The effects of selenium (Se) on antioxidant defense system in liver and kidneys of rats with cadmium (Cd)-induced toxicity were examined. Cd exposure (15 mg Cd/kg b.m./day as CdCl2 for 4 weeks) resulted in increased lipid peroxidation (LP) in both organs (p<0.005 and p<0.01). Vitamin C (Vit C) was decreased in the liver (p<0.005), whereas vitamin E (Vit E) was increased in the liver and kidneys (p<0.005 and p<0.05) of Cd-exposed animals. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were decreased in both tissues (p<0.05 and p<0.005), whereas catalase (CAT) activity was decreased only in liver (p<0.005). Glutathione S-transferase (GST) increased in both tissues (p<0.005 and p<0.01). Treatment with Se (0.5 mg Se/kg b.m./day as Na2SeO3 for 4 weeks) significantly increased liver and kidneys SOD and GSH-Px activities (p<0.05 to p<0.005), as well as CAT and GST activities only in the liver (p<0.01). In animals exposed to Se, both the concentrations of Vit C (p<0.01) and Vit E (p<0.005) were increased in both tissues. Co-treatment with Se resulted in reversal of oxidative stress with significant decline in analyzed tissues Cd burden. Our results show that Se may ameliorate Cd-induced oxidative stress by decreasing LP and altering antioxidant defense system in rat liver and kidneys and that Se demonstrates the protective effect from cadmium-induced oxidative damage., B. I. Ognjanović, S. D. Marković, S. Z. Pavlović, R. V. Žikić, A. Š. Štajn, Z. S. Saičić., and Obsahuje bibliografii a bibliografické odkazy
The effects of acute exposure to cadmium (Cd) on the blood antioxidant defense system, lipid peroxide concentration and hematological parameters, as well as the possible protective role of vitamin E were studied. Male Wistar albino rats (3 months old) were treated with cadmium (0.4 mg Cd/kg b.m., i.p., 24 h before the experiment) or with vitamin E + Cd (20 IU Vit E/kg b.m., i.m., 48 h + 0.4 mg Cd/kg b.m., i.p., 24 h before the experiment). The hematological parameters were assessed: red blood cell counts, hematocrit value and hemoglobin concentration were significantly decreased in the blood of Cd-treated rats. Intoxication with cadmium was also followed by significantly increased lipid peroxide concentrations. We also observed increased activity of antioxidant defense enzymes: copper zinc containing superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase as well as concentrations of non-enzymatic components of antioxidant defense system: reduced glutathione, vitamin C and vitamin E. Pretreatment with vitamin E exhibited a protective role on the toxic effects of cadmium on the hematological values, lipid peroxide concentration as well as on enzymatic and non-enzymatic components of antioxidant defense system., B. I. Ognjanović, S. Z. Pavlović, S. D. Maletić, R. V. Žikić, A. Š. Štajn, R. M. Radojičić, Z. S. Saičić, V. M. Petrović., and Obsahuje bibliografii
Total superoxide dismutase (total SOD), copper zinc containing superoxide dismutase (CuZn SOD), and manganese superoxide dismutase (Mn SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione- S-transferase (GST) activities as well as ascorbic acid (AsA), and vitamin E (vit E) concentrations were analysed in the liver of rats exposed to cadmium (15 mg Cd/day/kg), selenium (7 fig Se/day/kg), and to cadmium + selenium (15 mg Cd + 7 ptg Se/day/kg), and in control animals. Cadmium caused a decrease of total SOD, Mn SOD, CAT and GSH-Px but an increase of GST activity in the liver of rats. Contrary to cadmium, selenium caused a significant increase of the activity of these enzymes except for GSH-Px. By concomitant exposure to both cadmium and selenium, the toxic effects of cadmium on the activity of mentioned enzymes we abolished. In all exposed groups, the activity of enzyme glutathione-S-transferase was enhanced, indicating its increased role in prevention of lipid peroxidation. Cadmium decreased the concentration of AsA and increased the concentration of vitamin E in the liver, while selenium increased the concentration of both vitamins. However, by concomitant administration of cadmium and selenium, these changes were diminished and tended to reach control values.