In 2005, while testing the effects of impaired insulin signaling on the brain, Suzanne de la Monte at Brown University and her colleagues observed several unexpected phenomena in her experimental mice. Hallmarks of neurodegenerative disease had surfaced: oxidative stress, amyloid fibrils, and cell loss. "It was the craziest thing," de la Monte says. Glucose metabolism and Alzheimer's had been linked previously, says de la Monte, and perhaps her findings explained why.
Looking in the brains of patients diagnosed with Alzheimer's disease, de la Monte found reductions in insulin, insulin-like growth factor, and downstream elements such as tau, insulin receptor substrate, and kinases.1 Type 1 diabetes is a deficiency in insulin production, and type 2 is a resistance to insulin, where there is plenty of insulin but cells don't respond to it. Her group coined the term "type 3 diabetes" to explain their observations. "In Alzheimer's you have both things going ...
