Gomes_2026_Brain.Res_1893_150565

Paraquat (PQ) exposure induces oxidative stress, behavioral impairment, and monoaminergic dysfunction in experimental models. This study evaluated the effects of a complete aa (Euterpe oleracea) oil-loaded nanocapsule formulation (AON) on alterations associated with short-term PQ exposure in Drosophila melanogaster. A preliminary 5-day screening evaluated AON suspension concentrations from 0.2 % to 2.0 % (v/v), after which 0.2 % and 2.0 % were selected for a 5-day co-exposure experiment with 1.8 mM PQ. Each treatment was evaluated in five independent experimental runs, with one vial containing 50 flies constituting one biological replicate. PQ reduced survival, impaired climbing, and reduced open-field activity; it also increased reactive oxygen species and lipid peroxidation, altered catalase and superoxide dismutase activities, and affected acetylcholinesterase activity, dopamine, and serotonin. Co-treatment with the AON formulation was associated with higher survival and attenuation of climbing, oxidative, and selected neurochemical alterations relative to PQ alone. In the variance-robust analysis of open-field activity, the 0.2 % AON co-treatment differed from PQ alone, whereas the 2.0 % co-treatment did not. AON at 2.0 % alone also reduced open-field activity relative to the control. Under the present 5-day conditions, the complete AON formulation attenuated several PQ-associated endpoints; however, the study did not include non-encapsulated aa oil or empty nanocapsules and therefore does not establish an advantage of nanoencapsulation or the contribution of individual formulation components.