The extract of Cynomorium songaricum improves the memory disorder in rats potentially through the regulation of CREB pathway

Alzheimer's disease (AD) is a kind of degenerative disease which is characterized by progressive intelligence deterioration. It has been demonstrated that the pCREB plays an important role to modulate the transcription of various target genes such as NGF, which participates in the processes of synapse plasticity and long term memory. Stems of Cynomorium songaricum have been used to treat neuronal disease traditionally in China for periods. In this study, we investigated the protective effects of the extract of C. songaricum against Aß_{1 – 42} induced injury in vivo by determination of the learning and memory ability as well as expressions of pCREB and NGF. In this study, 40 SD rats were randomly divided into 4 groups: control, model and treatment groups with donepezil hydrochloride and extract with C. songaricum by intragastric administration. The AD model was established by injection of agglomerated Aß_{1 – 42} in rat 's hippocampus. After treating 28 days, the Y-maze was used to test the learning and memory ability, immunohistochemistry and western blotting were used to test the expression changes of pCREB and NGF.

The results of Y-maze showed that the total reaction time and error number of the treatment group with C. Songaricum (23.5 ± 3.35 min,10.1 ± 2.46 respectively) were significantly lower than model group (31.44 ± 5.93,16.11 ± 3.74). Immunobistochemistry and western blotting results showed the the extract of C. songaricum increased the expressions of pCREB and NGF comparing with the model group. Thus the extract of the C. songaricum might improve the learning and memory ability in AD rats induced by Aß_{1 – 42} partly due to regulate the expression of pCREB and its downstream target NGF.