Yes, it’s shocking and it’s true: Periodontitis increases the risk of developing heart disease. A team of researchers have demonstrated that a periodontal pathogen – foreign organism that invades the body and causes disease – alters gene expression which leads to increased inflammation and arthrosclerosis in smooth muscles of the aorta.
Linking The Pathogen To Risk Of Heart Complications
Sufficient circumstantial evidence was available to lead the study. Porphyromonas gingivalis, the periodontal pathogen, has also been discovered in plaques formed in the coronary arteries of patients who suffered a heart attack. Moreover, in two animal models of different species, P. gingivalis has been seen to cause and enhance the formation of aortic and coronary atherosclerosis.
The team of researchers, led by Torbjörn Bengtsson of the Department of Clinical Medicine, School of Health Sciences, Örebro University, Örebro, Sweden, demonstrated exactly how this happened.
The findings were published in Infection and Immunity, a journal of the American Society for Microbiology.
Catching The Culprit In The Act: Dental Hygiene
The investigators cultured human aortic smooth muscle cells, and then infected them with P. gingivalis. They observed that the virulence factors produced by the pathogen, known as gingipains, accelerated the expression of pro-inflammatory angiopoietin 2, and reduced the expression of anti-inflammatory angiopoietin 1. The net effect: increased inflammation of the smooth muscle cells, a symptom significantly associated with atherosclerosis.
The researchers explained that even though unstimulated aortic smooth muscle cells did produce angiopoietin 2 at very low levels, stimulation with the pathogen significantly increased its gene expression.
“Angiopoietin 2 directly boosts the migration of aortic smooth muscle cells”, wrote first author Boxi Zhang, a PhD student in Bengtsson’s laboratory. “This migration is involved in the pathogenesis of atherosclerosis”.
TNF Isn’t The Only One To Be Blamed: Can Good Dental Hygiene Save Your Life?
Similar to ginginpains, tumor necrosis factor (TNF) – a naturally produced inflammatory cytokine and marker for cardiovascular disease risk – also induces and enhances atherosclerosis via angiopoietin 1 and 2. However, the results of this study show that ginginpains works independent of TNF, and is alone a risk factor for cardiovascular ailments.
“Our research simplifies the mechanism behind the association of periodontitis and cardiovascular disease. Our next goal is to identify biomarkers that might help us diagnose and treat both the diseases”, concluded Zhang.