Alzheimer Disease

Alzheimer disease is a progressive, degenerative disease that attacks the brain and results in impaired memory, thinking and behavior. It is a disease of the old: up to age 75, less than 5% of people are affected; above 85, about 50% of people are affected. The disease will become more and more common as the population ages. Remember too that the burden of care, typically born by the sufferer's family, is considerable.

The disease was discovered in 1906 by Alois Alzheimer, a German neurologist. Abnormal structures called neurofibrillary tangle form inside the brain's neurons, disrupting their normal function. First affected tend to be those areas of the brain that influence short-term memory; later, the disease spreads to other areas.

The illustration on the right shows how neuro-fibrillary tangles form inside neurons. Each new piece is a tau protein. It binds to the tangle, and then gets truncated. Afterwards another tau protein can attach and be truncated, and another, and so on. The tangle grows in length; when a neuron has too much tangle inside, it can no longer function properly.

We have found that a family of substances similar to an existing drug, methylene blue, reverse this tangle-formation process. The next stage in the research is to repeat the experiment in actual living neurons, and then to screen millions of related substances to find the one that has the highest efficacy and the lowest toxicity.

0.01% concentration of methyl blue, left to incubate for 6 hours. The tangle is still present. (Scale bar is 100nm)

0.1% methyl blue, examined after a short time. The tangles have begun to coarsen.

1% methyl blue. The tangles are coarsening and swelling.

1% methyl blue. The tangles are fragmenting.

1% methyl blue, left for 6 hours. The tangles have disappeared.

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