Research progress on invasive cervical resorption / 口腔疾病防治

@#Tooth absorption can be divided into physiological absorption and pathological absorption. Root absorption of mature deciduous teeth is physiological absorption. Pathological absorption includes internal absorption and external absorption. Internal absorption, also known as intramedullary absorption, includes inflammatory absorption and alternative absorption. External tooth absorption originates from the outer surface of the root or the neck of the tooth and can be divided into inflammatory absorption, alternative absorption, pressure resorption and invasive cervical resorption. Invasive cervical resorption (ICR) is pathological damage caused by many factors, which usually begins in the cemento-enamel junction and extends peripherally or horizontally in the dentin. It hardly invades the pulp. Orthodontic devices, trauma, bleaching, systemic diseases, and the use of certain medications can all lead to invasive cervical resorption. The clinical manifestations of ICR are usually asymptomatic or not obvious, and most of which are found in imaging examinations. Because caries and internal absorption are often misdiagnosed through plain apical radiography, cone beam computed tomography (CBCT) can help to better understand the situation of invasive cervical resorption. Because the pathogenesis and etiology of invasive cervical resorption are not fully understood, clinical negligence and inadequate treatment of invasive cervical resorption can even cause unnecessary tooth loss. This article reviews the latest research progress on the histopathologic features, pathogenic mechanism, susceptibility factors, diagnosis and treatment of ICR, with special emphasis on susceptibility factors and their mechanisms.

Research progress on ankylosis of primary molars / 口腔疾病防治

@#Ankylosis of primary molars is a kind of eruption abnormality of the teeth, where the periodontal membrane disappears, owing to a bony union between bone and root. Studies have shown that the common proportion of ankylosed primary molars is 1.3%~8.9% with an equal occurrence. In the primary dentition, the mandibular first primary molar is the most commonly affected tooth, while in the middle mixed dentition stage of development, the second primary molar is more affected. Its etiology may be related to genetics, signaling pathways of mineralization metabolism of local alveolar bone or cementum, cytokines secreted by epithelial rest cells of Malassez, and enhanced inflammatory reactions during physiological absorption of roots. Ankylosis of primary molars can be diagnosed by clinical symptoms and imaging and is classified as mild, moderate and severe according to the degree of infraocclusion. As it may cause a series of complications, such as occlusal disturbances, delayed exfoliation and incomplete alveolar process development, multidisciplinary treatment, including in the departments of pediatric dentistry, orthodontics, periodontics and prosthodontics, should be adopted, and long-term treatment is determined based on the patient's age, severity of infraocclusion, and presence of permanent teeth. This review summarizes the etiology, diagnosis, complications and treatment of ankylosed primary molars to provide a reference for the clinical diagnosis and treatment of decidual molar fixation.

Study on the role and mechanism of osteogenesis induced by advanced platelet-rich fibrin and β-tricalcium phosphate complex / 口腔疾病防治

Objective @#To investigate the role and mechanism of bone formation caused by the ratio of advanced platelet-rich fibrin (A-PRF) and β-tricalcium phosphate (β-TCP) in rabbit femur defect model, which provides a new idea for clinical treatment of bone defect.@*Methods @#Twenty-four New Zealand white rabbits were divided into model group, 1∶1 complex group (A-PRF∶β-TCP=1∶1), 2∶1 complex group (A-PRF∶β- TCP=2∶1) and 4∶1 complex group (A-PRF∶β- TCP=4∶1）, with 6 rabbits in each group. Femoral defect models were constructed in each group. In the composite group, the bone defect was filled with composite material, while in the model group, no material was filled. After 8 weeks, the animals were euthanized and specimens were collected. Bone mineral density (BMD), bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.SP) and trabecular number (Tb.N) in femoral defect tissue were measured by micro-CT and photographed. Hematoxylin - eosin staining was used to detect the pathological changes of new bone tissue. The morphological changes of the new bone tissue were observed by scanning electron microscopy. Determination of phospho-mitogen activated protein kinase p38 (p-p38MAPK), CCAAT/enhancer binding protein homologous protein (CHOP) and phospho-cysteine aspartic protease-3 (p-Caspase3) in newborn femur by ELISA. The mRNA expressions of osteoprotegerin (OPG), bone morphogenetic protein-2 (BMP-2), receptor activator of nuclear factor kappa-B ligand (RANKL) and p38MAPK were detected by real-time quantitative PCR. The expression of OPG, BMP-2, RANKL, p-p38MAPK and p-Caspase3 protein in the new bone tissue was observed by immunohistochemistry. @*Results @#In the model group, bone formation in the femoral defect area was slow and osteogenic quality was poor. Compared with the model group, the bone formation and neocapillaries of femoral defect area in the complex group was good, BMD, BV.TV, Tb.Th, Tb.N were increased, and Tb.Sp were decreased, the expressions of p-p38MAPK, CHOP and p-Caspase3 were decreased, and the mRNA and protein expressions of OPG and BMP-2 were increased. The mRNA expression of RANKL and p38MAPK was decreased. Apoptosis in new bone tissue of each group showed the lowest apoptosis rate in samples of the 2∶1 complex group (P<0.05); A-PRF: β-TCP=2∶1 ratio has the best osteogenic effect. @*Conclusion@#The complex composed of A-PRF and β-TCP can promote the expression of OPG, inhibit the expression of RANKL and phosphorylation of p38MAPK, reduce the apoptosis of new bone tissue cells, and promote osteogenic differentiation.

