PMID- 17497667
OWN - NLM
STAT- MEDLINE
DCOM- 20070725
LR  - 20220316
IS  - 0894-1491 (Print)
IS  - 1098-1136 (Electronic)
IS  - 0894-1491 (Linking)
VI  - 55
IP  - 9
DP  - 2007 Jul
TI  - Exercise decreases myelin-associated glycoprotein expression in the spinal cord 
      and positively modulates neuronal growth.
PG  - 966-75
AB  - To successfully grow, neurons need to overcome the effects of hostile 
      environments, such as the inhibitory action of myelin. We have evaluated the 
      potential of exercise to overcome the intrinsic limitation of the central nervous 
      system for axonal growth. In line with the demonstrated ability of exercise to 
      increase the regenerative potential of neurons, here we show that exercise 
      reduces the inhibitory capacity of myelin. Cortical neurons grown on myelin from 
      exercised rats showed a more pronounced neurite extension compared with neurons 
      grown on poly-D-lysine, or on myelin extracted from sedentary animals. The 
      activity of cyclin-dependent kinase 5, a kinase involved in neurite outgrowth, 
      was found to be increased in cortical neurons grown on exercise-myelin and in the 
      lumbar spinal cord enlargement of exercised animals. Exercise significantly 
      decreased the levels of myelin-associated glycoprotein (MAG), a potent axonal 
      growth inhibitor, suggesting that downregulation of MAG is part of the mechanism 
      through which exercise reduces growth inhibition. It is known that exercise 
      elevates brain-derived neurotrophic factor (BDNF) spinal cord levels and that 
      BDNF acts to overcome the inhibitory effects of myelin. Accordingly, we blocked 
      the action of BDNF during exercise, which suppressed the exercise-related MAG 
      decrease. Protein kinase A (PKA) has been related to the ability of BDNF to 
      overcome growth inhibition; in agreement, we found that exercise increased PKA 
      levels and this effect was reverted by blocking BDNF. Overall, these results show 
      that exercise promotes a permissive cellular environment for axonal growth in the 
      adult spinal cord requiring BDNF action.
CI  - (c) 2007 Wiley-Liss, Inc.
FAU - Ghiani, Cristina A
AU  - Ghiani CA
AD  - Jane and Terry Semel Institute for Neuroscience and Human Behavior, Department of 
      Neurobiology and Psychiatry, David Geffen School of Medicine, University of 
      California at Los Angeles, Los Angeles, CA 90095, USA.
FAU - Ying, Zhe
AU  - Ying Z
FAU - de Vellis, Jean
AU  - de Vellis J
FAU - Gomez-Pinilla, Fernando
AU  - Gomez-Pinilla F
LA  - eng
GR  - R01 NS045804/NS/NINDS NIH HHS/United States
GR  - NS45804/NS/NINDS NIH HHS/United States
GR  - HD04612/HD/NICHD NIH HHS/United States
GR  - HD06576/HD/NICHD NIH HHS/United States
GR  - P01 HD006576/HD/NICHD NIH HHS/United States
GR  - R01 NS050465/NS/NINDS NIH HHS/United States
GR  - P30 HD004612/HD/NICHD NIH HHS/United States
GR  - R01 NS050465-02/NS/NINDS NIH HHS/United States
GR  - NS050465/NS/NINDS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PL  - United States
TA  - Glia
JT  - Glia
JID - 8806785
RN  - 0 (Brain-Derived Neurotrophic Factor)
RN  - 0 (Growth Inhibitors)
RN  - 0 (Myelin-Associated Glycoprotein)
RN  - EC 2.7.11.1 (Cyclin-Dependent Kinase 5)
RN  - EC 2.7.11.11 (Cyclic AMP-Dependent Protein Kinases)
RN  - EC 2.7.11.22 (Cdk5 protein, rat)
SB  - IM
MH  - Animals
MH  - Brain-Derived Neurotrophic Factor/antagonists & inhibitors/metabolism
MH  - Cell Differentiation/physiology
MH  - Cells, Cultured
MH  - Cerebral Cortex/cytology/drug effects/metabolism
MH  - Cyclic AMP-Dependent Protein Kinases/metabolism
MH  - Cyclin-Dependent Kinase 5/metabolism
MH  - Down-Regulation/physiology
MH  - Growth Cones/drug effects/*metabolism
MH  - Growth Inhibitors/metabolism
MH  - Male
MH  - Myelin Sheath/*metabolism
MH  - Myelin-Associated Glycoprotein/*metabolism
MH  - Nerve Regeneration/drug effects/physiology
MH  - Neuronal Plasticity/drug effects/physiology
MH  - Physical Conditioning, Animal/*physiology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Spinal Cord/cytology/*metabolism
MH  - Up-Regulation/physiology
PMC - PMC2805662
MID - NIHMS161109
EDAT- 2007/05/15 09:00
MHDA- 2007/07/26 09:00
PMCR- 2010/01/12
CRDT- 2007/05/15 09:00
PHST- 2007/05/15 09:00 [pubmed]
PHST- 2007/07/26 09:00 [medline]
PHST- 2007/05/15 09:00 [entrez]
PHST- 2010/01/12 00:00 [pmc-release]
AID - 10.1002/glia.20521 [doi]
PST - ppublish
SO  - Glia. 2007 Jul;55(9):966-75. doi: 10.1002/glia.20521.