Fig 1.
Effects of age and running exercise (Ex) on the number of newly proliferated cells and that of immature neurons in the adult hippocampus.
Representative micrographs of BrdU+ newborn cells (A), DCX+ immature neurons (D) and BrdU+DCX+ newborn neurons (G) in the hippocampal dentate gyrus of mice at 3, 9 and 21 months of age. Sed: sedentary group. Bar = 100 μm. Enlarged micrographs of BrdU+ cells (B), DCX+ immature neurons (E) and BrdU+DCX+ newborn neurons (H) are presented to illustrate the detail locations of these cells. Bar = 20 μm. SGZ: subgranular zone; GCL: granular cell layer; MoL: molecular layer. Quantitative analyses of BrdU+ cells (C), DCX+ cells (F) and BrdU+DCX+ cells (I) in dentate gyrus of mice with different ages. ***: Bonferroni post-hoc test: p < 0.001 vs. respective Sed group.
Fig 2.
Effects of age and running exercise (Ex) on the number of neural stem/precursor cells (NSCs) in the adult hippocampus.
A) Representative micrographs of nestin+ cells in the hippocampal dentate gyrus of mice at 3, 9 and 21 months of age. Sed: sedentary group. Scale bar: 100 μm. B) Quantitative analyses of nestin+ cells in the dentate gyrus of mice with different ages.
Fig 3.
Effects of age and running exercise (Ex) on the proliferation rate, neuron lineage specification rate and survival rate of adult hippocampal neurogenesis.
A) Proliferation rate, estimated by dividing the number of BrdU+ cells by the number of nestin+ cells. B) Neuron lineage specification rate, estimated by dividing the number of BrdU+DCX+ cells by the number of BrdU+ cells. C) Survival rate, estimated by dividing the number of BrdU+ cells, 2 h after BrdU injection, by the number of BrdU+ cells 1 month after BrdU injection.
Fig 4.
Effects of age and running exercise (Ex) on the maturation of newborn neurons.
A) Representative micrographs of DCX+ immature neurons in the dentate gyrus of the 9 and 21-month-old mice that received or did not receive Ex training. Examples of tracings (blue line) are used to measure the quality of dendrite of DCX+ immature neurons. Sed: sedentary group. Scale bar: 20 μm. B) Quantitative results of the number of branches of DCX+ dendrite. C) Quantitative results of the total length of DCX+ dendrite. **: Bonferroni post-hoc test: p < 0.01 vs. respective Sed group.