Synapse loss in Alzheimer’s disease

Synapse loss is the hallmark of Alzheimer’s disease that correlates best with impaired memory, and is thought to occur even before the onset of clinical symptoms.

Alzheimer’s disease pathology

Pathological hallmarks of Alzheimer’s disease

Alzheimer’s disease is characterised by beta-amyloid plaques, neurofibrillary tangles, neurone loss and synapse loss [1-4]. Compared with the other hallmarks of Alzheimer’s disease, synapse loss correlates best with impaired memory, and is believed to occur early in the disease process, even before the onset of clinical Alzheimer’s disease symptoms [2-4].


Reduced number of synapses in MCI and AD compared with control[3]

NUT177_Section 2.2

Adapted from Scheff et al. (2006)


Synapse loss and memory


Adapted from Scheff et al. (2006)

While synapse loss occurs during normal ageing, it is far more pronounced in Alzheimer’s disease [1-3,5]. The cognitive changes that occur in Alzheimer’s disease patients are related to the loss of functional connections in the brain associated with synapse loss [1]. A correlation has been observed between the number of synapses and memory, with memory performance declining as the number of synapses decreases [3]. A specific combination of nutrients is required for the formation of new synapses [6-16]


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