Abstract

Polygalae radix, the root of Polygala tenuifolia Willd, has been widely used as a drug for the treatment of amnesia, calm, convulsions, aging, physical weakness, abnormal intelligence, etc, in traditional Chinese medicine. Recent research indicated that Polygalae radix has the function of neural protection. Extractions and fractionation of Polygalae radix were used as effective compounds in this research, which mainly focused on the expression of Tau and BACE1, symbolic markers for Alzheimer's disease. The result indicated that Polygalae radix could reduce the expression of Tau and BACE1 after the treatment. This may improve and protect the normal function of the nervous system and reduce the harm of Alzheimer's disease. Amyloid plaques are characteristic features of Alzheimer’s disease and believed to be neurotoxic,which could be stained with Thioflavin S. The result indicated that the amyloid plaques were reduced significantly, this suggested that the symptom of Alzheimer’s disease was improved and the neurotoxic effect reduced. By Morris water maze tests, the study and memory ability of mice were improved after the treatment of Polygalae radix.

Key words:  Polygalae radix, dementia, Morris water maze tests, BACE-1, Tau, amyloid plaques, Thioflavin S staining.