EXERCISE AND DIET PROGRAMS DROSOPHILA SIMULANS OFFSPRING METABOLIC PHENOTYPE

Abstract

Obesity in pediatric patients has increased significantly in recent decades, along with susceptibility to Type 2 Diabetes (T2D), cardiovascular disease, cancer, and mortality. The relative contribution of genetic and environmental conditions is unclear in these cases. Drosophila simulans contain an insulin-like growth pathway (IGF-1), which is a large contributing factor in anabolic stimulation and growth in children. The fat body of Drosophila is the equivalent of the vertebrate adipose tissue and liver regarding its storage and major metabolic functions. Thus, Drosophila is an ideal model to study the effects of environmental conditions, namely exercise and diet, on obesity phenotype. The purpose of this experiment was to characterize the model of obesity in Drosophila and determine how much diet and exercise act as epigenetic factors that affect metabolic function of parents and reprogram offspring phenotype trans-generationally. F0 male flies were broken into four groups, control (CF), exercise (EF), western diet (WF), and western diet with exercise (WEF), and exposed for a week. The F0 flies were then evaluated for behavioral and physical changes through monitoring locomotor activity, sleep-wake cycle, food preference, weights, and mortality. A subsection of each group was bred after exposure rather than tested, and their F1 offspring, in some instances, were tested. This process was repeated for F2 and F3. Western diet resulted in greater mortality and reduced activity in F0 and F1 flies. Locomotor data also showed increased nighttime activity in F0 western diet flies, and WFO flies from F1 and F3, suggesting a heritable disruption to the circadian rhythm. Food preference data shows that Western diet food is preferred by F0 flies that are pre-exposed to it, while control diet is preferred by those who were not. Naive F1 male and female flies with exposed parents prefer Western diet, while offspring whose parents were fed by control diet prefer control diet. Our results indicate that obesity characteristics in Drosophila are comparable in many instances with that of humans, making them a good study model for obesity.