microRNA-146a downregulates IL-17 and IL-35 and inhibits proliferation of human periodontal ligament stem cells

Periodontitis is characterized by increased levels of proinflammatory factors, such as interleukin-17 (IL-17) and IL-35. In this study, the expression of microRNA-146a (miRNA-146a), IL-17, and IL-35 in the plasma of patients with periodontitis and healthy controls were detected by quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. miRNA-146a mimic was transfected into periodontal ligament stem cells (PDLSCs) isolated from periodontitis-affected teeth and healthy teeth. Cell proliferation and expression of IL-17 and IL-35 were detected by cell counting kit-8 assay and Western blot analysis, respectively. It was observed that miRNA-146a was downregulated but IL-17 and IL-35 were upregulated in the plasma of patients with periodontitis than in healthy controls. miRNA-146a was inversely correlated with IL-17 and IL-35 in patients with periodontitis. miRNA-146a overexpression inhibited proliferation of PDLSCs derived from both periodontitis-affected teeth and healthy teeth. miRNA-146a overexpression led to downregulated IL-17 and IL-35 expression in PDLSCs isolated from periodontitis-affected teeth. We, therefore, conclude that miRNA-146a may improve periodontitis by downregulating IL-17 and IL-35 expression and inhibiting proliferation of human PDLSCs.