Study Of Preventive And Therapeutic Effects Of Extract Of The Husk Of Xanthoceras Sorbifolia Bunge On Alzheimer's Disease

The preventive and therapeutic effects and mechanisms of extract of the husk of Xanthoceras sorbifolia Bunge on Alzheimer's disease were studied in this paper. In step-down test, ethanol extract of the husk of Xanthoceras sorbifolia Bunge (EXB), bunkanka saponins (BS) and ST-n-2 could markedly improve memory acquisition impairment induced by scopolamine and memory consolidation impairment induced by sodium nitrite. In radial arm maze task, EXB could obviously improve working memory and reference memory impairment induced by (+) MK-801, reduce the working time. The escape latency in water maze task and the numbers of error in step-through test were markedly decreased , the right reflect in water maze task and the escape latency in step-through test were increased in mice induced by intracerebroventricular injection (i.c.v.) Aβ (25-35). The escape latency in directional swimming task and swimming trial in working memory task were obviously shortened in Morris water maze and Percent alternation was increased in Y maze task in rats impaired by D-galactose and Aβ (25-35) and bilateral carotid common artery (BCCAO). The swimming time and distance in the target quadrant were prolonged and the numbers across the area of the platform were increased in probe test in rats with BCCAO. EXB increased superoxide dismutase (SOD) activity and decrease the content of malonic aldehyde (MDA) and acetylcholinesterase (AchE) in cerebrum of rats with BCCAO. EXB improved neurodegenerative changes and reduced the death of neurons in hippocampus in rats impaired by D-galactose and Aβ (25-35) and BCCAO. These results indicated that EXB significantly ameliorate learning and memory ability in model mice and rats with Alzheimer's disease. EXB has no effect on spontaneous activities in rats impaired by D-galactose and Aβ (25-35) and the effect on spontaneous activities in rats performed BCCAO has no dose-dependency and the model group has no obviously difference compared with the sham operated group, these results indicate that the effect on improving learning and memory of EXB has no relate to the excitability of cerebral cortex.