Sentences with phrase «glial scar»
A "glial scar" refers to a type of scar tissue that forms in the brain or spinal cord as a result of injury or disease. Glia are specialized cells in the nervous system that help support and protect neurons. When the brain or spinal cord is damaged, glial cells form this scar to seal off the affected area and prevent further injury. However, this scar can also hinder the regeneration of neurons, making it difficult for the nervous system to fully recover. Full definition
For example, it has long been known that astrocytes within glial scar tissue contribute to the failure of axon regeneration across sites of traumatic brain or spinal cord injury [1]--[6].
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These «reactive glial cells» initially build a defense system to prevent bacteria and toxins from invading healthy tissues, but this process eventually forms glial scars that limit the growth of healthy neurons.
«For 20 years, we have been applying technologies to prevent glial scarring in hopes of promoting nerve fiber regeneration, repair and recovery, but never observed a positive effect,» said Sofroniew, a professor of neurobiology at the David Geffen School of Medicine at UCLA.
Remarkably, in the normal mice, the approach stimulated robust regrowth of the stalled spinal axons past glial scars and through the injury site.
Some earlier studies had indicated that reactive astrocytes are necessary for recovery following brain or spinal cord injury despite astrocytes» association with the formation of glial scars.
«Now we find that disrupting glial scars actually harms nerve fiber regeneration that can be stimulated by specific growth factors.»
The research also revealed glial scars» beneficial role in an experiment in which the scientists softly flog injured neurons into regenerating — a strategy Sofroniew likens to a «carrot and a stick» approach.
This is because, after injury, spinal nerve fibers do not regrow past such glial scars and appeared to be «stalled» within them.
So several years ago, Chen's lab tested new ways to transform glial scar tissue back to normal neural tissue.
Nerve glial antigen 2 expressing neural cells - derived from ESCs may allow for delayed spinal cord regeneration through the penetration of the protective glial scar
hGDAsCNTF also expressed high levels of neurite - outgrowth inhibitory chondroitin sulfate proteoglycans, phosphacan and CSPG4, as well as the transcription factor Olig2 - all of which have been found to be upregulated in glial scar associated astrocytes.
In addition to inflammation, previous microelectrode brain implants made of silicon or microwire have caused neuronal death and glial scarring, which is damage to connective tissue in the nervous system.
«Spinal cord regeneration might actually be helped by glial scar tissue: Research finds that nerve cells regrow better when glial scarring is left intact.»
In a study using mice, Dr. Michael Sofroniew and colleagues found that the glial scar tissue that forms after spinal cord damage might actually favor nerve cell regeneration.
The problem with reactive glial cells is that they often stay at the injury site, forming a glial scar and preventing neurons from growing back into the injured areas,» he explained.
The role of gliosis is controversial since it has been shown to provide neuroprotection and repair as well as being harmful by forming a glial scar (particularly the proliferative form)-- or possibly both.
The key goal of therapy during the acute stage is to reduce the scar tissue within the damaged spinal cord «glial scar» that may impede future healing.