Protective effects of β-carotene and silymarin on human lymphocytes

Beta-carotene and silymarin have antioxidant properties against oxidative damage and are used as dietary supplements. The aim of this study was to assess the protective effects of β-carotene and silymarin on healthy human lymphocytes exposed to L-arginine-induced oxidative damage. Study samples were lymphocyte cultures set up from venous blood obtained from 6 healthy individuals (3 males and 3 females). Oxidative DNA damage was induced by L-arginine. β-Carotene and silymarin were added to the cultures as antioxidants to observe their protective effects, if any. Alkaline single-cell gel electrophoresis (SCGE) was used to evaluate DNA damage. While L-arginine generated genotoxic damage in the lymphocyte cultures, both β-carotene and silymarin had positive effects on the reversal of the induced genotoxicity. When β-carotene was applied in combination with silymarin, there was no significant change in mean tail moments in comparison to the use of β-carotene or silymarin alone. The data presented here provide a comparative, preliminary insight into the protective role of both β-carotene and silymarin on L-arginine-induced genotoxicity in in vitro lymphocyte cultures.