Meeting Abstract
The notion that reproduction has an effect on future performance and longevity is long-standing dogma in evolutionary biology, yet there is little understanding of the mechanisms that underlie this relationship. One variable that has emerged as a likely link between reproductive effort and longevity is oxidative stress. Specifically, it is has been proposed that reproduction increases oxidative stress and in turn, oxidative stress results in cumulating cellular damage that impacts an individual’s longevity. Support for this hypothesis has been limited. We propose that there is limited support because ROS (reactive oxygen species), the molecules implicated in oxidative damage, are not consistently harmful. Instead, cells display a hormetic response to ROS exposure. For this presentation, the results of multiple studies that characterize how the mitochondria respond to an induced oxidative event and to a reproduction event will be described. In addition, how ROS exposure prior to reproduction impacts reproductive performance and how prior reproduction impacts a female’s response to an induced oxidative event will also be presented. Cumulatively, these data suggest that, at least relatively early in an animal’s reproductive life, increased ROS exposure associated with reproduction is more likely to enhance than to hinder the performance of females. Based on this evidence, we will propose a new model for understanding the tradeoff between reproduction and longevity whereby the early benefits of reproduction act to maximize subsequent reproductive performance, but delayed consequences of prior oxidative damage could contribute to early senescence in animals with high reproductive output. We recommend that future studies be designed to test these interacting effects.
