Friday, April 21, 2017
Early signs of Alzheimer’s detected in cerebrospinal fluid - NEUROSCIENCE
Little is known about the role of the brain‘s immune system in Alzheimer’s disease. Researchers at the Munich site of the German Center for Neurodegenerative Diseases (DZNE) and the hospital of the Ludwig Maximilian University (LMU) Munich have found an early immune response in individuals with a genetic predisposition to Alzheimer‘s: their brain’s showed abnormal immune reactions as early as about seven years before the expected onset of dementia.
These results demonstrate that in cases of Alzheimer‘s, inflammatory processes in the brain evolve dynamically and are precursors of dementia. These immune responses can be detected by means of a protein in the cerebrospinal fluid, offering physicians the possibility to trace the progression of the disease. The study results are published in the journal “Science Translational Medicine”.
The scientists headed by Prof. Christian Haass and Prof. Michael Ewers were able to detect an increasing immune activity of the brain by measuring levels of the protein “TREM2” in the cerebrospinal fluid. TREM2 is segregated by certain immune cells of the brain - called microglia - and thus reflects their activity. In cases of the inherited form of Alzheimer’s disease, the timing for the onset of dementia can be precisely predicted. The researchers were therefore able to monitor the rise of TREM2 levels years before the expected occurrence of dementia symptoms.
“The activity of the microglia is stimulated by dying brain cells, not by the deposits of amyloid proteins, called plaques, which also occur in Alzheimer’s disease,” Haass notes. ”The microglia may have a protective function, which however comes to a standstill as the disease progresses. We are therefore searching for drugs to increase the activity of the microglia.”
Gif: flow of the CSF - sagittal plane - ( CSF is produced by choroid plexus of each ventricle)