Researchers from the Institute for Neurosciences (IN), a joint center of the Miguel Hernández University of Elche (UMH) and the Spanish National Research Council (CSIC), who are also part of the Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED) and the Alicante Institute for Health and Biomedical Research (ISABIAL), have developed a cellular fractionation protocol. This method allows for precise analysis of the proteins located in synaptic membranes and in membranes outside the synapses, known as extrasynaptic membranes, in human postmortem brains. In this study, recently published in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, the authors investigated NMDA receptors due to their importance in synaptic transmission and their special relevance in Alzheimer's disease.
Compared to healthy individuals, the results reveal that people with Alzheimer's disease exhibit decreased NMDA receptors in synapses and increased extrasynaptic membranes. Alzheimer's disease is characterized by progressive memory loss and affects communication between neurons. This process largely depends on synapses, where NMDA receptors play a critical role in learning and memory.
"Most NMDA receptors are found in synapses, where they enhance neuronal connections. However, those located outside the synapse are more associated with processes of toxicity and cell death, which may contribute to disease progression", explains Inmaculada Cuchillo Ibáñez, t.