Mapping sex differences in the effects of protein and carbohydrates on lifespan and reproduction in Drosophila melanogaster: is measuring nutrient intake essential?

Abstract

Understanding how diet affects reproduction and survival is a central aim in evolutionary biology. Although this relationship is likely to differ between the sexes, we lack data relating diet to male reproductive traits. One exception to this general pattern is Drosophila melanogaster, where male dietary intake was quantified using the CApillary FEeder (CAFE) method. However, CAFE feeding reduces D. melanogaster survival and reproduction, so may distort diet-fitness outcomes. Here, we use the Geometric Framework of Nutrition to create nutrient landscapes that map sex-specific relationships between protein, carbohydrate, lifespan and reproduction in D. melanogaster. Rather than creating landscapes with consumption data, we map traits onto the nutrient composition of forty agar-based diets, generating broad coverage of nutrient space. We find that male and female lifespan was maximised on low protein, high carbohydrate blends (~ 1P:15.9C). This nutrient ratio also maximised male reproductive rates, but females required more protein to maximise daily fecundity (1P:1.22C). These results are consistent with CAFE assay outcomes. However, the approach employed here improved female fitness relative to CAFE assays, while effects of agar versus CAFE feeding on male fitness traits depended on the nutrient composition of experimental diets. We suggest that informative nutrient landscapes can be made without measuring individual nutrient intake and that in many cases, this may be preferable to using the CAFE approach. The most appropriate method will depend on the question and species being studied, but the approach adopted here has the advantage of creating nutritional landscapes when dietary intake is hard to quantify.

The effect of lactational low protein diet on skeletal muscle during adulthood and ageing in male and female mouse offspring

“…None of these studies had an NLL group in their studies. However, Carey et al, (2022), negatively correlated protein intake with the lifespan of male and female Drosophila melanogaster which contradicts with this study.…”

Age‐related flexibility of energetic metabolism in the honey bee Apis mellifera

“…Moreover, Pirk et al 95 determined that low protein to carbohydrates diet prolonged workers lifespan and that strict carbohydrate diet extended it even more. Indeed, it is now well known that, except for some species, 96 low protein: carbohydrate ratio enhances longevity at the expense of reproduction 97–103 . However, eusocial insects challenge this assumption and exhibit on the contrary an extended lifespan in reproductive females which concomitantly consume high amounts of proteins 104 .…”

Drosophila suzukii energetic pathways are differently modulated by nutritional geometry in males and females

“…The SWD host fruit-based diets tested in the present study, namely, blackberry, raspberry, blueberry, strawberry, and grape, have differences in total protein and sugar content, with raspberry having the highest P:S ratio (and the lowest TSS levels) and grape having the lowest P:S ratio. Dietary proteins are known to stimulate and regulate Drosophila reproduction in both females (oogenesis and vitellogenesis) and males (sperm production) 5,[38][39][40][41] while carbohydrates are an essential source for glycogen synthesis and fat storage 32,42 . Previous studies already pointed to raspberry as being the most suitable host for SWD in terms of preference and best reproductive performance 13 , suggesting that SWD has a preference for high P:S fruits.…”