Comparison of miRNA expression profiles in individuals with chronic or aggressive periodontitis.

Objectives: MicroRNAs (miRNAs) may play an important role in inflammatory response. However, the involvement of miRNAs in the pathogenesis of periodontitis is unclear. The present study aimed to compare the miRNA expression profiles in individuals with chronic (CP) or aggressive (AP) periodontitis. Materials and methods: Eighteen non‐smoker individuals (CP = 9 and AP = 9) without any history of systemic diseases or previous periodontal therapies were selected at the Clinics of Periodontology from the Federal University of Minas Gerais. Gingival tissue samples were collected during the initial periodontal therapy. miRNAs were isolated, and expression patterns of 754 miRNAs were assessed with a quantitative miRNA PCR array. miRNAs expression profiles were compared between CP and AP groups. Results: There were no differences observed in the miRNAs expression profiles between CP and AP (p > 0.05). According to the microarray analyses, the most expressed miRNAs in both groups were hsa‐miR‐1274b, hsa‐let‐7b‐5p, hsa‐miR‐24‐3p, hsa‐miR‐19b‐3p, hsa‐miR‐720, hsa‐miR‐126‐3p, hsa‐miR‐17‐3p and hsa‐miR‐21‐3p. Conclusion: Findings suggested no differences in miRNAs expression profiles between chronic and aggressive forms of periodontitis. The overexpression of specific miRNAs could provide insights into the pathogenesis of both forms of the disease. [ABSTRACT FROM AUTHOR]