Detection of the major DNA adducts of benzo[j]fluoranthene in mouse skin: Nonclassical dihydrodiol epoxides

Abstract

Studies have demonstrated that the metabolic activation of benzo[j]fluoranthene (B[j]F) to a genotoxic agent proceeds through the formation of either the trans-4,5-dihydrodiol (B[j]F-4,5-diol) or the trans-9,10-dihydrodiol (B[j]F-9,10-diol) metabolite of B[j]F. Using 32P-postlabeling analysis, the profiles of DNA adducts formed in vivo in mouse skin from B[j]F-4,5-diol and B[j]F-9,10-diol were obtained to establish the contribution of each of these dihydrodiols to the formation of B[j]F-DNA adducts in vivo. B[j]F, B[j]F-4,5-diol and B[j]F-9,10-diol were applied to the shaved backs of mice (100 micrograms/mouse), and DNA adducts were isolated and separated using multidimensional TLC and reverse-phase HPLC. The greatest level of adducts was observed with B[j]F-4,5-diol, which resulted in the formation of 383 pmol of DNA adducts/mg of DNA. This level of DNA modification was more than 2 orders of magnitude greater than that observed with B[j]F or B[j]F-9,10-diol. The major adducts detected from the application of B[j]F-4,5-diol to mouse skin in vivo had chromatographic properties similar to those of the major adducts detected with B[j]F. In contrast, the major DNA adducts detected with B[j]F-9,10-diol had chromatographic properties distinctly different than the adducts formed from either B[j]F or B[j]F-4,5-diol. DNA adducts formed from the syn and anti isomers of the 4,5-dihydrodiol 6,6a-epoxide and the 9,10-dihydrodiol 11,12-epoxide of B[j]F were also evaluated. Each dihydrodiol epoxide derivative was reacted with calf thymus DNA in vitro and applied to mouse skin in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

The Gulf Oil Spill

“…Benzo[j]fluoranthene, benzo[j]fluoranthene-4,5-diol, and benzo[j]fluoranthene-9,10-diol were applied to the shaved backs of CD-l mice and the DNA adducts were isolated and separated using multidimensional thin-layer chromatography (TLC) and reverse-phase high performance liquid chromatography (HPLC) (Weyand et al 1993a). The highest level of adducts was observed with benzohlfluoranthene-4,5-diol, which resulted in the formation of 383 pmol of DNA adducts/mg DNA.…”

“…It is the further metabolism of this phenolic dihydrodiol to 5, 9, 10-trihydroxy-11,12-epoxy-9,10,11,12-tetra hydrobenzo [b]fluoranthene that has been linked to the genotoxic activity of benzo[b]fluoranthene in mouse skin (Weyand et al 1993b). In the case of benzo with DNA adduct formation in mouse skin (LaVoie et al 1993b;Weyand et al 1993a). …”

“…There is also evidence that application of either of these PAHs to mouse skin results in DNA adduct formation (Hughes et al 1993;LaVoie et al 1991aLaVoie et al , 1991bWeyand et al 1987Weyand et al , 1993a Benzo[g,h,i]perylene has been reported to be mutagenic in S. typhimurium and to cause DNA damage in E. coli. Benzo[g,h,i]perylene has been shown to be responsible for the formation of DNA adducts isolated after topical application of pharmaceutical grade coal tar to the skin of mice (Hughes et al 1993).…”

Integrating Field Analyses with Laboratory Exposures to Assess Ecosystems Health

“…Both anti-and syn-benzo [j]fluoranthene-9,10-diol-11,12-oxides formed DNA adducts after application to mouse epidermis. However, these adducts were not observed in the epidermis of mice treated with benzo [j]fluoranthene (Weyand et al, 1993a).…”

“…(ii) Formation of DNA adducts The major benzo [j]fluoranthene-DNA adduct produced in S. typhimurium TA97a and TA100 in the presence of Aroclor 1254-induced rat liver metabolic activation was an anti-benzo [j]fluoranthene -4,5-diol-6,6a-oxide-deoxyguanosine adduct (Marshall et al, 1993), which was also the major DNA adduct formed in mouse epidermis treated with benzo [j]fluoranthene (Weyand et al, , 1993a.…”