Scientist in the U.S have developed a drug that could help paralysed victims of spinal cord injury regain their ability to move.
In research conducted by Case Western Reserve scientists, the drug allowed activation of paralysed muscles in 80% of animals with spinal cord injury. The animals regained the ability to walk, balance, or urinate, with some animals regaining all three of these functions.
The compound, which was administered to the animals via daily injection, is referred to as intracellular sigma peptide (ISP). The peptide is believed to reconnect damaged nerve connections and restore their ability to transmit the electrical impulses required for the control of body movements.
“This recovery is unprecedented,” said Jerry Silver, lead author of the study and Medical Professor of Neurosciences at Case Western Reserve University.
For any spinal cord-injured patient today, it would be considered extraordinary to regain even one of these functions, especially bladder function.
After a spinal cord injury, proteins called proteoglycans gather in the scar tissue that forms around the site of injury. An excess accumulation of these proteins causes impenetrable nets to form in the cellular matrix that surrounds synapses in the brain and spinal cord. This creates a sticky barrier that prevents severed nerve fiber tips from reaching their synaptic connections – connections that are essential for the electrical transfer of information needed for body movement.
The ISP compound moves towards and penetrates this scar tissue and appears to switch off the neuron’s proteoglycan receptor. This enables neural communication to be restored across what would have otherwise been a formidable barrier.
As reported in the journal Nature, the scientists found that 21 of 26 animals injected with ISP over several weeks regained at least one of the three functions assessed (balance, walking and urination). Some of the animals regained all three abilities.
“There are currently no drug therapies available that improve the very limited natural recovery from spinal cord injuries,” said Lyn Jakeman from the National Institute of Neurological Disorders and Stroke.
This is a great step toward identifying a novel agent for helping people recover.
Silver and colleagues say that if the drug is successful in larger trials, it could be used either as a standalone treatment or alongside other therapies to give patients with spinal cord injury the best chance of recovery. The drug may also provide a potential new therapy for other diseases where destructive scarring causes problems such as multiple sclerosis and heart attack. Furthermore, because ISP can penetrate tissue, the treatment can be administered systemically, without requiring injection directly into the spinal cord.
Spokesperson for the UK’s Spinal Injuries Association, Dan Burden, said that the possibility of a drug treatment as opposed to surgery or the use of electrodes is particularly promising.