osteoprotegerin and Osteonecrosis

Aseptic bone loss adjacent to orthopedic joint implants is a common cause of joint implant failure in humans. This study investigates the expression of key regulators of osteoclast formation, receptor activator NFkappaB (RANK), Receptor activator of NFkappaB ligand (RANKL) and osteoprotegerin (OPG), in the peri-implant tissues of patients with osteolysis compared with levels in synovial tissues from osteoarthritic and healthy subjects. Immunohistochemical studies demonstrated that significantly higher levels of RANKL protein (p<0.05) were found in the peri-implant tissues of patients with implant failure than in similar tissues from osteoarthritic and healthy subjects. In contrast, OPG protein levels were similar in all tissues. RANKL, expressed as mRNA and protein, was predominantly associated with cells containing wear particles. Dual labeling studies showed that the cells expressing RANKL protein were macrophages. In situ hybridization studies confirmed that mRNA encoding for these proteins is also expressed by cells in the peri-implant tissues. In addition, RANK mRNA was expressed in cells that contained wear particles. These findings show that abnormally high levels of RANKL are expressed in peri-implant tissues of patients with prosthetic loosening and that these abnormal levels of RANKL may significantly contribute to aseptic implant loosening.

Topics: Adult; Aged; Aged, 80 and over; Carrier Proteins; Female; Foreign-Body Reaction; Glycoproteins; Humans; Male; Membrane Glycoproteins; Middle Aged; NF-kappa B; Osteoarthritis; Osteoclasts; Osteolysis; Osteonecrosis; Osteoprotegerin; Prosthesis Failure; Prosthesis-Related Infections; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Receptors, Cytoplasmic and Nuclear; Receptors, Tumor Necrosis Factor

Topics: Animals; Cell Proliferation; Core Binding Factor Alpha 1 Subunit; Disease Models, Animal; Femur Head; Flavonoids; Gene Expression Regulation; Humans; Male; Osteoblasts; Osteogenesis, Distraction; Osteonecrosis; Osteoprotegerin; Phosphatidylinositol 3-Kinases; Plant Extracts; Polypodiaceae; Proto-Oncogene Proteins c-akt; RANK Ligand; Rats; Reactive Oxygen Species; Signal Transduction; Steroids

Aseptic loosening caused by wear particles is a common complication after total hip arthroplasty. We investigated the effect of the quercetin on wear particle-mediated macrophage polarization, inflammatory response and osteolysis. In vitro, we verified that Ti particles promoted the differentiation of RAW264.7 cells into M1 macrophages through p-38α/β signalling pathway by using flow cytometry, immunofluorescence assay and small interfering p-38α/β RNA. We used enzyme-linked immunosorbent assays to confirm that the protein expression of M1 macrophages increased in the presence of Ti particles and that these pro-inflammatory factors further regulated the imbalance of OPG/RANKL and promoted the differentiation of osteoclasts. However, this could be suppressed, and the protein expression of M2 macrophages was increased by the presence of the quercetin. In vivo, we revealed similar results in the mouse skull by μ-CT, H&E staining, immunohistochemistry and immunofluorescence assay. We obtained samples from patients with osteolytic tissue. Immunofluorescence analysis indicated that most of the macrophages surrounding the wear particles were M1 macrophages and that pro-inflammatory factors were released. Titanium particle-mediated M1 macrophage polarization, which caused the release of pro-inflammatory factors through the p-38α/β signalling pathway, regulated OPG/RANKL balance. Macrophage polarization is expected to become a new clinical drug therapeutic target.

Topics: Animals; Arthroplasty, Replacement, Hip; Cell Differentiation; Cell Polarity; Gene Expression Regulation, Developmental; Humans; Macrophages; Mice; Osteoclasts; Osteonecrosis; Osteoprotegerin; p38 Mitogen-Activated Protein Kinases; Quercetin; RANK Ligand; RAW 264.7 Cells; Skull; Titanium