Research progress on the relationship between IL-37 and periodontitis / 口腔疾病防治

@#Periodontitis is the inflammation of periodontal tissue caused by dental plaque, which absorbs the alveolar bone and cementum. The immune response triggered by CD4+T cells is the key factor for the aggravation of periodontitis. The activation of dendritic cells and the receptor activator of the NF-κB ligand (RANKL) pathway is an important link in the alveolar bone resorption of periodontal tissue. Pro-inflammatory factors such as interferon-γ (IFN-γ), tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) also play important roles in the development of periodontitis. Interleukin-37(IL-37), which is a newly discovered cytokine in the IL-1 family, has five shear variants from a to e, among which the clover β-structure encoded by exon 4 plays an important role in the binding of cytokines and the corresponding receptors. IL-37 has strong anti-inflammatory and inhibition of autoimmunity, can enter the nucleus with the help of caspase-1 and bind with Smad proteins to regulate the transcription of pro-inflammatory genes. Extracellular IL-37 can bind to IL-18 binding protein and inhibit the production of pro-inflammatory factors. IL-37 can inhibit the progression of periodontitis by inhibiting the RANKL signaling pathway, inhibiting the proliferation and differentiation of dendritic cells and CD4+T cells, binding to Smad proteins, and releasing pro-inflammatory factors such as IFN-γ and TNF-α. The IL-37 concentration in periodontal tissue can indicate the progression of periodontitis. Few studies have described the interaction between the anti-inflammatory factor IL-37 and periodontitis. Thus, in this paper, the structure and function of IL-37 and the related factors between IL-37 and periodontitis will be reviewed.

Effect of Decomposed Zuoguiwan Recipes in Improving BMD of Ovariectomized Rats by Regulating OPG/RANKL Pathway Mediated by β2AR / 中国实验方剂学杂志

Objective:To investigate the mechanism of decomposed Zuoguiwan（ZGW） recipes in treating ovariectomized osteoporosis rats. Method:Forty Sprague-Dawley female rats were equally and randomly divided into Sham-operated group, ovariectomized model group, positive group, and low and high-dose ZGW groups. After 12 weeks of administration by gavage, the bone mineral density (BMD) of rats' distal femur was measured by micro-CT, the morphology of bone tissue were observed by hematoxylin-eosin staining (HE), β-cross-linked c-telopeptide of type Ι collagen (β-CTX) and bone-specific alkaline phosphatase (BALP) in serum were detected by enzyme-linked immunosorbent assay (ELISA), and the mRNA and protein expressions of β2AR, OPG and RANKL were evaluated by Western blot analysis and real-time quantitative polymerase chain reaction （PCR）. Result:Compared with Sham-operated group, BMD of rats in ovariectomized model group was decreased (P<0.01), morphology of bone tissue was destroyed, serum BALP was reduced, while β-CTX was boosted (P<0.01)，mRNA and protein expressions of OPG in tibia were reduced, while RANKL were increased, and mRNA and protein expressions of β2AR in the hypothalamus were decreased (P<0.05, P<0.01). Compared with ovariectomized model group, BMDs of rats in low and high-dose ZGW groups were increased (P<0.01), morphology of bone tissue was repaired, serum BALP and mRNA and protein expressions of OPG in tibia were up-regulated (P<0.05, P<0.01), whereas serum β-CTX and mRNA and protein expressions of β2AR in the hypothalamus and RANKL in tibia were down-regulated (P<0.05, P<0.01). Conclusion:Yang-nourishing components in decomposed Zuoguiwan recipes can improve BMD of ovariectomized rats by regulating OPG/RANKL pathway mediated by β2AR. "Seeking Yin in Yang" is a crucial mechanism of Zuoguiwan in treating ovariectomized osteoporosis in rats.

