Quercetin and rutin prevent scopolamine-induced memory impairment in zebrafish

Demographic aging gives rise to a growing population with age-associated behavioral and cognitive deficits that may be associated at least partially to the increasing prevalence of neurodegenerative disorders, such as Alzheimer's disease (AD). In this disease, it has been observed a decrease in the cholinergic system, which is crucial to memory formation. Scopolamine-induced amnesic effect, through the disruption of the cholinergic neurotransmission, is one of the approaches used to investigate the mechanisms involved in cognitive impairment observed in AD. The aim of our study was to investigate the potential protective role of quercetin and rutin against scopolamine-induced inhibitory avoidance memory deficits in zebrafish. Scopolamine (200 μM dissolved in the tank water for 1 h) given pre-training hindered memory formation while both quercetin and rutin pretreatments (50 mg/kg, single injection, i.p.) prevented the scopolamine-induced amnesia. None of the compounds affected zebrafish general locomotor activity. Together, these results contribute to the increase of the knowledge about plant compounds applicability as medicines to prevent and treat neurodegenerative diseases, like Alzheimer's disease.

Research highlights▶ Scopolamine induces a memory deficit in zebrafish in the inhibitory avoidance task. ▶ Pre-treatment with quercetin or rutin prevents scopolamine-induced memory impairment. ▶ Neither scopolamine nor quercetin or rutin treatment affected zebrafish locomotion.