Prevention of oxidative DNA damage by bioactive berry components

Area of Science:

• Biochemistry
• Toxicology
• Nutritional Science

Background:

• 17β-estradiol (E(2)) and its metabolites can induce oxidative DNA damage through redox cycling.
• This damage is characterized by the formation of DNA adducts like 8-oxo-7,8-dihydroguanine (8-oxodG).
• Dietary interventions may offer protection against hormone-induced genotoxicity.

Purpose of the Study:

• To investigate the protective effects of berry-derived compounds and ellagic acid against E(2)-induced oxidative DNA damage in ACI rats.
• To evaluate the in vitro efficacy of berry extracts and ellagic acid in preventing DNA adduct formation.

Main Methods:

• ACI rats were fed diets containing mixed berries, blueberry alone, or ellagic acid (EA) during 17β-estradiol (E(2)) treatment.
• Liver DNA was analyzed for 8-oxodG and other polar adducts using 32P-postlabeling.
• In vitro assays assessed the ability of berry extracts and EA to reduce DNA adducts induced by 4-hydroxy estradiol (4E(2)) and copper chloride.

Main Results:

• E(2) treatment significantly increased levels of 8-oxodG and P-1 DNA adducts compared to sham treatment.
• Ellagic acid (EA) diet significantly reduced E(2)-induced 8-oxodG, P-1, P-2, and PL-1 adducts.
• Blueberry (BB) diet also significantly reduced P-1, P-2, and PL-1 adducts, while mixed berries were ineffective.
• In vitro, EA demonstrated the highest efficacy (90%) in reducing DNA adducts, followed by red raspberry (70%), blueberry, and strawberry (50% each).

Conclusions:

• Ellagic acid and blueberry consumption can mitigate 17β-estradiol-induced oxidative DNA damage in vivo.
• Berry extracts, particularly red raspberry and blueberry, possess in vitro antioxidant properties that protect against DNA adduct formation.
• Dietary strategies incorporating specific berry components may be beneficial in preventing hormone-related genotoxicity.