Comparison of the Protective Effect of Antioxidant Vitamins and Fruits or Vegetable Juices on DNA Damage in Human Lymphocyte Cells Using the Comet Assay

ABSTRACT

In this study the in vitro protective effects of several antioxidant vitamins (vitamin C, alpha-tocopherol, beta-carotene), fruits and vegetables (strawberry, tangerine, orange and 100% orange juice, carrot juice), on the levels of isolated human lymphocyte DNA damage was measured using Comet assay. Comet assay has been used widely to assess the level of the DNA damage in the individual cells. Lymphocytes were pre-treated for 30 minutes with antioxidant vitamins (10, 50, 100, 500 micrometer) or fruits. vegetables (10, 100, 500, 1000 microgram/ml), an4 then oxidatively challenged with 100 micrometer H2O2 for 5 min at 4degrees C. The protective effect of antioxidant vitamins against DNA damage at a concentration of 50 micrometer were 50% in vitamin C, 32% in alpha-tocopherol, whereas, beta-carotene showed a 55% protection at a dose as low as 10micrometer. The inhibitory effects of DNA damage by strawberry, tangerine, orange, orange juices, carrot juices were 50 - 60% with wide ranges of doses. The results of the present study indicate that most the antioxidant vitamins and fruits.vegetables juices produced a significant reduction in oxidative DNA damage.