Micro RNA-146a effect on Periodontitis is Independent on OPG/RANKL Axis

Background: MicroRNA-146a (miR-146a) is a regulator of inflammatory response. Periodontitis is a disease with immune pathophysiology of the periodontium in which the inflammation results in the destruction of the soft tissues and alveolar bone. Therefore, this study was investigated whether miR-146a may contribute to periodontitis through affecting the levels of OPG and RANKL. Methods The levels of miR-146a, RANKL, and OPG in gingival tissues from patients with generalized periodontitis stages II and III and grades A and B (n = 15, group A), patients with generalized periodontitis stages III and IV and grade C (n = 15, group B), and healthy individuals (n = 10) were determined by real-time PCR. The associations of miR-146a expression with OPG and RANKL levels were evaluated. Results The levels of miR-146a in two subgroups within periodontitis patients were significantly higher than healthy subjects (P < 0.0001). MiR-146a showed the increased level in group A of patients compared with group B (P < 0.05). Clinical parameters such as probing depth (PD) and clinical attachment loss (CAL) were significantly higher in patients than control group (P < 0.05). The levels of OPG and RANKL were increased in patients compared with healthy subjects, although the elevated levels were not statistically significant. MiR-146a was not associated with the levels of OPG and RANKL. Conclusion The results of this study failed to show the effect of miR-146a on the pathophysiology of disease through OPG/RANKL axis. Clinical Relevancy: MiR-146a may participate in the pathophysiology of disease through independent mechanism(s) of OPG/RANKL axis.