有氧训练对阿尔茨海默病模型大鼠海马齿状回神经发生的影响

Effects of Aerobic Training on Neurogenesis in the Denatate Gyrus of Hippocampus in Alzheimer’s Disease Model Rats

目的:观察有氧训练对β淀粉样蛋白25-35(Aβ25-35)诱导的阿尔茨海默病(AD)大鼠齿状回(DG)神经发生的影响。方法:SD大鼠48只,随机分为假手术组(侧脑室注射生理盐水),有氧训练组(侧脑室注射Aβ25-35+4周有氧训练)和实验组(侧脑室注射Aβ25-35)。3组大鼠行Morris水迷宫行为学检测,免疫组织化学方法检测海马DGBrdU阳性细胞数,以确定有氧训练对细胞存活的影响;微管相关蛋白免疫组化染色观察新生神经元的突起生长。结果:①与假手术组比,实验组逃避潜伏期显著延长(P<0.05);有氧训练组与实验组比,逃避潜伏期明显缩短(P<0.05);有氧训练组逃避潜伏期与假手术组比,差异无统计学意义。②与假手术组比,实验组DGBrdU阳性细胞数显著减少(P<0.05)。③与假手术组比,实验组DG新生神经元突起的数量明显减少(P<0.05)。④与实验组比,有氧训练可改善DGBrdU阳性细胞的显著减少(P<0.05)、保护神经元突起的生长(P<0.05)。结论:Aβ25-35能诱导AD大鼠模型的建立,损害新生神经元突起生长和新生神经元的存活;有氧训练可改善Aβ25-35损害的大鼠新生神经元突起生长和新生神经元的存活。

Aim： To observe the effects of aerobic trainings on neurogenesis in the denatate gyrus in Alzheimer’s disease rats. Methods： There were 48 SD rats divided into three groups randomly： sham operation group（injected saline from lateral ventricles） , aerobic trainings group（injected Ab25-35 from lateral ventricles with aerobic training for four weeks ）, AD group （injected Ab25-35 from lateral ventricles only）. Then they were tested in Morris water maze, BrdU and microtubule-associated proteins immuno-reactivities were visualized by avidin-biotin horseradish peroxidase complex through immunohistochemistry. BrdU was used to determine the survival of newborn in the hippocampal dentate gyrus （DG）, and DCX was used to investigate the neurite growth of newborn neurons. Results： ①In Morris water maze test, the time for escape latency in the sham operation group and aerobic training group were shorter than the experimental group（P0.05）. There was no statistical difference between the sham operation group and the aerobic training group（P0.05）.②Compared with the sham operation group, AD group impaired survival of newborn neurons in the DG（P0.05）. ③Compared with the sham operation group, AD group impaired neurite growth of newborn neurons（P0.05）. ④Compared with the experimental group, aerobic training prevented Ab25-35-impaired survival of newborn neurons（P0.05） and protected the neurite growth of newborn neurons（P0.05）. Conclusion： Ab25-35 can induce neurodegeneration in AD model, and impair neurite growth of newborn neurons and survival of newborn neurons in the DG. Aerobic training can prevent Ab25-35-impaired survival of newborn neurons and protect the neurite growth of newborn neurons.