Meeting Abstract

P1.19  Monday, Jan. 4  Mild life extension and reduced reproductive output in female flesh flies on dietary protein restriction BASTEA, L*; WALKER, L; VIRGILIO, A; BRIX, KV; WADA, RH; WESSELS, F; HAHN, DA; HATLE, JD; Univ. of North Florida; Univ. of North Florida; Univ. of North Florida; Univ. of Miami FL; Univ. of North Florida; Univ. of Florida; Univ. of Florida; Univ. of North Florida jhatle@unf.edu

Dietary restriction (DR) extends lifespan in most organisms, usually while reducing reproduction. Fruit flies are widely used for aging research and eat yeast to obtain both protein and carbohydrate. In contrast, lab flesh flies obtain protein and carbohydrate separately, from liver and sugar respectively. Hence, flesh flies may be useful to distinguish between the roles of these two nutrients in DR. We tested various frequencies of protein availability on lifespan in flesh flies offered continuous sugar. Liver every 2nd, 3rd, 4th, or 5th day all significantly extended lifespan (Kaplan-Meier test; all P < 0.05), but the increase in median life span for these treatments was only 10.7±3.5% over controls (fed liver continuously). Further, the percentages of life extension (median survival of DR cages / median survival of control cages) had 95% Confidence Intervals that overlapped zero, with one exception; flies on every 2nd day liver had weak but significant life extension (95% CI = 22.6-0.6%). Offering liver less frequently (i.e., every 6th, 9th, or 12th day) resulted in mass mortality after feeding, which likely was not due to senescence. Flies that were offered only sugar had moderate life extension (95% CI = 29.8-9.4%). In comparison, life extension in fruit flies on DR is ~50%. Similar to the mild life extension upon liver restriction, lifetime fecundity (73% of controls; P < 0.0001) and oocyte growth (P = 0.009 at day 5) were slightly but significantly reduced. In contrast to liver restriction, offering sugar every other day (but constant liver) reduced life span 30%. These data suggest that restriction of dietary protein can reduce reproduction and perhaps extend lifespan in flesh flies, but only slightly.