Assessment of neurotoxicity and oxidative stress induced by environmentally persistent pharmaceutical pollutants

The study aimed to examine the possible impact of environmentally persistent pharmaceutical pollutants at environmentally relevant concentrations. Intriguingly, the Novel Tank Behavior Test did not reveal significant differences in anxiety-related behaviors. However, the Social Interaction Test unveiled a substantial reduction in social interaction, particularly notable in zebrafish treated with carbamazepine (CBZ). Furthermore, the Mirror Biting Behavior Test illustrated a complex picture, with CBZ inducing heightened aggression while Metformin (MET) treatment resulted in reduced aggression. The study also delved into light and dark zone preferences, revealing that CBZ-treated fish spent significantly more time in both zones, whereas MET-treated fish exhibited a preference for the dark zone. These behavioral findings were complemented by biochemical analyses, which unveiled gender-specific variations in acetylcholinesterase (AChE) activity. Males consistently exhibited increased AChE activity across all treatment groups, while females displayed unique responses, with TMP and MET-treated females showing increases and CBZ-treated females exhibiting a decrease. Additionally, Superoxide Dismutase (SOD), Catalase (CAT), and Glutathione S-Transferase (GST) activities exhibited intricate responses to pharmaceutical treatments, with variations based on gender and specific pharmaceutical agents used. While the 7-day exposure duration and environmentally relevant concentrations used in this study offer valuable insights into acute effects, future research with longer exposure durations may provide insights into chronic consequences in aquatic ecosystems.