114E-22 |
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K. J. JUNG and K. W. Singletary. Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 484 Bevier Hall, 905 South Goodwin Ave., Urbana, IL 61801 There is considerable interest in identifying natural products that may prevent breast cancer. Concord grapes are rich in polyphenolic compounds and anthocyanin pigments that may have anticarcinogenic properties due to antioxidant, antiproliferative, and proapoptotic actions. In order to determine the potential breast cancer protective action of Concord grape juice consumption toward the initiation stage of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis and on the formation of rat mammary DNA adducts, Sprague-Dawley female rats were provided Concord grape juice in the drinking water at phenolic concentrations of 346, 519, and 692 mg/dL beginning three weeks before dosing with DMBA (35 mg/kg body wt) at 50 days of age and ending the third day after dosing. Consumption of grape phenolics significantly inhibited mammary tumor mass at study termination, but was associated with a statistically significant inhibition of cumulative palpable tumor volume only during the first 5 weeks of tumor formation. In addition, consumption of grape juice phenolics significantly inhibited in vivo DMBA-DNA adduct formation as well as oxidative DNA damage in several tissues. Total mammary DMBA-DNA adduct formation decreased by 34% and 56% for animals fed phenolics at 346 and 692 mg/dL respectively, compared to controls. Liver DMBA-DNA adducts decreased by 22 to 44%, and mammary 8-oxo-dG levels decreased by 10% and 31%, respectively. Thus, specific individual constituents or combinations of phytochemicals in Concord grape juice can inhibit DNA damage in mammary gland and liver, and inhibit the initiation stage of DMBA-induced rat mammary tumorigenesis.
Session 114E, Nutraceuticals & Functional Foods: Bioactivity measurement and mechanism
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