ENRICHMENT WITH ARACHIDONIC-ACID INCREASES THE SENSITIVITY OF HEPATOMA-CELLS TO THE CYTOTOXIC EFFECTS OF OXIDATIVE STRESS

Hepatoma cells are, at most, moderately sensitive to oxidative stress. An important cause of this lack of sensitivity is the decreased content of polyunsaturated fatty acids in comparison with normal cells. These fatty acids are one cellular target of oxygen radicals, by which they are broken down into several toxic carbonyl compounds. If the membrane phospholipids of tumor cells are enriched with polyunsaturated fatty acids, such as arachidonic acid, they become able to undergo lipid peroxidation in the presence of prooxidants. This effect is studied in the highly deviated Yoshida AH-130 ascites hepatoma and in two rat hepatoma cell lines. In parallel to their increased lipid peroxidation, cells enriched with arachidonic acid and exposed to ascorbic acid/FeSO4 showed lower viability and growth than unenriched ones.