Source: UT Southwestern Medical Center
Summary: Researchers 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.
Astrocytes are the star-shaped glial cell of the central nervous system (CNS) which provide structural and metabolic support, regulate neurotransmitter uptake and synaptic transmission, and help maintain the blood-brain barrier. Under pathological conditions such as stroke, epilepsy, traumatic injury and neurodegenerative disorders, the astrocytes become reactive, undergoing a spectrum of phenotypic changes. Researchers from the UT Southwestern Medical Center 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. They 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. The study findings were published in the journal Cell Reports.
The research team 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. A smaller scar likely aids the healing process by isolating the injured neurons, similar to how isolating a spreading infection can improve recovery. 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.
Lead author, Dr. Meifan Amy Chen said, “It has been a big mystery whether increasing astrocyte reactivity would be beneficial”, “The discovery of LZK as an on switch now offers a molecular tool to answer this question.”
More Information: Meifan Chen et al, “Leucine Zipper-Bearing Kinase Is a Critical Regulator of Astrocyte Reactivity in the Adult Mammalian CNS”, Cell Reports (2018). DOI: 10.1016/j.celrep.2018.02.102