J Korean Neurosurg Soc.  2013 Jun;53(6):337-341. 10.3340/jkns.2013.53.6.337.

Epigenetic Regulation in the Brain after Spinal Cord Injury : A Comparative Study

• Park BN
• Kim SW
• Cho SR
• Lee JY
• Lee YH
• Kim SH

• KMID: 2190820
• DOI: http://doi.org/10.3340/jkns.2013.53.6.337

Abstract

OBJECTIVE
After spinal cord injury (SCI), functional and structural reorganization occurs at multiple levels of brain including motor cortex. However, the underlying mechanism still remains unclear. The current study was performed to investigate the alterations in the expression of the main regulators of neuronal development, survival and death, in the brain following thoracic contusive SCI in a mouse model.
METHODS
Eight-week-old female imprinting control region mice (n=60; 30-35 g) were used in this study. We analyzed the expression levels of regulators such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and histone deacetylase (HDAC) 1 in the brain following thoracic contusive SCI.
RESULTS
The expression of BDNF levels were elevated significantly compared with control group at 2 weeks after injury (p<0.05). The expression of NGF levels were elevated at 2, 4 weeks compared with control group, but these difference were not significant (p>0.05). The GDNF levels were elevated at 2 week compared with control group, but these differences were not significant (p>0.05). The difference of HDAC1 levels were not significant at 2, 4 and 8 weeks compared with control group (p>0.05).
CONCLUSION
These results demonstrate that the upregulation of BDNF may play on important role in brain reorganization after SCI.

Keyword

Spinal cord injury; Regulators; Brain; Brain derived neurotrophic factor; Epigenetic

MeSH Terms

Animals
Brain
Brain-Derived Neurotrophic Factor
Epigenomics
Female
Glial Cell Line-Derived Neurotrophic Factor
Histone Deacetylases
Humans
Mice
Motor Cortex
Nerve Growth Factor
Neurons
Spinal Cord
Spinal Cord Injuries
Up-Regulation
Brain-Derived Neurotrophic Factor
Glial Cell Line-Derived Neurotrophic Factor
Histone Deacetylases
Nerve Growth Factor

Figure

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  Fig. 1 Schematic drawing illustrating operation of spinal cord injury using Infinite Horizons Impactor.

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  Fig. 2 Semi-quantitative immunoblot analysis of BDNF expression in brain after contusion of the spinal cord in mice (A and B). BDNF significantly elevated compared with those of control group at 2 week after SCI (p<0.05). In this figure (B) data are plotted as mean±standard error of the mean. A sterisk indicate values significantly different from those of SCI and of control group by using a two-way repeated measures analysis of variance with repeated time factor. BDNF : brain-derived neurotrophic factor, SCI : spinal cord injury, CONT : control, GAPDH : glyceraldehyde 3-phosphate dehydrogenase.

• 

  Fig. 3 Semi-quantitative immunoblot analysis of NGF expression in brain after contusion of the spinal cord in mice (A and B). NGF elevated compared with those of control group at 2 and 4 weeks, however the differences were not significant (p>0.05). In this figure (B) data are plotted as mean±standard error of the mean. NGF : nerve growth factor, SCI : spinal cord injury, CONT : control, GAPDH : glyceraldehyde 3-phosphate dehydrogenase.

• 

  Fig. 4 Semi-quantitative immunoblot analysis of GDNF expression in brain after contusion of the spinal cord in mice (A and B). GDNF elevated compared with those of control group at 2 weeks, however the difference is not significant (p>0.05). In this figure (B) data are plotted as mean±standard error of the mean. GDNF : glial cell line-derived neurotrophic factor, SCI : spinal cord injury, CONT : control, GAPDH : glyceraldehyde 3-phosphate dehydrogenase.

• 

  Fig. 5 Semi-quantitative immunoblot analysis of HDAC1 expression in brain after contusion of the spinal cord in mice (A and B). The difference of HDAC1 level in SCI and control group is not significant (p>0.05). In this figure (B) data are plotted as mean±standard error of the mean. HDAC : histone deacetylase, SCI : spinal cord injury, CONT : control, GAPDH : glyceraldehyde 3-phosphate dehydrogenase.

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