TY - JOUR
T1 - Selenium modified mutagenicity and metabolism of benzo[a]pyrene in an S9-dependent system
AU - Teel, Robert W.
AU - Kain, Steven R.
N1 - Selenium added to the incubation mix containing rat-liver S9 modified both the metabolism and mutagenicity of benzo[a]pyrene (BaP) and several of its ...
PY - 1984/6
Y1 - 1984/6
N2 - Selenium added to the incubation mix containing rat-liver S9 modified both the metabolism and mutagenicity of benzo[a]pyrene (BaP) and several of its metabolites. Selenium (Na2SeO3) inhibited the S9-dependent mutagenic effects of BaP on Salmonella typhimurium strain TA100 as indicated by the number of histidine-dependent revertants counted. This inhibition was concentration-dependent over a range of 12.5 to 100 ppm. When used as the substrate the BaP metabolites 7,8-dihydrodiol, 9,10-dihydrodiol and 3-hydroxy also produced significantly fewer revertants in TA100 when selenium was included in the incubation mix. High-performance liquid chromatographic analysis of metabolites from S9-dependent metabolism of BaP indicated that selenium inhibited the formation of 3-hydroxy-BaP, 9,10-dihydrodiol, 7,8-dihydrodiol, 1,3- and 3,6-quinone. Eluting samples on an alumina column to isolate the conjugated metabolites showed that selenium caused 12% less binding to glucuronides, no significant differences in binding to sulfate esters or glutathione but the amount of unmetabolized BaP and unconjugated metabolites was increased by 48%. These results suggest that selenium inhibits S9-dependent BaP metabolism therefore reducing the mutagenic effects of this compound.
AB - Selenium added to the incubation mix containing rat-liver S9 modified both the metabolism and mutagenicity of benzo[a]pyrene (BaP) and several of its metabolites. Selenium (Na2SeO3) inhibited the S9-dependent mutagenic effects of BaP on Salmonella typhimurium strain TA100 as indicated by the number of histidine-dependent revertants counted. This inhibition was concentration-dependent over a range of 12.5 to 100 ppm. When used as the substrate the BaP metabolites 7,8-dihydrodiol, 9,10-dihydrodiol and 3-hydroxy also produced significantly fewer revertants in TA100 when selenium was included in the incubation mix. High-performance liquid chromatographic analysis of metabolites from S9-dependent metabolism of BaP indicated that selenium inhibited the formation of 3-hydroxy-BaP, 9,10-dihydrodiol, 7,8-dihydrodiol, 1,3- and 3,6-quinone. Eluting samples on an alumina column to isolate the conjugated metabolites showed that selenium caused 12% less binding to glucuronides, no significant differences in binding to sulfate esters or glutathione but the amount of unmetabolized BaP and unconjugated metabolites was increased by 48%. These results suggest that selenium inhibits S9-dependent BaP metabolism therefore reducing the mutagenic effects of this compound.
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U2 - 10.1016/0027-5107(84)90134-9
DO - 10.1016/0027-5107(84)90134-9
M3 - Article
C2 - 6328289
SN - 0027-5107
VL - 127
SP - 9
EP - 14
JO - Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis
JF - Mutation Research - Fundamental and Molecular Mechanisms of Mutagenesis
IS - 1
ER -