Research finds oral bacterial imbalance linked to Alzheimer’s disease

In the light of increasing evidence of a link between periodontitis and Alzheimer’s disease, researchers at the New York University (NYU) College of Dentistry and Weill Cornell Medicine have revealed that older adults with a preponderance of harmful bacteria in their mouth have shown greater evidence of amyloid beta, of the main biomarkers for Alzheimer’s disease, in their cerebrospinal fluid.

However, according to an article in Dentistry Today, this imbalance between harmful and bacteria “was not associated with another Alzheimer’s biomarker called tau.”

Speaking about the results of their research, lead author Angela Kamer, DDS, PhD, associate professor of periodontology and implant dentistry at the NYU College of Dentistry had this to say:

“To our knowledge, this is the first study showing an association between the imbalanced bacterial community found under the gumline and a CSF biomarker of Alzheimer’s disease in cognitively normal older adults.

“The mouth is home to both harmful bacteria that promote inflammation and healthy, protective bacteria. We found that having evidence for brain amyloid was associated with increased harmful and decreased beneficial bacteria.”

Acknowledging that much research remains to be done to understand fully Alzheimer’s pathology, senior author Mony J. de Leon, EdD, professor of neuroscience in radiology and director of the Brain Health Imaging Institute at Weill Cornell Medicine spoke of their benefits of this study.

“The present study adds support to the understanding that proinflammatory diseases disrupt the clearance of amyloid from the brain, as retention of amyloid in the brain can be estimated from CSF levels. Amyloid changes are often observed decades before tau pathology, or the symptoms of Alzheimer’s disease are detected.”

The findings of this research are promising with researchers hypothesising that the higher the levels of good bacteria, which maintain overall bacterial balance, the more protection afforded to someone from developing the inflammation that plays a role in the development of Alzheimer’s disease.

For more on this story, go to “Gum Bacteria Imbalance Linked to Alzheimer’s Disease Biomarker”

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