Effects of voluntary running on plasma levels of neurotrophins, hippocampal cell proliferation and learning and memory in stressed rats

Suk Yu Yau, Wui Man Lau, E. D. Zhang, J. C.D. Lee, A. Li, T. M.C. Lee, Y. P. Ching, A. M. Xu, K. F. So

Research output: Journal article publicationJournal articleAcademic researchpeer-review

49 Citations (Scopus)

Abstract

Previous studies have shown that a 2-week treatment with 40. mg/kg corticosterone (CORT) in rats suppresses hippocampal neurogenesis and decreases hippocampal brain-derived neurotrophic factor (BDNF) levels and impairs spatial learning, all of which could be counteracted by voluntary wheel running. BDNF and insulin-like growth factor (IGF-1) have been suggested to mediate physical exercise-enhanced hippocampal neurogenesis and cognition. Here we examined whether such running-elicited benefits were accompanied by corresponding changes of peripheral BDNF and IGF-1 levels in a rat model of stress. We examined the effects of acute (5. days) and chronic (4. weeks) treatment with CORT and/or wheel running on (1) hippocampal cell proliferation, (2) spatial learning and memory and (3) plasma levels of BDNF and IGF-1. Acute CORT treatment improved spatial learning without altered cell proliferation compared to vehicle treatment. Acute CORT-treated non-runners showed an increased trend in plasma BDNF levels together with a significant increase in hippocampal BDNF levels. Acute running showed no effect on cognition, cell proliferation and peripheral BDNF and IGF-1 levels. Conversely, chronic CORT treatment in non-runners significantly impaired spatial learning and suppressed cell proliferation in association with a decreased trend in plasma BDNF level and a significant increase in hippocampal BDNF levels. Running counteracted cognitive deficit and restored hippocampal cell proliferation following chronic CORT treatment; but without corresponding changes in plasma BDNF and IGF-1 levels. The results suggest that the beneficial effects of acute stress on cognitive improvement may be mediated by BDNF-enhanced synaptic plasticity that is hippocampal cell proliferation-independent, whereas chronic stress may impair cognition by decreasing hippocampal cell proliferation and BDNF levels. Furthermore, the results indicate a trend in changes of plasma BDNF levels associated with a significant alteration in hippocampal levels, suggesting that treatment with running/CORT for 4 weeks may induce a change in central levels of hippocampal BDNF level, which may not lead to a significant change in peripheral levels.
Original languageEnglish
Pages (from-to)289-301
Number of pages13
JournalNeuroscience
Volume222
DOIs
Publication statusPublished - 11 Oct 2012
Externally publishedYes

Keywords

  • BDNF
  • Corticosterone
  • Hippocampal cell proliferation
  • IGF-1
  • Stress
  • Voluntary running

ASJC Scopus subject areas

  • Neuroscience(all)

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