Abstract：
:N-Methyl-N-nitrosourea (MNU) is a reactive, mutagenic methylating agent. MNU methylates DNA at various sites, including guanine N7, guanine O6, and adenine N3. Dixit and Gold [(1986) Proc. Natl. Acad. Sci. U.S.A. 83, 8039-8043] reported that ellagic acid, a phenolic natural product, inhibited the mutagenicity of MNU in Salmonella typhimurium strain TA 100, inhibited salmon sperm DNA alkylation by [3H]MNU, and also greatly reduced the ratio of guanine O6 to guanine N7 alkylation. We have examined the MNU-induced alkylation of calf thymus DNA and evaluated the effect of ellagic acid on this binding. Ellagic acid had only a slight effect on total alkylation and did not alter the ratio of methylation at guanine-O6 and -N7 positions. In further experiments, ellagic acid did not significantly inhibit MNU mutagenicity. These findings do not support the potential use of ellagic acid as an inhibitor of biological damage induced by nitrosoureas.
journal_name
Chem Res Toxicoljournal_title
Chemical research in toxicologyauthors
Lord HL,Josephy PD,Snieckus VAdoi
10.1021/tx00015a002subject
Has Abstractpub_date
1990-05-01 00:00:00pages
195-8issue
3eissn
0893-228Xissn
1520-5010journal_volume
3pub_type
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