A new study suggests that insulin resistance is an important factor in cognitive decline associated with Alzheimer’s disease.
Insulin activity involved
The researchers of the Perelman School of Medicine identified abnormalities in insulin and IGF-1 (Insulin-like Growth Factor) activities in people without diabetes but with Alzheimer’s disease.
Insulin is a hormone that not only modulates glucose intake, but also promotes brain cell health, growth, survival, and function. Insulin resistance would therefore be a major contributor to the cognitive decline associated with Alzheimer’s disease.
Experts estimate that the risk of developing Alzheimer’s disease increases by 50% with Type 2 diabetics. Type 2 diabetes is precisely due to insulin resistance and accounts for 90% of all diabetes.
Insulin resistance, a scourge for the brain
Type 2 Diabetes as well as the first stage of diabetes (Type 1) is characterized by hyperglycemia: high blood sugar levels.
Investigators studied extracts of brain tissue from non-diabetic people who had died of Alzheimer’s disease, stimulating the tissue with insulin and measuring the rates of change.
What was concluded: There was less insulin activation in decedents from Alzheimer’s disease than in decedents whose death was not from brain disease. Other proteins related to insulin action in the brain were also abnormal in Alzheimer’s disease deaths. The researchers therefore determined that insulin resistance is another factor in cognitive decline.
Source: University of Pennsylvania