Persistent impairment of gonadal development in rare minnow (Gobiocypris rarus) after chronic exposure to chlorinated polyfluorinated ether sulfonate

The delayed and persistent adverse effects caused by developmental exposure to per-and poly-fluorinated substances are of significant concern. Juvenile rare minnows (Gobiocypris rarus), were exposed to chlorinated polyfluoroalkyl ether sulfonate (Cl-PFESA) at measured medium concentrations of 86.5 mu g/L, 162 mu g/L and 329 mu g/L, for 4 weeks followed by 12 weeks of depuration. After 4 weeks of exposure, the body weight and length of the juvenile fish were increased compared to controls. Gene expression of gnrh3, lh beta, and cyp19a was decreased, and ar and er alpha were upregulated. Transcriptomic analysis revealed enrichment of multiple pathways related to gonadal development. After 12 weeks of depuration, the gonadosomatic indices were decreased in female fish in a concentration-dependent manner, with a significant decrease to 59% of control in 329 mu g/L group. Histological analysis found increasing numbers of degenerating oocytes and perinucleolar oocytes, and decreasing numbers of mature vitellogenic oocytes in female fish treated by Cl-PFESA. Enlarged interstitial space of the testis was observed in the exposed male fish. Gene expression levels of gnrh3, lh beta, ar, er alpha, and vtg were upregulated in the adult fish. Chronic developmental exposure to Cl-PFESA caused persistent effects on gonadal development of fish, highlighting the necessity of a comprehensive ecological risk assessment.

Automated summary

The persistent adverse effects of developmental exposure to Cl-PFESA on fish's gonadal development are of significant concern. After 4 weeks of exposure, the body weight and length of juvenile fish increased, while gene expression of gnrh3, lh beta, and cyp19a decreased and ar and er alpha were upregulated. After 12 weeks of depuration, the gonadosomatic indices decreased in female fish, with increasing numbers of degenerating oocytes and perinucleolar oocytes, and decreasing numbers of mature vitellogenic oocytes. The exposed male fish showed an enlarged interstitial space of the testis, and gene expression levels of gnrh3, lh beta, ar, er alpha, and vtg were upregulated in the adult fish.