Chondroitin Sulfate Proteoglycan May Have Many Roles In Spinal Cord Injury Repair

The proteoglycan chondroitin sulfate (CSPG) plays an important role not
just in the formation of the glial scar but also in the repair of
spinal cord injury, according to an article released on August 18, 2008
in the open-access journal PLoS Medicine.



In injuries to the central nervous system such as spinal cord injury,
the glial scar is formed in a similar manner to scars in other parts of
the body. However, while protecting the damaged area in many ways, it
simultaneously releases chemicals that inhibit further regeneration.
Within the glial scar, several major types of cells appear, in
particular microglia and macrophages. The proteoglycan molecule
chondroitin sulfate plays a vital role in the inhibition of neuronal
regeneration, but according to the article, the increased synthesis of
this compound indicates it might actually play a dual rold in this
process.



Michal Schwartz, of the Weizmann Institute of Science, and colleagues
performed several experiments in mice to explore this dual role in the
acute phase of healing after a spinal cord injury. Evaluating spinal
cord damage through the proteins and cells that are present, the
researchers postulate that the proteoglycan in fact has an important
role in the healing process by controlling intervening cells in
communication pathways.



They conclude that the present goal to reduce expression of chondroitin
sulfate may not be productive, and that it may be more important to
modulate it in therapies for such injuries. They say that "timing and
the extent of degradation should be carefully selected according to the
changing requirements of the ongoing dynamic repair process."



They conclude with a call for further research in the formation and
maintenance of the glial scar: "Moreover, since CSPG is a major
constituent of the glial scar, the present findings raises the
potential need to revisit the overall perception of the glial scar and
its role in recovery. A better understanding of the regulation of the
scar tissue and the role of the naturally occurring CSPG in health and
disease will enable us to increase the benefit of endogenous repair
mechanisms and improve many of the available therapies for CNS injury."




Two faces of chondroitin sulfate proteoglycan in spinal cord
repair: A role in microglia/macrophage activation.

Rolls A, Shechter R, London A, Segev Y, Jacob-Hirsch J, et al.

PLoS Med 5(8): e171.

doi:10.1371/journal.pmed.0050171

Click
Here For Full Length Article



Written by Anna Sophia McKenney