Garlic extracts protects from genetic damage by hydrogen peroxide and 4-Hydroxy-2-Nonenal in human leukocytes

Garlic acquired a reputation in the folklore of many cultures over centuries as a formidable prophylactic and therapeutic medicinal agent. Garlic has attracted particular attention of modern medicine because of its widespread health use around the world [1]. In the present study, we evaluated the effect of garlic extracts on H₂O₂ or 4-Hydroxy-2-Nonenal (HNE) induced oxidative DNA damage in human leukocytes. The samples were prepared by extracting raw, roasted and pickled garlic with four different solvents (methanol, ethanol, acetone, and water). Human leukocytes were incubated in medium with PBS (negative control) or with garlic extracts (1, 5, 10, and 50µg/ml) for 30min at 37°C were further treated with H₂O₂ (200µM) for 5min on ice or HNE (200µM) for for 30min at 37°C as an oxidative stimulus. Oxidative damage was evaluated by Comet assay (single-cell gel electrophoresis) and quantified as % fluorescence in tail. Results showed that pretreatment of garlic extracts for 30min had a preventive effect on either H₂O₂ or HNE induced DNA damage, regardless of preparation methods and extract solvents. We conclude that garlic could be an effective agent or food supplement in reducing the genotoxicity of H₂O₂ or HNE and the antigenotoxic effect of garlic would not be affected by roasting and pickling.

References: 1. Banerjee, S.K., Maulik, S.K. (2002) Nutr. J. 1: 4.