Protective Effect of Vegetarian Food Extracts against DNA Damages in Ex Vivo Human Lymphocyte

Abstract

Food such as fruits and vegetables have high contents of antioxidants. They can reduce the risk of various diseases such as cancers and heart diseases by increasing the antioxidant capacity in the body and reducing damages caused by reactive oxygen species inside cells. Koreans mainly eat vegetables with high antioxidant capacities such as cereals, legumes, vegetables, and mushrooms. It is expected that food taken by Koreans could have high protective effect against DNA damage. The objective of this study was to determine protective effect of vegetarian food against DNA damage ex vivo. Vegetarian food were divided into ten food groups. Extracts from the ten groups were extracted and used to treat human lymphocyte. The variety of vegetables were selected based on the results of the fifth Korean National Health and Nutrition Examination Survey (KNHANES V‐2). The ten food groups were: cereals, potatoes, legumes, nuts, vegetables, kimchies, mushrooms, fruits, seaweeds, and oils. A total of 84 food varieties taken at more than 1% in the total food intake by Koreans were selected as vegetarian food. Selected food varieties were washed and freeze‐dried followed by methanol‐acetone extraction. DNA damage was measured using COMET assay to determine the indices of tail length (TL) pulled from nucleus, DNA % (% DNA in tail, TD) included at the tail, and tail moment (TM, a multiplied value of TL by TD). Pre‐treatment to lymphocyte with all ten Korean diet extracts showed significantly higher reduction effect against DNA damage induced by H2O2 compared to control group without receiving any pre‐treatment. The order of protective effect against DNA damages in the TD was: mushrooms > vegetables > fruits > seaweeds > nuts. The order of protective effect against DNA damages in the TL was: mushrooms > fruits > vegetables > nuts > seaweeds. The order of protective effect against DNA damages in terms of TM was: mushrooms > vegetables > fruits > seaweeds > kimchies. Mushrooms showed the highest protective effect against DNA damages in all three indices (TL, TD, and TM) representing DNA damages.Support or Funding InformationThis research was supported by a grant (NRF‐2013R1A1A3006963) of the Basic Science Research Program of the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology, Republic of Korea.