The effects of imidacloprid on 8-hydroxy-2-deoxyguanosine (8-OHdG) and antioxidant parameters in gill and liver tissues in rainbow trout

In this research, the biochemical effects of imidacloprid, which has been increasingly used in the recent years and is a topic of discussions mostly due to its effect on non-target organism, on rainbow trout (Oncorhynchus mykiss) were studied. Three different concentrations (5 mg/L, 10 mg/ L and 20 mg/L) of the imidacloprid, which is a neonicotinoid, were routinely exposed to rainbow trout for 21 days. Liver and gill tissue samples were taken from fish exposed to imidacloprid at the end of the application period. Antioxidant enzymes, malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHDG) were studied in the samples taken. The levels of superoxide dismutase, catalase and glutathione peroxidase (SOD, CAT, GPx) were determined in antioxidant enzymes by spectrophotometric methods. In the experimental groups in which different doses were applied, it was observed that the antioxidant enzyme levels increased as the concentration increased. In 5 mg/L experimental group, it was determined that CAT values and liver GPx and SOD levels increased compared to those in the control group. It was found that there were significant increases between 5 mg/L and 10 mg/L dose groups in terms of MDA, 8-OHdG, liver GPx-SOD and gill CAT-GPx enzyme activities (p<0.05). High increases in all antioxidant enzyme levels and deterioration were observed in liver and gill tissues taken from fish exposed to 20 mg/L dose imidacloprid. 8-OHdG and MDA levels significantly increased in parallel with the increase in the dose (p <0.05).