Poor Sleep and Inflamed Gums – What do they have in common?
Recently, both poor sleep and inflamed gums have been implicated in the pathophysiology of Alzheimer’s disease. But before we discuss that, I’d like to remind you of the free resource “Alzforum” – www.alzforum.org – where the latest papers and meeting presentations are presented along with active discussion by many of the leading researchers in the field. I do not know of any other field where such a central repository has been maintained over a long period of time. It’s common for colleagues, patients and even family members to ask me about “the latest breakthrough” that they hear about on the news or read about in the lay press. I find Alzforum the best place for me to get a balanced view of the research that triggered the news report.
Let’s start with sleep. Deep or slow-wave sleep has been recognized to be associated with the clearance of β-amyloid. Last year it was demonstrated that even a single night of sleep deprivation results in significant accumulation of β-amyloid in the brain (β-Amyloid accumulation in the human brain after one night of sleep deprivation Ehsan Shokri-Kojori et. al. Proceedings of the National Academy of Sciences 2018 https://dx.doi.org/10.1073/pnas.1721694115) Gadzooks! Apparently pulling an all-nighter to prepare for an exam has unintended consequences! Although no drugs have been identified that improve deep stages of sleep that normally decrease as we age, recently being rocked has been shown to improve deep sleep (Whole-Night Continuous Rocking Entrains Spontaneous Neural Oscillations with Benefits for Sleep and Memory Aurore A. Perrault et. al. Current Biology 2019 https://dx.doi.org/10.1016/j.cub.2018.12.028). It seems like Elvis was on to something when he sang “I heard the news, there's good rocking tonight!" Aside from β-amyloid, tau has been implicated in Alzheimer’s disease, and recently sleep has been identified as a factor that slows the spread of tau in both mice and man. The sleep-wake cycle regulates brain interstitial fluid tau in mice and CSF tau in humans Jerrah K. Holth et. al. Science 2019 https://dx.doi.org/10.1126/science.aav2546 Check out Alzforum for even more evidence that sleep plays a role in Alzheimer’s disease.
Now for gum disease. You may have recently read news releases about a gum bacterium, Porphyromonas gingivalis, which has been suggested as both a potential trigger for Alzheimer’s disease and also a target for treatment. Using Alzforum I was able to search and go back years reading papers both pro and con about the role of periodontal pathogens and Alzheimer’s disease. There really are some intriguing links. I look forward to reading the results of the clinical trials attempting to intervene with the toxicity of Porphyromonas gingivalis. I distinctly remember attending a medical grand rounds by a young Australian physician identifying a bacterium as the cause of peptic ulcer disease, and hearing the audience laugh at how ridiculous that was. We all knew that ulcers were caused by stress and spicy foods. Of course, Barry Marshall went on to win the Nobel Prize for showing the role of Helicobacter pylori and ulcers, so I think I am now more open-minded when hearing such audacious ideas presented. Meanwhile I intend to brush regularly, and I suggest you do as well. And I suggest using Alzforum to help you familiarize yourself with the science behind what otherwise might be “fake news” in the lay press.