Study progress of the correlation between peri-implantitis, IL-1β, TNF-α and NF-κB signal transduction / 口腔疾病防治

@#Increasing numbers of edentulous patients and patients with dental defects are willing to accept implant restorations. However, the development of peri-implantitis is a major factor leading to implant failure. The worsening of peri-implantitis promotes the secretion of inflammatory cytokines such as IL-1β and TNF-α and the gene expression of RANKL, inhibits the gene expression of OPG, and increases osteoclast activity, which promotes bone absorption indirectly and leads to a negative balance in bone metabolism. To gain knowledge about the relationship between peri-implantitis and NF-κB signaling pathways, this article summarizes related reports about peri-implantitis and NF-κB signaling pathways, explores the regulatory mechanism by which peri-implantitis affects bone metabolism and NF-κB signaling, discusses the effect of immunological cytokines on NF-κB signaling pathways when inflammation arises, and provides a theoretical foundation for peri-implantitis research and prevention.

Intra-articular injection of ozone on serum receptor activator for nuclear factor-κB ligand and osteo-protegerin level in collagen-induced arthritis rats / 中华风湿病学杂志

Objective To evaluate the clinical efficacy of intra-articular injection of ozone in collagen-induced arthritis (CIA) rats and to assess its effects on serum receptor activator of nuclear factor κB ligand (RANKL) and osteoprotegerin (OPG) levels. Methods Forty weight age malched Wistar rats were randomly divided into normal control group (normal group), the CIA model group (CIA group), ozone (O 3 group), and methotrexate (MTX group). In addition to the normal control group, Freund's complete adjuvant and bovine type Ⅱ collagen were injected to establish the rat model of CIA. After the model was sucessfully developed, double ankle injection concentration ozone group of 40 μg/ml of O3 each 1 ml, 1 times a week, a total of injection for 3 weeks for the experimenal group. MTX group of 0.9 mg/kg was injected 1 times a week for 3 weeks for the MTX group. Degree of foot swelling was measured, and radiographic assessment of arthritis index (AI) score was performed. One week after treatment, angular vein blood was collected for the rats after the intervention, flow multi-factor detection technology was used to test each rat. T test or Wilcoxon rank test was used to compare the difference between groups. Results ① After 3 week administration with O3, dcgree of foot swelling, and AI of the O3 group was reduced significanly than the CIA group during the same period (foot swelling degree: O3 group: (4.21±0.14) ml, CIA group (9.12±0.17) ml, T=64.08, P=0.00; AI O3 group: [(2.97± 0.18) ml, CIA group: 5.76 ±0.13, T=37.24, P=0.00], and X-ray showed joint damage was alleviated. ② The serum level of RANKL in the CIA group was significantly higher than of the normal group [CIA model group 1890.70(797.03, 10571.94)], normal group [74.46(29.21, 95.37), T=43, P=0.005] during the same period; The serum level of RANKL in the O3 group was significantly lower than the CIA group [O3 group 28.09 (14.11, 207.30), CIA group 1890.70 (797.03, 10571.94), T=39, P0.05).③Serum RANKL/OPG of the CIA group was significantly higher than that of the normal group during this period, the difference was statistically significant [CIA group 250.68(42.33, 2959.78), normal group 4.32(3.16,5.30), T=36, P0.05). Conclusion Intra-articular injection of concentration of 40 μg/ml of O3 can reduce RA rat joint swelling degree, which may relate to the mechanism that O3 can lower levels of serum RANKL and RANKL/OPG ratio, reduce osteoclast formation and activation.

Regulation of mRNA expression of OPG and RANKL in hPDLCs by hypoxia in vitro / 重庆医学

Objective To study the effect of hypoxia on the mRNA expression of osteoprotegerin(OPG) and receptor activa‐tor for nuclear factor‐κB ligand(RANKL) in human periodontal ligament cells(hPDLCs) and to explore the role of hypoxia in the orthodontic bone resorption in pressure side .Methods The primary hPDLCs were cultivated with enzyme digestion assay and tis‐sue cultivation .The 3-5 generations of hPDLCs were respectively cultured 3 ,6 ,12 and 24 h in normoxia condition (20% O2 ) or in hypoxia condition (2% O2 ) .The mRNA expression of OPG and RANKL were detected with RT‐PCR .The experimental data was analyzed by one way ANOVA using SPSS15 .0 .Results After cultivated in hypoxia condition for 3 h or 6 h ,the mRNA expression of OPG and RANKL in hPDLCs didn′t change significant(P> 0 .05) .After cultivated in hypoxia condition for 12 h or 24 h ,the mRNA expression of OPG in hPDLCs decreased while the RANKL increased .Thus the ratio of RANKL/OPG increased and the difference was significant(P<0 .05) .Conclusion Hypoxia can regulate the mRNA expression of OPG and RANKL in hPDLCs and will promote the orthodontic bone resorption in pressure side .

