Direct oxidation of polyunsaturated cis-parinaric fatty acid by phenoxyl radicals generated by peroxidase/H2O2 in model systems and in HL-60 cells

Toxicol Lett. 1996 Oct;87(2-3):121-9. doi: 10.1016/0378-4274(96)03767-8.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Cells, Cultured
  • Chromatography, High Pressure Liquid
  • Fatty Acids, Unsaturated / chemistry
  • Fatty Acids, Unsaturated / metabolism*
  • Fluorescent Dyes / chemistry
  • Fluorescent Dyes / metabolism*
  • HL-60 Cells / cytology*
  • HL-60 Cells / drug effects
  • HL-60 Cells / metabolism
  • Humans
  • Hydrogen Peroxide / metabolism
  • Hydrogen Peroxide / toxicity
  • Membrane Proteins / metabolism
  • Oxidants / toxicity*
  • Oxidation-Reduction
  • Peroxidases / metabolism
  • Phenols / chemistry
  • Phenols / metabolism
  • Phenols / toxicity
  • Phospholipids / metabolism*
  • Serum Albumin / metabolism
  • Stereoisomerism

Substances

  • Fatty Acids, Unsaturated
  • Fluorescent Dyes
  • Membrane Proteins
  • Oxidants
  • Phenols
  • Phospholipids
  • Serum Albumin
  • Hydrogen Peroxide
  • Peroxidases
  • parinaric acid