Chondroitinase treatment explained

Chondroitinase treatment
Specialty:neurology

Chondroitinase treatment is a treatment of proteoglycans, a protein in the fluid among cells where (among other things) they affect neural activity (communication, plasticity).[1] Chondroitinase treatment has been shown to allow adults vision to be restored as far as ocular dominance is concerned.[2] Moreover, there is some evidence that Chondroitinase could be used for the treatment of spinal injuries.[3]

In addition, the enzyme that is used in the chondroitinase treatment, chondroitinase ABC, derives from the bacterium Proteus vulgaris.[4] In recent years, pre-clinical research involving the chondroitinase ABC enzyme has been mainly directed towards utilizing it as a way of treating spinal cord injuries in test animals using viral vectors.[5] In general, the way chondroitinase ABC works in vivo is it cleaves off the side chains of molecules known as chondroitin sulfate proteoglycans (CSPGs) which are over produced by glial cells in the central nervous system when a spinal injury occurs. When chondroitin sulfate proteoglycans are bonded to their side chains called chondroitin sulfate glycosaminoglycans, these molecules are known to prevent neural restoration to the damaged region of the central nervous system because they form glial scar tissue which inhibits both neuroplasticity and repair of damaged axons.[6] However, when the side chains of the chondroitin sulfate proteoglycans are cleaved by chondroitinase ABC, this promotes the damaged region of the CNS to recover from the spinal cord injury.

It has recently been proposed that chondroitinase treatment promotes plasticity by activation of Tropomyosin receptor kinase B, receptor for Brain-derived neurotrophic factor and a major plasticity orchestrator in the brain.[7] Cleavage of CSPGs by chondroitinase ABC leads to inactivation of PTPRS, the membrane receptor for CSPGs and a phosphatase that inactivates TRKB under normal physiological conditions, which subsequently promotes TRKB phosphorylation and activation of neuroplasticity.

See also

Notes and References

  1. Cambridge Centre for Brain Repair, School of Clinical Medicine, Cambridge Centre for Brain Repair. Plasticity and the extracellular matrix.
  2. Book: Hensch TK . Critical period mechanisms in developing visual cortex . 69 . 215–37 . 2005 . 16243601 . 10.1016/S0070-2153(05)69008-4 . 9780121531690 . Current Topics in Developmental Biology . Neural Development .
  3. News: Spinal injury regeneration hope. . BBC NEWS, online . 17 February 2008 . 2009-12-31 .
  4. Zhao RR, Fawcett JW . Combination treatment with chondroitinase ABC in spinal cord injury--breaking the barrier . Neuroscience Bulletin . 29 . 4 . 477–83 . August 2013 . 23839053 . 5561941 . 10.1007/s12264-013-1359-2 .
  5. Burnside ER, De Winter F, Didangelos A, James ND, Andreica EC, Layard-Horsfall H, Muir EM, Verhaagen J, Bradbury EJ . Immune-evasive gene switch enables regulated delivery of chondroitinase after spinal cord injury . Brain . 141 . 8 . 2362–2381 . August 2018 . 29912283 . 6061881 . 10.1093/brain/awy158 .
  6. Bradbury EJ, Carter LM . Manipulating the glial scar: chondroitinase ABC as a therapy for spinal cord injury . Brain Research Bulletin . 84 . 4–5 . 306–16 . March 2011 . 20620201 . 10.1016/j.brainresbull.2010.06.015 . 10605553 .
  7. Lesnikova. Angelina. Casarotto. Plinio Cabrera. Fred. Senem Merve. Voipio. Mikko. Winkel. Frederike. Steinzeig. Anna. Antila. Hanna. Umemori. Juzoh. Biojone. Caroline. Castrén. Eero. 2020-12-08. Chondroitinase and antidepressants promote plasticity by releasing TRKB from dephosphorylating control of PTPσ in parvalbumin neurons. Journal of Neuroscience. 41 . 5 . 972–980 . en. 10.1523/JNEUROSCI.2228-20.2020. 7880295. 0270-6474. 33293360. free.