Meeting Abstract
Our understanding of the physiological responses to stress of wild animals is often based on studies where data is collected over a short period of time. Although many fundamental insights have been gained from this approach, this design often ignores the fact that each individual has experienced a unique set of sequential events that may have altered its physiology. These carry-over effects may explain much of the variation in performance and fitness found among individuals in wild populations. Moderate activity, or exercise, is associated with a plethora of benefits at the cellular level including improved mitochondrial function. For this study, we asked if the beneficial effects of exercise on mitochondria carry over to reproduction, improving the impact that reproduction has on mitochondrial capacity and function. We used the outbred IRC mouse as a model. Half of the mice were given access to a running wheel and half were not. The impact of running on mitochondrial function was then quantified after 1 month in half of the animals, with equal numbers collected from each group. The remaining animals were then bred so that the impact of running prior to breeding could be quantified. Relative to mice that did not have access to a running wheel, mice that ran demonstrated significantly higher total leg muscle mass (p < 0.05), a trend toward lower leg muscle ROS production (p = 0.07) and significantly greater respiratory function (p < 0.05). These results support prior findings that suggest exercise improves mitochondrial performance and thus, provides an exciting framework for our ultimate prediction that the positive mitochondrial effects of exercise will persist following a future reproductive event. These findings will be presented.
