Intranasal administration of insulin lowers amyloid-beta levels in rat model of diabetes.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by abnormal accumulation of amyloid beta (A beta) peptide in brain regions subserving memory and other cognitive functions. Hyperglycemia and perturbed insulin signaling have been proposed as pathogenic factors contributing to AD. The aim of the present study is to validate the use of streptozotocin (STZ) injected rats as an experimental model of AD. Using this model, the effect of intranasal administration of insulin on reduction of A beta levels was measured. The current findings strengthen the case for insulin as therapy for AD afflicted individuals with or without diabetes.