What's more, autopsies have shown that protein plaques can appear in people who had no Alzheimer's disease. What's not clear is whether gum disease causes the disorder or is merely a result-many patients with dementia can't take care of their teeth, for example. Since the study's publication, the neurologists are planning to expand their research to include more patients.
"This is something that would be easy to incorporate into a screening test in a neurology clinic", says study coauthor Brian Gordon, assistant professor of radiology at Washington University's Mallinckrodt Institute of Radiology. "I'm fully on board with the idea that this microbe could be a contributing factor". The scientists then tested the brains of 53 people with Alzheimer's disease, finding the toxic enzymes from P.?gingivalis in 51 of them.
The study, which is coordinated by the pharmaceutical startup Cortexyme and co-founded by Dominy, developed a series of molecule therapies that target Pg gingipains. Some had HIV-related dementia that resolved after they got antiviral drugs.
Does gum disease play a key role in the development of Alzheimer's? They also demonstrate the presence of P. gingivalis DNA in post-mortem Alzheimer's brain samples (both hippocampus and cerebral cortex) and in the CSF of living patients who are believed to have the disease as well.
Could these protein plaques be simply byproducts of the brain's defense mechanisms in the face of the real Alzheimer's causing germ? Another physical characteristic of the Alzheimer's diseased brain is the buildup of tau proteins, which tangle inside neurons, blocking their transport system. That early appearance is important, Lynch says, because "you would expect it to be there before the onset" of symptoms. This same bacteria causes periodontal disease which creates gum infection and potential tooth loss when left untreated.
Iranian soldiers among 21 killed in Israeli strike on Syria
But this time the missile strikes took place during the day and Israeli officials openly took responsibility for them. The army has moved additional Iron Dome batteries to the north, and the Israeli air force is on constant alert.
Edelmayer also cautions not to put too much weight on drugs tested in mice. They used a compound that targeted the gingipains, which likely supply nutrients to the bacteria, to successfully kill off the bacteria, reducing neurodegeneration and the formation of beta-amyloid protein. Chief executive Casey Lynch said: 'This study is an important breakthrough in understanding how Alzheimer's disease can be triggered and a new path to treatment'. A larger study is slated to start this year.
"Infectious agents have been implicated in the development and progression of Alzheimer's disease before", Dominy said in a statement.
Previous studies have found that detecting high levels of NLP in a person's cerebrospinal fluid indicate that some of his brain cells have been damaged and he is at risk of Alzheimer's and other neurological diseases. "These are unusual ideas, but they seem to be getting some traction".
In the United Kingdom, there are 850,000 people living with dementia, Alzheimer's disease is the most common type of this condition, according to the Alzheimer's Society in the UK.
Statistics record that as many as one in 14 over the age of 65 will be affected by one form or another of dementia. But he stressed this won't prevent the brain from becoming infected by P. gingivalis.