Linked Life Data

3986960

Source:http://linkedlifedata.com/resource/pubmed/id/3986960

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1985-6-14
pubmed:abstractText
Dietary-related indoles, isothiocyanates, and the allyl isothiocyanate glucosinolate, sinigrin, were administered to F344 rats in the diet for 2 weeks (chronic protocol) or by gavage 2 h before sacrifice (acute protocol) and the effects of these pretreatments on the alpha-hydroxylation of two carcinogenic nitrosamines, N-nitrosodimethylamine (NDMA) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), were evaluated. alpha-Hydroxylation was measured in vitro by quantitation of formaldehyde formation upon incubation of the nitrosamines with liver microsomes, and in vivo by quantitation of levels of 7-methylguanine and O6-methylguanine in hepatic DNA, 4 h after nitrosamine treatment. Compounds shown to be inhibitory in the in vitro assay were selected to be further evaluated using the in vivo assay. The results of the in vitro assays showed that indoles were inducers of the demethylation of both nitrosamines. Indole, L-tryptophan and indole-3-carbinol were strong inducers of NDMA and NNK demethylation, respectively. In contrast, isothiocyanates such as phenethyl isothiocyanate and phenyl isothiocyanate demonstrated a wide range of inhibitory activities toward demethylation of these nitrosamines in both the acute and chronic studies. Chronic, but not acute, pretreatment with sinigrin also caused a significant decrease in the demethylation of NDMA and NNK. In view of their promising inhibitory activities, the effects of phenethyl isothiocyanate, phenyl isothiocyanate and sinigrin on the in vivo methylation of DNA by NDMA and NNK were evaluated. The results were parallel to those obtained in the in vitro assays. Phenethyl isothiocyanate, phenyl isothiocyanate and sinigrin generally inhibited the formation of 7-methylguanine and O6-methylguanine in rat hepatic DNA. The results of this study suggest that these compounds could be anticarcinogenic to NDMA and NNK.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0143-3334
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
539-43
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Effects of dietary indoles and isothiocyanates on N-nitrosodimethylamine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone alpha-hydroxylation and DNA methylation in rat liver.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.