Assessment Of The Neurotoxicity Of Ethanol Leaf Extract Of Ficus Benjamina (Weeping Fig) On Brain Of Wistar Rats

Abstract

Ficus benjamina has been proven to have medicinal potential, especially in alleviating some brain pathologies but there are few works on its neurotoxic effect. This study investigated the acute toxicity and effect of ethanol crude leaf extract of Ficus benjamina on the histology of some parts of the brain. Twenty-nine (29) Wistar rats weighing 123g-190g were used for the study. LD₅₀ was determined with nine (9) rats using Lorke’s method. Twenty (20) rats were divided into four (4) groups of 5 animals each. The control group was administered water and feed. Low dose (500 mg/kg), medium dose (1000 mg/kg), and high dose (1500 mg/kg) of extract were administered for twenty-one (21) days. On the 21^st day, all the animals were weighed and sacrificed and their brains were harvested and processed histologically by the formalin-fixed-paraffin wax embedding method. The tissue blocks were sectioned and stained using haematoxylin and eosin, Periodic acid Schiff, and GFAP (glial fibrillary acidic protein). The results showed that the LD₅₀ was ≤5000 mg/kg. There was no statistical significant difference in the body weights of the animals before and after the experiment (p=). Histopathological changes showed normal histology of cells in the choroid plexus, hippocampal CA3 area, and cerebral frontal cortex, with normal glycogen and astrocytes in the control. The low-dose group had mild reactive astrogliosis. There was mild atrophy, vacuolation, and mild reactive astrogliosis in the medium-dose group. The high-dose group had marked hypertrophy/hyperplasia, blood vessel dilation, vacuolation, necrosis, and mild reactive astrogliosis. The results suggest that prolonged consumption of the medium and high doses of the leaf extract of Ficus benjamina may cause marked neurotoxicity. The low dose is safer for administration.