The role of B cell osteoimmunity in periodontitis / 口腔疾病防治

@#As the most important pathological feature of periodontitis, alveolar bone resorption also results in tooth loss and oral dysfunction. According to recent research, the host immune response is the major factor leading to alveolar bone resorption. Antibodies, immune cells and inflammatory cytokines involved in this procedure cause an imbalance of bone formation and destruction, which is called osteoimmunity. Given the importance of adaptive humoral immunity during periodontitis, B cells are considered crucial in the development of periodontitis. Therefore, establishing B cell osteoimmunity is an effective way for us to deeply assess the start, development and prognosis of periodontitis. It has been proven that the development process of B cells is accompanied by changes in bone density or morphology. We have reviewed previous literature to understand the role of B cell bone immunity in the pathological process of periodontitis, and the results showed that B cells regulate the development of bone cell lines through transcription factors (such as RANKL, PU.1, E2A, etc.). In addition, various cytokines expressed by B cells (such as IFN-γ, IL-17, IL-10, TGF-β, etc.) can participate in the regulation of bone cells.

Effect of enhanced masticatory force on OPG, RANKL and MGF in alveolar bone of ovariectomized rats

Abstract Menopause induces oral bone loss, leading to various oral diseases. Mastication importantly affects bone metabolism in the jawbone. Objective: To analyze the effect of enhanced masticatory force on osteoprotegerin (OPG), receptor activator of nuclear factor kappa B ligand (RANKL), and mechano-growth factor (MGF) in alveolar bone of ovariectomized rats and to study the mechanics mechanism of the alveolar bone of ovariectomized rats response to enhanced masticatory force. Methodology: Thirty Sprague Dawley rats were randomly divided into three groups: sham-operation group (fat around the removed ovary + normal hard diet), model group (ovariectomy + normal hard diet), and experimental group (ovariectomy + high hard diet). It was a 2-month experiment. Enzyme-linked immunosorbent assay (ELISA) detected serum estradiol (E2), osteocalcin (BGP) and alkaline phosphatase (ALP) in rats. Bone histomorphometric indices in the third molar region of maxilla were detected by micro-CT; protein expressions of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Western blot; and gene expression of OPG, RANKL, and MGF in the third molar region of maxilla was detected by Quantitative Real-Time PCR. Results: Comparing with model group, serum E2 in experimental group increased but not significantly, serum BGP and serum ALP in experimental group decreased but not significantly, OPG in experimental group in alveolar bone increased significantly, RANKL in experimental group in alveolar bone decreased significantly, RANKL/OPG ratio in experimental group decreased significantly, MGF in experimental group in alveolar bone increased significantly, bone volume to total volume fraction increased significantly in experimental group, trabecular thickness increased significantly in experimental group, and trabecular separation decreased significantly in experimental group. Conclusion: Enhanced masticatory force affected the expression of OPG, RANKL, and MGF in alveolar bone of ovariectomized rats, improved the quality of jaw bone of ovariectomized rats, and delayed oral bone loss by ovariectomy.

East java extract propolis as potential intracanal medicament in experimentally induced chronic apical periodontitis

