Direct oxidation of polyunsaturated cis-parinaric fatty acid by phenoxyl radicals generated by peroxidase/H2O2 in model systems and in HL-60 cells.
Reactivity of phenoxyl radicals towards biomolecules (proteins, nucleic acids and lipids) is essential for antioxidant (protective) versus prooxidant (cytotoxic) effects of phenolic compounds (antioxidants, phytochemicals, environmental pollutants and toxic chemicals). The present study demonstrates for the first time that phenoxyl radicals formed by peroxidase/H2O2-catalyzed oxidation of phenol can directly oxidize a natural polyunsaturated fatty acid, cis-parinaric acid (PnA) both in model systems and in membrane phospholipids of HL-60 cells. Endogenous antioxidants-ascorbate and glutathione-can act as one-electron reductants of phenoxyl radicals and provide effective protection against phenoxyl radical-induced oxidation of PnA.
Department of Environmental and Occupational Health, University of Pittsburgh, PA 15238, USA.
V B
VB
Ritov
E V
EV
Menshikova
R
R
Goldman
V E
VE
Kagan
D000704:Analysis of Variance; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism*; D018922:HL-60 Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism / Q000633:toxicity; D008565:Membrane Proteins / Q000378:metabolism; D016877:Oxidants / Q000633:toxicity*; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000378:metabolism; D010636:Phenols / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D010743:Phospholipids / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism; D013237:Stereoisomerism
D005231:Fatty Acids, Unsaturated; D005456:Fluorescent Dyes; D008565:Membrane Proteins; D016877:Oxidants; D010636:Phenols; D010743:Phospholipids; D012709:Serum Albumin; D006861:Hydrogen Peroxide; D010544:Peroxidases; C013641:parinaric acid