Sex Differences in the Effect of Dietary Restriction on Life Span and Mortality Rates in Female and Male Drosophila Melanogaster

Abstract

Dietary restriction (DR) has been shown to increase life span in taxonomically diverse animal species. In this study we tested for sex differences in the response of life span to graded severity of DR in Drosophila melanogaster. In both sexes, life span peaked at an intermediate food concentration and declined on either side. However, the magnitude of the response and the food concentration that minimized adult mortality differed significantly between the sexes. Female life span peaked at a food concentration 60% of the standard laboratory diet compared to a concentration of 40% for males. Moreover, female flies subject to DR lived up to 60% longer than did starved or fully fed females, whereas males subjected to DR lived only up to 30% longer. Analysis of age-specific mortality rates showed that DR extended life span by decreasing baseline mortality rates in both sexes, and to a greater extent in females. The differences in the response to DR in female and male Drosophila may be due to previously documented sex differences in sensitivity of life span to insulin/insulin-like growth factor-1 signalling or in nutrient/energy demand and allocation/utilization.

Lifespan modification by glucose and methionine in Drosophila melanogaster fed a chemically defined diet

“…Demographic modeling has suggested that dietary restriction in Drosophila acts by lowering age independent mortality rather than by slowing the accumulation of senescent damage (Mair et al 2003;Magwere et al 2004;Partridge et al 2005). In the present study, we did not observe such an effect.…”

“…This observed longevity is particularly impressive because non-virgin females of the present study would be expected to have shorter lifespans than those reported previously for virgin females, due to the cost of reproduction (Chapman et al 1998). The full impact of these defined media on longevity in relation to fecundity in both female and males remains to be explored (Good and Tatar 2001;Magwere et al 2004).…”

“…We studied longevity in non-virgin female flies because of known sex-related influences on lifespan in Drosophila (Magwere et al 2004). Cohorts were established by allowing flies of the same ages to mate at a density of 10 males and 20 females per bottle.…”

Comparative transcriptomics across 14 Drosophila species reveals signatures of longevity

“…Under laboratory settings, the lifespan of D. melanogaster has been successfully increased by genetic manipulations (Clancy et al., 2001; Hwangbo, Gershman, Tu, Palmer & Tatar, 2004; Kapahi et al., 2004; Lin, Seroude & Benzer, 1998; Orr & Sohal, 1994; Parkes et al., 1998; Sun, Folk, Bradley & Tower, 2002; Tatar et al., 2001), dietary interventions (Chapman & Partridge, 1996; Grandison, Piper & Partridge, 2009; Lee et al., 2014; Magwere, Chapman & Partridge, 2004; Mair, Goymer, Pletcher & Partridge, 2003; Min & Tatar, 2006), and pharmacological treatments (Bjedov et al., 2010; Danilov et al., 2013; Wang et al., 2013). These findings are similar to those reported in other model organisms and highlight the important role of nutrient sensing, mTOR, NAD/sirtuins, insulin/IGF1 signaling pathways, and other systems in lifespan control (Fontana, Partridge & Longo, 2010; He et al., 2014).…”

Chemical changes in aging Drosophila melanogaster

“…Cohorts of female flies were selected for investigation, since DR has a much more substantial effect on lifespan in females than in males (Magwere et al 2004). An initial, control cohort (25/2SY) was cultured under normal conditions (25°C and 2SY food), to generate samples to optimise analytical methods and survey the chemical changes occurring during normal aging in D. melanogaster.…”