Scientists have found that a housekeeping biological mechanism in the brain may also regulate sleep. Researchers from the University of Pennsylvania found a specific signaling pathway in fruit flies and zebrafish is required for sleep. This pathway is also important in getting rid of buildup of abnormal protein aggregates in brain cells. The researchers’ findings were published in the journal Current Biology.
PERK Signaling Pathway
This biological mechanism is called the PERK signaling pathway. Its role is to remove buildup of unwanted protein aggregates in brain cells. When these protein aggregates build up, PERK signaling will cause cells to temporarily stop their assembly of most proteins. This process is called proteostasis, an important biological process.
The researchers blocked the PERK signaling in Drosophila fruit flies and zebrafish. This resulted in the fruit flies and zebrafish sleeping less than normal. In addition, when the researchers stimulated PERK in fruit flies causing over-production of PERK, the flies slept more. Since PERK signaling is present in two such diverse animals as fruit flies and zebrafish, it may also be present and operate in the same role in humans.
Link to Neurodegenerative Diseases
Scientists have postulated that sleep loss and sleep disorders are linked somehow to neurodegenerative diseases such as Alzheimer’s and Parkinson’s. If the PERK signaling pathway works in a similar fashion, then understanding this mechanism may help to devise new strategies against both sleep disorders and neurodegenerative diseases.
This is the first time a link has been discovered between proteostasis and sleep. The findings also indicate that wakefulness increases protein-aggregate accumulation in brain cells, leading to more PERK signaling. In other words, being awake causes protein-aggregate to accumulate in the brain. This accumulation activates PERK signaling, leading to sleep when these protein-aggregate can be cleaned up.
The researchers believe that more research into the connection between the process of proteostasis and sleep may lead to therapies for helping improving sleep quality and reducing the risk of neurodegenerative diseases.