目的研究生慧汤对APP/PS1（β-amyloid precursor protein/presenilin 1246E）小鼠海马内β淀粉样前体蛋白（Amyloid precursor protein，APP）代谢产物昼夜表达的影响。方法 将56只雄性APP/PS1双转基因痴呆模型小鼠随机分为4组，分别为：痴呆模型组、褪黑素治疗组（0.78 mg·kg^-1·d^-1）、生慧汤高剂量组（27.0 g·kg^-1·d^-1）、生慧汤低剂量组（13.5 g·kg^-1·d^-1），每组14只；对照组为14只雄性C57BL/6J小鼠，连续给药30天。采用Morris水迷宫检测小鼠学习记忆能力，采用酶联免疫吸附检测（ELISA）检测不同时间段取出的海马组织sAPPα含量。对海马β淀粉样蛋白_1-40、β淀粉样蛋白_1-42表达进行免疫印迹分析。免疫组化（IHC）检测海马CA1区Aβ_1-40蛋白的表达。结果 Morris水迷宫结果表明，与对照组相比，模型组上平台潜伏期明显延长、穿越平台次数明显减少（P<0.01）；与模型组相比，生慧汤不同剂量组上平台潜伏期明显缩短（P<0.01、P<0.05），穿越平台次数明显增加（P<0.05）。ELISA结果表明，与对照组相比，模型组的sAPPα总量、各时间段（12：00、24：00）sAPPα含量明显减少（P<0.01）；与模型组相比，生慧汤不同剂量组sAPPα总量明显增多（P<0.01、P<0.05），生慧汤高剂量组仅能增加12：00 sAPPα含量（P<0.01），生慧汤低剂量组仅能增加24：00 sAPPα含量（P<0.05）。对照组sAPPα含量具有明显昼夜差异（P<0.01）。模型组sAPPα含量的昼夜差异性消失（P>0.05）。生慧汤高剂量组sAPPα含量具有昼夜差异（P<0.01），生慧汤低剂量组sAPPα含量不具有昼夜差异（P>0.05）。Western blot结果显示，与对照组相比，模型组Aβ_1-40、Aβ_1-42蛋白表达明显增加（P<0.01）；与模型组相比，生慧汤高剂量组Aβ_1-40、Aβ_1-42蛋白表达减少（P<0.05、P<0.01）；生慧汤低剂量组仅能减少Aβ_1-40蛋白的表达（P<0.05），对Aβ_1-42蛋白表达无影响（P>0.05）。免疫组化结果表明，与对照组相比，模型组Aβ_1-40表达明显增加（P<0.01）；与模型组相比，生慧汤不同剂量组Aβ_1-40表达不同程度减少（P<0.01、P<0.05）。结论 生慧汤能够改善5月龄APP/PS1阿尔茨海默病模型小鼠的学习记忆障碍，其机制可能与恢复海马内APP代谢产物sAPPα的昼夜节律性表达、从而减少Aβ的沉积有关。

Objective To study the effect of Shenghui decoction on the diurnal expression of amyloid precursor protein (APP) metabolites in the hippocampus of APP/PS1 mice.Methods Fifty-six male APP/PS1 double transgenic mice with dementia were randomly divided into 4 groups, dementia model group, melatonin treatment group (0.78 mg·kg^-1·d^-1), high dose group of Shenghui decoction (27.0 g·kg^-1·d^-1)and low dose group of Shenghui decoction(13.5 g·kg^-1·d^-1). 14 male C57BL/6J mice in control group, 30 days of continuous administration. The learning and memory ability of mice was tested by Morris water maze. The level of sAPPα in different time was detected by enzyme-linked immunosorbent assay (ELISA). The expression of β amyloid protein_1-40 and β amyloid protein_1-42 in hippocampus were analyzed by western blotting. The expression of βamyloid protein_1-40 in hippocampus CA1 region was detected by immunohistochemistry (IHC).Results The results of Morris water maze showed that compared with the control group, the latency of the platform in the model group was significantly prolonged and the number of crossing the platform was significantly reduced (P<0.01). Compared with the model group, the incubation period of the platform was significantly shortened (P<0.01, P<0.05), and the number of crossing the platform was significantly increased (P<0.05) in different dose groups of Shenghui decoction. ELISA results showed that compared with the control group, the total amount of sAPPα and the sAPPα content at each time period (12:00 and 24:00) were significantly reduced in the model group (P<0.01). Compared with the model group, the total amount of sAPPα was significantly increased in the Shenghui decoction group(P<0.01 and P<0.05), and only the sAPPα content at 12:00 was increased in the high dose group of Shenghui decoction (P<0.01), the sAPPα content at 24:00 was increased in the low dose group of Shenghui decoction (P<0.05). The sAPPα content had significant diurnal differences in the control group (P<0.01). However,it was disappeared in the model group (P>0.05). The sAPPα content had diurnal differences in the high dose group of Shenghui decoction(P<0.01). There was no diurnal difference in sAPPα content of the low dose group of Shenghui decoction (P>0.05). Western blotting results showed that the expression of Aβ_1-40 and Aβ_1-42 were significantly increased in the model group (P<0.01). Compared with the model group, the expression of Aβ_1-40 and Aβ_1-42 were reduced in the high dose group of Shenghui decoction (P<0.05, P<0.01); the expression of Aβ_1-40 was decreased in the low dose group of Shenghui decoction (P<0.05) and had no effect on the expression of Aβ_1-42 (P>0.05). Immunohistochemical results showed that the expression of Aβ_1-40 was significantly increased in the model group (P<0.01); the expression of Aβ_1-40 was reduced in different dose groups of Shenghui decoction (P<0.01, P<0.05).Conclusion Shenghui Decoction improves learning and memory impairment in 5-month-old APP / PS1 Alzheimer's disease model mice, which may be related to the restoration of circadian rhythm expression of APP metabolite sAPPα in hippocampus, thereby reducing the deposition of Aβ.

国家自然科学基金委员会青年科学基金项目(81703972)：基于生物钟基因对神经炎症的调控研究补肾安神益智法对阿尔茨海默病的干预作用；负责人：丁莉。