Glyphosate-induced biochemical changes in female Cynopoecilus sp. inhabiting temporary wetlands

Glyphosate is Brazil's most widely used pesticide, often applied to different crops that may be close to temporary wetlands. This pesticide poses a threat to populations of annual killifish that live in these locations. Few studies have explored the toxicodynamics of pesticides in annual killifish. Here females of Cynopoecilus sp. at different development stages (young-adult and senile) are exposed to Roundup Original DI (R) herbicide (65, 130 and 260 mu g/L of acid equivalent of N-phosphomethyl glycine (glyphosate)) to analyze its impact on oxidative balance and lipoperoxidation, including superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and SOD/CAT ratio, as well as markers of intermediary metabolism such as total proteins (TPs), glycogen, and uric acid (UA). Senile females showed increased CAT and glutathione S-transferase activities and a decreased SOD/CAT ratio. Total protein and UA values were increased. Two-way ANOVA demonstrated correlations between age and different exposure groups for lipoperoxidation, SOD, CAT, GST, TPs, and UA, especially in senile females. Although it is not considered a target species, Cynopoecilus sp. suffers harmful effects from the interaction with this herbicide even at environmentally relevant concentrations. This impact was observed in senile females, which may result in reduced life cycle and reproduction quality.

Automated summary

Glyphosate, the most widely used pesticide in Brazil, poses a threat to the populations of annual killifish living in temporary wetlands. This study examined the effects of glyphosate exposure on oxidative balance, lipoperoxidation, and markers of intermediary metabolism in females of different developmental stages of Cynopoecilus sp. The results showed that even at environmentally relevant concentrations, glyphosate had harmful effects on senile females, potentially reducing their life cycle and reproduction quality.