Spinal Injury Drug Could Cure Paralysis By Sparking Nerve Growth

Researchers have developed a drug which could restore muscle and bladder function in people affected by paralysis following spinal cord injury.

The drug, Intracellular Sigma Peptide (ISP) works by freeing nerve fibers trapped in scar tissue following injury. The drug was developed after researchers identified a substance called proteoglycan that binds severed nerves to scar tissue, preventing them from forming useful nerve connections, NPR Blog reported. ISP targets proteoglycan.

"We're very excited at the possibility that millions of people could, one day, regain movements lost during spinal cord injuries," said Jerry Silver, senior investigator of the study, in a news release.

Silver and his team found that proteoglycans provide direction for nerves to grow normally but hinder nerve regeneration after injury. ISP works by preventing proteoglycan activation.

To test the drug, the research team injected it into severed nerve cells cultivated in a Petri dish. When they found the cells had been freed from scar tissue, they injected the drug under skin of 26 rats at the site of injury. After seven weeks of treatment, 21 rats were able to use their bladder, legs or both, Fox News reported.

Researchers learnt that the drug freed trapped nerve fibers but did not facilitate original restoration of nerve connections with the brain. Instead, the new growth was fuelling increased production of neurotransmitter serotonin in the spinal cord which in turn increased the magnitude of nerve signalling through intact nerve fibers, and the consequent improvement in muscle function.  

"It was amazing. The axons kept growing and growing. This is very promising. We now have an agent that may work alone or in combination with other treatments to improve the lives of many," said Dr Silver.

The findings of the study have been published in Nature.