GLUCOSE REGULATION AND COGNITIVE FUNCTIONS - RELATION TO ALZHEIMERS-DISEASE AND DIABETES

Glucose has been found to improve memory in animals and humans. Animal research has revealed that glucose may improve memory through a facil itation of acetylcholine (ACh) synthesis and release in the brain. Thi s glucose-related memory improvement has prompted research in elderly humans. These studies have shown that the memory-improving action of g lucose depends on each individuals' blood glucose regulation. Based on these data, researchers have evaluated the effect of glucose on memor y in patients with Alzheimer's disease (AD). Results demonstrated that glucose could improve memory in a subset of patients that had abnorma lities in their blood glucose regulation. Interestingly, these alterat ions in blood glucose regulation were believed to depend on the severi ty of the disease process. Another line of investigation has focused o n alterations in brain glucose metabolism. Both animal models and stud ies with Type II diabetic elderly patients have shown that altered glu cose regulation impairs learning and memory processes. It is possible that in AD patients, hyperglycemia exerts a deleterious effect by pote ntiating the neuronal death produced by other pathological processes t aking place such as amyloid deposition. Based on these data, it appear s important to find the prevalence of altered glucoregulation at vario us stages of AD. Secondly, it may be of interest to determine prospect ively whether altered glucoregulation is linked to a faster progressio n of the disease. Finally, if such a relationship is observed, the nex t logical step would be to determine whether AD patients could benefit from treatments aimed at normalizing blood glucose regulation and imp roving insulin sensitivity.