Investigation of the interaction between oxidative stress and ethanol in a Drosophila model

Reactive oxygen species (ROS) are unstable oxygen-containing molecules that oxidize most cellular macromolecules. Because ROS occur as a natural result of cellular metabolism, they are experienced by all aerobically respiring organisms. Ethanol is known to increase the production of reactive oxygen species (ROS) in a variety of ways, leading to oxidative stress. Drosophila melanogaster exposed to ethanol during development have decreased survival and a significant developmental delay. Our lab has unpublished data indicating that oxidative stress can phenocopy the effects of ethanol exposure. We hypothesize that at least some of ethanol’s toxic effects are due to oxidative stress. One way to test this hypothesis is to test ethanol and peroxide for synergistic effects on fly development. We will rear flies on a combination of ethanol and hydrogen peroxide, with each chemical at a sublethal concentration. If the delay and lethality caused by ethanol is due to oxidative stress, we expect this combination to have a non-additive effect on survival and development time. Preliminary data show that flies reared on this combination show a developmental delay, as predicted. However, synergistic effects were not observed in survival. The survival rate in flies was higher than expected, which might indicate that ethanol-induced lethality is not due to oxidative stress. For future work, we are using immunoblotting and qPCR to examine ethanol-reared flies for markers of oxidative stress.