Protein involved in reactive astrogliosis identified!

Scientists have found a genetic trigger that may improve the brain's ability to heal from a range of debilitating conditions, from strokes to concussions and spinal cord injuries.

A new study in mice shows that turning on a gene inside astrocytes results in a smaller scar and - potentially - a more effective recovery from injury.

"We've known that astrocytes can help the brain and spinal cord recover from injury, but we didn't fully understand the trigger that activates these cells," senior author said. "Now we'll be able to look at whether turning on the switch we identified can help in the healing process."

The study published in Cell Reports found that the LZK gene of astrocytes can be turned on to prompt a recovery response called astrogliosis, in which these star-shaped cells proliferate around injured neurons and form a scar.

Scientists deleted the LZK gene in astrocytes of one group of injured mice, which decreased the cells' injury response and resulted in a larger wound on the spinal cord. They overexpressed the gene in other injured mice, which stimulated the cells' injury response and resulted in a smaller scar. Overexpressing the gene in uninjured mice also activated the astrocytes, confirming LZK as a trigger for astrogliosis.

The senior author said a smaller scar likely aids the healing process by isolating the injured neurons, similar to how isolating a spreading infection can improve recovery. "But we don't know under what circumstances this hypothesis is true because until now we didn't have an easy way to turn the astrocyte reactivity on and off."

Further study is needed to analyze whether a compact scar tissue indeed improves recovery and how this process affects the neurons' ability to reform connections with each other.

http://www.utsouthwestern.edu/newsroom/articles/year-2018/gene-therapy-stroke.html