RESUMO
Mistiming of circadian rhythms impairs quality of life. The sleep fragmentation that results can lead to fatigue, mood alteration, and short-term memory problems. Unfortunately, this suite occurs in humans as we age. In the current study, we used high-resolution monitors to track how circadian patterns of locomotor activity change in female Drosophila ananassae as they enter mid-to-late life. This equipment is a more recent addition to the fly circadian field and has not been previously used for long-term activity tracking. At 2-3â¯days post-eclosion, D. ananassae were placed into climate-controlled vivariums for 60â¯days. Daily actograms were generated for each animal, along with a time series of activity across the observational period. Consistent with findings from older rodents and humans, older D. ananassae exhibited degraded patterns of wake and sleep that were fragmented-but still rhythmic-across the 24-h cycle. Overall levels of daily activity declined with age, with particular loss of circadian arousal in the wake-maintenance zone a few hours before bedtime. Interestingly, our high-resolution monitoring strategy was also able to document a sleep correlation previously associated with human aging in flies: displacement of sleep timing arising from possible changes in circadian and homeostatic regulation. Future experiments may determine whether the age-related impairments seen in the sleep-circadian system of D. ananassae can be mitigated through precision light treatment.