Introduction: A persistent infection after cleaning and shaping root canal is the main etiology of root canal treatment failure. Enterococcus faecalis has been considered as one of the most resistant species in root canal treatment. E. faecalis can stimulate receptor activator of nuclear factor-kappa B ligand (RANKL) which can increase nuclear factor of activated T-cell (NFATc1) in chronic apical periodontitis. East Java propolis has antibacterial effects and is biocompatible with in vitro effects. Aim: This study is aimed to analyze the East Java propolis extract as potential intracanal medicament in chronic apical periodontitis caused by E. faecalis bacterial infection. Materials and Methods: This study used 30 Wistar rats divided into three groups. In Group I, the first upper right molar tooth as healthy tooth was used for negative control group. In Group II, the first upper right molar tooth was used for a prepared root canal, and 10 ml brain heart infusion broth containing E. faecalis ATCC29212 106 CFU was injected into the canal and restored with glass-ionomer cement (GIC) for the experimentally induced chronic apical periodontitis group. In Group III, after root canal preparation, E. faecalis ATCC 29212 106 CFU was injected, and then, 10 μl propolis applied and tooth restored with GIC. It took 21 days for the periapical lesions to develop after pulp infection. The rats were then sacrificed to conduct immunohistochemical examinations in order to measure the expressions of RANKL and NFATc1. Results: The average of RANKL and NFATc1 expression in Group III was significantly lower than those in the experimentally induced chronic apical periodontitis group (P < 0.05). Conclusion: It can be concluded that East Java propolis extract is a potential intracanal medicament through the study of experimentally induced chronic apical periodontitis caused by E. faecalis infection in Wistar rats.

Effect of Vitamin D during Orthodontic Tooth Movement on Receptor Activator of Nuclear Factor Kappa-Β Ligand Expression and Osteoclast Number in Pregnant Wistar Rat (Rattus novergicus)

Background: Female patients have the possibility tobecome pregnant during orthodontic treatment. VitaminD usually consumed by pregnant women. Estrogen andVitamin D could affect bone metabolism. Aim andObjectives: The aim of this study was to analyze theeffect of vitamin D during orthodontic movement inpregnant rats by Receptor Activator of Nuclear FactorKappa-Β Ligand (RANKL) expression and osteoclastnumber. Material and Methods: The experimentalobservational analytic study with post-test only controlgroup design and simple random sampling method wasconducted. 24-healthy-female Wistar rats were dividedinto 4 groups; K1: pregnant rats with orthodontic toothmovement and vitamin D on Day 7; K2: pregnant ratswith orthodontic tooth movement and vitamin D on Day14; K3: pregnant rats with orthodontic tooth movementwithout vitamin D on Day 7 and; K4: pregnant rats withorthodontic tooth movement without vitamin D on Day214. Nickle-Titanium coil spring with 10 g/mm forcewas placed between the incisors and the maxillarymolars. The RANKL expression and osteoclastsnumber were analyzed using Analysis of Variance(ANOVA) (p<0.05). Results: The highest osteoclastsnumber (8.494 ± 1.194), and RANKLexpression (7.967± 2.185) found in K1 group with significant betweengroups (p<0.05).Conclusions: Vitamin D increaseosteoclast number and RANKL expression duringorthodontic tooth movement in pregnant rats.

Efficacy of Wenyangbushen Formula on mRNA Expression of Osteoprotegerin, Receptor Activator of Nuclear Factor-kappa B and Its Ligand in Rabbits with Steroid-induced Avascular Necrosis of Femoral Head / 中国康复理论与实践

Objective:To observe the effect of Wenyangbushen formula on mRNA expression of osteoprotegerin (OPG), receptor activator of nuclear factor- kappa B (RANK) and receptor activator of nuclear factor- kappa B ligand (RANKL) in rabbits with steroid-induced avascular necrosis of femoral head (SANFH). Methods:A total of 46 healthy conventional New Zealand white rabbits were randomly divided into normal group (n = 10) and model building group (n = 36). The modified method of horse serum plus methylprednisolone was used to establish the SANFH model. Two rabbits from the normal group and four from the model building group were used for HE staining. Then the other models were randomly divided into model group, and low-dose, medium-dose and high-dose treatment groups, with eight rabbits in each group. The normal group was given normal saline 10 ml/d, and the treatment groups were given Wenyangbushen formula 6.44 g/(kg·d), 9.66 g/(kg·d) and 12.88 g/(kg·d), respectively, for eight weeks. The mRNA expression of OPG, RANK and RANKL was detected by reverse transcription- polymerase chain reaction. Results:The empty lacuna rate was significantly higher in the model group than in the normal group (t = 17.085, P < 0.001). Compared with the model group, the mRNA expression of OPG increased (P < 0.01), and the mRNA expression of RANK and RANKL decreased (P < 0.01), in the treatment groups. Compared with the low-dose treatment group, the mRNA expression of OPG increased (P < 0.01), and the mRNA expression of RANK and RANKL decreased (P < 0.01), in the medium-dose and high-dose treatment groups. There was no significant difference in the mRNA expression of OPG, RANK and RANKL between the low-dose treatment group and the high-dose treatment group (P > 0.05). Conclusion:Wenyangbushen formula could increase the mRNA expression of OPG and inhibit the mRNA expression of RANK and RANKL in the femoral head tissue of the rabbits with SANFH.

