Search

Propylparaben (PrP) is widely applied in food, pharmaceuticals and personal care products as preservatives, and the extensive usage of PrP has posed potential threat to aquatic ecosystem. In this study, wild-sourced female mosquitofish were treated with different concentrations of PrP (0.15, 6.0 and 240.0 µg⋅L-1) for 4 d and 16 d respectively. The tissue sections as well as mRNA expression changes of antioxidant and endocrine-related genes from the brain, gills and liver, were analyzed to investigate the toxicological effects of PrP on mosquitofish. The results showed that different PrP exposure time resulted in varying degrees of damage to the gills and liver of mosquitofish. With the extension of exposure time, the expression of antioxidant-related genes in the brain was up-regulated, whereas the expression of antioxidant-related genes in the gills, as well as cat and cyp4501a genes in the liver, were down-regulated, and the oxidative stress response in the gills and liver gradually weakened. When female mosquitofish were exposed to PrP for 4 d, the endocrine-related genes in the brain increased firstly and then decreased with increasing PrP dose, while in the 16-d-PrP-exposure groups, the genes showed an increased trend compared with that of the control. After 4 d of PrP exposure, a significant difference was observed in the expression of the vtgB gene within liver tissues between the 0.15 µg⋅L-1 PrP group and the control group, as well as in the expression of the arβ gene within liver tissues between the 240.0 µg⋅L-1 PrP group and the control group; however, no significant differences were found in other endocrine-related genes among different PrP groups and the control group. When the exposure time was extended to 16 d, the expression of era, erβ, arα, arβ, vtgC and vtgB genes in the liver was all up-regulated in the three treatment groups, indicating that PrP had estrogenic effects on mosquitofish. This study revealed the toxic damage, oxidative stress and endocrine disrupting effects of PrP on mosquitofish, through the phenotypic variations in tissues and changes in mRNA expression of key functional genes, which will provide a scientific basis for the potential health risk assessment and safe application of PrP. [ABSTRACT FROM AUTHOR]