Desmutagenic and bio-antimutagenic activity of docosahexaenoic acid and eicosapentaenoic acid in cultured Chinese hamster V79 cells

The antimutagenic activities of docosahexaenoic acid (DHA) and eicosapentae noic acid (EPA) were examined by studying their effects on induction of 6-t hioguanine (6TG)-resistant mutations by ethyl methanesulfonate (EMS) in cul tured Chinese hamster V79 cells. DRA had a remarkable inhibitory effect aga inst the cytotoxicity of EMS, when cells were simultaneously-treated with E MS, showing a blocking or scavenging activity of DHA in reduction of surviv ing fraction of cells. DHA had not so significant effect, when cells were t reated before and after treatment with EMS. On the other hand, EPA had mark ed inhibiting effects against cytotoxicity of EMS, when cells were treated with EPA, before, simultaneous and after treatment with EMS. Against the in duction of mutations by EMS, an antimutagenic activity of DHA was found whe n cells were pre-treated, simultaneously-treated or post-treated with DHA. EPA was also effective in reducing EMS-induced 6TG-resistant mutations when the cells were treated using the three different treatment procedures desc ribed above. The results suggest that in cultured Chinese hamster V79 cells , DHA and EPA may have both desmutagenic activity, which inactivates EMS ch emically and/or enzymatically and bio-antimutagenic activity which suppress es mutation fixation after DNA is damaged by EMS. (C) 2001 Elsevier Science B.V. All rights reserved.