Every time you go to the dentist, they give you the gentle reminder to floss. Do you heed that advice? If not, you may want to start adding flossing to your evening bedtime regime. If your teeth bleed when you brush, that’s a possible sign that you might have gum disease. A new study released by Cortexyme, a pharmaceutical firm in San Francisco, makes it all the more compelling that proper dental health should be a top priority for all.
THE GUM DISEASE-BACTERIA CONNECTION
According to a study published in New Scientist, there’s a possibility that we may have found a long-unidentifiable cause of Alzheimer’s disease — Porphyromonas gingivalis— the key bacteria in chronic gum disease.
Gum disease is prolific, affecting around a third of the population. However, a new drug that blocks the main toxins in P. gingivalis will enter clinical trials in 2019. Research that was published last week reveals that the drug might have the ability to stop — and even reverse — Alzheimer’s. There’s even hope that a vaccine could be on the horizon.
THE ROOTS OF ALZHEIMER’S
Despite being a major source of study for decades, Alzheimer’s remains one of the largest medical mysteries. In recent years, dementia has become the fifth biggest cause of death worldwide. Alzheimer’s constitutes some 70 per cent of these cases and yet, we still haven’t been able to figure out what causes it.
We know that accumulation of proteins called amyloid and tau are present in the brains of affected individuals. It’s believed that the cause of the disease is from proliferation of these plaques.
However, recent research reveals that amyloid plaques can be develop without the presence of dementia. Therefore, the many endeavors to treat Alzheimer’s by targeting these proteins have been unsuccessful and led to questioning of a long-held scientific belief.
P. GINGIVALIS BREAKTHROUGH
Research teams have been exploring P. gingivalis and have discovered that it invades and inflames brain regions affected by Alzheimer’s. They’ve also ascertained that the presence of gum infections have worsened symptoms in mice genetically engineered to have Alzheimer’s. Finally, they’ve found the bacteria’s presence can lead to Alzheimer’s-like brain inflammation, neural damage, and amyloid plaques in healthy mice.
“When science converges from multiple independent laboratories like this, it is very compelling,” Casey Lynch of Cortexyme shared with New Science.
In the new study, Cortexyme has now reported finding the toxic enzymes — identified as gingipains — that P. gingivalis uses to feed on human tissue in 96% of the 54 Alzheimer’s brain samples they looked at. They found the bacteria in all three Alzheimer’s brains whose DNA they examined.
“This is the first report showing P. gingivalis DNA in human brains, and the associated gingipains, co-localizing with plaques,” Sim Singhrao, of the University of Central Lancashire, UK, reported in the New Scientist. The work of her team also discovered P. gingivalis invades the brains of mice with gum infections.
Gingivalis bacteria and its enzymes were found at higher levels in those who had experienced worse cognitive decline, and had more amyloid and tau accumulations. The team also found the bacteria in the spinal fluid of living people with Alzheimer’s, suggesting that this technique may provide a long-sought after method of diagnosing the disease.
P. GINGIVALIS MICE TRAILS
When the team gave P. gingivalis gum disease to mice, it led to brain infection, amyloid production, tangles of tau protein, and neural damage in the regions and nerves normally affected by Alzheimer’s.
Cortexyme had previously developed molecules that block gingipains. Giving some of these to mice reduced their infections, halted amyloid production, lowered brain inflammation and even rescued damaged neurons.
The team found that an antibiotic that killed P. gingivalis did this too, but less effectively, and the bacteria rapidly developed resistance. However, they did not resist the gingipain blockers. This discovery givers hope that there may one day be treatment or even prevention against Alzheimer’s disease.
HOPE ON THE HORIZON
The study also looked at brain samples from people who had not developed Alzheimer’s who also had the presence of P. gingivalis and protein accumulations, but at lower levels. We’ve already discovered that amyloid and tau can accumulate in the brain for 10 to 20 years before Alzheimer’s symptoms begin. Researchers believe this indicates that P. gingivalis could be a causeof Alzheimer’s, but it is not a result.
Gum disease is far more common than Alzheimer’s. But “Alzheimer’s strikes people who accumulate gingipains and damage in the brain fast enough to develop symptoms during their lifetimes,” Lynch reported to New Science. “We believe this is a universal hypothesis of pathogenesis.”
Cortexyme released a report in October that their optimal gingipain blockers had passed initial safety tests in people, and entered the brain. It also seemed to improve the symptoms of participants with Alzheimer’s. Later this year Cortexyme will embark upon a larger trial of the drug, looking for P. gingivalis in spinal fluid, and cognitive improvements, before and after.
A part of their plan is to test their blocker against gum disease. A team in Melbourne developed a vaccine for P. gingivalis that went into testing in 2018. Dentists and gum disease suffers the world over would rejoice if there was a vaccine that could eliminate gum disease. But the implications if that same same vaccine could halt the march of Alzheimer’s disease would be nothing short of miraculous.
If you found this article informative, check out our blog “Breaking News: Possible New Alzheimer’s Treatment Discovered” that details a half-century old antibiotic researchers are working on as a treatment option.