Effects of 20-Hydroxyecdysone and Calcium Supplemented Prednisone on the Body Length of Fruit Flies

Overview

Due to asthma, I took prednisone, an oral corticosteroid that reduces inflammation in the airways. During my 7th grade physical, my doctor noticed my growth rate had decreased from the 50th percentile to the 20th percentile. My doctor mentioned this could be due to the prednisone treatments I had been prescribed. Wondering if this could be shown in an animal model, the fruit fly (Drosophila melanogaster) was selected because of quick generation time and the ease of mixing the medication in question with their food. In my previous experiments, data clearly showed a decrease in the body length of Drosophila as the prednisone dosage was increased. In an attempt to better understand why the body length was decreasing, two additional experiments were carried out in this study: a) the food was supplemented with calcium to see if calcium could counteract the effect of the prednisone and b) determine if prednisone was acting similar to the molting hormone, ecdysone, which has a similar chemical structure to prednisone. Research suggested that 20-hydroxyecdysone, a muscle supplement sold in health stores, might produce similar effects so it was also included in the study as it was a low-cost chemical to purchase. It was hypothesized that if prednisone was causing an ecdysone-like effect on molting, then the body length of Drosophila exposed to ecdysone and prednisone would show no statistical difference in length when compared to each other. ANOVA and Scheffe tests showed no significant differences (P > 0.05) between calcium with prednisone and the control, suggesting that the calcium had no significant effect on Drosophila body length. ANOVA and Scheffe test did not show a significant decrease (P > 0.05) in body length of Drosophila exposed to 20-hydroxyecdysone compared with the control group, suggesting this supplement had no significant effect on body length. ANOVA and Scheffe tests did show a significant decrease (P < 0.05) in body length for Drosophila exposed to ecdysone and prednisone treatments compared to the control group, but showed no significant difference (P > 0.05) to each other. These data suggest that prednisone may be having an effect on the molting process of the Drosophila leading to the reduced body length. More research is needed to understand how this finding may be related to a reduction in the growth rate observed in me and other pediatric patients prescribed prednisone.