Amyloid & Tau: How proteins disrupt the brain

Alzheimer's disease is characterized by two prominent abnormalities in the brain: amyloid plaques and neurofibrillary tangles , also known as tau tangles .

Amyloid plaques are abnormal accumulations of a protein called beta-amyloid . This protein is present in small amounts in healthy brains, but in Alzheimer's, it forms sticky clumps between brain cells. These plaques can disrupt communication between cells and contribute to the death of brain cells.

Tau tangles are clumps of thread-like fibers inside brain cells. They consist of the protein tau , which normally helps to keep the cell structure stable. In Alzheimer's, this protein changes shape and begins to accumulate, causing the cell to lose its structure and function.

These protein accumulations are considered key features of Alzheimer's and constitute one of the theories regarding how the disease develops. However, it is important to note that scientists do not yet know exactly what the true cause of dementia is. Amyloid plaques and tau tangles may therefore be part of the story , but multiple factors likely play a role.

A combination of various causes is suspected, such as genetic predisposition, lifestyle, inflammatory responses in the brain, and disruptions in the immune system. More research is needed to better understand exactly how these processes interact and ultimately lead to neurological damage.

What we do know is that this damage contributes to the loss of memory, cognitive ability, and behavior, which is characteristic of dementia such as Alzheimer's.