Small glial cells that "devour memory" or allow memory regulation to follow

memories happen all the time, and forgetting is like a shadow. The sea mass is an important brain region responsible for memory coding and storage. Memory information is encoded in neurons, which we call memory imprinting cells. However, it is always elusive how memories fade over time.After more than 3 years of efforts, Zhejiang University School of Medicine Guyan Researcher Group and Wang Lang Associate Researcher Team first found that the small glial cells used for immunity by removing synapses caused memory forgetting, and further found that complement signaling path is involved in small glial cell-mediated forgetting. The study was published in science, one of the world's top journals.

immune cells are involved in memory loss"We electrically stimulated the mice with electric shocks in a particular scene to build a memory of the environment, and after 35 days we brought the mice back to the scene to observe their performance." The normal mice move around because they are curious about the environment, but if they have memories of fear, the mice will stay stiff, Gu said.The researchers measured memory retention in mice by calculating how long they remained stationary in units of time. Because of memory extraction in the body of the sea mass, the memory imprinting cells are activated mainly by encoding the relevant memory information. So the researchers found that forgetting in mice was accompanied by a decrease in the activation rate of memory-printed cells."As the main immune cells in the central nervous system, small glial cells account for about 10% to 15% of the total number of brain cells. A growing body of research shows that it also has important regulatory effects on nervous system development, neuron activity, and nerve loop function. Wang Lang laughs, uncovering the mystery of the decline in the activation rate of memory-printed cells, we decided to start with small glial cells to "solve the case".After a series of experiments on memory formation and extraction in mice that cleared small glial cells, the team found that the decrease in the reactivation rate of memory-printed cells was inhibited, and the inhibition effect on memory forgetting was very significant."The fear response in mice that removed small glial cells was more pronounced than in the control group, and they were at rest more than twice as long as the control mice." Gu said.

mechanism begins with molecular "navigation""The synactic connection between memory-printed cells is the 'warehouse' that stores memories." Gu Yan explained that the team should further analyze the specific mechanism by which small glial cells cause a decrease in the activation rate of memory-printed cells.Using immuno-staining and high-resolution imaging, the researchers found that small glial cells in the sea mass of adult mice still have the ability to devour synth structures. Memory forgetting was significantly blocked when the inhibited mice's glial cells were devoured. These results suggest that small glial cells mediate forgetting by "eating" synapses.By comparing experiments, they found that blocking the complement signaling path in memory-printing cells was very effective in suppressing memory forgetting and decreasing memory-printing cell activation. "Under high-resolution microscope imaging, you can see that the C1q-complement signal path is like a hound, responsible for finding and marking some of the synapses of the memory imprinting cells, so that the small glial cells are like having a navigation map, and eat a quasi." Mr Wang said.

to explore new targets for memory retentionIt is understood that the toothed back of the sea mass can constantly produce new neurons, which scientists call neurogenesic. The integration of newborn neurons that continue to develop in toothed echoes leads to the recombination and replacement of large numbers of synapses in the neural loops of the hema body, leading to the forgotten memory of previously established memories, especially in infernity.To find out the relationship between small glial cell-mediated forgetfulness and neurogenic interstmental forgetting, the researchers manipulated both the neural occurrence of the hema body and the small glial cells, and found that synhap removal of small glial cells was involved in forgotten caused by or unrelated to neurogenesic occurrence.The team concluded that synth phagocytosis in small glial cells may be a more common mechanism for forgotten in mammalian brain intermediaries where no nerves occur, or in areas of the brain where nerves do not occur."This work provides a forward-looking basis for studying the consolidation of long-term memory and the elimination of bad memory." Gu Yan told reporters that with the deepening of research, people may have a clearer understanding of the memory damage and memory loss caused by disease in the future.
(Science and Technology Daily)