8‐HYDROXY‐2′DEOXYGUANOSINE LEVELS AND ANTIOXIDANT STATUS IN RAT LIVER FED WITH OLIVE AND CORN OIL DIETS: EFFECT OF ASCORBIC ACID SUPPLEMENATION

DNA damage and antioxidants status were determined in liver of rat fed with olive and corn oil diets with and without ascorbic acid supplementation. In order to elucidate the role of fat intake, the study included a control and hyperlipidic diet. Liver antioxidant activities were significantly influenced by dietary fat and intake levels. In general, control groups fed with corn oil diets exhibited reduced liver antioxidant (SOD, catalase, and GSH-PX) and GSH levels compared with rats fed on olive oil diets. These activities were lower in rats consuming hyperlipidic diets relative to the control groups. Ascorbic acid supplementation resulted in a slight decrease of antioxidant activities both in the control and hyperlipidic diets with the exception of GSH that showed high levels in rats fed on an olive oil diet supplemented with ascorbic acid. The results of oxidative DNA damage as measured by the induction of 8-hydroxy deoxyguanosine (8-OHdG) clearly confirmed that corn diet (rich in polyunsaturated fatty acids) induced DNA damage in a dose- dependent manner. No induction of 8-OHdG was detected for the diet containing olive oil (monounsaturated diet). Ascorbic acid had no effect on rat fed on an olive oil diet. In contrast, for corn diets the ascorbic acid showed