Oldest specimens of human neural tissue
Today it is one of the oldest specimens of human neural tissue ever to be discovered in the UK and it has scientists perplexed. According to carbon dating, the man died somewhere between 673 and 482 BCE. So how was that piece of his brain preserved?
To try and figure out what made the remaining organic material so unique that it could survive intact for so long, researchers took a closer look at the nature of its proteins.
In order to operate, the brain needs to be well supported on a cellular level. It stays supported through a network of connections within the complex weave of neurons and their long bodies.
It is intermediate filaments (IFs) that maintain these connections in living brains. And, under the right circumstances, these IFs can go on to exist even after cells have died.
In the Heslington brain, researchers found weaves of IFs that resembled the long threads of axons making up a living brain. The only difference was that they were shorter and narrower.
Further analysis revealed a large number of neural structures belonging to 'helper' cells such as astrocytes. The team now had to figure out why these astrocyte IFs were so good at self-preservation.
What they found was that it was a chemical that blocks destructive enzymes following death that was responsible for their preservation.
Essentially, they concluded that there was nothing special about the Heslington brain. Rather, some foreign entity must have entered the grave which made the brain preserve itself.
"Combined, the data suggest that the proteases of the ancient brain might have been inhabited by an unknown compound which had diffused from the outside of the brain to the deeper structures," conclude the researchers in their report.