Original Article J. Clin. Biochem. Nutr., 47, 18–26, July 2010 EtjJ01KOchoC098bryeu.18Bino3grS20N0tn1i-on9a605,cal-40iJl1o/e08a1jAtfcp96y6bCratfniloci.0nrle9iFc-ra1el1eB6tRiaoacdhiceamliRFsterayseatnrscdhNoJuaptraitnOionxidative-Antioxidative ffect of Die ry n Status of Blood in Rats Anna Walczewska1,*, Barbara Dziedzic1, Tomasz Stepien1, Elzbieta Swiatek1 and Dariusz Nowak2 1Department of Cell-to-Cell Communication, Medical University of Lodz, Lodz 92-215, Poland 2Department of Clinical Physiology, Medical University of Lodz, Lodz 92-215, Poland ;?7241R?097aec1cc0eeivpetedd2278.1.11..22001009 Received 27 November, 2009; Accepted 28 January, 2010; Published online 23 April, 2010 CopySriugmhtm©a2r0y10TJChBisNstudy was performed to examine the effect of different fat sources, lard, sunflower oil (SO), and fish oil (FO) in high-fat and low-fat diet on reactive oxygen species generation by blood phagocytes, glutathione redox status in erythrocytes, and total plasma antioxidant ability in rats. Whole blood chemiluminescence (CL) did not differ between three low-fat fed groups. However, baseline and phorbol myristate acetate (PMA)-stimulated CL in blood of high-lard fed rats were lower than in low-lard and high-SO fed animals. Phagocyte-stimulated oxidative burst was higher in rats fed high-SO diet than in those fed low-SO and high-FO diets. The highest level of oxidize glutathione (GSSH), the lowest reduce glutathione (GSH)/GSSG ratio in erythrocytes, and the highest plasma activity to reduce ferric ions were observed in rats fed both diets contaning linoleic acid-rich sunflower oil compared to animals fed the corresponding energy from other fats. 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of plasma was lower in high-lard and high-FO fed rats compared to the corresponding low-fat diets, and the lowest in low-FO fed rats among low-fat fed animals. We presume from our results that linoleic acid may have dual effect, prooxidative in blood cells but maintaining total antioxidant plasma ability. Key Words: high-fat diet, blood chemiluminescence, erythrocyte GSH/GSSG, FRAP, DPPH Introduction Besides fuel, dietary fats in mammals provide essential fatty acids for the membrane synthesis, protein and carbo- hydrate modifications, and signalling compounds [1]. How- ever, a high-fat diet depends on its fatty acids composition which could cause various health problems. The effects of a high-fat diet on oxidative stress in response to different dietary fats have been studied extensively [2–4], and comprise of a wide range of the oxidative stress parameters. It has been reported that high dietary polyunsaturated fatty acids series 3 (n-3 PUFA) increased erythrocyte membrane susceptibility to peroxidation [4, 5] and lipid peroxide *To whom correspondence should be addressed. Tel/Fax: +48-42-6782661 E-mail: anna.walczewska@umed.lodz.pl 18 products in rat liver and kidney [6]. Further research has demonstrated that dietary supplementation with n-3 PUFA has no effect on erythrocyte membrane peroxidation [7], or has a positive effect on the glutathione level and antioxidant enzyme activity in blood [8]. The question remains whether there is increased susceptibility of the membranes to per- oxidation, or an increased amount of the lipid peroxidation products resulted from enhanced reactive oxygen species (ROS) generated by blood phagocytes, or dysfunction of the antioxidant systems in blood, or both. Health concequences of a high saturated fatty acid dieting are investigated most frequently in relation to the lipid metabolism and mecha- nisms of hyperlipidemia which play a crucial role in arterio- sclerosis, hypertension, and ultimately cardiovascular dis- ease [9, 10]. The studies on the effect of a high saturated fatty acid diet on oxidative stress in particular tissues have shown different results. Zhang and his co-workes [11] have reported that a high lard diet increases NADPH-dependent