Kallikrein 4 and matrix metalloproteinase-20 immunoexpression in malignant, benign and infiltrative odontogenic tumors

Kallistatin attenuates inflammatory response in rheumatoid arthritis via the NF-κB signaling pathway

Cartilage degeneration and inflammation are important features of rheumatoid arthritis (RA). Chondrocyte inflammation and apoptosis have been increasingly demonstrated to be related to cartilage decomposition. In this study, we analyzed the protective role of kallistatin against RA and its associated mechanisms. We obtained in vitro and in vivo RA models using IL-1β and heat-inactivated Mycobacterium tuberculosis, respectively. Our results showed that kallistatin mitigated IL-1β-mediated chondrocyte apoptosis and inhibited the synthesis of ECM-degrading generation, like matrix metalloproteinase (MMP)-3/13 and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4/5, in IL-1β-mediated chondrocytes. Furthermore, kallistatin markedly suppressed IL-1β-mediated inflammation while decreasing the levels of inflammatory factors and mediators via the NF-κB pathway. Daily administration of kallistatin reduced the expression levels of PGE2, TNF-α, IL-1β, and IL-6. Histochemical analysis revealed that the kallistatin-treated rats exhibited reduced RA severity compared with control mice. In summary, kallistatin suppressed IL-1β-mediated inflammation in chondrocytes via the NF-κB pathway. Administration of kallistatin remarkably inhibited RA development, accompanied by reduced inflammation and apoptosis. Therefore, kallistatin administration can be used as a candidate therapeutic strategy for RA.

Biphasic Functions of Sodium Fluoride (NaF) in Soft and in Hard Periodontal Tissues

Sodium fluoride (NaF) is widely used in clinical dentistry. However, the administration of high or low concentrations of NaF has various functions in different tissues. Understanding the mechanisms of the different effects of NaF will help to optimize its use in clinical applications. Studies of NaF and epithelial cells, osteoblasts, osteoclasts, and periodontal cells have suggested the significant roles of fluoride treatment. In this review, we summarize recent studies on the biphasic functions of NaF that are related to both soft and hard periodontal tissues, multiple diseases, and clinical dentistry.

TNF-α-induced IL-6 and MMP-9 expression in immortalized ameloblastoma cell line established by hTERT

OBJECTIVE

Ameloblastoma (AM) shows locally invasive behaviour. However, biological investigations regarding regulation of gene expression associated with AM pathological features are difficult to perform, because AM cells can be passaged for a few generations due to senescence. We report a newly established immortalized AM cell line, AMB cells, by transfection with human telomerase reverse transcriptase (hTERT). Furthermore, we examined whether TNF-α modulates bone resorption-related genes, IL-6 and MMP-9 in cooperation with TGF-β or IFN-γ.

MATERIALS AND METHODS

Following transfection of an hTERT expression vector into AM cells using a non-viral method, the effects of cytokines on the expressions of IL-6 and MMP-9 mRNA were examined using real-time PCR. TNF-α-induced NF-κB activity was examined by western blotting and transcription factor assays.

RESULTS

AMB cells continued to grow for more than 100 population doublings. Stimulation with TNF-α increased IL-6 and MMP-9 mRNA expressions, as well as NF-κB activation. Furthermore, TGF-β and IFN-γ dramatically increased TNF-α-mediated expressions of MMP-9 and IL-6 mRNA, respectively, while those responses were suppressed by NF-κB inhibitor.

CONCLUSION

We established an immortalized AM cell line by hTERT transfection. TNF-α-mediated regulation of MMP-9 and IL-6 via NF-κB may play an important role in the pathological behaviour of AMs, such as bone resorption.