The effects of caffeine on the learning and memory of drosophila melanogaster at the early stages of mapttau expression

Alzheimer’s disease (AD) is the most frequently encountered form of dementia. Research in mammalian model systems and clinicalstudies in humans indicate that caffeine in the diet can decrease the frequency and severity of Alzheimer’s disease. The effects of caffeine on Alzheimer’s pathology in the more basic model organism, Drosophila melanogaster, have not been extensively studied. We evaluated the effects of caffeine in the diet of Drosophila expressing the early stages ofa pathology common in Alzheimer’s, tau pathology. We measured and compared the effects of the neuropathology by characterizing deficits in learning and memory in Drosophila expressing human tau that were fed caffeine versus those that were not. We also tested the longevity of the flies expressing tau pathology that were exposed to caffeine versus none. To assess behavioral decline,a spatial behavioral assay was used to quantify deficits in spatial learning memory. It was found that Tau flies lived longer than even wild type, UAS and Gal-4 line controls. Tau flies not exposed to caffeine also lived longer than Tau flies exposed to caffeine. The preliminary spatial memory data indicates that caffeine exposure could aid in short-term memory formation. This work could support the use of Drosophila as a high-through put system to study behavior and the underlying neural deficits associated with AD.