The plaques that cause gum disease also can play a role in developing heart disease -- meaning oral hygiene is important for more than just people's mouths. Photo by zlikovec/Shutterstock

OREBRO, Sweden, Sept. 11 (UPI) -- Building on evidence that periodontitis, or gum disease, is a risk factor for heart disease, researchers found that a specific periodontal pathogen increases inflammation and atherosclerosis in aortic smooth muscle cells.

Researchers in the study, conducted at Örebro University in Sweden, showed in animal models how the pathogen Porphyromonas gingivalis, which has been found in the coronary artery plaques of heart attack patients, causes genetic changes that increase the inflammation of heart disease.


"Our research clarifies the mechanism behind the association of periodontitis and cardiovascular disease," said Boxi Zhang, a doctoral student at Örebro University, in a press release. "Our aim is to find biomarkers that can help us diagnose and treat both diseases."

Periodonititis is caused by the by the buildup of the bacteria that make up dental plaques at the gumline, often starting as the condition gingivitis. The cause of this generally is poor diet and, more significantly, poor oral hygeine.

Researchers showed that P. gingivalis can cause heart disease by culturing human aortic smooth muscle cells and infecting them with the pathogen. Gingipains, which are produced by the pathogen, increase the expression of the pro-inflammatory gene angiopoietin 2 while decreasing the expression of the anti-inflammatory angiopoietin 1 -- a combination that increases inflammation in aortic muscles.

"Angiopoietin 2 directly increases the migration of aortic smooth muscle cells," Zhang said. "The migration of smooth muscle cells is involved in the pathogenesis of atherosclerosis."

The study is published in Infection and Immunity.