748C Poster - 12. Physiology, metabolism and aging
Saturday April 09, 1:30 PM - 3:30 PM
Investigating Flock House virus-mediated changes in bioenergetics in aged Drosophila melanogaster
Authors: Dean Bunnell 1; Eli Hagedorn 1; Beate Henschel 2; Daniel L. Smith 3; Stephanie Dickinson 2; Andrew W. Brown 2; Maria De Luca 3; Ashley Turner 4; Stanislava Chtarbanova 1
Affiliations: 1) University of Alabama; 2) Indiana University; 3) University of Alabama at Birmingham; 4) Jacksonville State University
Keywords: b. metabolism; k. host/pathogen interactions
We have previously shown that Flock House Virus (FHV) kills older flies more rapidly than young adults without higher virus titers. This indicates that survival to FHV infection depends on tolerance mechanisms, which are not well characterized. FHV triggers profound transcriptomic changes in older Drosophila at time points before significant mortality is observed in young and aged cohorts. The age-dependent impairment of disease tolerance to FHV in Drosophila is characterized by stronger regulation of genes whose products function in mitochondria and mitochondrial respiration. We hypothesized that the Drosophila bioenergetic profile will be deregulated following FHV infection. The first 3 days of infection, we performed whole-organism respirometry of 5- and 30-days old individual Drosophila receiving non-injected, Tris-injected (control) or FHV-injected treatments to determine if metabolism plays a role in infection outcomes. Pairwise comparisons were conducted on the Least Squares Mean Oxygen Consumption Rate (OCR) to detect statistically significant differences between treatment groups. Our results show that FHV infection significantly reduces OCR compared to non-injected (p=0.0264) and Tris-injected (p=0.0164) controls. Although the factor of "Age" and the interaction of "Age x Treatment" did not have a significant effect on OCR, the interaction of "Age x Time Post-Treatment" shows a significant change in OCR in aged flies compared to young individuals at 24-hours. The OCR signature at 24-hours varied in response to both treatment and an individual’s survival status at 48-hours. FHV-injected flies that died prior to 48-hour measurements had a significantly lower OCR (p=0.0438) compared to flies that were alive at 48-hours.