While the exact mechanisms of this infection are still trying to isolate , a litany of papers argue the deadly spread of Alzheimer's goes way beyond what we used to think.
Now, scientists are saying they've got one of the most definite leads yet for a bacterial culprit behind Alzheimer's, and it comes from a very rare quarter: gum disease.
Potempa, a microbiologist from the University of Louisville, researchers report Porphyromonas gingivalis – the pathogens behind chronic periodontitis (aka gum disease) – in the brains of deceased Alzheimer's patients.
It's not the first time the two factors have been linked.
In separate experiments with mice, together with the increased production of amyloid beta (Aβ), the sticky protein associated with Alzheimer's.
The research team, which is coordinated by pharma startup Cortexyme was co-founded by first author Stephen Dominy, who has not discovered the definitive evidence of Alzheimer's causation. Yet.
"Infectious agents have been implicated in the development and progression of Alzheimer's disease before, but the evidence of causation has not been convincing "Dominy says.
"Now, for the first time, we have solid evidence connecting the intracellular, Gram-negative pathogen, P. gingivalis and Alzheimer's pathogenesis."
In addition, the team identified toxic enzymes called gingipains secreted by the bacteria in the brains of Alzheimer's patients, which correlated with two separate markers of the disease: the tau protein, and a protein tag called the ubiquitin.
brains of deceased people who were never diagnosed with Alzheimer's.
That's important, because while P. gingivalis and the disease have been linked before, it's never been known – to put it simply – Alzheimer's disease or even dementia leads to poor oral care.
The fact that low levels of gingipains were evident even
"Our identification of gingipain antigens in the brains of individuals with AD and so with AD pathology but no diagnosis of dementia argues brain disease P. gingivalis is not a result of poor dental care following the onset of dementia or late-stage disease in middle-aged individuals before cognitive decline. "
Further, a compound formulated by the company called COR388, which is already going through clinical trials with Alzheimer's patients, showed in experiments with mice that it could reduce bacterial load of an established P. gingivalis brain infection, while reducing amyloid-beta production and neuroinflammation.
COR388 – but the research community is cautiously optimistic.
"Alzheimer's," chief scientific.
"Alzheimer's," chief scientific officer David Reynolds from Alzheimer's Research commented in a statement.
"We want to know more about its potential as a treatment for Alzheimer's."
The findings are reported in Science Advances .