Improved induction culture system for Raw264.7 cells to differentiate into osteoclasts / 吉林大学学报(医学版)

Objective To establish a high-performance induction culture system for Raw264.7 cells to differentiate into osteoclasts(OC)invitro by improving the cell culture program.Methods The Raw264.7 cells were cultured withα-MEM medium containing 50 μg · L-1 M-CSF, 100 μg · L-1 RANKL, and 1 × 10-8 mol · L-1 1α,25-(OH)2 D3 in 5% CO2 for 12 d at 37℃. The cells were digested transiently every time before the medium was changed after every three days. The morphologic changes of the Raw264.7 cells were observed by inverted microscope.The maturation and phagotrophic function of OC were identified by HE,TRAP,FITC-phalloidin staining and immunofluorescence.Results The cells remained to grow in single layers all the time in most areas of the well during the whole induction by the improved culture program. The observation results of inverted microscope and HE staining showed that the growth area of the polykaryotic OC reached to 70% of the well on day 1 2. FITC-phalloidin staining showed that in the maturation of the OC, the cluster-shaped podosomes in the pseudopodia gradually transformed into rings,which finally fused to form a large belt surrounding the periphery of the cytoplasm. The calcitionin receptor (CTR) expressed by OC was markedly enhanced compared with the precursor cells by immunofluroescence staining,and a large number of red granules appeared in the cytoplasm of OC with TRAP staining on day 1 2. These results comfirmed that the obtained OC were maturated and owned phagotrophic function. Conclusion A high-performance induction culture system for Raw264. 7 cells to differentiate into OC in vitro induced by combination of 50μg · L-1 M-CSF, 100 μg · L-1 RANKL,and 1 × 10-8 mol·L-1 1α,25-(OH)2 D3 is established by improving the cell culture program.

The relationship between single-nucleotide polymorphism in RANKL, osteoprotegerin gene and rheumatoid arthritis / 中华风湿病学杂志

Objective To investigate the relationship between single-nucleotide polymorphism (SNP)in receptor activator for nuclear factor-κB ligand (RANKL),osteoprotegerin (OPG) gene and rheumatoid arthritis (RA).Methods In our study,3 SNPs in the genes of OPG (2 SNP:rs2073618,rs3102735) and RANKL (1 SNP:rs2277438) by ligase detection reactions from 200 RA and 201 controls were examined.BMD values of different areas were assessed using dual-energy X-ray absorptiometry.Clinical and laboratory parameters were collected.Analysis of variance,t-test and x2 test were used for statistical analysis.Results No signi-ficant differences in the distribution of the alleles and genotypes were observed between case group and the control group (P＞0.05).The haplotype analysis for RANKL and OPG SNPs showed that the rs2073618/rs2277438/rs3102735 GGG haplotype could reduce the risk of RA (1.5％ vs 6.0％,P=0.008; OR 0.216;95％CI:0.081 to 0.575) and the GAG haplotype increased the risk of RA (14.5％ vs 8.4％,P=0.007; OR 1.862,95％CI:1.179 to 2.943).Patients with RANKL-rs2277438 AA or GG genotypes (n=6) had significantly higher BMD values compared to those with AG genotypes (n=39) at spine lumber 3 (1.05±0.22 vs 0.93±0.26,t=2.314,P=0.023),spine lumber 4 (1.06±0.24 vs 0.94±0.28,t=2.27,P=0.030),spine lumber 2-4 (1.04±0.21 vs 0.89±0.28,t=2.788,P=0.007).The tender joint counts (13±7 vs 10±6),tender joint index (19±11 vs 13±9),and VAS score (5.7±1.9 vs 4.8±1.8) differed significantly between patients with the OPG-rs2073618 CC or GG genotypes (n=60) and GC genotypes (n=40).Conclusion The rs2073618/rs2277438/rs3102735GGG haplotype may be protective against RA,while GAG haplotype may increase the susceptibility to RA.RANKL gene SNP rs2277438 may affect BMD value at spine lumber,and OPG gene SNP rs2073618 may influence the disease activity of RA patients.