Evaluation of the Mutagenic Potential of the Principal DNA Adduct of Acrolein

Abstract

Acrolein is produced extensively in the environment by incomplete combustion of organic materials, and it arises endogenously in humans as a metabolic by-product. Acrolein reacts with DNA at guanine residues to form the exocyclic adduct, 8-hydroxypropanodeoxyguanosine (HOPdG). Acrolein is mutagenic, and a correlation exists between HOPdG levels in Salmonella typhimurium treated with acrolein and a resultant increase in mutation frequency. Site-specifically modified oligonucleotides were used to explore the mutagenic potential of HOPdG in Escherichia coli strains that were either wild-type for repair or deficient in nucleotide excision repair or base excision repair. Oligonucleotides modified with HOPdG were inserted into double-stranded bacteriophage vectors using the gapped-duplex method or into single-stranded bacteriophage vectors and transformed into SOS-induced E. coli strains. Progeny phage were analyzed by oligonucleotide hybridization to establish the mutation frequency and the spectrum of mutations produced by HOPdG. The correct base, dCMP, was incorporated opposite HOPdG in all circumstances tested. In contrast, in vitro lesion bypass studies showed that HOPdG causes misincorporation opposite the modified base and is a block to replication. The combination of these studies showed that HOPdG is not miscoding in vivo at the level of sensitivity of these site-specific mutagenesis assays.

Formation of Acrolein-derived 2′-Deoxyadenosine Adduct in an Iron-induced Carcinogenesis Model

“…In later studies, the 1,N 2 -propano-2Ј-deoxyguanosine adduct was detected in the DNA extracted from rat and human liver (31)(32)(33) and from lymphocyte DNA in patients undergoing treatment with cyclophosphamide, a precursor of acrolein (34,35). It is striking to note that the acrolein-derived 2Ј-deoxyguanosine adducts are mutagenic in vitro and in vivo (36,37). This may be correlated to our previous findings that the acrolein adduct (FDP-lysine) was markedly generated in the livers of rats exposed to the carcinogenic chemicals, such as butylated hydroxyanisole, 4-dimethylaminoazobenzene, and 2-acetylaminofluorene (38).…”

Repair of exocyclic DNA adducts: rings of complexity

“…The involvement of NER is indicated by both increased mutation frequency and increased adducted-template replication in the NER-deficient strains. Similarly, it was recently shown (84)(85)(86)(87) that E. coli NER is also implicated in repair of the major acrolein-derived DNA adduct, g-HO-PdG (Fig. 3), which has been detected in DNA from healthy human tissues.…”

“…The latter can be excised by DNA glycosylases, (36,48) in addition to NER. (76) In contrast, M 1 G, PdG and HO-PdG are not recognized by glycosylase-mediated BER, as tested in vitro (36) or in vivo, (83)(84)(85) suggesting that BER may not be involved in repair of six-membered adducts. However, not all known DNA glycosylases have been tested for their activities toward these adducts and it is still unknown as to what repair mechanism(s) is involved in removal of other six-membered exocyclic adducts of dA and dC.…”

Characterization of Acrolein-Glycerophosphoethanolamine Lipid Adducts Using Electrospray Mass Spectrometry

“…This 1-N 2 -propano-2′-deoxyguansoine adduct was detected in DNA isolated from human and animal tissues (38,39), and the levels of this adduct were found to be significantly higher in the oral tissues of cigarette smokers as compared to nonsmokers (40). Such acrolein adducts of 2′-deoxyguanosine were found to be mutagenic in vitro and in vivo (41,42). Acrolein readily reacts with lysine side chains of proteins and forms quite stable adducts.…”