Induction of Striatal Neurogenesis by Voluntary Exercise and Environmental Enrichment

ABSTRACT

OBJECTIVE: To investigate that neurogenesis in the subventricular zone (SVZ), which is already known as neurogenic area where neural stem/progenitor cells persist, and the striatum, which is non-neurogenic area, might be induced by voluntary exercise (VEx) or environmental enrichment (EE), and compare the extent of the neurogenesis with untreated controls. METHOD: Total 12 C57BL/6 mice, 2~3 months old, were recruited as follows; voluntary wheel runner, EE and control. For 2 weeks, VEx group was housed in rat cage (48x26 cm) with 2 running wheels with 3~4 animals/cage, and EE group was housed in the living condition of huge cage (86x76 cm), social interaction (13~14 mice/cage) and objects such as toys, tunnels and running wheel, whereas control group was placed in the standard cage (30x18 cm). RESULTS: VEx and EE tended to increase the densities of mitotic marker BrdU+ cells in SVZ and striatum. They also exhibited more BrdU+ cells (/mm3) into the striatum, even though they did not show statistical significance. Moreover, EE group showed significant increment of the newly generated neurons coexpressed with BrdU+ and betaIII-tubulin+ (/mm3) in SVZ and striatum as compared to those of controls. CONCLUSION: Voluntary physical exercise and EE induced cell proliferation and neurogenesis in both SVZ and striatum. Characteristically, EE could significantly induce neurogenesis in striatum, non-neurogenic area as well as SVZ, typical neurogenic area. Therefore, this strategy might be used to activate neural regeneration in various central nervous system diseases.