Dietary garlic suppresses DNA adducts caused by N-nitroso compounds.
The present studies examined the impact of a processed garlic powder on the in vivo occurrence of DNA adducts caused by N-nitroso compounds (NOC) in rats. Addition of 2% garlic powder to diets containing aminopyrine and sodium nitrite (each at 600 mg/kg) reduced the occurrence of both 7-N-methyldeoxyguanosine (7-N-mG) and 6-O-methyldeoxyguanosine (6-O-mG) adducts to rat liver DNA by approximately 55%; and over 80% when 4% garlic was provided. Dietary supplementation with garlic powder (2 and 4%) also reduced the occurrence of 7-N-mG and 6-O-mG adducts by approximately 40 and 60% respectively, in rats intubated with N-nitrosodimethylamine (150 mg/kg body wt). The quantity of 7-N-mG and 6-O-mG adducts in mammary tissue of rats given intravenous N-methyl-N-nitrosourea (50 mg/kg body wt) was reduced over 50% in rats fed 2% garlic compared to controls. The depression in the occurrence of these adducts was approximately 70% when dietary garlic was increased to 4%. These experiments suggest the reduction in DNA adducts caused by processed garlic powder likely reflects a depression in the formation of NOC from precursors and changes in the bioactivation and/or denitrosation of NOC.
Lin
X Y
XY
Department of Nutrition, Pennsylvania State University, University Park 16802.
Liu
J Z
JZ
Milner
J A
JA
D000818:Animals; D016588:Anticarcinogenic Agents; D001711:Biotransformation; D004247:DNA / Q000187:drug effects*; D004249:DNA Damage; D004032:Diet; D005260:Female; D005737:Garlic; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008770:Methylnitrosourea / Q000493:pharmacokinetics / Q000633:toxicity*; D009603:Nitroso Compounds / Q000493:pharmacokinetics / Q000633:toxicity*; D010946:Plants, Medicinal; D051381:Rats; D017207:Rats, Sprague-Dawley
D016588:Anticarcinogenic Agents; D009603:Nitroso Compounds; C008651:4-nitrosodimethylaniline; D008770:Methylnitrosourea; D004247:DNA