The expression of nuclear factor of activated T cell c1 and receptor activator of nuclear factor kappa β induced by Enterococcus faecalis in osteoclastogenesis (laboratory experiment on Wistar rats)

Abstract

Background: Enterococcus faecalis (E. faecalis) is the most common bacteria species in persistent endodontic infection of teeth undergoing root canal treatment at a prevalence of 38%. The virulence factor of this bacterium is Lipoteichoic acid (LTA) which can be recognized by Toll-like receptors-4 (TLR-4) that produce a stimulus and provoke an immune response. Inflammation results in bone defects that feature multiple cytokines and interactions between different cell types. Bone loss within a periapical tooth is characterized by osteoclast formation (osteoclastogenesis) in the bone. Purpose: This study aimed to determine the expression of nuclear factor of activated T cell c1 (NFATc1) and receptor activator of nuclear factor kappa β (RANK) which played a role in osteoclastogenesis at different time intervals. Methods: 36 upper molar teeth of the research subjects were induced with 106 CFU Enterococcus faecalis and subsequently observed for 7 and 21 days with the NFATc1 and RANK being counted microscopically at 1000X magnification across 20 viewing fields. Thereafter, the data was examined and analyzed by means of an independent T test using SPSS. Results: NFATc1 and RANK expression were higher in the group including E. faecalis on days 7 and 21 than in the control group. There were significant differences between the treatment group and control group with regard to NFATc1 and RANK expression (p<0.05). Conclusion: The study showed that the expression of NFATc1 and RANK, which plays a role in osteoclastogenesis, was higher in periapical bone defects in Wistar rats induced by E. faecalis than those which were not induced.

NFkB and MMP-13 expression in condylar cartilage of temporomandibular joint with occlusal disharmony in vivo

“…18 Several studies mentioned that NFκB is the main inflammatory mediator in rheumatoid arthritis and cancer, cervical cancer, nasopharyngeal carcinoma, periapical lesions and TMJ osteoarthritis. [19][20][21][22][23] Activation of NFκB in the synovial layer also occurred among mice that had synovitis caused by a mechanical stress response due to excessive pressure. 24 NFκB expression was shown to be higher on the 7 th and 14 th days and was at its highest on the 21 st day.…”

“…These results were similar to previous studies that showed that NFκB expression was detected on the 15 th day of observation and played a role in TMJ cartilage damage. 19,21 The occlusal reduction on the right molar in animal groups made premature contact on the collateral side. The occlusal disharmony caused by occlusal reduction induces the excessive stimulation of mechanic sensors at the periodontal ligament and is related to an increase in mastication activities, including in the muscles and the TMJ.…”