Research on new medicine brings hope of cure for paralysis

Scientists in the United States have developed a new type of drug that promotes cell regeneration and reversed paralysis in rats with spinal injuries, allowing the animals to walk again after four weeks of treatment.

The research was published in the journal Science on Thursday (11) and the team responsible, from Northwestern University, said they hope to present their treatment next year to the US drug regulatory agency, the FDA, in order to start the tests in humans.

“The aim of our research was to develop a transferable therapy that could be used in hospitals to prevent paralysis in people from trauma and illness,” study leader Samuel Stupp told AFP.

Curing paralysis is an age-old goal of medicine, and other groundbreaking research in the field includes experimental stem cell treatments to produce new neurons, gene therapy that commands the body to produce certain proteins to aid nervous system recovery, and direct injection of proteins .

Stupp’s team, in turn, used nanofibers to mimic the architecture of the “extracellular matrix”, a network of molecules that develop naturally around cell tissue.

Each nanofiber is 10,000 times thinner than a human hair, and they are made up of hundreds of thousands of molecules called peptides, which transmit signals to promote nerve regeneration.

The therapy in gel form was injected into tissue surrounding the spinal cord of laboratory rats 24 hours after making an incision in their spines.

The team decided to wait a day because humans who suffer severe spinal cord injuries from car accidents, gunshots and other reasons also take a long time to receive treatment.

Four weeks later, the rats that received the treatment regained their ability to walk almost as well as they had before the spinal cord injury, while those that didn’t did not walk again.

The impact of the treatment at the cellular level was then evaluated by the team, who found an impressive improvement in the spinal cord.

Extensions of neurons called axons have regenerated and scar tissue, which can act as a physical barrier that prevents regeneration, has been shown to be significantly reduced.

In addition, a protective sheath of axons, which are important for transmitting electrical impulses, regenerated, blood vessels formed to carry nutrients to the injured cells, and more motor neurons survived.

dancing molecules

A key finding by the team was that creating a certain mutation in the molecules intensified their collective movements and improved their effectiveness.

That’s because the receptors on neurons are naturally in constant motion, Stupp explained. Thus, increasing the movement of therapeutic molecules with nanofibers helps to connect them more effectively with their moving targets.

The researchers even tested two versions of the treatment – ​​one with the mutation and one without – and found that the mice that received the modified version regained more mobility.

The gel developed by the scientists is the first of its kind, and it could be the first of a new generation of drugs known as “supramolecular drugs”, because the therapy involves the union of several molecules instead of a single one, indicated Stupp.

According to the team of scientists, the treatment is safe because the materials degrade in a matter of weeks and become nutrients for the cells.

Stupp said he hopes the studies can move quickly to humans, without the need for further testing on animals such as monkeys, because the nervous system is very similar across mammalian species, and “there’s nothing to help patients with spinal cord injuries, which is a big problem.”

According to official statistics, about 300,000 people live with spinal cord injuries in the United States alone. Their life expectancy is shorter than that of people without this type of injury and has not improved since the 1980s.

“The challenge will be how the FDA will review these therapies, because they are completely new,” commented Stupp.