Effect of amyloid beta on nutrient uptake and ATP in the brain cells

Unintentional weight loss in older adults often precedes Alzheimer’s disease (AD). Positron emission tomography (PET) scan reveals that AD patients exhibit reduced uptake of fluorodeoxyglucose into brain cells, defined as ‘hypometabolism’. However, cellular mechanisms underlying weight loss and hypometabolism have not received much attention. The primary goal of the study was to test the hypothesis that cells become starved in confrontation with amyloid beta proteins (Aβ), which are increasingly aggregated in the AD brain. Cellular ATP is known as a biomarker indicating for cell starvation. We found that Aβ caused a dose-dependent reduction in ATP of astrocytes. This effect was similar to those of cells being deprived from nutrients (i.e., glucose, pyruvate and glutamine). Together, the data of the present study support the hypothesis that cell starvation is likely associated with weight loss and hypometabolism in AD patients.