Comparative study of the effect of <i>Ginkgo biloba</i> extract and vitamin c on lead induced hippocampal toxicity in adult male Wistar rats

Abstract

Pharmaceutical and industrial preparations contain lead and exposure to it has been associated to be the cause of neurodegenerative diseases. Therefore, in this current study, we investigated the comparative neuroprotective potentials of graded dose of Ginkgo biloba and Vitamin C in lead-induced alterations in the hippocampus of Wistar rats. Six groups of six adult Wistar rats each contained 36 animals in total. Group A served as the control and received normal tap water. Group B received 100mg/kg body weight of lead only. Group C received 100mg/kg body weight of lead and 200mg/kg body weight of Ginkgo biloba. Group D received 100mg/kg of lead and 250mg/kg of Ginkgo biloba. Group E received 100mg/kg of lead and 1192mg/kg of vitamin C, Group F received 200mg/kg of Ginkgo biloba only. For twenty-one days, all administrations were done orally. The Data were expressed as mean ± SEM and were analyzed. Statistical significance between the means was analyzed using one-way analysis of variance (ANOVA) followed Tukey post-hoc test. P-value < 0.05 was considered statistically significant. There is statistically significant (P= 0.0004) reduction in the percentage body/weight (0.6217±0.05566) of the Vitamin C treated group when compared to the control. The Biochemical analysis revealed that there is a statistically significant (P<0.0001) reduction in the concentration of superoxide dismutase, SOD (25.00 ± 0.6952) and catalase, CAT (25.00 ± 0.2728) in the lead only group when compared with the control. Additionally, treatment with Vitamin C causes a statistically significant (P<0.0001) increase (30.00±0.8021) in the CAT level when compared to the lead group. The histology of the dendate gyrus in lead only group shows distortion with fragmented hippocampal layer. Groups that were treated with Ginkgo biloba and Vitamin C shows gradually normalized cellular assortment of hippocampal layers. However, the group treated with Ginkgo biloba has more healthy cells. Also, the histology of the regions of the hippocampus in lead only group reveals several pyknotic changes, including disorganized pyramidal and grandular neurons within severed fragmented layers. Treatment with Ginkgo biloba and Vitamin C normalized DG architecture with cellular features that is similar to that of the control groups. Furthermore, the group treated with Ginkgo biloba appears healthier. Similarly, treatment with Ginkgo biloba and Vitamin C prevents degeneration of pyramidal neurons and shows pyramidal neurons with normal cell bodies with dendritic and axonal processes. This present study shows that Ginkgo biloba and Vitamin C have similar neuroprotective effects on lead-induced neurotocity in Wistar rats in a dose-dependent manner, with Ginkgo biloba being more effective.