Effect of ingestion of thermally oxidized sunflower oil on the fatty acid composition and antioxidant enzymes of rat liver and brain in development

Background. The current study was undertaken to assess the effects of oxidized sunflower oil ingestion (obtained by heating at 98degreesC with air insufflation during 48 h and incorporated at 5% in a fat-free diet) on liver and brain fatty acid composition, and some serum parameters and protective enzymes against peroxidation (glutathione peroxidase, glutathione reductase, catalase and glucose-6-phosphate dehydrogenase). Results: The main results show that the oxidized oil contains 262 mmol/kg of hydroperoxides, 5.7% of the esters are oxidized and 50.4% are polymerized. In the liver, we noticed that oxidized oil exercises a toxic effect as confirmed by the increase in the thiobarbituric acid reactive substance (TBARS) concentration. In the same way, we noticed that vitamin E exercises a favorable effect in the preservation against free radicals and lipid peroxidation; however, it cannot ensure this protection alone. In the liver, only glutathione peroxidase and glutathione reductase activities were positively correlated with the TBARS concentration. In the treated groups, we also noted changes in the fatty acid profiles of liver and brain homogenates, essentially by the appearance of trans fatty acid (18:1 trans) and an increase in arachidonic acid content.