Published here on Aug 11, 2019
Alzheimer’s disease is one of the most feared illnesses afflicting older adults. Just ask anyone over the age of 55 who has misplaced car keys whether they didn’t have a momentary fear it could be a first sign of the crippling slow decline associated with this disease.
Most of what Doctors diagnose as “dementia” is Alzheimer’s disease (about 70% of dementia cases). With our rapidly aging populations, Alzheimer’s has become the 5th leading cause of death in the U.S. As a result, many of us have witnessed the heartbreak and despair of watching a loved one’s progressive memory loss and brain function resulting in the eventual but often slow death of the person they once knew. We watch our family members disintegrate in slow motion before our eyes and pray that we never meet the same fate.
Throughout the years, a lot of Alzheimer’s research focused on how the characteristic amyloid deposits on the brain are formed and exploring the role of inflammation in the disease progression. These amyloid proteins form large sticky plaques on the brain and are a hallmark of the disease and an early indicator of Alzheimer’s.
But finally, after decades of scientific failure and billions of dollars spent in looking for a cure along with a 99% failure rate in drug treatment research, there is a bright ray of hope that may lead to a long-sought-after treatment.
But, this periodontal disease connection intrigued an international team of scientists and they decided to take a more in-depth look at the role of gum disease in Alzheimer’s. And they have published some truly intriguing results.
It was a complex series of studies worked on by several groups of scientists. So I’m going to try and break it down for you: First, they analyzed cerebrospinal fluid (considered a “window” into brain infection) from 10 living patients diagnosed with probable Alzheimer’s disease. Then they isolated DNA from Porphyromonas gingivalis (Pg), the primary pathogen found in chronic periodontitis, matching it with the Pg that the researchers found in the patients’ saliva samples.2
Next, the researchers looked at the toxic enzymes produced by Pg called “gingipains,” and analyzed brain-bank samples from deceased people. One team found that there were greater gingipain loads in the brains of people who died from Alzheimer’s disease than in the brains of people who had no diagnosis of dementia.3
This new information quickly led them to the conclusion that Pg “is not a result of poor dental care following the onset of dementia or a consequence of late-stage disease, but is an early event that can explain the pathology found in middle-aged individuals before cognitive decline.”2
Now for the fascinating part of the study. The team tested a molecular therapy already undergoing clinical trials on Alzheimer’s patients to see if the compound, called COR388, could inhibit the toxic action of gingipains in the brains of mice that had been orally infected with gingipains. They found that not only was there reduced bacterial load of Pg brain infection, COR388 also blocked amyloid beta production, and reduced neuroinflammation.
Overall this added up to more protection of neurons in the hippocampus—the part of the brain that controls memory and is damaged early in the development of Alzheimer’s.4
What Does This Mean For Everyday People?
Dr. Jan Potempa, an investigator based at the University of Louisville’s Department of Oral Immunology and Infections Disease who was part of the international team said, “We now have strong evidence connecting P. gingivalis and Alzheimer’s pathogenesis (the chain of events leading to the disease)…”
An even more critical aspect of this study is that there might be enormous potential for therapies that could change the course of the disease or even stop the progression of a disease that now seems to be strongly connected with this particular dental disease and bacteria.4 Researchers are now focusing on developing a compound like COR388 that can effectively block the debilitating effects of Pg in the brain.
Also, consider this, there is a link between gum disease and other conditions such as heart disease and diabetes. The research here is also not conclusive, but there is some evidence that suggests that there is a connection and more research is underway.
According to The Mayo Clinic5 :
“Gum disease (periodontitis) is associated with an increased risk of developing heart disease.”
“Poor dental health increases the risk of a bacterial infection in the bloodstream, which can affect the heart valves. Oral health may be particularly important if you have artificial heart valves.”
“Tooth loss patterns are connected to coronary artery disease.
“There is a strong connection between diabetes and cardiovascular disease and evidence that people with diabetes benefit from periodontal treatment.”
Bottom line: Though this line of investigation is still young and COR388 may not prove to be a magic bullet (or the only magic bullet) against Alzheimer’s disease, this research is very encouraging, and we will continue to update this article with any new studies. Until then, it certainly makes sense to maintain good oral hygiene practices (regular brushing and flossing) and visit a dentist regularly to catch gum disease as early as possible!
1Kamer AR et al. Periodontal disease associates with higher brain amyloid load in normal elderly. Neurobiology of Aging. 2014;36(2):627-33. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4399973/
2Dominy SS et al. Porphyromonas gingivalis in Alzheimer’s disease brains: Evidence for disease causation and treatment with small-molecule inhibitors. Science Advances. 2019. http://advances.sciencemag.org/content/5/1/eaau3333
3Yager J. Are Brains with Alzheimer Disease All Gummed Up? 8 February 2019. NEJM Journal Watch. https://www.jwatch.org/na48441/2019/02/08/are-brains-with-alzheimer-disease-all-gummed
4 The University of Louisville. School of Dentistry. New science details discovery of bacterial pathogen in brains of Alzheimer’s patients. January 2019. https://louisville.edu/dentistry/news/new-science-details-discovery-of-bacterial-pathogen-in-brains-of-alzheimer2019s-patients-and-possible-evidence-of-disease-causation
5 Heart disease prevention: Does oral health matter? – Mayo Clinic Online. https://www.mayoclinic.org/healthy-lifestyle/adult-health/expert-answers/heart-disease-prevention/faq-20057986
Photo credit: Alzheimer’s disease has destroyed neurons in the right-hand brain above. Jessica Wilson/Science Photo Library