Bone diseases represent an increasing health burden worldwide, and basic research remains necessary to better understand the complexity of these pathologies and to improve and expand existing prevention and treatment approaches. In the present study, 216 bone samples from the caput femoris and collum femoris of 108 patients with degenerative or dysplastic coxarthrosis, hip fracture, or osteonecrosis were evaluated for the proportion of trabecular bone (TB) and expression of parathyroid hormone (PTH) type 1 receptor (PTH1R), osteoprotegerin (OPG), and receptor activator of nuclear factor kappa-B ligand (RANKL). Serum levels of PTH, OPG, soluble RANKL (sRANKL), alkaline phosphatase (AP), osteocalcin, total procollagen type-1 intact N-terminal propeptide (TP1NP), tartrate-resistant acid phosphatase type 5b (TRAP5b), sclerostin, and C-telopeptide of type-1 collagen (ICTP) were also determined. Age was positively correlated with serum levels of PTH, OPG, and sclerostin but negatively associated with TB and sRANKL. Women exhibited less TB, lower sclerostin and ICTP, and higher TRAP5b. Impaired kidney function was associated with shorter bone decalcification time, less TB, lower sRANKL, and higher serum PTH, OPG, and sclerostin. Furthermore, correlations were observed between bone PTH1R and OPG expression and between serum PTH, OPG, and AP. There were also positive correlations between serum OPG and TP1NP; serum OPG and sclerostin; serum AP, osteocalcin, and TRAP5b; and serum sclerostin and ICTP. Serum OPG was negatively associated with sRANKL. In summary, clear relationships between specific bone metabolism markers were observed, and distinct influences of age, sex, and kidney function, thus underscoring their suitability as diagnostic or prognostic markers.

Topics: Adult; Aged; Aged, 80 and over; Cancellous Bone; Female; Hip Fractures; Humans; Male; Middle Aged; Osteoarthritis, Hip; Osteocalcin; Osteonecrosis; Osteoprotegerin; Parathyroid Hormone; RANK Ligand

Through a process called perilacunar remodeling, bone-embedded osteocytes dynamically resorb and replace the surrounding perilacunar bone matrix to maintain mineral homeostasis. The vital canalicular networks required for osteocyte nourishment and communication, as well as the exquisitely organized bone extracellular matrix, also depend upon perilacunar remodeling. Nonetheless, many questions remain about the regulation of perilacunar remodeling and its role in skeletal disease. Here, we find that suppression of osteocyte-driven perilacunar remodeling, a fundamental cellular mechanism, plays a critical role in the glucocorticoid-induced osteonecrosis. In glucocorticoid-treated mice, we find that glucocorticoids coordinately suppress expression of several proteases required for perilacunar remodeling while causing degeneration of the osteocyte lacunocanalicular network, collagen disorganization, and matrix hypermineralization; all of which are apparent in human osteonecrotic lesions. Thus, osteocyte-mediated perilacunar remodeling maintains bone homeostasis, is dysregulated in skeletal disease, and may represent an attractive therapeutic target for the treatment of osteonecrosis.

Topics: Animals; Bone Matrix; Bone Remodeling; Cathepsin K; Delayed-Action Preparations; Gene Expression Regulation; Glucocorticoids; Humans; Male; Matrix Metalloproteinase 13; Matrix Metalloproteinase 14; Matrix Metalloproteinase 2; Mice; Osteocytes; Osteonecrosis; Osteoprotegerin; Prednisolone; RANK Ligand; Tartrate-Resistant Acid Phosphatase; Transcription Factors

The RANKL/RANK/OPG pathway plays an important role in regulating bone remodeling and bone turnover. However, the association of the genes variants with the risk of ONFH has rarely been reported. Here, we analyzed the correlation of the 10 SNPs polymorphisms of RANKL, RANK, OPG, TRAF6, and NFATC1 genes with the risk and development of ONFH in 200 ONFH patients and 177 health controls of Chinese population with using Mass ARRAY® platform. The results showed that the recessive model of NFATC1rs9518 was significantly associated with increased ONFH risk (OR:8.223,

Topics: Aged; China; Female; Femur Head Necrosis; Genetic Association Studies; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Male; Middle Aged; NFATC Transcription Factors; Osteonecrosis; Osteoprotegerin; Polymorphism, Single Nucleotide; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Signal Transduction; Tumor Necrosis Factor Receptor-Associated Peptides and Proteins

