Eucalyptus alba Reinw Ex. Blume (Myrtaceae) extracts mitigate behavioral changes, neurohistopathological alterations, and hypothalamus-pituitary-adrenal axis dysregulation following prenatal stress in a rat model

Abstract Background Management as well as treatment of antenatal stress is a global concern and today, people tend to use alternative treatment through medicinal plants like Eucalyptus alba (E. alba) . Objective This study investigates the potential of aqueous and ethanol leaf extracts of E. alba in management of the impact of antenatal stress in young rats. Methodology Phytochemistry of the leaf extracts was conducted and forty-five gravid albino rats randomly assigned into 9 groups. All but group one was induced with stress before receiving treatments. Group 2 received 5mL/kg of distilled water; group 3 received 1 mg/kg of diazepam. Groups 4 through 9 received aqueous and ethanol extracts of E. alba (100 mg/kg, 200 mg/kg and 400 mg/kg respectively) until delivery. After 21 days, litters were subjected to behavioral tests, followed by sacrifice, then hormone levels evaluation and brain histological analysis conducted. Results Flavonoids, saponins, phenols and tannins were present in both extracts. Motor dysfunction, anxiogenic like and depressive like behaviors were alleviated by both extracts. The plant extracts also antagonized the stress induced increase in corticotropin-releasing hormone, adrenocorticotropic hormone and corticosterone production. Histological analysis of the different structures of the brain cortex, hippocampal CA1 and CA3 regions, gyrus and the amygdala confirmed the obtained results as alteration of structures were prevented by both plant extracts. Conclusion Eucalyptus alba extracts exhibited neuroprotective properties against prenatal stress by protecting brain damages, maintaining the hypothalamic-pituitary-adrenal axis integrity and consequently the level of hormones production by the axis.