Bacteria responsible for gum disease facilitates development and progression of rheumatoid arthritis

Does gum disease indicate future joint problems? Although researchers and clinicians have long known about an association between two prevalent chronic inflammatory diseases — periodontal disease and rheumatoid arthritis (RA) — the microbiological mechanisms have remained unclear. In an article published today in PLoS Pathogens, University of Louisville School of Dentistry Oral Health and Systemic Diseases group researcher Jan Potempa, PhD, DSc, and an international team of scientists from the European Union’s Gums and Joints project have uncovered how the bacterium responsible for periodontal disease, Porphyromonas gingivalis worsens RA by leading to earlier onset, faster progression and greater severity of the disease, including increased bone and cartilage destruction. The scientists found that P. gingivalis produces a unique enzyme, peptidylarginine deiminanse (PAD) which then enhances collagen-induced arthritis (CIA), a form of arthritis similar to RA produced in the lab. PAD changes residues of certain proteins into citrulline, and the body recognizes citullinated proteins as intruders, leading to an immune attack. In RA patients, the subsequent result is chronic inflammation responsible for bone and cartilage destruction within the joints.