Effects of Enterococcus faecalis LTA on RANKL and OPG Expression in Periodontal Ligament Fibroblasts , Abstract Aim To investigate the influence of Enterococcus faecalis lipoteichoic acid (LTA) on the key bone resorption-regulating proteins, receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in human periodontal ligament fibroblasts (PDL cells). Methodology PDL cells were subjected to various concentrations of LTA. Cell viability was then determined by MTT assay, while the expression levels of RANKL and OPG were investigated by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The effect of the inhibitors (IL-1 receptor-associated kinase (IRAK)-1/4, p38 Mitogen-activated protein kinase (MAPK) (SB203580)) on LTA-stimulated RANKL/OPG activation was examined. Cell viability and RANKL/OPG ratio in PDL cells were also analyzed by MTT assay and Western blotting. Data were analyzed using one-way anova or t-test at a significance level of P = 0.05. Result Cell viability was reduced significantly in the LTA group in a dose-dependent fashion (P \u003C 0.05). In addition, LTA was found to upregulate the protein expression of RANKL, OPG and their relative ratio in PDL cells (P \u003C 0.05). The optimal concentration of LTA used in PDL cells was determined to be 10 μg mL-1. Following IRAK1/4 and p38MAPK inhibition, LTA-stimulated increases of RANKL/OPG ratio were significantly reduced (P \u003C 0.05). Conclusion E. faecalis LTA could upregulate the expression of RANKL and OPG at different rates, suggesting a potential role for LTA in the bone resorption process of refractory apical periodontitis through the regulation of RANKL and OPG. In addition, IRAK1/4 and p38MAPK signaling involving RANKL/OPG may contribute to inflammatory responses from PDL cells. This article is protected by copyright. All rights reserved. , http://bit.ly/ZkwA1l

Effects of Enterococcus faecalis LTA on RANKL and OPG Expression in Periodontal Ligament Fibroblasts , Abstract Aim To investigate the influence of Enterococcus faecalis lipoteichoic acid (LTA) on the key bone resorption-regulating proteins, receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) in human periodontal ligament fibroblasts (PDL cells). Methodology PDL cells were subjected to various concentrations of LTA. Cell viability was then determined by MTT assay, while the expression levels of RANKL and OPG were investigated by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The effect of the inhibitors (IL-1 receptor-associated kinase (IRAK)-1/4, p38 Mitogen-activated protein kinase (MAPK) (SB203580)) on LTA-stimulated RANKL/OPG activation was examined. Cell viability and RANKL/OPG ratio in PDL cells were also analyzed by MTT assay and Western blotting. Data were analyzed using one-way anova or t-test at a significance level of P = 0.05. Result Cell viability was reduced significantly in the LTA group in a dose-dependent fashion (P \u003C 0.05). In addition, LTA was found to upregulate the protein expression of RANKL, OPG and their relative ratio in PDL cells (P \u003C 0.05). The optimal concentration of LTA used in PDL cells was determined to be 10 μg mL-1. Following IRAK1/4 and p38MAPK inhibition, LTA-stimulated increases of RANKL/OPG ratio were significantly reduced (P \u003C 0.05). Conclusion E. faecalis LTA could upregulate the expression of RANKL and OPG at different rates, suggesting a potential role for LTA in the bone resorption process of refractory apical periodontitis through the regulation of RANKL and OPG. In addition, IRAK1/4 and p38MAPK signaling involving RANKL/OPG may contribute to inflammatory responses from PDL cells. This article is protected by copyright. All rights reserved. , http://bit.ly/ZkwA1l , via Dental Teach " Daily Dental Info " http://www.facebook.com/photo.php?fbid=582976388393581&set=a.582976205060266.1073741849.110664842291407&type=1