Neuroscientists have found that microglia and astrocytes share responsibilities when removing the remnants of dead neurons: the first utilized the body of neurons and nearby spines and the second remote branches of the dendritic tree. For a timely response to the dying neuron to glial cells required receptor Mertk — in the absence of astrocytes is not polarized, and microglia later migrate to the dying cell. If failure is eliminated only microglia, astrocytes can compensate for its functions and to absorb the body nerve cells. In older mice, removing remnants of dead neurons is slower, but the reasons for this are not yet clear. Article published in the journal Science Advances.
Programmed cell death, or apoptosis, plays an important role in maintaining homeostasis, including the nervous system. The death of neurons in the brain regulates the number of cells and the ratio of their types, but in addition occurs with the pathology. The remains of the dead cells must be disposed of, otherwise it may develop an inflammatory or autoimmune response.
Eating dead cells are the phagocytes in the mammalian brain is microglia, and in some cases astrocytes. However, it is unclear how microglia and astrocytes respond to signals of apoptotic neurons and interact with each other, because “catch” the dying neuron and observe its utilization difficult.
Scientists from Yale school of medicine under the guidance of Jaime Grutzendler (Jaime Grutzendler) has developed a method that allowed in real time to observe the death of neurons, and phagocytes. Apoptosis was launched in certain cells of the mouse brain are on neurons illuminated with a laser beam, and they perished. Dying neurons and glio, which they destroyed, visualized using two-photon microscope.