Department of Integrated Biosciences, University of Tokyo, Bioscience Building 402, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
Neurobiol Aging. 2011 Jan;32(1):140-50. doi: 10.1016/j.neurobiolaging.2008.12.011. Epub 2009 Feb 6.
In the dentate gyrus of the hippocampus, new neurons are generated from neural stem/progenitor cells (NPCs) throughout life. As aging progresses, the rate of neurogenesis decreases exponentially, which might be responsible, in part, for age-dependent cognitive decline in animals and humans. However, few studies have analyzed the alterations in NPCs during aging, especially in primates. Here, we labeled NPCs by triple immunostaining for FABP7, Sox2, and GFAP and found that their numbers decreased in aged macaque monkeys (>20 years old), but not in aged mice. Importantly, we observed marked morphological alterations of the NPCs in only the aged monkeys. In the aged monkey hippocampus, the processes of the NPCs were short and ran horizontally rather than vertically. Despite these alterations, the proliferation rate of the NPCs in aged monkeys was similar to that in young monkeys. Thus, morphological alterations do not affect the proliferation rate of NPCs, but may be involved in the maintenance of NPCs in aged primates, including elderly humans.
在海马齿状回中，新的神经元由神经干细胞/祖细胞（NPCs）生成，并且这种生成过程贯穿人的一生。随着年龄的增长，神经发生的速度呈指数级下降，这可能部分导致了动物和人类的年龄相关认知能力下降。然而，很少有研究分析 NPCs 在衰老过程中的变化，特别是在灵长类动物中。在这里，我们通过对 FABP7、Sox2 和 GFAP 进行三重免疫染色来标记 NPCs，发现它们的数量在老年猕猴（>20 岁）中减少，但在老年小鼠中没有减少。重要的是，我们仅在老年猕猴中观察到 NPCs 的明显形态改变。在老年猕猴的海马中，NPCs 的突起短小且呈水平方向而非垂直方向延伸。尽管存在这些变化，但老年猕猴 NPCs 的增殖率与年轻猕猴相似。因此，形态改变不会影响 NPCs 的增殖率，但可能参与了包括老年人类在内的老年灵长类动物中 NPCs 的维持。
