ANTIOXIDANT ENZYMES AND LIPID PEROXIDATION RESPONSES IN TWO SIZES OF AFRICAN CATFISH (Clarias gariepinus) EXPOSED TO SODIUM BICARBONATE

Abstract

Some antioxidant enzymes which include catalase (CAT), Superoxide dismutase (SOD), Glutathione-S- Transferase (GST) and Lipid peroxidation (LPO) in the plasma of juvenile and adult life stages of Clarias gariepinus was investigated in this study. A total of 150 Clarias gariepinus which comprised of 75 juvenile (mean length 26.75± 5.98 and mean weight 265.06± 17.24) and 75 adult (mean length 46.88± 12.07 and mean weight 788.91± 45.70) were sourced from the center.  After exposing the fish to different concentrations (0.00 - control; 50, 100, 150, and 200 mg/L) of sodium bicarbonate solution, blood samples were collected and the antioxidant enzymes activities were measured. Results from the analysis showed that the activities of SOD, LPO and GST increased significantly (P<0.05), while the values of CAT reduced in both sizes when compared to the control. Results indicate concentration dependent activation of oxidative stress and subsequent alterations in the activities of these antioxidant enzymes, which were more pronounced in the juveniles than the adult fish. The result from this study, therefore suggests that sodium bicarbonate may induce oxidative stress, which is capable of overwhelming the antioxidant system of this species, especially at higher concentrations of exposure to the chemicals.