TY - JOUR
T1 - Generation of free radicals by Cr(IV) from lipid hydroperoxides and its inhibition by chelators
AU - Mao, Y.
AU - Zang, L.
AU - Shi, X.
PY - 1995
Y1 - 1995
N2 - The generation of free radicals by Cr(IV) from lipid hydroperoxides was investigated by ESR spin trapping. The spin trap used was 5,5-dimethyl-1-pyrroline N-oxide (DMPO). Reaction of Cr(VI) with ascorbate was used as a source of Cr(IV). Incubation of Cr(VI) with ascorbate generated Cr(IV) and Cr(V). Addition of cumene hydroperoxide generated DMPO/R adduct with an enhancement of Cr(V) signal. Addition of Mn(II), whose function is to remove Cr(IV), caused dose-dependent inhibition of DMPO/R formation. Similar results were obtained using t-butyl hydroperoxide. Metal ion chelators, deferoxamine, 1,10-phenanthroline and diethylenetriaminepentaacetic acid inhibited DMPO/R formation in the order of deferoxamine > 1,10-phenanthroline > diethylenetriaminepentaacetic acid. The results suggest the possible role of Cr(IV) and its mediated free radical generation from lipid hydroperoxides in the mechanism of Cr(VI) carcinogenesis.
AB - The generation of free radicals by Cr(IV) from lipid hydroperoxides was investigated by ESR spin trapping. The spin trap used was 5,5-dimethyl-1-pyrroline N-oxide (DMPO). Reaction of Cr(VI) with ascorbate was used as a source of Cr(IV). Incubation of Cr(VI) with ascorbate generated Cr(IV) and Cr(V). Addition of cumene hydroperoxide generated DMPO/R adduct with an enhancement of Cr(V) signal. Addition of Mn(II), whose function is to remove Cr(IV), caused dose-dependent inhibition of DMPO/R formation. Similar results were obtained using t-butyl hydroperoxide. Metal ion chelators, deferoxamine, 1,10-phenanthroline and diethylenetriaminepentaacetic acid inhibited DMPO/R formation in the order of deferoxamine > 1,10-phenanthroline > diethylenetriaminepentaacetic acid. The results suggest the possible role of Cr(IV) and its mediated free radical generation from lipid hydroperoxides in the mechanism of Cr(VI) carcinogenesis.
UR - http://www.scopus.com/inward/record.url?scp=0029550989&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029550989&partnerID=8YFLogxK
M3 - Article
C2 - 7663436
AN - SCOPUS:0029550989
SN - 1039-9712
VL - 36
SP - 327
EP - 337
JO - Biochemistry and Molecular Biology International
JF - Biochemistry and Molecular Biology International
IS - 2
ER -