Mechanisms and treatment of periodontal infection and associated systemic inflammation

Periodontitis is an oral disease characterized by destruction of the tooth-supporting tissues and is the most common inflammatory disorder of humans affecting about 40% of the adult population aged 50 years and above, i.e. around 1 million people in Sweden. Periodontitis is also considered to contribute to several systemic disorders such as cardiovascular disease, rheumatoid arthritis, diabetes, stroke, Alzheimers disease and cancer. To date, the cellular and molecular mechanisms by which infectious agents contribute to periodontitis and associated systemic diseases, including the interplay between microbial antigens and the innate and adaptive immune system, are not well understood. Porphyromonas gingivalis is considered to play a major causative role in the etiology of periodontal disease, mainly by expressing a high proteolytic activity through gingipains. Frequent periodontitis-induced bacteraemias involving P. gingivalis may induce systemic inflammation and are suggested to stimulate and maintain a chronic state of inflammation in atherosclerotic vessels leading to myocardial infarction. The focus in this area today is to elucidate the role of periodontal bacteria and their enzymes in the development of Alzheimers disease in a project including several researchers, clinicians and dentists at Örebro University and Örebro University Hospital. There are currently no methods available to track either early stages of periodontitis or the immunological and vascular response to transient or continuous bacteremias in patients with periodontitis and therefore predict the risk for systemic inflammation. Furthermore, current preventive therapies of periodontitis with antibiotics and anti-inflammatory agents are ineffective, arguing for other approaches, e,g, anti-bacterial peptides (bacteriocins). We have recently reported that a specific bacteriocin, PLNC8ab, efficiently inhibits and kills P. gingivalis, suggesting that this peptide can be used in the prevention and treatment of periodontitis and associated systemic disorders.