Wild blueberry polyphenols show promise as periodontal disease therapy

The August 12, 2015 issue of the Journal of Agricultural and Food Chemistry documents the findings of Quebec’s Laval Université of an antibacterial effect for a polyphenol-rich extract of blueberry (Vaccinium angustifolium) against Fusobacterium nucleatum—a bacterium associated with various forms of periodontitis. In addition, blueberry showed an ability to combat inflammation caused by exposure to the bacterium.

Bacterial biofilm or plaque formation on the teeth leads to gum disease that can result in periodontitis, necessitating antibiotic therapy. Authors Amel Ben Lagha and colleagues observe that Fusobacterium nucleatum, in addition to being associated with periodontitis, can also cause other infections, including inflammatory bowel disease, endocarditis and brain abscesses.

Blueberry polyphenols have shown an ability to combat bacteria in the urinary tract; however, their effect in periodontal disease had not been investigated. The current research revealed an antibacterial effect for blueberry against F. nucleatum, which the researchers suggest may be due to blueberry polyphenols’ iron-chelating property. The extract also showed an ability to inhibit F. nucleatum biofilm formation.

In other experimentation, blueberry extract dose-dependently reduced the activation of nuclear factor-kappa beta (NF-KB) by F. nucleatum in human monocytes, indicating reduced inflammation. Pretreatment of F. nucleatum-stimulated macrophages with blueberry extract was shown to reduce the secretion of the cytokines interleukin-1beta, tumor necrosis factor-alpha and interleukin-6, as well as matrix metalloproteinases (MMPs) 8 and 9, which are associated with periodontal tissue destruction.

“We showed that polyphenols in a lowbush blueberry extract are active against the two main etiologic components of periodontitis,” the authors conclude. “On the one hand, the blueberry extract inhibited the growth and biofilm formation of the periodontopathogenic bacterium F. nucleatum. On the other, it reduced the secretion of cytokines and MMPs by macrophages by blocking the activation of the NF-KB signaling pathway. This dual action of lowbush blueberry polyphenols suggests that they may be promising candidates for novel therapeutic agents.”