If you have experienced American society in any way, especially American english class society, you have probably heard the aspirational narrative of the American Dream. That fantastical idea that anybody, no matter where you come from and who you are, anything is possible if you just work hard enough to get there. This can be a very motivational thought, however it has also led to the toxic work obsessed and sleep deprived culture that we have developed in the United States today. The 40 hour work week minimum that constitute our full time career jobs, the 8am school starts that begin as young as 6 years old, in combination with the constant overstimulation from technology that keeps us up later at night than our normal circadian rhythm would allow, all of these practices are leading to a massive accumulation of sleep debt starting at a very young age.
Alzheimer’s disease has been linked to increased amounts of the beta-amyloid peptides as well as accumulations and aggregations of the tau protein in the brain (Lucey et al., 2019). In a normal day, tau proteins aggregate in healthy human brains and are then cleared away while sleeping so that day to day aggregations are not adding up (Collins, 2019). Studies have shown that decreased amounts of non rapid eye movement sleep (NREM) lead to increases in beta-amyloid depositions (Lucey et al., 2019) which is an early signal of Alzheimer’s and chronic lack of sleep correlates to increased tau protein tangles which indicates disease progression and decline in cognition (Collins, 2019). Generally, tau protein levels increase during waking hours and decline when humans are sleeping. A study performed by Holtzman concluded that when adult humans did not sleep for an entire night, there was a 30% increase in beta-amyloid in the individuals CSF along with tau protein levels increasing by about 50% (Collins, 2019). In studies of chronic sleep deprivation done on mice it was shown that less sleep increased the amount of tau protein found in the animals brains and that the tangles that appeared over time were in the same locations as those found in people with Alzheimer’s disease (Collins, 2019).
It may not be possible to get enough sleep every single night but it is worth consciously making a decision to try to do so as often as possible. The studies linking Alzheimer’s to sleep deprivation are very new and more research is being conducted but in the meantime, getting more sleep certainly isn’t going to hurt.
Collins, F. (2019). Sleep loss encourages spread of toxic Alzheimer’s protein. NIH Director’s Blog. Available from: https://directorsblog.nih.gov/2019/02/05/sleep-loss-encourages-spread-of-toxic-alzheimers-protein/
Lucey, B. P., McCullough, A., Landsness, E. C., et al. (2019). Reduced non-rapid eye movement sleep is associated with tau pathology in early Alzheimer’s disease. Science Translational Medicine, 11(474). doi: 10.1126/scitranslmed.aau6550
That's very interesting that something as simple as getting a good nights sleep can prevent such a debilitating disease. How would you propose modulating our circadian rhythms in order to get the required amount of sleep each night to clear away these toxic proteins? Is there a specific time frame in which these proteins will clear away over the course of the night or do we just need reach the NREM sleep state?
ReplyDelete