0351 Biological Validation of Lifespan Modeling in Drosophila Melanogaster

Abstract Introduction Sleep is an evolutionary conserved function across species, indicating that it is a necessary function for life. Inadequate sleep promotes several disease states across a variety of systems that reduce lifespan, leading us to hypothesize that there must be a general underlying mechanism affected by sleep. To discover this mechanism, our interdisciplinary team has developed unique mathematical models to predict lifespan in chronologically identical Drosophila melanogaster, based on their sleep characteristics. Proteostasis(definition), oxidative stress, and energy homeostasis are all associated with aging and thus make sense to pursue first in lifespan model validation. Methods Sleep is monitored for 30-days using the Trikinetics DAM system. Those data are used to make lifespan predictions, and flies are then binned into two groups – predicted long life (PLL) and predicted short life (PSL) for subsequent experimentation. To validate the models, we used a variety of molecular techniques. Overall soluble protein was quantified using a standard Bradford assay protocol. Metabolites were quantified using standard LC-MS/MS methods. MALDI-TOF imaging was used to examine energy metabolism, oxidative stress, and lipids. MALDI-TOF imaging was done using 9-Aminoacridine (9-AA) matrix with a target range between 50 m/z -1000 m/z. All statistical analyses were done using a Student’s T-test, with α=0.05. Results Our predictions successfully binned the flies into two groups, with 26.7% of PSL flies dying between lifespan prediction and experimentation, compared to only 11.8% of PLL flies. We found evidence of proteome collapse, with overall soluble protein concentration significantly higher in PLL flies than PSL flies (p< 0.05). Our PSL flies had a significantly higher GSSG/GSH ratio, indicating oxidative stress (p< 0.0001). Furthermore, we found elevated AMP in PSL flies, indicating trouble maintaining the energy required for proteostasis and appropriate oxidative stress response. MALDI imaging showed localization differences of AMP/ATP/ADP and GSSG/GSH in abdomens of PLL and PSL flies (p< 0.05). Furthermore, MALDI-TOF imaging found free fatty acids and acylcarnitines to be significantly decreased in PSL flies (p< 0.05). Conclusion Our models can successfully separate our flies into distinct, biologically different groups, based on sleep characteristics. This allows us to make inferences between sleep and molecular function. Support (if any)