Reproduction alters oxidative status when it is traded-off against longevity

Abstract

Oxidative stress has been proposed to mediate one of the most important aspects of life-history evolution: the trade-off between reproduction and self-maintenance. However, empirical studies have cast doubt on the generality of this intriguing notion. Here, we hypothesize that reproduction alters oxidative status only when a trade-off between reproduction and self-maintenance occurs. Accordingly, in female Bicyclus anynana butterflies, we found that reproduction affected oxidative markers only under challenging thermal conditions that made the trade-off between reproduction and longevity emerge. Interestingly, under such conditions, butterflies favored longevity over reproduction, suggesting that self-maintenance mechanisms were activated. Accordingly, butterflies reproducing under challenging thermal conditions exhibited enhanced antioxidant defenses and stable oxidative damage. Altogether, our results indicate that a trade-off between reproduction and self-maintenance is indeed a necessary condition for reproduction to alter oxidative status, and that the effects of such a trade-off on oxidative status depend on whether priority is given to self-maintenance or reproduction. Assessing the existence of the trade-off between self-maintenance and reproduction, and whether self-maintenance is prioritized relative to reproduction is therefore crucial for understanding variation in oxidative status in reproducing animals, which may clarify the general implication of oxidative stress in the resolution of life-history trade-offs.

Overproduction of superoxide dismutase and catalase confers cassava resistance to Tetranychus cinnabarinus

“…Moreover, a trade-off was observed between self-maintenance and reproduction in animals. The effects of such a trade-off on the oxidative status depend on whether priority is given to self-maintenance or reproduction33. Accordingly, the development and reproduction of T. cinnabarinus feeding on the transgenic cassava lines were significantly inhibited in this study (Figs 5 and 6).…”

Feeding on ripening and over-ripening fruit: interactions between sugar, ethanol and polyphenol contents in a tropical butterfly

“…We then measured ADH activity and the oxidative status of butterflies by following protocols described in Fischer et al (2014) and Beaulieu et al (2015). Briefly, the frozen body (thorax and abdomen) of each butterfly was crushed in 200 μl of phosphatebuffered saline (100 mmol l −1 , pH 7.4) with one tungsten carbide bead (3 mm) at high speed shaking (30 times s −1 , 1 min).…”

Sexual signals reveal males’ oxidative stress defences: Testing this hypothesis in an invertebrate

“…Studies on vertebrates have examined the relationship between SSC and the levels of ROS and antioxidant production, as well as damage to biomolecules (Metcalfe & Monaghan, ; Monaghan, Metcalfe, & Torres, ; Sharick, Vazquez‐Medina, Ortiz, & Crocker, ). With regard to invertebrates, however, studies of oxidative stress have considered traits such as predation (Janssens & Stoks, ), reproduction (Rey, Pélisson, Bel‐Venner, Voituron, & Venner, ) and sexual dimorphism in life span and ageing (Archer, Sakaluk, Selman, Royle, & Hunt, ; Beaulieu, Geiger, Reim, Zielke, & Fischer, ). The authors of a key paper found that younger males of the cricket Gryllodes sigillatus had more total antioxidant capacity (TAC) than older males and suggested that calling effort may increase pro‐oxidants, favouring a decrease in oxidative stress defences (Archer et al., ).…”