Effect of Tinospora cordifolia on learning and memory in normal and memory deficit rats

Objective: To study the effect of Tinospora cordifolia (Tc) on learning and memory in normal and cyclosporine induced memory deficit rats. Methods: Alcoholic and aqueous extracts of the whole plant of Tinospora cordifolia was administered orally for 15 days in two groups of rats. Cyclosporine 15, 25 mg/kg, i.p. was administered on alternate days for 10 days. Combination of cyclosporine 25 mg/kg, i.p. for 10 days and Tc alcoholic 200 mg/kg and Tc aqueous 100 mg/kg were administered in two different groups of rats. At the end of treatment, learning and memory was assessed using Hebb William maze and passive avoidance task. The locomotor activity was assessed using open field chamber. The immune status was studied using DNCB skin sensitivity test. Histopathological examination of hippocampus was done. Results: Both alcoholic and aqueous extracts of Tc produced a decrease in learning scores in Hebb William maze and retention memory indicating enhancement of learning and memory. However, cyclosporine at both the doses increased the learning scores in Hebb William maze and decrease in retention time in the passive avoidance task suggesting a memory deficit. The combination of cyclosporine and Tc produced a decrease in learning scores in Hebb William maze and increase latency in passive avoidance task compared to cyclosporine alone treated rats. The histopathological examination of hippocampus in cyclosporine treated rats showed neurodegenerative changes which were protected by the Tc. Conclusion: Tc enhances cognition (learning and memory) in normal rats. Cyclosporine induced memory deficit was successfully overcome by Tc.