Genes Help Gum-Disease Germ Harm Arteries

They could explain how periodontal infections boost heart risks, researchers say

WEDNESDAY, May 24, 2006 (HealthDay News) -- Florida researchers say they've discovered four genes that enable a type of gum disease bacterium called Porphyromonas gingivalis to invade and infect artery cells.

The finding offers one possible explanation for a possible link between gum disease and heart disease.

"Aside from lifestyle and genetic factors, there is increasing evidence that bacterial infections may play a role in heart disease. Porphyromonas gingivalis, an important bacterium that causes gum disease, is also linked to cardiovascular disease. In this study we have identified and studied four genes of P. gingivalis that allow it to infect and survive inside artery cells," researcher Paulo Rodrigues, of the University of Florida, Gainesville, said in a prepared statement.

The study was expected to be presented Wednesday at the American Society for Microbiology meeting, in Orlando.

In previous research, Rodrigues and his colleagues found that P. gingivalis could invade and survive inside human artery cells. In this new study, they created four strains of the bacterium, each with a different gene mutated to disable it. The researchers then tested the four mutated strains of the bacterium to determine if they could invade and survive in artery cells and compared those to a fully functioning version of the bacterium.

"Our study showed that all four mutated strains were defective in invasion of the artery cells and that their ability to survive inside of the cells was diminished. These results show that these four genes play a role in the invasion and survival of P. gingivalis inside artery cells," Rodrigues said.

"The knowledge of how this pathogenic bacterium interacts with artery cells is important and may lead to development of therapeutics and diagnostic tools for the detection and possibly prevention of heart diseases caused by this association," he said.

More information

The American Academy of Periodontology has more about gum disease.

SOURCE: American Society for Microbiology, news release, May 24, 2006
Consumer News