Assessment of Oxidative Stress and Histopathological Biomarkers in the Parablennius Incognitus Fish as Potential Contamination Indicators of the Bay of Sousse (Tunisia)

International audienceOxidative stress and histopathological biomarkers were investigated in the gills and liver of Parablennius incognitusfishes. Individuals sampled in the bay of Sousse were compared to fishes from a reference site, i.e. GhdamsiIsland (Tunisia). Severe biochemical and histological alterations were observed in fishes from Sousse bay andassociated with urban discharges contamination. Several tissue alterations were also observed in gills, particularlylamellar epithelium detachment, disorganization of pillar cells, and hypertrophy of chloride cells. In the liver wenoted particularly hypertrophy of hepatocytes, congestion and dilation of the central vein and sinusoid capillaries,pyknotic nucleus, and hepatic steatosis. The high reduction of superoxide dismutase and catalase activities in gillsand of superoxide dismutase and glutathione peroxidase activities in the liver of contaminated fishes may explainthe increase of lipoperoxidation in both organs of P. incognitus. The integrated biomarker response values found inindividuals from the contaminated site were in good agreement with alteration of physico-chemical parameters andwith the high level of Cd concentrations detected in water of the stressful place, i.e. the bay of Sousse. Oxidativestress and histopathological alterations were sensitive biomarkers to discriminate between fishes from the pollutedSousse bay site and those from the reference site, suggesting their potential utility in bio monitoring