Effect of Tripterygium glycosides combined with Recombinant human tumor necrosis factor receptorⅡ antibody fusion protein for injection on serum vascular endothelial growth factor, rheumatoid factor, receptor activator of nuclear factor κ B ligand levels in patients with rheumatoid arthritis / 中国综合临床

Objective To investigate the effect of tripterygium glycosides combined with recombinant human tumor necrosis factor receptor Ⅱ antibody fusion protein for injection on serum vascular endothelial growth factor (VEGF),rheumatoid factor (RF),receptor activator of nuclear factor κ B ligand (RANKL) levels in patients with rheumatoid arthritis.To provide reference for rational clinical application.Methods From December 2014 to January 2016,132 patients with rheumatoid arthritis were divided into observation group and control group by random number table method,,with 66 cases in each group,The control group was treated with tripterygium glycosides alone (10 mg each time,3 times daily,orally) for 3 months.The observation group was treated with a combination of tripterygium glycosides and recombinant human tumor necrosis factor receptor Ⅱ (0.4 mg/kg,once weekly,hypodermic injection) for 3 months.The clinical efficacy,and serum VEGF,RF and RANKL levels were compared between 2 groups.Results The effective rate of the observation group was 92.4％ (61/66),which was significantly higher than that in the control group (80.3％,53/66).There was a significant difference between the two groups (x2=4.117,P＜0.05).There was no significant difference in the levels of serum VEGF,RF and RANKL between the two groups (t =0.174,0.103,0.359,all P＞0.05).After treatment,the levels of serum VEGF,RF and RANKL in the observation group and the control group were (20.8± 11.5) ng/L and (27.3 ±13.1) ng/L,(258.4±54.5) U/L and (298.1 ±49.5) U/L,(0.083±0.021) pmol/L and (0.197 ± ±0.064),respectively.There were significant differences between the two groups (t =3.029,4.381,13.750,all P＜0.05).The incidence rate of adverse reactions in the control group was 10.5％ (7/66),which was significantly higher than that in the observation group (1.5％,1/66).There was a significant difference between the two groups(x2 =4.790,P＜0.05).The one-year recurrence rate was 25.0％ (13/52) in the control group and that was 6.7％ (4/60) in the observation group,respectively,and there was a significant difference between the two groups (x2 =7.272,P＜ 0.05).Conclusion Tripterygium glycosidescombined with recombinant human tumor necrosis factor receptor Ⅱ antibody fusion protein for injection is effective in the treatment of rheumatoid arthritis,which reduces the levels of serum VEGF,RF and RANKL,and has a low incidence of adverse reactions and recurrence.

Effect of Zuoguiwan in Improving BMD and Trabecular Bone Microarchitecture in Ovariectomy-induced Osteoporosis Rats by Regulating RANKL/OPG Pathway Mediated by β2AR / 中国实验方剂学杂志

Objective: To investigate the mechanism of Zuoguiwan in treating ovariectomy-induced osteoporosis rats by receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) signaling pathway mediated by β2-adrenergic receptor (β2AR). Method: Forty Sprague-Dawley female rats were randomly divided into Sham-operated group (Sham) and four ovariectomized (OVX) subgroups. Rats in Sham and OVX groups were treated with 17β-estradiol (50 μg·kg-1·d-1), and low and high-dose ZGW (2.3,4.6 g·kg-1 lyophilized powder) for 3 months, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum markers of bone turnover. Micro-CT was used to evaluate and measure trabecular bone microarchitecture and bone mineral density (BMD) of the right distal femur. Western blot analysis and Real-time PCR were used to measure mRNA and protein expressions of β2AR, OPG and RANKL. Result: After 12 weeks of treatment with Zuoguiwan, the level of serum β-cross-linked c-telopeptide of type Ι collagen (β-CTX) (PPPβ2AR in the hypothalamus (PPConclusion: The mechanism of Zuoguiwan in alleviating BMD and trabecular bone microarchitecture in ovariectomy-induced osteoporosis rats might be related to the regulation of RANKL/OPG Pathway mediated by β2AR.

