What are glial cells ?
Glial cells are the cells that support the neurons (nerve cells) in your brain, they are the supporters of your brain health =D.
There are five types of glial cells:
Astrocytes (also named astroglia) are the most common type of glial cell, and they play multiple roles in the brain such as forming the Blood-Brain Barrier, which is basically the brain filtering system to keep anything that isn’t supposed to be there, out. The BBB can be described as your brain's first line of defense, in and on itself it can filter “misfolded” proteins, and the BBB itself is protected by a barrier the “Glial barrier. You can imagine the glial barrier as the image above, an astrocyte using the end of its tentacles to wrap around “stuff”.
The “tight” junctions formed by this glial barrier are not tight enough to stop tau, and amyloid beta from passing through, but the tight endothelial junctions at the BBB prevent. Failure (permeability) in the BBB = neurological inflammation, progressive neurodegeneration.
They also regulate neurotransmitters and recycle them after they are done, they also clean up the cell waste after that. Another two important functions are regulating the activity of axons (the long part of neurons and nerves cells that transmits messages between them), and regulating brain energy metabolism.
https://hiddencomplexity.substack.com/p/the-brains-housekeeping-glymphatic