Achucarro Basque Center for Neuroscience, Leioa, Bizkaia, Spain.
University of the Basque Country UPV/EHU, Leioa, Bizkaia, Spain.
Sci Rep. 2017 Nov 28;7(1):16528. doi: 10.1038/s41598-017-16466-3.
Adult hippocampal neuroprogenitors give rise to both neurons and astrocytes. As neuroprogenitors are lost with increased age, neurogenesis concomitantly decreases. However, the dynamics of neuron and astrocyte generation throughout adulthood has not been systematically examined. Here, we analyzed the hippocampal niche both longitudinally (from 2 h to 30d of cell life) and transversally (from 1 m to 12 m of age) and generated a Marsaglia polar random simulation model to predict newborn cell dynamics. The sharp decrease in newborn neuron production throughout adulthood was largely predicted by the number of proliferating neuroprogenitors at each age. In contrast, newborn astrocyte decay was slower and associated with their increased yield in mature mice. As a result, the niche shifted from neurogenic to neuro/astrogenic with increased age. Our data provide a simple "end-point" model to understand the hippocampal niche changes across adulthood and suggest yet unexplored functions of newborn astrocytes for the aging hippocampal circuitry.
成年海马神经前体细胞既能产生神经元也能产生星形胶质细胞。随着年龄的增长，神经前体细胞逐渐减少，神经发生也随之减少。然而，成年期神经元和星形胶质细胞生成的动态变化尚未得到系统研究。在这里，我们分析了海马生态位的纵向（从细胞存活的 2 小时到 30 天）和横向（从 1 个月到 12 个月的年龄）变化，并生成了一个 Marsaglia 极地随机模拟模型来预测新生细胞的动态。整个成年期新生神经元生成的急剧减少在很大程度上可以由每个年龄的增殖神经前体细胞数量来预测。相比之下，新生星形胶质细胞的衰减较慢，这与成熟小鼠中它们产量的增加有关。因此，随着年龄的增长，生态位从神经发生向神经/星形胶质发生转变。我们的数据提供了一个简单的“终点”模型来理解成年期海马生态位的变化，并暗示了新生星形胶质细胞在衰老海马回路中尚未被探索的功能。
