关键词: 家族性阿尔茨海默病, APPswe突变, MAPTp301s突变, 树鼩, 动物模型

Abstract: Objective　To construct AD tree shrew model by double transgenic injection of APPswe/ MAPTp30s in the hippocampus and to evaluate the pathological characteristics of AD. Methods　Experimental animals were randomly divided into a control group and an experimental group, with 6 animals in each group (half male and half female). AAV9-EGFP were injected into the left and right hippocampus of control group tree shrews with 2 μL per side (titer:1×1013 GC/mL) by brain stereotaxic technique.AAV9 vectors expressing APPswe genes were injected into the left hippocampus with 2 μL (titer: 1×1013 GC/mL) and AAV9 vectors expressing MAPTp301s genes were injected into the right hippocampus with 2 μL (titer: 1×1013 GC/mL) of experimental group tree shrews (APPswe/ MAPTp301s) by brain stereotaxic technique. The AD model pathological features were detected using immunofluorescence, immunohistochemistry, HE staining, Bieloschsky silver staining, Tunel staining, and Nissl staining. Serum SOD, MDA, and AchE activities were measured, and relevant protein expression was measured by Western blot. Results　Immunofluorescence confirmed the APPswe/ MAPTp301s was expressed in the experimental group tree shrews (APPswe/MAPTp301s) hippocampus. Compared to the control group (AAV9-EGFP), the experimental group (APPswe/MAPTp301s) showed significant Aβ plaque deposition, reduced neuron count, partial neuronal degeneration and necrosis, disappearance of Nissl body in the hippocampus (P<0.05) and cerebral cortex, activation of glial cells, significant neurofibrillary tangle formation (P<0.01), a significant decrease in serum SOD activity (P< 0.01), a significant increase in AchE enzyme activity (P<0.01), and significantly elevated expression levels of phosphorylated Tau protein (P-Tau181 and P-Tau217) in the olfactory bulb(P<0.01,P< 0.05).Conclusion　The APPswe/MAPTp301s double transgenic AD tree shrew model was successfully constructed, which provided a potential animal model for the pathological mechanism study, drug development and treatment of AD.

Key words: familial Alzheimer’s disease, APP Swedish mutation, MAPTp301s mutation, tree shrew, animal model