amyloid beta

chemical compound

Also known as: beta-amyloid

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Last updated

July 17, 2026

Quick Summary

Amyloid beta is a protein that plays a key role in Alzheimer's disease. In individuals with Alzheimer's, amyloid beta proteins clump together, forming sticky plaques in the brain. These plaques are toxic to brain cells, leading to their destruction and the loss of connections between neurons. This damage impairs cognition and memory.123

While amyloid beta is a normal component of nerve cells, its abnormal accumulation is a hallmark of Alzheimer's disease. Treatments like lecanemab aim to reduce amyloid beta levels, potentially slowing disease progression in early stages.32

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Alzheimer disease
Neuritic plaques and neurofibrillary tangles
…of a sticky protein called amyloid beta (or beta-amyloid). This protein is derived from a larger molecule called amyloid precursor protein, which is a normal component of nerve cells. Neurofibrillary tangles are twisted protein fibres located within nerve cells. These fibres consist of a protein, called tau, that normally occurs…
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…of a sticky protein called amyloid beta (or beta-amyloid). This protein is derived from a larger molecule called amyloid precursor protein, which is a normal component of nerve cells. Neurofibrillary tangles are twisted protein fibres located within nerve cells. These fibres consist of a protein, called tau, that normally occurs…
Read More