"The strategy was to use a simple, one-time injection of an enzyme, chondroitinase
, that breaks down the inhibitory proteoglycan molecules," says senior author Jerry Silver, PhD, professor of neurosciences at Case Western Reserve University School of Medicine.
The gene therapy causes cells to produce an enzyme called chondroitinase
which can break down the scar tissue and allow networks of nerve cells to regenerate.
When PNNs are enzymatically degraded with chondroitinase
ABC in the PFC, GABAergic cell firing decreases  and pyramidal cell firing increases , providing evidence that PNNs play a key role in maintaining local inhibition.
Besides hyaluronidase, other high-molecular-weight enzymes, namely, heparinase and chondroitinase
, are reported to decrease ESL thickness and charge density with subsequent increment in albumin clearance .
Other experimental protocols were performed with the perfused liver model to test the role of 2 mmol/L calcium added to the perfusion buffered solution, as well as the addition of modifiers of the endothelium glycocalyx, such as hyaluronidase type IV (EC 184.108.40.206), heparanase III (E.C.220.127.116.11), and chondroitinase
(EC 18.104.22.168) from Proteus vulgaris, which were dissolved in the perfusion buffered solution to a final concentration of 15 mU/mL; moreover, heat inactivation of these enzymes was performed by immersing the hyaluronidase or heparanase stock solution in boiling water for 30 min.
Glial scar, an extrinsic environment for axon regeneration, acts like physical and chemical barriers and is mainly composed of reactive astrocytes, with the upregulation of glial fibrillary acidic protein (GFAP) and vimentin, the hallmarks of the gliosis process, and extracellular matrix molecules particularly interact with the chondroitin sulfate proteoglycans (CSPGs), which is degenerated by Chondroitinase
ABC (ChABC) allowing axon regeneration and function recovery in SCI .
ABC (ChABC) decomposes chondroitin sulfate proteoglycans in the glial scar that forms following SCI, allowing stem cells to penetrate through the scar and promote recovery of nerve function.
Rather than measuring chondroitin content indirectly by observing how it reacted with another chemical, this method measured it directly by using an enzyme called chondroitinase
ACII to break it into smaller pieces that could then be individually measured using chromatography with UV detection.
Thus, dermatan sulfate was removed from isolated GAGs samples using depolymerisation with chondroitinase
B (from Flavobacterium heparinum); then, the mixture of heparinase I and heparinase III (both from Flavobacterium heparinum) was added to a reaction medium in order to remove heparin sulfate/heparin.
The majority of developmental work performed in pharmacologic vitreolysis and vitreodynamics involves enzymes including hyaluronidase, chondroitinase
, tissue plasminogen activator, dispase, urokinase and plasmin.
The extract is treated for 2 h with chondroitinase
B followed by addition of disaccharide internal standard, boiling, and centrifugation.
Building on a technique developed by her colleagues at Case Western Reserve University in Cleveland, Warren injected an enzyme called chondroitinase
ABC into the rats' spinal cords to clear out scar tissue a year and a half after the injury.