Fatty Acid Composition and Oxidative Stress Parameters in Plasma after Fish Oil Supplementation in Aging

Fish oil affects oxidative stress parameters and changes in phospholipids fatty acids profiles in plasma, erythrocytes and tissues. We examined the effects of fish oil supplementation in young and old male Wistar rats (3 and 22 months old) on plasma phospholipids fatty acids profiles and blood oxidative stress parameters. Twenty young and twenty aged Wistar rats were randomly divided into four groups (ten animals each): two control groups and two supplemented groups treated for 6 weeks with fish oil capsules containing 45 mg eicosapentanoic acid (EPA) and 30 mg docosahexanoic acid (DHA). Fish oil supplementation changed the percentage of long chain fatty acids (FAs): the elevated percentage of eicosatrienoic acid (ETA, 20:3), eicosapentanoic (EPA, 20:5), docosapentanoic acid (DPA, 22:5), n-3 fatty acids and decreased arachidonic acid (AA, 20:4). However, there were no age-related changes in total SH groups, the percentages of palmitic (16:0), palmitoleic (16:1), oleic (18:1 (n-9)) and linoleic acid (18:2) in plasma phospholipids and MUFA and they were neither reversed nor prevented by fish oil supplementation. Results showed that fish oil supplementation increased SOD and CAT activities in erythrocytes, and PON activity in the blood plasma of both young and aged rats. Furthermore, fish oil supplementation decreased lipid peroxidation (MDA) and nitrite levels in both young and aged rats implying better antioxidant protection and a lower level of oxidative pressure after fish oil supplementation. Our results suggest that fish oil supplementation is beneficial regarding better antioxidant protection in both young and aged rats, while applied treatment differs in plasma phospholipids FAs composition