Induction of oxidative stress in Clarias gariepinus from Eleyele River in Nigeria

This study evaluated some markers of oxidative stress in the organs of African Catfish, Clarias gariepinus from Eleyele River in Oyo State, Nigeria. Clarias gariepinus (250 g-400 g) were collected from Eleyele River (a suspected polluted River) and Clarias gariepinus from a clean fish farm (Durantee fisheries) were used as the control. Levels of Malondialdehyde (index of lipid peroxidation), Glutathione (GSH) and activities of antioxidant enzymesSuperoxide dismutase (SOD), Catalase and Glutathione-STransferase (GST) were evaluated in the liver, kidney and gills of the fish. From the results, there were significant (p<0.001) increases in malondialdehyde and GSH levels in the liver, kidney and gills of Clarias gariepinus from Eleyele River compared with control. The activity of GST increased significantly (p<0.05; p<0.001) in the liver and kidney of fish from Eleyele River compared with control. There was a significant decrease (p<0.05; p<0.001) in SOD activity in all the organs of Clarias gariepinus from Eleyele River compared with conrol and also a significant (p<0.001) decrease in catalase activity in the gills and kidney of the fish but catalase activity increased in the liver. Increase in lipid peroxidation and alterations in antioxidant status in Clarias gariepinus from Eleyele River show that the fish were under oxidative stress. These suggest that the River is polluted probably as a result of various wastes frequently discharged into the River. This could pose serious health risks to consumers of water and aquatic organisms from the River.