Will insulin help with Alzheimer's disease?

Scientists at Northwestern University of Chicago and the Brazilian University of Rio de Janeiro have found a link between two common senile ailments - type 2 diabetes and Alzheimer's disease.

Amyloid plaques, which are known as the main sign of Alzheimer's disease, are dangerous not so much by themselves as due to the proteins ADDL (Aß-derived diffusible ligands, soluble oligomers of beta-amyloid), which specifically bind to insulin receptors on the surface of synapses. As a result, local oxidative stress develops, disrupting the interaction between neurons with obvious consequences in the form of deterioration of cognitive abilities and memory and, ultimately, death.

In experiments on the culture of hippocampal neurons – a common model for studying the effect of various drugs on brain cells – the researchers showed that the addition of insulin to the culture medium prevented the binding of ADDL to insulin receptors. The protective effect of insulin was enhanced by the addition of rosiglitazone (rosiglitazone), a drug that lowers blood glucose levels and is used to treat type 2 diabetes.

The picture shows a combined image of two neurons. Synapses joined by ADDL globules glow red, and normally functioning synapses glow green.

The neuron, half of which is shown on the right side of the image, is protected from the action of harmful proteins by the addition of insulin – ADDL almost does not bind to insulin receptors on its surface.

The leader of the work, William L. Klein, professor of neurobiology and physiology at Northwestern University, suggests that age-related decrease in insulin sensitivity increases the risk of Alzheimer's disease, and the action of insulin can protect neurons from this danger.

According to his colleague, Professor Sergio Ferreira from Rio de Janeiro, the knowledge that Alzheimer's disease is a kind of diabetes of the brain may someday lead to the development of fundamentally new methods of treatment for this serious disease.

Article by Fernanda G. De Felice et al. Protection of synapses against Alzheimer's-linked toxins: Insulin signaling prevents the pathogenic binding of Aß oligomers is published in open access in the electronic version of PNAS

Portal "Eternal youth" http://www.vechnayamolodost.ru according to Northwestern University: Insulin is a Possible New Treatment for Alzheimer's

04.02.2009