VITAMIN-E PROTECTS MONONUCLEAR LEUKOCYTE DNA AGAINST DAMAGE MEDIATED BY PHAGOCYTE-DERIVED OXIDANTS

The protective effects of physiological concentrations (3-12.5 mug/ml) of vitamin E (VE, dl-alpha-tocopherol) on the formation of DNA single -strand breaks in mononuclear leukocytes (MNL) in close proximity to a ctivated phagocytes have been investigated in vitro. Human neutrophils , activated by phorbol myristate acetate (PMA), induced DNA-strand bre aks in neighbouring lymphocytes. Vitamin E caused dose-related protect ion of MNL DNA against phagocyte-mediated oxidative damage. This appar ently novel protective activity of vitamin E is due primarily to the i nhibitory effects of this agent on the generation of reactive oxidants by activated neutrophils and is apparently unrelated to the classical oxidant-scavenging properties of VE.