Evaluation of nootropic activity of Curcuma longa leaves in diazepam and scopolamine-induced amnesic mice and rats

Abstract
Background: The present study was undertaken to assess the nootropic activity of hydroalcoholic extract of Curcuma longa leaves (HAECL) in diazepam-induced amnesia in mice using Morris water maze method and scopolamine-induced amnesia in rats by using elevated plus maze behavioral paradigm and its effect on acetylcholinesterase (AChE) and reduced glutathione (GSH) level were carried out. Methods: Amnesia was induced by administration of diazepam (1 mg/kg i.p.) and scopolamine (0.4 mg/kg i.p.) and treatment groups received HAECL (200 and 400 mg/kg p.o) for 14 and 10 days in scopolamine and diazepam-induced amnesia model, respectively. The extent of improvement in memory was measured by behavioral paradigm. Finally, animals were sacrificed, and the whole brain was isolated for estimation of concentration of AChE and reduced GSH levels. Results: The oral treatment with HAECL with a dose 400 mg/kg has shown an enhancement in the memory function compared to 200 mg/kg. Conclusion: This could be by inhibiting the levels of cholinesterase concentration of enzyme and thereby increasing the concentration of acetylcholine level in brain and improving cognition-memory performance.Key words: Hydroalcoholic extract of Curcuma longa leaves, Piracetam, Scopolamine, Diazepam, Morris water maze, Elevated plus maze, Acetylcholinesterase