Lethal effects of a linoleic acid hydroperoxide and its autoxidation products, unsaturated aliphatic aldehydes, on human diploid fibroblasts.

The lethal effects of linoleic acid and its hydroperoxide on human diploid fibroblasts were quite similar, and that of the reaction mixture from the autoxidation of the hydroperoxide was considerable. Some unsaturated aliphatic aldehydes, the secondary products of the hydroperoxide autoxidation, were identified and their toxicity toward the cells was examined. Among them, (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, and (E)-4-hydroxy-2-nonenal were the most toxic; e.g., in the presence of 25 microM nonadienal, decadienal, or hydroxynonenal, 75, 90, or almost 100% of the cells, respectively, underwent lysis within one day. Generally, alkenals were toxic and alkanals non-toxic. The toxicity was enhanced as the number of double bonds in each molecule was increased and also as the carbon chain was lengthened.