Superoxide-dependent formation of hydroxyl radicals and lipid peroxidation in the presence of iron salts. Detection of 'catalytic' iron and anti-oxidant activity in extracellular fluids.
Synovial fluid from rheumatoid patients and normal cerebrospinal fluid contains micromolar concentrations of non-protein-bound iron salts that can promote lipid peroxidation and also the superoxide-dependent formation of hydroxyl radicals from hydrogen peroxide. These iron catalysts of oxygen radical reactions cannot be detected by conventional assays unless interfering high-molecular-weight substances, probably proteins, are removed by ultrafiltration or inactivated by exposure to low pH values. The bleomycin assay for ;catalytic' iron [Gutteridge, Rowley & Halliwell (1981) Biochem. J.199, 263-265] does not suffer from these artifacts.
D000818:Animals; D001921:Brain / Q000187:drug effects; D002417:Cattle; D005609:Free Radicals; D006801:Humans; D007501:Iron / Q000032:analysis / Q000378:metabolism* / Q000494:pharmacology; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis; D008081:Liposomes / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D013481:Superoxides / Q000032:analysis / Q000378:metabolism*; D013582:Synovial Fluid / Q000032:analysis
D005609:Free Radicals; D008055:Lipids; D008081:Liposomes; D013481:Superoxides; D007501:Iron; D010100:Oxygen