TLR4 immunoreactivity was found in healthy gingival epithelium and periodontitis tissue, and appeared to be lower in junctional epithelium ( p ≤ 0.01).
In conclusion, these novel findings indicate that baicalin inhibits the TLR2 and TLR4 expression and the downstream signaling and mitigates inflammatory responses and the alveolar bone loss in rat experimental periodontitis.
We investigated the effects of a synthetic GAG, GM-0111, on various molecular events associated with periodontitis: growth of Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) pathogenic bacteria associated with periodontitis; activation of pro-inflammatory signaling through TLR2 and TLR4 in mouse macrophage RAW 264.7 cells and heterologously expressed HEK 293 cells; osteoclast formation and bone matrix resorption in cultured mouse pre-osteoclasts.
Gene expressions of IL-17, TNF-a, OPG, RANKL, TLR-2, and TLR-4 were higher in periodontitis, when compared to periodontally healthy sites (P < 0.05), while no differences between groups were observed for the other genes evaluated (P > 0.05).
On the other hand, while the sTLR-2 and the paired epithelial cell associated TLR-2 mRNA exhibited a direct correlation (r2 = 0.62), that of sTLR4 and TLR-4 mRNA exhibited an inverse correlation (r2 = 0.53) in the periodontitis cohort.
In addition, miR-22-3p also upregulated the expression levels of the inflammatory cytokines tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-8 in PDLSC through SIRT1 pathway and downregulated the expression of TLR-2 and TLR-4. miR-22-3p is a new target either for the treatment of periodontitis or the improvement of inflammation caused by orthodontics.