Effect of risperidone on proliferation and apoptosis of MC3T3-E1 cells

This aim of this study was to assess the molecular mechanism of osteoporosis in schizophrenia patients with risperidone use. Here, we investigated the effects of risperidone on cellular proliferation and apoptosis of a preosteoblast cell line, MC3T3-E1. Cell viability and apoptotic rate of MC3T3-E1 were detected by cell counting kit-8 and flow cytometry at a serial dose of risperidone and at different time points, respectively. Bone transformation relevant gene serum osteocalcin (BGP), collagen 1, tumor necrosis factor-α (TNF-α), osteoprotegerin (OPG), and receptor activator of nuclear factor-κB ligand (RANKL) mRNA levels were determined by real-time PCR (qPCR). Their protein expression patterns were evaluated using western blot. The results revealed that risperidone dramatically inhibited MC3T3-E1 cell proliferation in a dose-dependent manner. It also significantly induced MC3T3-E1 cell apoptosis. TNF-α gene and protein levels were greatly enhanced after risperidone treatment. In contrast, BGP, collagen 1, OPG, and RANKL gene and protein levels were markedly downregulated. Our study indicated that risperidone suppressed MC3T3-E1 cell proliferation and induced apoptosis. It also regulated BGP gene and protein expression.

Bone-targeted therapies to reduce skeletal morbidity in prostate cancer / 亚洲男科学杂志(英文版)

Bone metastases are the main driver of morbidity and mortality in advanced prostate cancer. Targeting the bone microenvironment, a key player in the pathogenesis of bone metastasis, has become one of the mainstays of therapy in men with advanced prostate cancer. This review will evaluate the data supporting the use of bone-targeted therapy, including (1) bisphosphonates such as zoledronic acid, which directly target osteoclasts, (2) denosumab, a receptor activator of nuclear factor-kappa B (RANK) ligand inhibitor, which targets a key component of bone stromal interaction, and (3) radium-223, an alpha-emitting calcium mimetic, which hones to the metabolically active areas of osteoblastic metastasis and induces double-strand breaks in the DNA. Denosumab has shown enhanced delay in skeletal-related events compared to zoledronic acid in patients with metastatic castration-resistant prostate cancer (mCRPC). Data are mixed with regard to pain control as a primary measure of efficacy. New data call into question dosing frequency, with quarterly dosing strategy potentially achieving similar effect compared to monthly dosing for zoledronic acid. In the case of radium-223, there are data for both pain palliation and improved overall survival in mCRPC. Further studies are needed to optimize timing and combination strategies for bone-targeted therapies. Ongoing studies will explore the impact of combining bone-targeted therapy with investigational therapeutic agents such as immunotherapy, for advanced prostate cancer. Future studies should strive to develop biomarkers of response, in order to improve efficacy and cost-effectiveness of these agents.

Expression of osteoprotegerin and receptor activator of nuclear factor kappa-B ligand in mandibular ramus osteotomy healing with administration of different doses of parathyroid hormone / 中华口腔医学杂志

Objective@#To investigate the effect of parathyroid hormone (PTH) on the bone healing of mandibular ramus osteotomy.@*Methods@#The mandibular ramus osteotomy model was established in sixty rabbits and these rabbits were randomly divided into experimental group A, experimental group B and control group. In the experimental group A and experimental group B, the rabbits were given PTH (20 and 40 μg/kg respectively) every other day after operation. In the control group, 1 ml saline was given. The animals were sacrificed at 1 week, 2 weeks, 3 weeks and 4 weeks postoperatively. The new bone formation was observed by histology and cone bone CT. The expression of osteoprotegerin and receptor activator of nuclear factor kappa-B (RANKL) in the new bone was detected by real-time quantitative PCR.@*Results@#The experimental groups has better osteogenesis and the bone mineral density than the control group in osteotomy area. The experimental group B showed the best osteogenesis.Osteoprotegerin mRNA expression in experimental group A (1.127±0.035, 1.742±0.049, 1.049±0.062, 1.063±0.036) was significantly higher than that in the control group in each period (0.965±0.082, 1.254±0.071, 0.793±0.061, 0.684±0.055) (P=0.010, P=0.000, P=0.001, P=0.020), while group B (1.416±0.205, 2.648±0.168, 1.652±0.091, 1.712±0.070) was significantly higher than group A (P=0.000, P=0.010, P=0.023, P=0.003). RANKL mRNA expression in control group (1.666±0.086, 1.058±0.105, 0.885±0.124, 0.972±0.136) was significantly higher than that of the group A (0.788±0.036, 0.585±0.017, 0.692±0.017, 0.527±0.051) (P=0.001, P=0.006, P=0.003, P=0.028) in each period, while group A was significantly higher than group B(0.247±0.022, 0.240±0.034, 0.134±0.011, 0.103±0.050) (P=0.000, P=0.001, P=0.002, P=0.012).@*Conclusions@#PTH can upregulate the expression of osteoprotegerin and reduce expression of RANKL, thus promoting new bone formation. Intermittent administration of high dose of parathyroid hormone can further promote the healing process after mandibular ramus osteotomy.

