目的：阿尔茨海默症(Alzheimer’s disease, AD)是一种神经退行性疾病，患者出现认知障碍，记忆丧失等症状，该病严重危害中老年人身体健康。蜂王浆(Royal jelly, RJ)中发挥抗衰老、提高机体免疫力、促进生长发育功能的主要物质是蛋白成分。实验室前期通过分离纯化蜂王浆蛋白，结合细胞学相关实验进行验证，成功鉴定出王浆蛋白中具有药效活性的多肽序列，通过人工合成的方式简化了天然多肽纯化提取过程，提高了其产量、纯度和稳定性。本文通过探究蜂王浆多肽 (royal jelly peptides,RJP) 对APP/PS1双转基因小鼠模型(一种AD小鼠模型)认知能力、病理状态的影响，研究其药效及作用机制，以期为后期评价蜂王浆多肽对AD患者的治疗有效性及新药研发提供理论支撑。

方法：将3月龄的雄性小鼠随机分成5组，包括模型组（APP/PS1转基因型小鼠）、对照组（野生型小鼠）、3组高中低剂量的多肽给药组（APP/PS1转基因型小鼠），每组各10只，单只每笼喂养于SPF级动物房内，并每12小时进行一次的暗明交替光线的照射，每只小鼠均可自由饮食。通过灌胃的方式给药四个月，在行为学水平上，使用Morris水迷宫检测各组小鼠记忆认知功能；使用免疫荧光双染实验方法检测各组Aβ和小胶质细胞标志物Iba1含量的变化；通过免疫组化技术检测脑组织突触标志物突触素、自噬小体标志物LC3B在各组小鼠中的表达差异；通过Tunel试剂盒方法，分析各组小鼠脑组织细胞凋亡的情况；利用AKT通路蛋白芯片，检测p-akt及其下游p-mTOR，p-GSK3α，p-GSK3β，p-BAD， p-p27和p-p53等蛋白的磷酸化水平，结合通路各组分功能，探究蜂王浆多肽改善APP/PS1小鼠认知能力和病理特征的作用机制。

结果与结论：水迷宫行为学实验结果显示，与对照组相比，模型组小鼠空间记忆能力和认知水平显著下降，而各给药组APP/PS1小鼠相对于模型组，记忆能力和认知功能显著提高，与野生型对照组更加接近，显示蜂王浆多肽可以改善小鼠认知功能。免疫荧光标记实验结果显示，给药组和对照组相较于模型组，Aβ、lba1积累程度明显降低，显示蜂王浆多肽能够抑制对Aβ的积累，减少小胶质细胞增殖。免疫组化实验表明，与模型组相比，给药组和对照组突触标志物SYN的表达水平上调，这证明蜂王浆多肽能够保护突触结构，从而保障神经元细胞突触间的信息传递；Tunel凋亡染色实验结果显示，模型组脑组织中凋亡细胞占总细胞比例远高于给药组和对照组，说明蜂王浆多肽能够显著的抑制APP/PS1小鼠脑神经元细胞的凋亡；与模型组相比，给药组小鼠脑组织中自噬小体标记物LC3B的含量降低，且和正常组表现一致，这说明蜂王浆多肽能够参与调控自噬，减少自噬小体的病理性积累；利用蛋白芯片对AKT信号通路相关蛋白进行检测，其结果显示，与模型组相比，在正常组和给药p-akt及其下游p-mTOR，p-GSK3α，p-GSK3β， p-p27和p-p53等参与到细胞凋亡、自噬、突触发育生长等过程的蛋白表达，表现出了显著的差异，这可能是蜂王浆多肽发挥作用的机制。得出结论，蜂王浆多肽对于改善AD小鼠认知能力和脑组织病变具有积极作用。

Results and conclusion: The results of Morris water maze behavioral experiment showed that compared with the model group, APP / PS1 mice in each dose group significantly improved their spatial memory ability and cognitive level, which was closer to the normal wild-type control group, indicating that the royal jelly polypeptide can improve the cognitive function of mice. The results of immunofluorescence labeling showed that the accumulation of Aβ and IBA1 in the treatment group and the control group was significantly lower than that in the model group, indicating that the royal jelly polypeptide can inhibit the deposition of Aβ. Compared with the model group, the expression level of SYN was up-regulated in the administration group and the normal group, which proved that the royal jelly polypeptide could protect the synaptic structure, thus ensuring the information transmission between the synapses of neurons; TUNEL apoptotic staining showed that the proportion of apoptotic cells in brain tissue of model group was much higher than that of administration group and control group, which indicated that royal jelly polypeptide could significantly inhibit the apoptosis of brain neurons in APP/PS1 mice; tcompared with the model group, the content of LC3B in the brain tissue of mice in the administration group was reduced, which was consistent with the normal group .It is suggested that the royal jelly polypeptide can participate in the regulation of autophagy and reduce the pathological accumulation of autophagy bodies; he result of Akt chips showed that compared with model group, the normal group and administration group had significant differences of p-akt, p-mTOR, p-GSK3α, p-GSK3β, p-p27 and p-p53 and other proteins which take part in apoptosis, autophagy, synaptic development and growth, it may explores the mechanism of action of royal jelly polypeptide . It is concluded that  royal jelly polypeptide has a positive effect on improving cognitive ability and brain pathological changes of AD mice.