APP5肽类似物P165对糖尿病小鼠海马突触蛋白的影响

目的探讨β-淀粉样前体蛋白（APP）5肽类似物P165对糖尿病小鼠海马神经元α-突触核蛋白（α-Syn）、Shank1和突触后致密物质95（PSD-95）的影响。方法链脲佐菌素腹腔注射诱发DM小鼠模型，P165灌胃治疗。5周后，行灌注固定，海马CA1区α-Syn、Shank1和PSD-95免疫组织化学染色。结果与对照组相比，糖尿病（DM）组α-Syn阳性细胞增多（P〈0.01），胞浆突起深染，Shank1和PSD-95阳性细胞减少，染色浅（P〈0.01）；与DM组相比，P165治疗组α-Syn阳性细胞减少（P〈0.05），胞浆突起染色变浅；Shank1和PSD-95阳性细胞增多（P〈0.05），胞浆突起深染。结论糖尿病小鼠海马神经元存在突触蛋白表达的异常，P165可改善DM小鼠海马神经元突触蛋白的表达。

Effects of P165 on the modulating of synaptic proteins in the hippocampus of STZ-DM mice

Objective To investigate the effects of P165 on regulating the expression of α-synapse nucleoprotein（SNP）, Shank1 and PSD-95 （postsynaptic density-95）in hippocampal neurons of DM mice. Methods The models of DM mice were made by STZ. In treated group, P165 was injected into the stomach everyday, Whereas in control group and DM group, the mice were given the saline of the same volume. After five weeks,α-SNP,Shank1 and PSD-95 were detected by immunohistochemistry. Results In DM vs control groups, positive neurons of α-SNP increased（P〈0.01）, and were stained deeper. while the positive neurons of Shank1 and PSD-95 groups decreased （P〈0.01） and were stained lighter. Compared with DM group,in treated group, positive neurons of α-SNP dereased （P〈0.05）and were stained lighter, while the positive neurons of Shank1 and PSD-95 groups increased（P〈0.05）and were stained deeper. Conclusion Abnormal expressions of these proteins may contribute to the mechanisms of diabetic encephalopathy, and P165 may improve this situation.