Figure 4 shows that the number of BrdU-positive cells was significantly higher at 24 h than at 28 days, indicating that many new cells died. This result was consistent with those of the apoptosis assay shown in the Appendix A Figure A1. Although APP/PS1 transgenic mice had many more new cells than the wild-type ones at 24 h (Figure 4C), after 28 days, AD mice had fewer new cells, resulting in a much lower survival ratio (Figure 4D). However, treadmill exercise significantly increased new cell survival in both AD and WT mice (p < 0.01). The gene discussed is APP; the disease is Alzheimer disease.