It may not sound that much scientific but it is quite descriptive. The molecule we are talking about is called Anatoxin-a and is found in nature in the green algae in some form of cyanobacteria. We do not really know what purpose it serves, but luckily this molecule is quite unstable and is destroyed by light, so it wont spread that much.
Anatoxin-a is so toxic, that just 5 grams can kill 350 people. It got the alias "Very Fast Death Factor" because it can kill an animal or a human within a few minutes. If Anatoxin-a is injested, it causes paralyses by shutting down the communication between the brain and the muscles.
And this is precisely what makes this molecule so interesting. Our brain has million of synapses which connects the neurons. In each synapses there are neuron-transmitters which help the electrical signals to hop from one side of a synapses to the other. These signals must be shut off after having completed their purpose. To do so, our brain unleashes some sort of shut-down molecules which breaks the connection of the synapses and thus they terminate the signal. If one has the Alzheimer's disease, then these shut-off molecules do not operate normally and they shut-off more and more synapses in the bran.
It seems that Anatoxin-a may be able to shut of the shut-off molecules....