The exercise-induced enhancement of learning and
memory, and its ability to slow age-related cognitive
decline in humans led us to investigate whether
running stimulates periventricular (PVR) neural stem
cells (NSCs) in aging mice, thereby augmenting the
regenerative capacity of the brain. To establish a
benchmark of normal aging on endogenous NSCs, we
harvested the PVR from serial vibratome sections
through the lateral ventricles of juvenile (6-8 weeks), 6,
12, 18, and 24-month-old mice, culturing the cells in the
neural colony forming cell assay. A significant decline
in NSC frequency was apparent by 6-months (~40%)
ultimately resulting in a ~90% reduction by 24-months.
Concurrent with this decline was a progressive loss in
regenerative capacity, as reflected by an incomplete
repopulation of neurosphere-forming cells following
gamma cell irradiation-induced depletion of the PVR.
However voluntary exercise (i.e. 21 days of running)
significantly increased NSC frequency in mic
