Impact of environmentally relevant concentration of benzophenone-3 on antioxidant enzymes, oxidative stress markers and morphology of gills in Danio rerio (Hamilton)

The current investigation intended to evaluate the effect of Benzophenone-3 (BP-3) at the environmentally relevant concentration (44 μg/L) in the gills of Danio rerio through evaluating oxidative stress markers and histopathological analysis. The adult Zebra fish was exposed to BP-3 at environmentally relevant concentration for 45 days. During the experimental period of 15, 30 and 45 days, lipid peroxidation markers like thiobarbituric acid reactive substances (TBARS) and Hydrogen peroxide (H2O2), antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx) and non-enzymatic glutathione (GSH) in the gill and histology of gill were analyzed. The activity of TBARS and H2O2 was found to be significantly higher meanwhile the activities of antioxidant enzymes viz., SOD, CAT, GPx and Glutathione (GSH) level were found to be significantly reduced in the gill of BP-3 treated fish for 30 and 45 days. Additionally, the morphology of gill also showed several abnormal changes in their morphology when compared to control. BP-3 exposure for 15 days elicited only mild alterations in the biochemical and histopathological variables when compared to 30 and 45 days exposure. Further, the values were also non-significant when compared to the control fish. These results demonstrated that the treatment of BP-3 at environmentally relevant concentration could prominently alter the respiratory physiology and metabolism of the gills of Danio rerio.