The contacts between neurons (synapses) with five times smaller in the areas of the brain that suffer from Alzheimer’s, according to a study by the Higher Council for Scientific Research (CSIC) published in the Journal of Alzheimer’s Disease.
Human brains affected by Alzheimer’s disease are characterized by having regions with certain pathological structures associated with the disease, such as amyloid plaques. An investigation led by the Higher Council for Scientific Research (CSIC) has just shown that the number of synoptic contacts between neurons in these areas are up to 83% lower than in those far from the influence of these structures.
The finding, published in the March issue of the Journal of Alzheimer’s Disease, has been made with three-dimensional reconstructions made from samples of different brain regions from five donors who suffered from Alzheimer’s disease while alive. The results, in addition to showing a notable decrease in synapses in the affected regions, indicate that, in the latter, the spatial distribution of synaptic contacts is concentrated in the free spaces left by the disease-associated plaques. In contrast, in brain regions more distal to these structures, synaptic contacts are randomly distributed.
The researcher at the Instituto Cajal Javier de Felipe of the CSIC, who develops his activity at the Center for Biomedical Technology of the Polytechnic University of Madrid and who has led the research, considers that “these synaptic alterations involve a disturbance in the interneuronal connections, which it could explain, in part, the cognitive deterioration associated with Alzheimer’s disease ”.
This ailment affects some 35.6 million people in the world and, despite having been discovered more than 100 years ago, De Felipe points out that “even today it is unknown how and why certain normal cortical circuits are altered and induce deterioration cognitive”.
