title: The pineal hormone melatonin inhibits DNA-adduct formation induced by the chemical carcinogen safrole in vivo.
abstract: Melatonin inhibits DNA-adduct formation induced by the chemical carcinogen safrole in a dose-dependent manner. Total DNA-adduct formation after in vivo administration of 300 mg/kg safrole measured by 32P-postlabeling analysis of carcinogen-modified DNA in rat liver was 36,751 +/- 2290 counts/min/10 micrograms DNA. Coadministration of 300 mg/kg safrole with either 0.2 mg/kg (low dose) or 0.4 mg/kg (high dose) melatonin reduced DNA-adduct formation induced by safrole to 22,182 +/- 987 counts/min/10 micrograms DNA and 462 +/- 283 counts/min/10 micrograms DNA, respectively. Circulating melatonin concentrations at the termination of the study in safrole, low melatonin and high melatonin groups were 50 +/- 8, 3140 +/- 430 and 10,040 +/- 2610 pg/ml serum, respectively. The results suggest that melatonin protects against safrole associated DNA damage.
authors.affiliation: Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284-7762.
authors.forename: D X
authors.initials: DX
authors.lastname: Tan
authors.forename: B
authors.initials: B
authors.lastname: Pöeggeler
authors.forename: R J
authors.initials: RJ
authors.lastname: Reiter
authors.forename: L D
authors.initials: LD
authors.lastname: Chen
authors.forename: S
authors.initials: S
authors.lastname: Chen
authors.forename: L C
authors.initials: LC
authors.lastname: Manchester
authors.forename: L R
authors.initials: LR
authors.lastname: Barlow-Walden
mesh_terms: D000818:Animals; D004247:DNA / Q000187:drug effects / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012451:Safrole / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D004247:DNA; D008550:Melatonin; D012451:Safrole