A novel effect of geraniin on OPG/RANKL signaling in osteoblasts

In this study, the effects of geraniin on osteoprotegerin/receptor activator of nuclear factor-κB ligand(OPG/RANKL) in regulating the proliferation of osteoblasts and suppression of osteoclast-like cells (OLC) in OLC-osteoblast co-cultured system in vitro were investigated. Osteoblasts were cultured and identified with alkaline phosphatase (ALP), gomori stain, and mineralized nodule stain. OLCs were isolated from long bones of Sprague-Dawley (SD) rats and identified with tartrate-resistant acid phosphatase(TRAP) stain. Methyl thiazolyl tetrazolium assay was used to examine the proliferation of osteoblasts, and immunocytochemistry and in situ hybridization to analyze the expression OPG/RANKL in osteoblasts co-cultured with osteoclasts under the action of geraniin, respectively. Geraniin could regulate the proliferation of osteoblasts MC3T3-E1, decrease the number of OLC in OLC-osteoblast co-cultured system, and inhibit the bone resorption areas and resorption pits of OLC in vitro experiments. Geraniin could promote the mRNA and protein expression levels of OPG and suppress those of RANKL in osteoblasts. These results indicate that geraniin has a promoting effect on the proliferation of osteoblasts and an inhibitory effect on the osteoclastic bone-resorption through regulating OPG/RANKL signaling pathway in OLC-OB co-cultured system.

The effects of different concentrations of crocin on receptor activator of nuclear factor kappa B ligand(RANKL)–induced osteoclastogenesis / 天津医药

Objective To investigate the effects of different concentrations of crocin on receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclastogenesis using the monocyte-macrophage cell line RAW264.7. Methods The monocyte-macrophage cell line RAW264.7 was cultured routinely.After treatment with 0,6.25,12.5,25, 50,100,200 and 400 μmol/L crocin,cell counting kit-8(CCK-8)assay was used to analyze the viability of RAW264.7 cells to screen out the appropriate experimental concentration. RAW264.7 cells were induced by RANKL (100 ng/L) to form osteoclasts. After treated with 0, 12.5, 50 and 100 μmol/L crocin respectively, the number of osteolasts was counted by tatrate resistant acid phosphatasec (TRAP) staining. Real-time PCR was used to detect the mRNA expression levels of calcitonin receptor(CTR),nuclear factor of active T cells 1(NFATC1),C-fos and TRAP.Results No significant effects of crocin (within 0-100 μmol/L) were found on the viability of RAW264.7 cells (P>0.05). However, When crocin concentration was over 100 μmol/L,the cell proliferation was decreased,and which showed a significant inhibitory effect on proliferation (P<0.05). Thus, 0-100 μmol/L crocin was selected as the experiment concentration. The amount of differentiated osteolasts and the expression levels of CTR,NFATC1,C-fos and TRAP mRNA were decreased significantly with the increased concentrations of crocin(P<0.05).Conclusion At a certain concentration(0-100 μmol/L),the higher levels of crocin could inhibit RANKL-induced osteoclastogenesis.

