In recent years, a growing number of scientific studies have supported an alarming hypothesis: Alzheimer's disease is not just a disease but an infection.
While the exact mechanisms of this infection are still trying to isolate, a file of papers argue that the lethal spread of Alzheimer's disease goes far beyond what we are accustomed to thinking.
Now scientists say they have one of the most definite causes of the bacterial culprit behind Alzheimer's disease, and it comes from a little unexpected quarter: gum disease.
In a new book led by senior author Jan Potterpa, a microbiologist at the University of Louisville, researchers report the discovery of Porphyromonas gingivalis ̵
This is not the first time the two factors are related, but the researchers go further. individual experiments with mice, oral pathogen infection led to bacterial colonization of the brain, along with increased production of amyloid beta (Aβ), sticky proteins often associated with Alzheimer's.
The research team, co-ordinated by Cortexyme's pharmaceutical start, co-founder of the first author, Stephen Dominini, does not claim to have found conclusive evidence of the cause of Alzheimer's disease.
But it is clear that they think we have a strong line of investigation here. "Infectious agents are involved in the progression and progression of Alzheimer's disease before, but evidence of a causal relationship is not convincing," Domini said.
"For the first time, we have solid evidence linking the intracellular gram-negative pathogen, P. Gingivalis and Alzheimer's pathogenesis."
In addition, the team identified toxic enzymes called gypsies secreted by bacteria in the brains of Alzheimer's who correlate with two distinct markers of the disease: tau protein and a protein label called ubiquitin.
But even more convincingly, the team has identified these toxic gingivan in the brains of deceased people who have never been diagnosed with Alzheimer's disease
This is important because while P. gingivalis and the disease has been associated before, it has never been known – just to say – whether gum disease causes Alzheimer's disease, or whether dementia leads to poor oral hygiene.
The fact that low levels of gingivan are obvious even in people who have never been diagnosed with Alzheimer's disease may be a smoking tool – suggesting that the condition may have developed if they lived longer. the diagnosis of dementia claims that the P. gingivalis brain infection is not the result of poor dental care after the onset of dementia or the consequence of a late stage of the disease, but is an early event that can explain the pathology found in middle- age before cognitive decay, "the authors write in their article.
Furthermore, a compound formulated by the company called COR388, which already goes through clinical trials with Alzheimer's patients, has shown in experiments with mice that it can reduce the bacterial burden of established P. gingivalis brain infection, while reducing the production of amyloid-beta and neuroinflammation.
We will have to wait and see what future research will be about this relationship – and the potential benefits of COR388 – but the research community is cautiously optimistic.
"To date, drugs directed against toxic bacterial proteins have shown an advantage only for mice, but without new treatments for dementia for more than 15 years, it is important to test as many approaches as possible to tackle diseases such as Alzheimer's disease" , Chief Scientist David Reynolds of the Alzheimer's study commented in a statement.
"We will have to see the outcome of this ongoing process before we know more about its potential for treating Alzheimer's disease."
The findings are reported in Scientific Achievements .