Purpose: The present study was performed to assess the associations of gingival crevicular fluid (GCF) microRNAs miR-140-3p, miR-145-5p, miR-146a-5p, and miR-195-5p with periodontitis (PD) and to evaluate the possible influence of rheumatoid arthritis (RA) in this context.
Method: GCF samples were collected from 134 individuals with PD and 76 periodontally healthy individuals, with or without RA. After miRNA extraction from GCF, the levels of miR-140-3p, miR-145-5p, miR-146a-5p, and miR-195-5p were assessed using RT-qPCR.
Results: MiR-146a-5p levels were significantly lower among the patients with PD than among the healthy individuals (P < 0.001) and negatively correlated with PD severity based on PD stage and periodontal outcome parameters (P < 0.05). Patients with severe PD had higher GCF levels of miR-140-3p and miR-145-5p than did periodontally healthy individuals (P < 0.05). Significant AUC values for diagnosis of severe PD were revealed for miR-140-3p (AUC = 0.614, P = 0.022), miR-145-5p (AUC = 0.621, P = 0.016) and miR-146a-5p (AUC = 0.702, P < 0.001). Combination of the aforementioned miRNAs increased the diagnostic performance (AUC = 0.709, P < 0.001).
Conclusion: It was demonstrated that miR-140-3p, miR-145-5p and miR-146a-5p were associated with PD and would be potentially effective for GCF-based non-invasive periodontitis diagnostics in patients with and without RA.
Keywords: biomarker; microRNA; periodontitis; rheumatoid arthritis.