Enzymatic and histopathologic biomarkers in the flatfish Euryglossa orientalis from the northwestern Persian Gulf

Most of the chemicals in the petrochemical sewages cause oxidative stress in marine organisms. Antioxidant enzymes (catalase (CAT) and superoxide dismutase (SOD)) as biomarkers of oxidative stress and liver histopathological alterations were investigated in the current study to evaluate the toxic effects of petrochemical pollutions in flatfish, Euryglossa orientalis. The enzymatic and histopathological changes were assessed in the liver of E. orientalis from Khowr-e Jafari (one of the creeks from Khowr-e Musa estuary) and Sajafi harbor as polluted and clean areas, respectively. A significant increase in the antioxidant enzyme activities was observed in response to aquatic pollutions of Khowr-e Jafari. Liver lesions were diagnosed and categorized using standard methods. The results of histopathological examinations showed more lesion scores in the fish from Khowr-e Jafari. Various histopathological changes including hepatocyte degeneration, inflammatory lesions, peliosis hepatis and pancreatic acinar cell adenoma, and increase in the number of pigmented macrophage aggregates were observed in the fish from polluted site. It is suggested that activities of CAT and SOD along with semi-quantitative histopathologic analysis of E. orientalis can be used for biomonitoring programs in Persian Gulf.