Antioxidant potential of evening primrose oil administration in hyperlipemic rabbits

The dietary intake of saturated fatty acids affects arteriosclerosis. We st udied the effect of supplementation (15% wt/wt) of a hyperlipemic diet (1.3 3% cholesterol) with evening primrose oil (EPO) (Oenothera biennis) for 6 w eeks in four groups of 10 rabbits each. At the end of this period we determ ined lipid peroxidation, glutathione content, and glutathione peroxidase, r eductase and transferase activities in liver, brain, heart, aorta and plate lets. The atherogenic diet increased tissue lipid peroxidation and decrease d the protective antioxidant effect of glutathione. Dietary supplementation with EPO reduced tissue lipid peroxidation (61% in liver, 57% in brain, 42 % in heart, 24% in aorta, 33% in platelets). Total glutathione was increase d, especially in the aorta (90%) and platelets (200%); however, in all tiss ues the percentage of oxidised glutathione decreased. Evening primrose oil reduced glutathione peroxidase activity and increased the activities of glu tathione reductase and transferase. We conclude that in rabbits made hyperl ipemic with a diet rich in saturated fatty acids, EPO decreased tissue oxid ative stress.