XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Posters
119.
OXIDATIVE STRESS IN TURKEYS CAUSED BY CHRONIC CADMIUM
EXPOSURE
Anna Sobeková 1 , Katarína Holovská 2 and Peter Javorský 3
1
Department of Chemistry, Biochemistry and Biophysics UVLF in Košice,
2
Department of Anatomy, Histology and Physiology UVLF in Košice,
3
Institute of Animal Physiology SAV Košice
Heavy metals can cause oxidative stress by increasing the formation of reactive oxygen
species (ROS), which render antioxidants incapable of defence against growing amounts
of free radicals. The alterations of ROS scavenging enzyme activities are the consequences
of this effect. The effect of single Cd and Cd+Zn on the antioxidant enzymes
(SOD-superoxide dismutase, GPx-glutathione peroxidise, GR-glutathione reductase,
GST-glutathione-S-transferase) and the content of thiobarbituric acid reactive species
(TBARS) was evaluated in parenchymal tissues (liver, kidney) from turkeys.
In the liver, the specific activity of SOD was significantly increased in Cd group. Mitochondria
try to decrease intracellular ROS levels by decreasing to consume of oxygen via formation
of „extremely swollen mitochondria“. Ultrastructural changes were confirmed by
electron microscopy. TBARS values were not changed in Cd group. Antioxidant defence
system were able to protect the hepatocytes against oxidative damage.
Activity of SOD was significantly decreased in the kidney. Cadmium evoked the increase
of activity of another determined antioxidant enzymes (GSHPx, GR, GST). Higher TBARS
values indicate the oxidative stress in this organ. Zinc co-administration shows protective
effect in both observed tissues.
The alterations in the activities of antioxidant defence system and increased TBARS
values showed that toxic effect of cadmium is not only in the high thiol group affinity,
but also in ROS production.
244 XXII. Biochemistry Congress, Martin