[IL-17 regulates the expression of RANKL and OPG in human periodontal ligament fibroblasts by activating p38MAPK signaling pathway].

: Objective To illuminate whether IL-17 regulates receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) expression in human periodontal ligament fibroblasts (HPDLFs) via p38MAPK signaling pathway. Methods HPDLFs were incubated in the presence of 20 ng/mL IL-17 for 0, 20, 40, 60 and 80 minutes. HPDLFs were divided randomly into 6 groups: control group, dimethyl sulfoxide (DMSO) group, p38MAPK pathway inhibitor SB203580 group, IL-17 group, IL-17 combined with DMSO group and IL-17 combined with SB203580 group. SB203580 (10 μmol/L) and IL-17 (20 ng/mL) were added to the corresponding groups. Real-time quantitative PCR was used to detect the expression of RANKL and OPG mRNAs in HPDLFs. The levels of phospho-p38MAPK (p-p38MAPK) and RANKL protein were measured using Western blot analysis. The protein level of OPG was detected by ELISA. Results After IL-17 stimulation, the expression level of p-p38MAPK protein gradually increased starting from 0 minute and reached its highest level at 60 minutes. It started to decline at 80 minutes. Stimulation with IL-17 could increase the mRNA and protein expression level of RANKL but decrease the mRNA and protein expression level of OPG. Nevertheless, unlike the IL-17 group, IL-17 combined with inhibitor SB203580 decreased the expression of RANKL mRNA and protein and increased OPG mRNA. Conclusion IL-17 can enhance the expression of RANKL in human periodontal fibroblasts and inhibit the expression of OPG mRNA through the p38MAPK signal transduction pathways.