The findings suggest that it may be beneficial to test periodontitis patients for changes in their plasma lipoprotein profiles, so that available medication can be taken if necessary.
In the December issue of the Journal of Lipid Research, researchers found that patients with generalized aggressive periodontitis generally had elevated plasma levels of a particularly bad subclass of the low density lipoprotein (LDL) called small-dense LDL.
"Previous research has shown that people who have predominantly small-dense LDL in their blood are at a three- to six-fold increased risk of heart disease and stroke", said lead author Rik van Antwerpen, Ph.D., an assistant professor of biochemistry at VCU. "A person may have predominantly small-dense LDL without having alarmingly high blood levels of cholesterol. Therefore, unhealthy levels of small-dense LDL are not always detected in regular cholesterol tests."
According to the study, a second factor influencing the cardiovascular risk of patients with severe periodontitis may be platelet activating factor acetylhydrolase (PAF-AH), an enzyme that is associated with small-dense LDL. PAF-AH is able to break down some of the inflammatory, atherogenic components of LDL. Van Antwerpen said that the enzyme may lower the atherogenic effects of LDL, and that the observed decrease of LDL-associated PAF-AH activity in patients with severe periodontitis may increase the cardiovascular risk of these patients.
"Our results indicate that these differences may in part be responsible for the enhanced plaque build up in the arteries of patients with severe periodontitis," said van Antwerpen.
In this study, a limited number of participants were enrolled – 12 patients with generalized aggressive periodontitis and 12 control subjects without periodontal disease. Currently, van Antwerpen and his colleagues are evaluating a greater number of patients with varying degrees of periodontal infection and inflammation as they work toward establishing testing guidelines for periodontitis patients.
Van Antwerpen collaborated with Harvey A. Schenkein, Ph.D., Director of the Clinical Research Center for Periodontal Diseases, and chair of the Department of Periodontics, VCU School of Dentistry; Suzanne E. Barbour, Ph.D., associate professor in the Department of Biochemistry, VCU School of Medicine; John G. Tew, Ph.D., professor in the Department of Microbiology and Immunology, VCU School of Medicine. Experiments were carried out by Miguel Rufail, a graduate student in the VCU Department of Biochemistry.
This research was supported by grants from the National Institutes of Health.
About VCU and the VCU Medical Center: Located on two downtown campuses in Richmond, Va., Virginia Commonwealth University is ranked nationally by the Carnegie Foundation as a top research institution and enrolls more than 28,500 students in more than 181 certificate, undergraduate, graduate, professional and doctoral programs in the arts, sciences and humanities in 15 schools and one college. Forty of the university's programs are unique in Virginia, and 20 graduate and professional programs have been ranked by U.S. News & World Report as among the best of their kind. MCV Hospitals, clinics and the health sciences schools of Virginia Commonwealth University compose the VCU Medical Center, one of the leading academic medical centers in the country. For more, see www.vcu.edu.
Journal
Journal of Lipid Research