Neurotoxicity and Behavioral Alterations Following Subchronic Administration of Aqueous Extract of Erythrophleum Ivorense Stem Bark in Mice.

Introduction: Erythrophleum Ivorense (EI) is a tree found across tropical Africa. The bark of EI is widely used as hunting poisons for animals and ordeal poison in humans. Eating this plant causes paralysis, respiratory distress, and amnesia. In folklore, these behavioral changes have been attributed to guilt in victims; nonetheless, no scientific evidence supports this claim. Thus, the mechanism of neurotoxicity and behavioral alteration of this plant should be investigated.

Methods: A total of 48 BALB/c male mice were randomly divided into four groups. The three experimental groups were administered an aqueous extract of EI in a single daily dose of 5, 10, and 15 mg/kg bodyweight for 28 days, while the control group received distilled water. Afterward, the motor coordination, learning, memory, and grip strength of the mice were accessed with wire grip, Morris water maze, and inverted wire mesh grid grip tests. Histological staining of brain sections was also carried out.

Results: At all tested doses, the aqueous extract of EI caused a significant reduction in hanging latency, significantly increased escape latency, and decreased duration of the target platform in the Morris water maze test compared to control. Reduced grip strength was also observed in the test groups compared to the control. Histology revealed dysmorphic and disoriented Purkinje cells and loss of this cell layer of the cerebellum.

Conclusion: Erythrophleum ivorense administration altered motor coordination, learning and memory, and grip strength in mice dose-dependently. It also caused disruption of granule cells layer, loss of Purkinje cells, and altered cerebellar anatomy leading to motor deficits in mice.