Introducing the brain: skin prick instant sensation (Introduction)

by David Turell , Saturday, March 27, 2021, 20:12 (1335 days ago) @ David Turell

Since the brain cannot produce new cells except in the hippocampus, damage control must be precisely handled to protect existing neurons:

https://www.sciencedaily.com/releases/2021/03/210326104659.htm

"When the brain suffers injury or infection, glial cells surrounding the affected site act to preserve the brain's sensitive nerve cells and prevent excessive damage. A team of researchers from Charité -- Universitätsmedizin Berlin have been able to demonstrate the important role played by the reorganization of the structural and membrane elements of glial cells.

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"Following brain injury or infection, various cells have to work together in a coordinated manner in order to limit damage and enable recovery. 'Astrocytes', the most common type of glial cell found in the central nervous system, play a key role in the protection of surrounding tissues. They form part of a defense mechanism known as 'reactive astrogliosis', which facilitates scar formation, thereby helping to contain inflammation and control tissue damage. Astrocytes can also ensure the survival of nerve cells located immediately adjacent to a site of tissue injury, thereby preserving the function of neuronal networks. The researchers were able to elucidate a new mechanism which explains what processes happen inside the astrocytes and how these are coordinated.

"'We were able to show for the first time that the protein 'drebrin' controls astrogliosis," says study lead Prof. Dr. Britta Eickholt, Director of Charité's Institute of Biochemistry and Molecular Biology. "Astrocytes need drebrin in order to form scars and protect the surrounding tissue."

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"To enable scar formation, drebrin controls the reorganization of the actin cytoskeleton, an internal scaffold responsible for maintaining astrocyte mechanical stability. By doing so, drebrin also induces the formation of long cylindrical membrane structures known as tubular endosomes, which are used in the uptake, sorting and redistribution of surface receptors and are needed for the defensive measures of astrocytes. Summing up the researchers' findings, Prof. Eickholt says: "Our findings also show how drebrin uses the dynamic and versatile cytoskeleton as well as membrane structures to control astrocyte functions which are fundamental to the defense mechanism against injury.'"

Comment: We see a specially designed mechanism to protect the damaged brain. In all of the articles I present of this type we see the effects of the specific protein, but never learn just how the protein acts at the molecular level to cause the result. We must use living tissue and use changed DNA to understand the various steps, but we are always at the outside as observers, while the nitty-gritty remains unknown. Thus the details are not present and life remains a black box.