Linked Life Data

12387621

Source:http://linkedlifedata.com/resource/pubmed/id/12387621

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2002-10-21
pubmed:abstractText
Alcohol consumption is associated with an increased risk of cancer by mechanisms that remain unknown but have been suggested to involve radical metabolites. We have previously shown that the 1-hydroxyethyl radical produced from ethanol oxidation in vitro is able to alkylate nucleic acids to produce C8-(1-hydroxyethyl)guanine [C8-(1-HE)gua] among other products. To assess if this adduct is produced in vivo, we developed a sensitive HPLC-MS/MS method for its detection and analyzed hydrolysates of liver RNA and DNA from control and ethanol-treated rats. Unexpectedly, C8-(1-HE)gua was found to be present in both RNA and DNA from the liver of control Sprague-Dawley rats, and its levels increased slightly, but not significantly, after an acute ethanol dose (5 g/kg). In rat liver, C8-(1-HE)gua endogenous levels were about 10 times higher in RNA (35 +/- 5/10(7) guanine) than DNA (3.7 +/- 1.1/10(7) guanine). These levels were also found in commercial RNA (calf liver and yeast) and DNA (calf thymus), further indicating the endogenous source of the adduct. DNA basal levels of C8-(1-HE)gua were similar to those reported for other 2C guanine adducts such as N7-(2-hydroxyethyl)guanine and N2-ethyl-2'-deoxyguanosine. We speculate that all of these adducts may be generated from DNA attack by products of basal lipid peroxidation. The higher RNA levels of C8-(1-HE)gua are in agreement with the higher accessibility of RNA and nucleotides to reactive intermediates because they are not as protected or as localized as DNA. Chemical modification of RNA has been receiving increasingly attention as an important event in genotoxic mechanisms. Comparison of RNA basal levels of C8-(1-HE)gua, N7-(2-hydroxyethyl)guanine, and N2-ethyl-2'-deoxyguanosine may provide clues about their endogenous sources and biological significance. Yet, the marginal increase of DNA C8-(1-HE)gua upon ethanol administration argues against this adduct playing a major role in the carcinogenic effects of ethanol.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0893-228X
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1248-53
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Detection of C8-(1-hydroxyethyl)guanine in liver RNA and DNA from control and ethanol-treated rats.
pubmed:affiliation
Departamento de Bioquímica, Instituto de Química and Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't