Dysregulation of miR-146a by periodontal pathogens: A risk for acute coronary syndrome.

BACKGROUND: Periodontitis is a polymicrobial, chronic inflammatory disease leading to loss of tooth-supporting structures. The bacteremia, endotoxemia, and systemic low-grade inflammation associate periodontitis with systemic illnesses such as diabetes mellitus and coronary artery disease. Periodontal pathogens have been detected from atheromatous plaque by amplification of the genetic material by using specific oligonucleotide primers in polymerase chain reaction. Though the association between periodontitis and cardiovascular diseases has been ascertained by systematic reviews and meta-analyses, its pathophysiology is not lucid. MicroRNAs are currently implicated in the regulation of many cellular processes including inflammation and may play a vital role in our understanding of this disease association. In this case-control study, we explored the role of the inflammatory microRNA, miR-146a in Acute Coronary Syndrome (ACS) subjects with and without chronic periodontitis (CP) and its regulation of the innate immune host response to periodontal pathogens.

METHODS: Three groups each comprising of 66 patients each, namely Group I (ACS patients without CP), Group II (ACS patients with CP) and Group III (CP only) formed the study population. Subgingival plaque samples and serum samples were subjected to qPCR for detection of P.gingivalis, a keystone pathogen and to assess the levels of circulating miR-146a and associated pro-inflammatory cytokines.

RESULTS: miR-146a associated significantly in Group II subjects with an OR 1.434, 95%CI 1.013-2.030, p < 0.042, and a predictive percentage of 83.3 and Group I with a predictive percentage of 76.0. The associated cytokines IL-6, TNF-α and IL-1β also showed an up regulation with statistical significance (p < 0.05).

CONCLUSION: microRNA-146a is a key molecule associating periodontitis with acute coronary syndrome. This article is protected by copyright. All rights reserved.