Protective effect of phenolic antioxidants on the cytotoxicity induced by phosphatidylcholine hydroperoxide

Phosphatidylcholine hydroperoxides show weak but distinct toxicity toward cultured human umbilical vein endothelial cells. The protective effect of phenolic antioxidants against the cytotoxicity of phosphatidylcholine hydroperoxides was examined. Probucol depressed the toxicity most effectively among the antioxidants studied under both pretreatment and concurrent treatment conditions. alpha-Tocopherol showed a protective effect in the case of concurrent treatment. Protection by phenolic antioxidants against the cytotoxicity of phosphatidylcholine hydroperoxides seems to depend on their incorporation rate into cells, their affinity for phospholipids, their antioxidative activity, and their orientation in membranes.