Age-related decline in sleep quality could be reversed

Researchers have suggested that age-related sleep decline can be prevented and might even be reversible.

To uncover basic age-related sleep mechanisms, the scientists at the Max Planck Institute (MPI) for Biology of Ageing in Cologne studied the fruit fly Drosophila melanogaster, a classical model organism in ageing research. "Drosophila's sleep has many features in common with that of humans, including the decline in quality", says Luke Tain of the MPI for Biology of Ageing.

Tain said that like humans, flies sleep at night and are active during the day. We can observe when and how long flies sleep, asserting that they can also determine their sleep quality by measuring how often they wake. This allowed them to study the effects of specific substances or other sleep-influencing factors such as age and genetic disposition.

Ageing researchers Athanasios Metaxakis, Luke Tain, and Sebastian Gronke, in the department of MPI Director Linda Partridge, discovered that a reduced activity in the IIS signalling pathway leads to improved sleep quality at night and higher activity levels at day.

Moreover, the scientists found out that day activity and night sleep are regulated by two distinct signalling pathways, night sleep being mediated through TOR and dopaminergic signalling. Surprisingly, if TOR's activity is acutely inhibited by treatment with the therapeutic agent Rapamycin, sleep quality improves even in old flies, suggesting that age-related sleep decline is not only preventable, but also reversible.

The new study has been published in the journal PLOS Biology.