By Gitty Boshnack, Science and Technology Editor
The nervous system is the control center of the entire body. The spinal cord and brain are the main organs of the nervous system. The brain sends the messages, and the spinal cord delivers them. But what happens when the spinal cord is injured? The pathways that these messages take are blocked, resulting in paralysis and palsies.
Samuel I. Stupp at Northwestern University has discovered an injectable therapy to treat and repair spinal cord injuries. This injection is composed of bioactive molecules that, upon injection, will gel into a network of fibers that will act as an extracellular matrix that can attach to receptors that will communicate with cells. This is known as a biological scaffold. The goal is to maintain control of 100,000 bioactive molecules at once. The network of these many gel-like fibers is known as a supermolecule. These molecules “dance” and move out of supermolecules, and through this, they can communicate better with intracellular receptors. These molecules dance in the darkness of destroyed tissue and enable movement. The more agile these fibers are, the more opportunity they have to connect with other healthy nerves and tissues. This is because healthy cells and their receptors are in constant motion, so if the scaffolds are not moving fast enough, they will not be able to “dance in sync” with the healthy tissue, impeding cellular communication.
When the molecules on these scaffolds connect to extracellular receptors, they stimulate two things. Firstly, axon regeneration, and secondly, neural accessory cell growth. Axon regeneration is crucial for the transmitting of messages. The axons send the messages away from the neuron to other neurons. The signal sent by the molecules prompts the axons to regenerate. Neural accessory growth is vital for infrastructural reasons. This means that you need the proper machinery to repair a neuron after it’s damaged, such as cells that stimulate the growth of blood vessels and the production of myelin. Myelin is like a wiretap that wraps around the axon and helps transmit messages faster. Specifically, in damaged nerve cells, myelin protects the axon from the scarring of neighboring tissue, contributing to inhibited cellular communication.
Both these contributions cause improvements in blood vessel growth, axon regeneration, increased myelin production, survival of motor neurons (neurons that aid with movement), less mutation in glial cells (which are the insulators of the nervous system), and functional recovery.
Stupp believes that this therapy can be used for diseases like ALS or stroke where the spinal cord is damaged, similar to how it is in cases of trauma. However, understanding and controlling molecular assembly processes is more significant because molecular dancing can be applied more broadly in other biological research.
Not only have Stupp and his team of researchers learned to make molecules dance, they are potentially enabling thousands of paralyzed patients to dance again.