Vascular endothelial growth factor as early biomarker for hypoxia in Oreochromis niloticus

Aquatic pollution is a serious problem causing fish hypoxia. This study is conducted to assess the effects of environmental pollutants entering Lake Qaroun using vascular endothelial growth factor (VEGF) biomarker on Oreochromis niloticus. Water and fish samples were collected from contaminated sites to be compared with a reference relatively unpolluted site. Water physicochemical parameters, the oxidative stress biomarkers and histological studies of liver and gills were determined. Highly significant differences in water quality parameters were observed. Fish sampled from contaminated sites showed highly significant changes in oxidative stress and hypoxia‐related biomarkers compared to the reference site. These changes were accompanied by the existence of histological damages in liver and gill tissues. Moreover, there were differences in the banding pattern of fish serum proteins from the same sites. These results provide evidence that stress biomarkers and VEGF are useful for the assessment of hypoxia in aquatic environments influenced by multiple pollution sources.