阿尔茨海默氏症,萎缩脑细胞 z-bo 2020-10-21 368

　　For the first time, scientists have discovered mysterious atrophied cells in the human brain and confirmed that it seems to be associated with Alzheimer's disease.

　　"We don't know whether they are the cause or the result." said Marie-ève Tremblay from Laval University, Quebec, Canada. She recently presented this discovery at the Translational Neuroimmunology Conference in Montana.

　　These cells appear to be atrophied forms of microglia. Microglia keep the brain tidy and free from infection, and this is usually achieved by trimming unwanted brain connections or destroying abnormal and infected brain cells.

　　However, the cells found by Tremblay looked much darker under an electron microscope and appeared to be more destructive. "It took us a long time to recognize them." Tremblay said that these shrunken cells did not show the same coloring chemicals that usually make microglia visible under a microscope.

　　Compared with normal microglia, these darker cells seem to surround the neurons and the synapses that connect them more closely. "They are extremely active near the synapses." Tremblay said, where these microglia appear, the synapses often atrophy and are in the process of degeneration.

　　Tremblay discovered these dark microglia cells for the first time in mice, and confirmed that their numbers increase as the mice get older. At the same time, these cells seem to be related to many things including stress, neurodegenerative diseases-Huntington's disease, and mouse models of Alzheimer's disease. "The dark microglial cells in Alzheimer's mice are 10 times that of control mice," Tremblay said.

　　Now, she has detected these cells in the human body for the first time. Tremblay analyzed the brain of a patient with Alzheimer's who died at the age of 45 and found that the dark microglia in it were about twice as large as the brains of healthy people of the same age.