The glial cells outnumber our neurons

It is true, let’s face it, when we think of the brain we are talking about almost always that of neurons. Yet they would be nothing without their accomplices, who support, stimulate, feed and protect : the glial cells. It is this that is come to plead Yves Agid, neurologist, co-founder of the Institute of the Brain and spinal Cord (ICM), at the opening of the 3rd edition of S3Odéon (S3) for “health science” company”). On the stage of the Odeon theatre, before a packed audience, he has, in seven minutes on the clock, drew up the portrait of these cells to the fantastic and unknown. In an interview behind the scenes, Yves Acted said more to Science and the Future – see video below.


“We were talking about the brain is neural, it is now necessary to speak of the brain glial !”

Glial cells are 150 billion, or more numerous than neurons in the brain (less than 100 billion). They are of three types : microglia, the immune cells that ensure the defence of the brain. The oligodendrocytes that surround a sleeve of the fibers issuing of the neuron, to speed up the electrical transmission. And finally astrocytes, these super-cells to do everything, companions essential neurons.

Unlike neurons, astrocytes do not have electrical activity. “They are silent “, said Yves Agid. This would explain the little popularity they have been addressed in the neuroscience of the 20th century. However, according to the neurologist, “if we look at the evolution, the more one has, the more one is intelligent !”. And to quote the slug, which has only one glial cell for six neurons, whereas the human has an almost one-for-one, depending on the areas of the brain.

These cells serve to protect the neuron, to feed it, clean it, and dialogue with him via neurotransmitters. Better, adds the researcher, today we discover that they play a role even in the behavior ! In animal studies, when you alter the biology of these cells, there are changes in behaviors as complex as the memory !

Also, when they malfunction, these cells ignored play a role in diseases of the nervous system and in particular neurodegenerative diseases. Thus, there is a field of investigation considerably. To find new treatments by acting on neurons but also the glial cells.


The Stopru