Fighting Alzheimer's Disease and Type 2 Diabetes: Pathological links and Treatment Strategies

The incidence of Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) with associated serious complications continues to grow rapidly especially in developed countries. Emerging evidence indicates that AD and T2DM share some common risk factors with comparable pathological features including insulin resistance, amyloidogenesis, glucocorticoid imbalance, inflammation, mitochondrial function and oxidative stress. T2DM has been identified as a risk factor for AD. It has even been hypothesized that AD might be "type 3 diabetes". In addition to amyloid precursor protein processing and tau phosphorylation, commonalities between T2DM and AD in molecular mechanisms provide clues to the identification of novel therapeutic targets such as glucagon-like peptide 1, butyrylcholinesterase, and receptor for advanced glycosylation end products. Although several classes of anti-diabetic drugs are available, achieving long-term glycaemic control without side effects is often challenging. This review summarizes recent evidence for the pathological links, common therapeutic targets, currently the U.S. Food and Drug Administration approved and potential future therapies, giving special attention to ongoing clinical trials of antidiabetic drugs in AD patients and common therapeutic strategies in the management of both AD and T2DM.