title: Modifying effect of propolis on dimethylhydrazine-induced DNA damage but not colonic aberrant crypt foci in rats.
abstract: Propolis is a honeybee product with several biological and therapeutic properties, including antimutagenic and anticarcinogenic activities. The effects of an aqueous extract of propolis (AEP) were evaluated on the formation of 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) and DNA damage in the colon of male Wistar rats by the ACF and Comet assays, respectively. AEP was administered orally at 0.01%, 0.03%, 0.1%, and 0.3% in the drinking water, which resulted in doses of approximately 12, 34, 108, and 336 mg/kg body weight/day. Animals were also given a single subcutaneous injection of 40 mg/kg DMH and sacrificed 4 hr later for evaluating DNA damage, or 4 doses of 40 mg/kg DMH, administered 2 doses/week for 2 weeks, and sacrificed 12 weeks after the last injection for evaluating ACF development in the distal colon. Administration of AEP either simultaneously with or after the DMH treatment resulted in no statistically significant reduction of ACF. In contrast, 0.01%, 0.03%, and 0.3% AEP, given simultaneously with DMH, reduced DNA damage induction in the mid and distal colon. However, 0.3% AEP alone increased DNA damage in the colon. In conclusion, AEP had no effect on the formation of DMH-induced ACF in rat colon, but it modulated DMH-induced DNA damage in colon cells. Further investigations are recommended in order to establish the conditions under which propolis produces either protective or deleterious effects.
authors.affiliation: Departamento de Patologia, Faculdade de Medicina, Universidade Estadual Paulista, Botucatu, São Paulo, Brazil.
authors.forename: Rodrigo O Alves
authors.initials: RO
authors.lastname: de Lima
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Bazo
authors.forename: Roueda A
authors.initials: RA
authors.lastname: Said
authors.forename: José Maurício
authors.initials: JM
authors.lastname: Sforcin
authors.forename: Vassya
authors.initials: V
authors.lastname: Bankova
authors.forename: Bruno R
authors.initials: BR
authors.lastname: Darros
authors.forename: Daisy M F
authors.initials: DM
authors.lastname: Salvadori
mesh_terms: D000818:Animals; D016587:Antimutagenic Agents / Q000494:pharmacology; D003106:Colon / Q000166:cytology; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000517:prevention & control*; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects*; D004127:Dimethylhydrazines / Q000633:toxicity*; D008297:Male; D009152:Mutagenicity Tests; D011230:Precancerous Conditions / Q000517:prevention & control; D011429:Propolis / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D016587:Antimutagenic Agents; D004127:Dimethylhydrazines; D011429:Propolis