Exploring the nootropic effect of Juniperus recurva extract: Possible involvement of acetylcholinesterase inhibition

Abstract

Background: Currently, available therapy for the treatment of memory impairment is far from satisfactory. Therefore, the agents of natural origin may serve as potential therapies. Objective: The present study was designed to evaluate the memory-enhancing effect of Juniperus recurva extract. Materials and Methods: The methanol extract of J. recurva was prepared by Soxhlet extraction and characterized by high-performance liquid chromatography (HPLC). The in vitro antioxidant activity of the extract was corroborated by diphenyl picryl hydrazine scavenging, nitric oxide scavenging, metal chelating, and reducing power activity. Memory impairment was induced by the administration of scopolamine (1 mg/kg i.p) on 3 consecutive days to mice and assessment of memory acquisition and memory retention was done using Morris water maze test, passive avoidance test, elevated plus maze test, and light and dark box test, motor coordination was evaluated using the rotarod test and inclined plane test; and depression was evaluated by forced swim test. Serum acetylcholinesterase (AChE) activity was quantified by Ellman’s method. Results: The HPLC analysis of J. recurva extract revealed gallic acid as a prominent peak. The extract was found to have an excellent antioxidant effect in all the tests employed. The in vivo studies revealed memory enhancing and improved motor coordination activity of the extract in mice. Serum AChE activity was decreased on the administration of the extract. Conclusion: The inhibition of the AChE enzyme contributes to the memory-enhancing activity of J. recurva extract.