A recent biotechnology breakthrough has resulted in scientists creating a drug that has been proven to get paralysed mice back on their feet. The hope, of course, is that this indicates that the new drug will eventually lead to the rehabilitation of humans with severe injuries to their spinal cord by reactivating dormant circuits.
Due to the complex and fragile nerve systems that send signals to the brain, spinal cord injuries are among the most difficult of all for doctors and surgeons to treat. However, unless the spinal cord is completely severed, even in the case of severe injuries, at least some undamaged nerves remain. For reasons which are not completely clear the theoretically healthy remaining nerves often do not start re-sending signals once having lapsed into dormancy following an injury. Until now the only way that has succeeded in getting the firing again, and with limited success, has been through intensive electrical stimulation.
The recent research that has demonstrated considerable success on mice, carried out by a team at Harvard Medical School led by Zhigang He, takes a more sophisticated biotechnology approach. The drug being trialled contains a compound called CLP290 with activates the protein KCC2. The KCC2 protein is essential to neuronal function and after a spinal injury the body produces it in much smaller quantities. It was thought that this could hold the key to explaining why remaining healthy nerves stayed shut down.
As Professor He explains:
“A lot of connections are still there but it’s kind of like a relay. Imagine you cut off all direct flights from London to Boston. You can imagine you might still be able to fly there but going via Finland. The question is how to activate these dormant connections.”
After numerous experiments trialling different compounds, it was discovered that CLP290 resulted in 80% of mice with severe spinal cord injuries that had left them paralysed regaining the ability to walk. This end result was linked to the activation of the KCC2 protein. The team are still a long way from proving that the same, or similar, approach would work on humans, but are ‘very excited’.
The research being carried out by Professor He’s team is just one of the different ways biotechnology scientists are currently exploring how to reconnect nerves or stimulate their regrowth. While spinal injuries remain one of the most challenging to medicine, recent breakthroughs, especially those in the biotech sector, give hope of significant progress being achieved in the foreseeable future.