DNA Damage by Endogenous and Exogenous Aldehydes

The present overview describes the formation of deoxyribonucleic acid (DNA) adducts from endogenous and exogenous aldehydes, such as acetaldehyde, acrolein, crotonaldehyde. malonaldehyde. 4-hydroxy-2-nonenal and 2,4-decadienal. Malonaldehyde reacts with 2'-deoxyguanosine. 2'-deoxyadenosine, and 2'-deoxycytidine, yielding cyclic pyrimidopurinone and acyclic adducts. The direct addition of alpha,beta-unsaturated aldehydes to DNA bases yields cyclic substituted propano adducts. such as 1,N-2-propano-2'-deoxyguanosine. Alternatively. alpha,beta-unsaturated aldehydes can be oxidized to reactive epoxides, giving ethano or etheno derivatives upon reaction with DNA. In addition, information on highly sensitive techniques, employed for the in vivo detection and quantification of DNA-aldehyde adducts, is also provided. Some of these DNA-aldehyde lesions have been shown to be highly mutagenic. In fact, lipid peroxidation and exogenous aldehyde exposure could potentially account for the observed carcinogenicity of urban air pollution and cigarette smoke exposure.