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

Department of Biology, University College London, Darwin Building, Gower Street, London WC1E 6BT, United Kingdom.
The Journals of Gerontology Series A Biological Sciences and Medical Sciences (Impact Factor: 5.42). 02/2004; 59(1):3-9. DOI: 10.1093/gerona/59.1.B3
Source: PubMed


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.

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    • "Reproductive activity generally decreases survival in both sexes (e.g. courtship behaviour in males, egg production and the related high nutritional intake and metabolism in females: Soliman & Van Herrewege, 1988; Cordts & Partridge, 1996; Magwere et al., 2004). However, reproduction is rarely taken into account in previous studies of hsp functions. "
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    • "Although individuals of both sexes should respond to nutrient limitation in ways that maximize their lifetime fitness (Collins 1980), males and females have distinct nutritional requirements based on their divergent reproductive roles. To date, only a few studies have examined sex-specific responses to early food limitation (but see Karlsson et al. 1997; Clarebrough et al. 2000; Hunt et al. 2004; Gwynne 2004; Boggs and Freeman 2005; Magwere et al. 2004; Maklakov et al. 2008; Stillwell and Davidowitz 2010). Such sex-specific responses may be especially marked in organisms whose mating systems include nuptial gifts. "
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    • "The life span of male Drosophila was measured at 25oC. Females were excluded from the life span analysis due to observed sex differences regarding the effect of dietary restriction on lifespan [31]. Adult flies were collected 24-hours post eclosion and maintained in standard culture vials (25 mm x 95 mm) with a maximum of 10 flies per vial. "
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