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IPFS News Link • Science, Medicine and Technology

Natural enzyme re-engineered to tackle stroke and spinal cord damage

• https://newatlas.com, By Nick Lavars

This forms what is known as a glial scar, which protects against further injury but can impede long-term nerve repair. Scientists have now redesigned an enzyme found in nature that selectively untangles some of the scarring in a way that promotes regrowth of the nerve cells, opening up new pathways in the development of treatments for these types of conditions.

The breakthrough comes from a team of engineers from the University of Toronto and the University of Michigan, but can be traced back a couple of decades to when scientists discovered an interesting function of an enzyme called chondroitinase ABC, which is produced in nature by bacteria. A glial scar consists of tightly woven cells and biochemicals that come together around the damaged nerve, and it was found that chondroitinase ABC could selectively degrade some of these building blocks in useful ways.

So much so that follow-up studies demonstrated how the enzyme could promote regrowth of nerve cells, with some experiments even demonstrating how it could lead injured animals to recover some of their lost functions. But scientists kept running into the same roadblock, with the enzyme proving too unstable for the job at hand.

"It's stable enough for the environment that the bacteria live in, but inside the body it is very fragile," says Shoichet. "It aggregates, or clumps together, which causes it to lose activity. This happens faster at body temperature than at room temperature. It is also difficult to deliver chondroitinase ABC because it is susceptible to chemical degradation and shear forces typically used in formulations."