Though all mice studies should be viewed with quelled excitement, a new Yale School of Medicine study shows that scientists were able to reverse Alzheimer’s disease with a single dose of a drug compound.

The researchers gave mice with Alzheimer’s a compound called TC-2153, which prohibits a protein called STEP (Striatal-Enriched tyrosine Phosphatase) from interfering with the brains’ ability to learn and make memories. Synapses in the brain need to strengthen so that the brain can turn short-term memories into long-term memories, but STEP prevents synapses from doing so, and this can lead to neurological disorders including Alzheimer’s.

The mice with memory loss who were given the compound were able to recover their cognitive function, and the researchers say they were indistinguishable from normal, control mice. The researchers, who published their recent work in the journal PLOS Biology, are now testing the compound’s ability in other animals.

It will still be a long time before a compound like this is tested in humans, but the preliminary finding is encouraging since very few experiments have actually been able to reverse the disease, which currently affects about five million Americans and is expected to grow dramatically in coming years.

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