LIPID PEROXIDATION IN CONTROL AND RAS-TRANSFORMED FIBROBLASTS AFTER INCORPORATION OF POLYUNSATURATED FATTY ACIDS

Investigations were carried out on the alterations in the lipid peroxide level in control and ras-transformed fibroblasts enriched with two polyunsaturated fatty acids with different degree of unsaturation (linoleic acid (LA) and eicosa-heptoenoic acid (EPA)) before and after exposure to oxidative stress induced by hydrogen peroxide. The obtained results demonstrated a higher rate of incorporation of EPA in both control and ras-transformed cells compared to LA. After incorporation of the corresponding fatty acids, the content of lipid per-oxides was always higher in the oncogene-transformed cells in comparison with the control ones. In the cells treated with hydrogen peroxide was observed a significant elevation of the lipid peroxide level, which was more marked in the LA-enriched cells. We suggest that this observation could be ascribed to the specific conformation of some polyunsaturated fatty acids, which show an unexpected oxidative stability under definite circumstances.