Prevention of oxidative DNA damage by bioactive berry components.
The hormone 17ss-estradiol (E(2)) causes oxidative DNA damage via redox cycling of its metabolites such as 4-hydroxy estradiol (4E(2)). In this study, ACI rats (8 wk old) were fed either AIN-93M diet or diets supplemented with 0.5% each of mixed berries (strawberry, blueberry, blackberry, and red and black raspberry), blueberry alone (BB; 2.5%), or ellagic acid (EA; 400 ppm) from 2 wk prior to and up to 12 wk of E(2) treatment. The liver DNA was analyzed for the presence of 8-oxo-7,8-dihydroguanine (8-oxodG) and other polar adducts by 32P-postlabeling. Compared to sham treatment, E(2) significantly increased the levels of both 8-oxodG and P-1 subgroup (259% and 214%, respectively; P< 0.05). EA diet significantly reduced E(2)-induced levels of 8-oxodG, P-1, P-2, and PL-1 by 79, 63, 44, and 67%, respectively (P< 0.001). BB diet also significantly reduced the levels of P-1, P-2, and PL-1 subgroups by 77, 43, and 68%, respectively (P< 0.001). Mixed berries were, however, ineffective. In addition, aqueous extracts of berries (2%) and EA (100 microM) were tested for their efficacy in diminishing oxidative DNA adducts induced by redox cycling of 4E(2) catalyzed by copper chloride in vitro. EA was the most efficacious (90%), followed by extracts of red raspberry (70%), blueberry, and strawberry (50% each; P< 0.001).
Aiyer
Harini S
HS
Brown Cancer Center, Delia Baxter II, Room 304E, 580 Preston Street, Louisville, KY 40202, USA.
Kichambare
Sunita
S
Gupta
Ramesh C
RC
D000818:Animals; D000872:Anthocyanins / Q000032:analysis; D003300:Copper / Q000633:toxicity; D018736:DNA Adducts / Q000032:analysis; D004249:DNA Damage; D004610:Ellagic Acid / Q000032:analysis / Q000494:pharmacology*; D004958:Estradiol / Q000031:analogs & derivatives / Q000633:toxicity; D002393:Estrogens, Catechol; D005260:Female; D005638:Fruit / Q000737:chemistry; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D011912:Rats, Inbred ACI
D000872:Anthocyanins; D018736:DNA Adducts; D002393:Estrogens, Catechol; D010936:Plant Extracts; D004610:Ellagic Acid; D004958:Estradiol; D003300:Copper; C014036:4-hydroxyestradiol; C029892:cupric chloride