Cognitive Enhancing Activity of Cynaroside Isolated from Lysimachia christinae on Memory Impairment Insulted by Scopolamine

The cognitive-enhancing effects of cynaroside, isolated from Lysimachia christinae, were evaluated in scopolamine-induced amnesic mice using the Morris water maze and passive avoidance tests. Cynaroside significantly improved scopolamine-induced reference memory impairment in the Morris water maze test. It also enhanced the mean escape latency, mean path length, and swimming movement. In the passive avoidance test, cynaroside significantly ameliorated scopolamine-induced amnesia, achieving approximately 70% of the level observed in normal control mice. Donepezil, an acetylcholinesterase inhibitor and widely used drug for Alzheimer’s disease treatment, served as a positive control. Cynaroside significantly inhibited acetylcholinesterase activity in the cortex and hippocampus, similar to the effects seen in mice treated with donepezil (1 mg/kg body weight, administered orally). These data suggest that cynaroside exerts potent cognitive-enhancing activity through anti-acetylcholinesterase mechanisms.