Steroid, also known as glucocorticoid, induced osteonecrosis of the femoral head in young adults, which has been a challenging disorder for the frequent incidence of collapse of femoral head, leading to dysfunction of hip joint and impairing life quality of human. Bioavailable and less toxic synthetic retinoids, such as the atypical adamantyl retinoid ST1926, have been developed and investigated in clinical trials for many diseases. Serum lipid-related indicators were assessed to elucidate the role of ST1926 in regulating lipid metabolism. Microfocal computed tomography (Micro-CT) was included to explore the effects of ST1926 treatment on microstructure and bone mass. Then, the role of ST1926 treatment in regulating osteoclast differentiation was also evaluated in vivo and in vitro. In addition, alkaline phosphatase (ALP), osteoprotegerin (OPG), bone alkaline phosphatase (BAP) and bone morphogenic protein (BMP) expression in serum and cells were detected at protein or mRNA levels. The ratio of empty lacuna in the bone tissue samples was significantly low in ST1926-treated groups than in the control group. Micro-CT evaluation suggested that ST1926 treatment could ameliorate the microstructure of the bone and up-regulate bone mineral density in steroid-induced rats. Moreover, ST1926 treatment suppressed osteoclast differentiation and promoted bone formation markers. Also, OPG, ALP, and Wnt3a/β-catenin down-regulation as well as inflammation up-regulation could be reversed by ST1926 administration through NFκB inhibition. Hence, ST1926 may inhibit steroid-induced osteoporosis and promote steroid-induced bone remodeling by regulating the Wnt3a/β-catenin/NFκB signaling pathway. J. Cell. Biochem. 118: 2072-2086, 2017. © 2017 Wiley Periodicals, Inc.

Topics: Adamantane; Alkaline Phosphatase; Animals; beta Catenin; Bone Density; Bone Density Conservation Agents; Bone Morphogenetic Proteins; Bone Resorption; Cinnamates; Gene Expression Regulation; Male; Methylprednisolone; Methylprednisolone Acetate; NF-kappa B; Osteoblasts; Osteoclasts; Osteonecrosis; Osteoprotegerin; Rats; Rats, Wistar; Signal Transduction; Wnt3A Protein

To evaluate the effects of green tea intake and zoledronic acid intravenous therapy on teeth socket repair.. Sixty male albinus Wistar rats were divided into 4 groups: C-Control, intravenous (IV) 0.9% saline solution (SS), GT-1% green tea in drinking water and IV SS, BP-IV zoledronic acid (BP), and BP+GT-IV BP and 1% green tea. 0.035mg/kg of BP was administered every two weeks. After ten weeks, right upper molars were extracted and the green tea started to be offered for GT and BP+GT. After 7, 14, and 28days the animals were euthanized.. Histopathology analysis revealed lack of socket repair in BP and BP+GT groups, which presented significant increased number of polimorphonuclear leukocytes at day 28, in comparison with C (p<0.05). No significant differences were detected between C and the experimental groups at the same period (p<0.05) when considering mononuclear leukocytes. Immunolabeling revealed that the association of BP and GT caused a slight disturbance in OPG/RANKL system and retarded Runx-2 labeling. Although strong TRAP labeling was observed, most of the positive cells in BP and BP+GT groups were not located on bone surface.. Socket healing of rats treated with BP and regular drinking green tea presented no relevant differences in comparison to those treated with BP alone.

Topics: Animals; Core Binding Factor Alpha 1 Subunit; Diphosphonates; Drug Combinations; Imidazoles; Immunohistochemistry; Leukocytes; Male; Maxilla; Osteonecrosis; Osteoprotegerin; Plant Extracts; Rats; Rats, Wistar; Tartrate-Resistant Acid Phosphatase; Tea; Tooth Socket; Wound Healing; Zoledronic Acid

Osteonecrosis, also termed aseptic necrosis, is the cellular death of bone components due to interruption of the blood supply. Glucocorticoid (GC) therapy is a common non-traumatic cause of osteonecrosis. However, the mechanism by which GCs induce osteonecrosis remains to be elucidated. The aim of the present study was to investigate the effects of GCs on osteoclast and osteoblast differentiation and function in a GC‑induced osteonecrosis mouse model. BALB/c male mice (n=40; 4‑weeks‑old) were treated with dexamethasone and asparaginase for 8 weeks. The control group (n=20) was administered normal saline. The results demonstrated that the GC-treated group had a lower mean weight compared with the control group. Morphologically, 16/37 (43%) mice demonstrated significant osteonecrotic lesions in the GC‑treated group. However, osteonecrotic lesions were not observed in the mice of the control group. Furthermore, immunohistochemistry demonstrated that the GC‑treated group had a higher level of osteoprotegerin compared with the control group, without any change in the expression of receptor activator of nuclear factor‑κB ligand. In addition, tartarate‑resistant acid-phosphatase staining demonstrated significantly decreased osteoclasts in the areas of bone destruction in the GCs-treated group. Furthermore, the present study demonstrated that GCs increased expression levels of osterix and osteocalcin, and decreased expression of matrix metallopeptidase‑9 to regulate the differentiation and function of osteoblasts and osteoclasts. The results of the present study suggested that GCs influence bone remolding resulting in decreased osteoclasts formation/differentiation. Therefore, regulating the differentiation and activity of the osteoclasts may be beneficial to the control and treatment of osteonecrosis.

