Diabetes drugs hold potential for treatment of Alzheimer's disease

A disease mechanism linking Alzheimer's disease and Type 2 diabetes has been discovered by Fernanda De Felice, a professor at Federal University of Rio de Janeiro, Brazil. This discovery can lead the way to new therapies to preserve brain health. The results of the study were presented at the 2018 Canadian Neuroscience Meeting, in Vancouver, Canada.

The mechanism, which consists of a pathway leading to inflammation in different parts of the brain, leads to memory impairments, degeneration of connection between neurons (synapses) and glucose intolerance.

Alzheimer's disease is a complex disorder. Researchers and health professionals are recognizing more and more that Alzheimer's disease affects more than just memory, as it also affects appetite, sleep, and mood (often leading to depression). Compelling evidence indicates that brain regions not classically linked to memory are affected by this disease.

Prevalence of both Alzheimer's's disease and type 2 diabetes is increasing worldwide. Studies have shown that type 2 diabetes is a risk factor for Alzheimer's disease, and vice-versa. Dr. De Felice and her team have therefore searched for common factors that could throw some light on co-occurrence of the two diseases.

Her research on models of Alzheimer's disease, both in mice and non-human primates, has led to the identification of a pathway that causes inflammation in the brain, and that affects insulin signaling and endoplasmic reticulum stress. Reduction in insulin or insulin signaling is responsible for the increased blood glucose levels seen in diabetes, while endoplasmic reticulum stress is a measure of cell damage, and can lead to cell death.

"We know that the Alzheimer brain responds less to insulin, which is also indicative of some form of cross-talk in the pathways of these diseases. By looking at non memory-related symptoms of Alzheimer's disease we are getting a better understanding of the complex nature of this disease and of the different pathways it affects " says Dr. De Felice.

The molecular and cellular links between AD and diabetes suggests novel therapeutic strategies based on anti-diabetic agents. In previous work, Dr. De Felice's team had tested such a strategy, with the diabetes drug liraglutide. The drug could help in the reversal of cognitive impairment, changes in insulin sensitivity and restore synapses in non-human primate models of Alzheimer's disease, showed her studies.

"A better understanding of the pathway involved in the development of the complex symptoms of Alzheimer's disease will be key to identifying more therapeutic targets to treat this devastating disease, and preserve brain health" says De Felice.