Cognitive-enhancing effects of hydrolysate of polygalasaponin in SAMP8 mice
Pan Xu, Shu-ping Xu, Ke-zhu Wang, Cong Lu, Hong-xia Zhang, Rui-le Pan, Chang Qi, Yan-yan Yang, Ying-hui Li, Xin-min Liu
Research Center of Pharmacology and Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, China; Division of Stem Cell Regulation and Application, Hunan University of Chinese Medicine, Changsha 410208, China; Science and Technology on Human Factors Engineering Laboratory, Astronaut Centre of China, Beijing 100193, China
liuxinmin@hotmail.com
Abstract: Objectives: The aim of the study is to evaluate the cognitive-enhancing effects of hydrolysate of polygalasaponin (HPS) on senescence accelerate mouse P8 (SAMP8) mice, an effective Alzheimer’s disease (AD) model, and to research the relevant mechanisms. Methods: The cognitive-enhancing effects of HPS on SAMP8 mice were assessed using Morris water maze (MWM) and step-through passive avoidance tests. Then N-methyl-D-aspartate (NMDA) receptor subunit expression for both the cortex and hippocampus of mice was observed using Western blotting. Results: HPS (25 and 50 mg/kg) improved the escape rate and decreased the escape latency and time spent in the target quadrant for the SAMP8 mice in the MWM after oral administration of HPS for 10 d. Moreover, it decreased error times in the passive avoidance tests. Western blotting showed that HPS was able to reverse the levels of NMDAR1 and NMDAR2B expression in the cortex or hippocampus of model mice. Conclusions: The present study suggested that HPS can improve cognitive deficits in SAMP8 mice, and this mechanism might be associated with NMDA receptor (NMDAR)-related pathways.
Key words: Cognitive improvement, Hydrolysate of polygalasaponin, SAMP8 mice