Protection against hydroxyurea-induced cytotoxic effects in L5178Y cells by free radical scavengers

Exposure of L5178Y cells in culture to 1 mM hydroxyurea (HU) for 3 h followed by 24 h incubation in an HU-free medium induced an abnormal enlargement of about 40% of the cells in the population and post-treatment reduction of DNA synthesis in comparison with control cells. These effects were used to examine the protection afforded by free radical scavengers against HU-induced cytotoxicity. It has been found that with careful choice of conditions (suitable concentration of the protective agent, pretreatment of cells) substantial protective effect of alpha-tocopherol, sodium benzoate, acetylsalicylic acid, catalase, peroxidase or superoxide dismutase can be achieved.