Effect of caspases and RANKL induced by heavy force in orthodontic root resorption / 대한치과교정학회지

OBJECTIVE: Orthodontic root resorption (ORR) due to orthodontic tooth movement is a difficult treatment-related adverse event. Caspases are important effector molecules for apoptosis. At present, little is known about the mechanisms underlying ORR and apoptosis in the cementum. The aim of the present in vivo study was to investigate the expression of tartrate-resistant acid phosphatase (TRAP), caspase 3, caspase 8, and receptor activator of nuclear factor kappa-B ligand (RANKL) in the cementum in response to a heavy or an optimum orthodontic force. METHODS: The maxillary molars of male Wistar rats were subjected to an orthodontic force of 10 g or 50 g using a closed coil spring. The rats were sacrificed each experimental period on days 1, 3, 5, and 7 after orthodontic force application. And the rats were subjected to histopathological and immunohistochemical analyses. RESULTS: On day 7 for the 50-g group, hematoxylin and eosin staining revealed numerous root resorption lacunae with odontoclasts on the root, while immunohistochemistry showed increased TRAP- and RANKL-positive cells. Caspase 3- and caspase 8-positive cells were increased on the cementum surfaces in the 50-g group on days 3 and 5. Moreover, the number of caspase 3- and caspase 8-positive cells and RANKL-positive cells was significantly higher in the 50-g group than in the 10-g group. CONCLUSIONS: In our rat model, ORR occurred after apoptosis was induced in the cementum by a heavy orthodontic force. These findings suggest that apoptosis of cementoblasts is involved in ORR.

Bone-targeted therapies to reduce skeletal morbidity in prostate cancer / 亚洲男科学杂志(英文版)

Bone metastases are the main driver of morbidity and mortality in advanced prostate cancer. Targeting the bone microenvironment, a key player in the pathogenesis of bone metastasis, has become one of the mainstays of therapy in men with advanced prostate cancer. This review will evaluate the data supporting the use of bone-targeted therapy, including (1) bisphosphonates such as zoledronic acid, which directly target osteoclasts, (2) denosumab, a receptor activator of nuclear factor-kappa B (RANK) ligand inhibitor, which targets a key component of bone stromal interaction, and (3) radium-223, an alpha-emitting calcium mimetic, which hones to the metabolically active areas of osteoblastic metastasis and induces double-strand breaks in the DNA. Denosumab has shown enhanced delay in skeletal-related events compared to zoledronic acid in patients with metastatic castration-resistant prostate cancer (mCRPC). Data are mixed with regard to pain control as a primary measure of efficacy. New data call into question dosing frequency, with quarterly dosing strategy potentially achieving similar effect compared to monthly dosing for zoledronic acid. In the case of radium-223, there are data for both pain palliation and improved overall survival in mCRPC. Further studies are needed to optimize timing and combination strategies for bone-targeted therapies. Ongoing studies will explore the impact of combining bone-targeted therapy with investigational therapeutic agents such as immunotherapy, for advanced prostate cancer. Future studies should strive to develop biomarkers of response, in order to improve efficacy and cost-effectiveness of these agents.

Effect of Wenhua Juanbi Recipe () on expression of receptor activator of nuclear factor kappa B ligand, osteoprotegerin, and tumor necrosis factor receptor superfamily member 14 in rats with collagen-induced arthritis / 中国结合医学杂志

<p><b>OBJECTIVES</b>To study the effect of Wenhua Juanbi Recipe (, WJR) on expression of receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG), and tumor necrosis factor receptor superfamily member 14 (TNFRSF14, also known as LIGHT) in rats with collagen-induced arthritis (CIA).</p><p><b>METHODS</b>CIA rats were generated by subcutaneous injection of bovine collagen type-II at the tail base. Sixty CIA rats were randomly assigned (10 animals/group) to: model, methotrexate (MTX)-treated (0.78 mg/kg body weight), and WJR-treated (22.9 g/kg) groups. Healthy normal rats (n=10) were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrifificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry.</p><p><b>RESULTS</b>Compared with the normal group, toe swelling degree was signifificantly increased in the model group (P<0.01). After treatment, toe swelling degree decreased signifificantly in the WJR and MTX groups compared with the model group (P<0.01). Compared with the normal group, expression of RANKL and LIGHT were signifificantly increased and OPG signifificantly decreased in peripheral blood and synovium of the model group (P<0.01). Conversely, RANKL and LIGHT expression were signifificantly reduced and OPG increased in the WJR and MTX groups compared with the model group (P<0.01). No statistically significant difference existed between WJR and MTX groups.</p><p><b>CONCLUSION</b>WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion.</p>