oxygen catalyzed by Co. Chelation of Co(II) by biological chelators, such as glutathione or beta-ananyl-3-methyl-L-histidine alters, its oxidation-reduction potential and makes Co(II) capable of generating OH via a Co(II)-mediated Fenton-like reaction [Co(II) + H2O2-->Co(III) + OH + OH-]. Thus, the reaction of Co with water, especially in the presence of biological chelators, glutathione, glycylglycylhistidine and beta-ananyl-3-methyl-L-histidine, is capable of generating a whole spectrum of reactive oxygen species, which may be responsible for Co-induced cell injury. [Description provided by NIOSH]
• Subjects:
  Chelating Agents Chemistry Chemistry, Analytic Metals Occupational Health Safety
• Keywords:
  Analytical-chemistry Analytical-processes Author Keywords: Cobalt Cell-damage Cell Injury Chelating-agents Cobalt-compounds Mechanism Metal-compounds Metal-oxides Oxidation Reactive Oxygen Species

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• ISSN:
  0162-0134
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  239-244
• Volume:
  70
• Issue:
  3
• NIOSHTIC Number:
  nn:20025482
• Citation:
  J Inorg Biochem 1998 Jul; 70(3-4):239-244
• Contact Point Address:
  Pathology and Physiology Research Branch, National Institute for Occupational Safety and Health, Morgantown, WV 26505
• Email:
  xas0@cdc.gov
• Federal Fiscal Year:
  1998
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Inorganic Biochemistry
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:3ac6682e7f72ca21090e2b1ff80d84f7b2c6c223b3d01dc53de9ca1bc78d5d193d7fd6089fd7b78c85a90d554a548e5cb4ce9e4dc3bd84f678eb5cc815cb820f
• Download URL:
  https://stacks.cdc.gov/view/cdc/196829/cdc_196829_DS1.pdf
• File Type:
  [PDF - 189.94 KB ]