Generation of Free Radicals from Hydrogen Peroxide and Lipid Hydroperoxides in the Presence of Cr(III)

Xianglin Shi, N. S. Dalal, Kazimierz S. Kasprzak

Research output: Contribution to journalArticlepeer-review

92 Scopus citations

Abstract

Free radical generation from H2O2 and lipid hydroperoxides in the presence of Cr(III) was investigated by electron spin resonance (ESR) spin trapping methodology. Incubation of Cr(III) with H2O2 at physiological pH generated hydroxyl (·OH) radical, the yield of which reached saturation level in about 6 min. Deferoxamine reduced the ·OH radical yield by only about 20%, diethylenetriamine pentaacetic acid (DTPA) reduced it by about 70%, while cysteine, glutathione, and NADH exhibited no significant effect. The yield of ·OH radical formation also depended on the pH being 15 times higher at pH 10 than that at pH 7.2. At pH 3.0, ·OH radical generation became nondetectable, and addition of H2O2 to Cr(III) solution did not affect the intensity of the Cr(III) ESR signal while at pH 10, addition of H2O2 reduced the Cr(III) intensity by about 40%, showing that reaction of Cr(III) with H2O2 occurred only at higher pH. Incubation of Cr(III) with the model lipid hydroperoxides, cumene hydroperoxide and t-butyl hydroperoxide, generated lipid hydroperoxide-derived free radicals. Addition of deferoxamine or DTPA had a minor inhibitory effect on that generation. These results show that Cr(III) is capable of producing free radicals from H2O2 and lipid hydroperoxides, which may have significant implications regarding the mechanism of chromium-induced carcinogenesis.

Original languageEnglish
Pages (from-to)294-299
Number of pages6
JournalArchives of Biochemistry and Biophysics
Volume302
Issue number1
DOIs
StatePublished - 1993

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology

Fingerprint

Dive into the research topics of 'Generation of Free Radicals from Hydrogen Peroxide and Lipid Hydroperoxides in the Presence of Cr(III)'. Together they form a unique fingerprint.

Cite this