Antioxidant response, CYP450 system, and histopathological changes in the liver of nitrobenzene-treated drakes.

Nitrobenzene (NB) has become an important pollutant in the environment, but its potential effects on non-target species such as drake remain unknown. In this study, we investigated the oxidative stress response, the CYP450 system and histopathological changes of the liver of NB-treated drakes for 40 d. Our results indicated that NB induced significant changes in antioxidant enzyme (SOD, CAT and GSH-Px) activities and the MDA content in the liver of the drakes. NB caused a condition-dependent increase in APND, EROD and ECOD isoenzyme activities and CYP450 content with increased exposure dose. Significant histological alternations were observed in the liver of NB-treated drakes and the pathological changes revealed tissue damage that was more severe with increasing of exposure dose. To our knowledge, this is the first study to report the chronic effects of NB on oxidative stress, the CYP450 system and histopathology in the drakes. These significant effects caused by NB reveal that these indices can be used as biomarker for monitoring NB as an environmental pollutant. Thus, future studies are needed to fully understand the exact mechanisms of these findings.