One of the reasons people rarely recover from spinal cord injury is the scar tissue that develops, preventing nerve cells from reconnecting. But a new study from Zhigang He, PhD, of the F.M. Kirby Neurobiology Center at Boston Children’s Hospital, demonstrated a way to minimize scar cell formation in adult mice after a spinal cord injury. The study, published in Nature, offers insights for new approaches to treating spinal cord injuries.
Dynamic networks that specialize in the transmission of information generally consist of multiple components, including not only primary processors, like computers, for example, but also numerous support applications and services. The human nervous system is fundamentally very similar—neurons, like computers, process and transmit information, sending molecular signals through axons to other neurons, all of which are supported by non-neuronal components, including an array of cells known as glia.
Spinal cord injuries can have lasting and devastating effects on mobility and cognitive function due to permanent nerve cell damage or death. A new study from researchers at Temple University now shows how neuronal connections can be regenerated after such injuries.
Neurons contain structural appendages called axons which form connections with each other throughout the brain and greater parts of the body. These axons form an interconnected communication system that regulates sensory and motor functions; injury to axons can result in their breakage, leading to irreversible damage.
JNCASR researchers find out that it has the ability to reprogramme damaged nerve cells
A small molecule synthesised by researchers at the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), in Bengaluru, may have the power to make patients paralysed by spinal cord injury walk again.
An international team of researchers who worked with the molecule demonstrated that it has the ability to reprogramme nerve cells damaged during a spinal cord injury in animals, recover sensory and motor functions.
Humans can regenerate their peripheral nerves (PNS), but the regenerative ability does not extend to the central nervous system (CNS). So, what changed? Previously, the focus had been on identifying the cellular and molecular contributors that differentiate this regenerative ability in CNS vs. PNS. But now there seems to be a shift towards recognizing the underlying genetic makeup differences between the two.
Researchers at Washington University School of Medicine in St. Louis have identified some of the critical steps taken by peripheral nerves – those in the arms and legs – as they regenerate.
In a collaboration led by EPFL (Ecole polytechnique fédérale de Lausanne) in Switzerland and UCLA (University of California at Los Angeles) in the USA, scientists have now understood the underlying biological mechanisms required for severed nerve fibers to regenerate across complete spinal cord injury, bridging that gap in mice and rats for the first time.
The adult mammalian body has an incredible ability to heal itself in response to injury. Yet, injuries to the spinal cord lead to devastating conditions, since severed nerve fibers fail to regenerate in the central nervous system. Consequently, the brain’s electrical commands about body movement no longer reach the muscles, leading to complete and permanent paralysis.
The molecule inhibits adult axon regeneration, but appears to stimulate young neurons
Recovery after severe spinal cord injury is notoriously fraught, with permanent paralysis often the result. In recent years, researchers have increasingly turned to stem cell-based therapies as a potential method for repairing and replacing damaged nerve cells. They have struggled, however, to overcome numerous innate barriers, including myelin, a mixture of insulating proteins and lipids that helps speed impulses through adult nerve fibers but also inhibits neuronal growth.
Searching the entire genome, a Yale research team has identified a gene that when eliminated can spur regeneration of axons in nerve cells severed by spinal cord injury.
“For the first time, the limits on nerve fiber regeneration were studied in an unbiased way across nearly all genes,” said Stephen Strittmatter, the Vincent Coates Professor of Neurology and senior author of the study appearing April 10 in the journal Cell Reports. “We had no idea whether we knew a lot or a little about the mechanics of nerve cell regeneration.”
Researchers grew human spinal cord neurons from stem cells and injected them into healthy mice, where they successfully connected with other neurons.
Discovery could be key to treating brain and spinal cord injury
A foray into plant biology led one researcher to discover that a natural molecule can repair axons, the thread-like projections that carry electrical signals between cells. Axonal damage is the major culprit underlying disability in conditions such as spinal cord injury and stroke.
Andrew Kaplan, a PhD candidate at the Montreal Neurological Institute and Hospital of McGill University, was looking for a pharmacological approach to axon regeneration, with a focus on 14-3-3, a family of proteins with neuroprotective functions that have been under investigation in the laboratory of Dr. Alyson Fournier, professor of neurology and neurosurgery and senior author on the study.