Related Experiment Video
Updated: Jan 8, 2026
Light/dark Transition Test for Mice
Published on: November 13, 2006
Wild-Derived House Mice (Mus musculus) Are Able to Cope With a Constant Light Environment
Kevin Pham1,2, KayLene Y H Yamada1, Emma M Rhodes1,3
1Department of Biological Sciences, Auburn University, Auburn, Alabama, USA.
Abstract:
Exposure to altered nighttime lighting conditions has become common in today's modern world. Light at night disrupts circadian processes that govern feeding patterns, sleep/wake cycles, and metabolic homoeostasis, increasing the risk of developing pathologies associated with cardiometabolic disease. Yet, the underlying mechanism(s) responsible for mediating the resulting physiological outcomes are not clear. Mitochondrial function may provide valuable insight into the physiological costs associated with light at night, given that mitochondria contribute to variation in metabolic performance that underpin human diseases. In this study, 36 male and female wild-derived house mice (Mus musculus) were exposed to continuous light, darkness, or a control light cycle for 6 weeks. We examined animals' bioenergetic capacity at the whole-organism and subcellular level while also measuring changes in body condition and oxidative damage. We found that 6 weeks of constant light and darkness resulted in negligible changes in all our variables of interest. We did not detect strong mitochondrial responses in the liver or skeletal muscle of either sex exposed to constant light or darkness. Furthermore, we did not detect any difference in mitochondrial volume or lipid peroxidation in the liver between treatment groups. Lastly, there was no difference in body condition between treatment groups. Our data indicate that wild-derived mice are able to circumvent challenges of an altered light environment and escape physiological consequences.
Insights
Wild-derived mice exposed to constant light or darkness for six weeks showed no significant physiological changes. Their mitochondrial function and body condition remained unaffected, suggesting resilience to altered light environments.
Area of Science:
- Chronobiology
- Mitochondrial biology
- Metabolic health
Background:
- Altered nighttime lighting disrupts circadian rhythms, impacting feeding, sleep, and metabolism.
- This disruption increases the risk of cardiometabolic diseases, but underlying mechanisms are unclear.
- Mitochondrial function is crucial for metabolic performance and may reveal physiological costs of light at night.
Purpose of the Study:
- To investigate the physiological effects of altered light environments on wild-derived mice.
- To examine changes in bioenergetic capacity, body condition, and oxidative damage.
- To assess mitochondrial responses in liver and skeletal muscle.
Main Methods:
- 36 wild-derived house mice (Mus musculus) were exposed to continuous light, darkness, or a control light cycle for 6 weeks.
- Whole-organism and subcellular bioenergetic capacity were measured.
- Body condition and oxidative damage markers were assessed.
Main Results:
- Six weeks of constant light or darkness caused negligible changes in bioenergetic capacity, body condition, and oxidative damage.
- No significant mitochondrial responses were observed in the liver or skeletal muscle of either sex.
- No differences in mitochondrial volume or lipid peroxidation in the liver were detected.
Conclusions:
- Wild-derived mice demonstrated resilience to altered light environments.
- Mice were able to circumvent challenges posed by constant light or darkness without apparent physiological consequences.
- Mitochondrial function and metabolic health were not significantly impacted by the tested light conditions.
