Effects of Shouwu-Yizhi capsule on learning and memory and the expressions of presenilin 1,β-amyloid precursor protein mRNAs in the hippocampus following cerebral ischemia reperfusion in rats

Abstract

Objective To investigate the effects of Shouwu-Yizhi capsule on learning and memory, and the expressions of presenilin 1（PS1）,β-amyloid precursor protein （APP） mRNAs in the hippocampus following cerebral ischemia reperfusion in rats. Methods Sprague–Dawley rats were randomly divided into a Shouwu-Yizhi group, a piracetam group, a model group, and a sham operation group with 20 rats in each group. Focal cerebral ischemia reperfusion model was induced by middle cerebral artery occlusion for 2 hours. Seven days after ischemia reperfusion, the rats in the Shouwu-Yizhi and piracetam groups were administered intragastrically Shouwu-Yizhi solution （52 mg/ml） and piracetam solution （28 mg/ml） for 28 days, both in dose of 1 ml/（100 g·d） for 28 days;and the rats in the model and sham operation groups were given intragastrically equivalent volumes of normal saline. Learning and memory were tested using the Morris water maze, and the expressions of PS1 and APP mRNAs were measured using real-time quantitative fluorescent PCR. Results Water maze test showed that the escape latency （12.98±0.70s vs. 9.43±0.78s） was significantly shorter, and the frequency of crossing platform （5.08±0.39 vs. 7.62±0.43） significantly lower in the model groupthan those in the sham operation group; the escape latency （9.77±0.58s vs. 12.98±0.70s） was significantly shorter and the frequency of crossing platform （7.40±0.44 vs. 5.08±0.39） significantly lower in the Shouwu-Yizhi group than those in the model group（all P〈0.01）. The expressions of PS1 （0.99±0.01 vs. 1.08± 0.03）and APP （1.06±0.03 vs. 1.12±0.04） mRNAs in the hippocampus in the Shouwu-Yizhi group were significantly decreased than those in the model group （P<0.05 or 0.01）. Conclusion Shouwu-Yizhi capsule may inhibit the expressions of PS1 and APP mRNAs in the hippocampus, and improve the learning and memory following cerebral ischemia reperfusion in rats. Key words: Brain ischemia; Presenilin-1; Amyloid beta-protein precursor; Gene expression; Learning; Memory; Shouwu-Yizhi eapsule