Ameliorating effects of constituents from Cortex Acanthopanacis Radicis on memory impairment in mice induced by scopolamine

Abstract

ObjectiveTo investigate the effects of active constituents extracted from Cortex Acanthopanacis Radicison improving the impaired memory in mice models. MethodsThe mice models of memory impairment were established using scopolamine. Ameliorating effects of the fractions and constituents on scopolamine-induced memory impairment in vivo were investigated using passive avoidance and Morris water-maze task tests, and their anti-acetylcholinesterase (AChE) and antioxidant activities in vitro examined. The isolation of constituents was performed by chromatographic methods and their structures were identified on the basis of instrumental analysis. ResultsAmong the fractions tested, ethylacetate fraction exhibited the anti-AChE activity (25.83% ± 0.23%) properly and excellent 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide anion scavenging capacity (87.50% ± 0.83% and 60.22% ± 0.43%, respectively). However, the methylene chloride fraction was much more active than the ethylacetate fraction in the passive avoidance task test (167.5% increase of step-through latency time) and Morris water-maze task test (33.3% decrease of escape latency time). Four constituents, β-sitosterol, stigmasterol, sesamin, and hyperin were isolated from the methylene chloride fraction, among them, hyperin showed anti-acetylcholinesterase and anti-oxidant activities remarkably. Moreover, hyperin exerted a potent effect (146±38) s on memory improvement in terms of passive avoidance task test compared with the reference compound tacrine (162±43) s at a dose of 2.5 mg/kg. ConclusionHyperin, a flavonoid glucoside isolated from Cortex Acanthopanacis Radicis, inhibited AChE activity and potently ameliorated scopolamine-induced memory impairment, and its action may be partially mediated by the acetylcholine-enhancing cholinergic nervous system.