This recording gives an insight into the white matter of the brain. It gets its whitish appearance from the turquoise myelin, the covering substance that surrounds the conduction pathways between the brain cells.
Myelin is a whitish protective layer made of proteins and fats that surrounds the extensions of our nerve cells, the axons. This layer isolates the nerve tracts and thus helps ensure that the electrical impulses that are passed on from one nerve cell to the next are not weakened. This makes the nerve conduction in our body effective even over long distances.
But myelin is also found in our brain – such a neural nerve sheath shows our absorption. In our thinking organ, the substance forms an insulating layer around the lines that connect our brain cells and areas with one another. This gives the layer in which these neuronal connections cluster a whitish color – it is therefore also known as white brain matter. “Everyone knows the gray matter, but few are familiar with the white matter of the brain,” says Arthur Butt of the University of Portsmouth.
This white brain substance and with it the myelin sheath of the nerve tracts is crucial for the functioning of our brain. If the myelin is damaged or broken down, as in multiple sclerosis or dementia, important signals can be misdirected or not arrive. Myelin is formed by special cells, the oligodendrocytes, which are constantly developing from progenitor cells. In old age, however, this only happens very slowly, so that less myelin is produced and the lack of white brain matter leads to mental decline.
Researchers led by Butt and Andrea Rivera from the University of Portsmouth have now investigated why the formation of oligodendrocytes in the aging brain slows down. To do this, they compared the genome of a young mouse brain with that of a senile mouse. In doing so, they came across a gene that apparently plays a key role in the replication of the myelin-producing cells.
In the next step, the scientists now want to clarify whether this gene also controls the development of oligodendrocytes in humans. If this is confirmed, the gene could offer a starting point for stimulating myelin production in the aging brain and thus “rejuvenating” the brain. This could possibly also help to delay or alleviate neurodegenerative diseases.