Glial cells send 'care packages' including protective proteins and genetic information to nerve cells
Researchers at Johannes Gutenberg University Mainz (JGU) have discovered a new form of communication between different cell types in the brain. Nerve cells interact with neighboring glial cells, which results in a transfer of protein and genetic information. Nerve cells are thus protected against stressful growth conditions. The study undertaken by the Mainz-based cell biologists shows how reciprocal communication between the different cell types contributes to neuronal integrity. Their results have been recently published in the journal PLOS Biology.
Brain function is determined by the communication between electrically excitable neurons and the surrounding glial cells, which perform many tasks in the brain. Oligodendrocytes are a type of glial cell and these form an insulating myelin sheath around the axons of neurons. In addition to providing this protective insulation, oligodendrocytes also help sustain neurons in other ways that are not yet fully understood. If this support becomes unavailable, axons can die off. This is what happens in many forms of myelin disorders, such as multiple sclerosis, and it results in a permanent loss of neuron impulse transmission.
Like other types of cell, oligodendrocytes also secrete small vesicles. In addition to lipids and proteins, these membrane-enclosed transport packages also contain ribonucleic acids, in other words, genetic information. In their study, Carsten Fr-hbeis, Dominik Fr-hlich, and Wen Ping Kuo of the Institute of Molecular Cell Biology at Johannes Gutenberg University Mainz found that oligodendrocytes release nano-vesicles known as 'exosomes' in response to neuronal signals. These exosomes are taken up by the neurons and their cargo can then be used for neuronal metabolism. "This works on a kind of 'delivery on call' principle," explained Dr. Eva-Maria Kr-mer-Albers, who is leading the current study. "We believe that what are being delivered are 'care packages' that are sent by the oligodendrocytes to neurons."