Protective Effects Of Cynanchum Auriculatum Extract On Mice With Vascular Dementia

Vascular dementia (VD) is another common cause of dementia besides Alzheimer's disease (AD) in the world; it is also a frequently encountered disease for aged people in our country. With the growth of the aged population, increasingly importance has been attached to the study of VD in the world.The main origin of Baishouwu in Binhai County is the root tuber of the Cynanchum auriculatum Royle ex Wight. It has been reported that the Cynanchum auriculatum Royle ex Wight exhibited several pharmacological activities, including anti-tumor, immunocompetence enhancement, anti-oxidation and so on. In this paper, a VD animal model was established through repeated cerebral ischemia-reperfusion in mice with tail bleeding hypotension. This model was used to evaluate the protective effects of extract from Cynanchum auriculatum on mice with vascular dementia.The roots of Cynanchum auriculatum was extracted by ethanol then purified using macroporous resin D101. The main components of the extract were C21 steroidal glycoside, and the measurable content of the C21 steroidal glycoside was nearly 65%. This extract was used to intragastric administrate mice for 24 days consecutively, and then the VD animal model was established on the 15th day. The test of Morris water-maze showed that the extract elevated the learning and memory abilities of mice.Further research showed that the extract of Cynanchum auriculatum contained several protective effects on mice in different aspects:①alleviating the cerebral edema;②reducing the content of monoamine oxidase (MAO);③m aintaining the activity of acetylcholine esterase(AchE) in brain;④d ebasing the concentration of glutamic acid (Glu), one of the excitative amino acids in brain;⑤maintaining the structure and the quantity of neurocyte after modeling;⑥r estraining the over-expression of N–methyl-D-aspartic acid receptor (NMDAR) in brain;⑦enhancing the aerotolerant ability;⑧enhancing the abilities of anti-oxidation and free-radical scavenger.