Topics: Animals; Biomarkers; Body Weight; Cell Differentiation; Dexamethasone; Disease Models, Animal; Gene Expression; Glucocorticoids; Male; Matrix Metalloproteinase 9; Mice; Osteoblasts; Osteocalcin; Osteoclasts; Osteogenesis; Osteonecrosis; Osteoprotegerin; RANK Ligand; RNA, Messenger; Tartrate-Resistant Acid Phosphatase

Steroid-induced osteonecrosis of the femoral head (steroid-induced ONFH) presents great challenges due to the various effects of steroids on multi-system pathways involved into osteoblast differentiation, osteoblast and osteoclast apoptosis, lipid metabolism, calcium metabolism and coagulation. As one of the most frequently used herbs in Traditional Chinese Medicine formulas that are prescribed for the regulation of bone and mineral metabolism, the therapeutic effects of Achyranthes bidentata on steroid-induced ONFH remain unclear. Thus, the aim of the current study was to verify whether Achyranthes bidentata extract (ABE) can be used to prevent steroid-induced ONFH and to investigate its underlying pharmacological mechanisms.. Steroid-induced ONFH rat models were established to evaluate the effects of ABE treatment on osteonecrotic changes and repair processes. Microfocal computed tomography (Micro-CT) was performed to assess the effects of ABE treatment on bone mass, microstructure, and vascularization. Then, the effects of ABE treatment on osteoclast differentiation and bone formation were also evaluated in vivo and in vitro. In addition, receptor activator of nuclear factor kappa B (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) expression in sera, femoral heads and bone marrow-derived mesenchymal stem cells (BMSCs) were detected at both protein and mRNA levels.. The ratio of empty lacuna, adipose tissue area, and adipocyte perimeter in the bone marrow were markedly lower in the ABE treatment groups than in the model group. Micro-CT evaluation indicated that ABE treatment could improve the microstructure of the trabecular bone, increase bone mineral density and promote vascularization in steroid-induced ONFH rats. Moreover, ABE treatment inhibited osteoclast differentiation and activated bone formation markers. Interestingly, OPG downregulation, RANK and RANKL upregulation, and an increased ratio of RANKL to OPG in sera and necrotic femoral head could be reversed by ABE treatment, which also effectively inhibited RANKL-induced osteoclast differentiation and regulated RANKL and OPG expression of in vitro.. ABE may prevent steroid-induced ONFH and alleviate steroid-induced bone deterioration by regulating the RANKL/RANK/OPG signaling pathway.

Topics: Achyranthes; Animals; Base Sequence; Bone Density; Bone Development; Cell Differentiation; DNA Primers; Femur Head; Male; Mice; Mice, Inbred C57BL; Osteoclasts; Osteonecrosis; Osteoprotegerin; Plant Extracts; Prednisolone; RANK Ligand; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; Receptor Activator of Nuclear Factor-kappa B; Signal Transduction

The aim of this study was to compare clodronate and zoledronic acid regarding their influence on the repair of surgical wounds in maxillae (soft tissue wound and tooth extraction) and their relation to osteonecrosis.. Thirty-four Wistar rats were allocated into three groups according to the treatment received: (i) 12 animals treated with zoledronic acid, (ii) 12 animals treated with clodronate and (iii) 10 animals that were given saline solution. All animals were subjected to tooth extractions and surgically induced soft tissue injury. Histological analysis of the wound sites was performed by means of hematoxylin-eosin (H&E) staining and immunohistochemical staining for receptor activator of nuclear factor-kB ligand (RANKL), osteoprotegerin (OPG), von Willebrand factor, and caspase-3.. The zoledronic acid group showed higher incidence of non-vital bone than did the clodronate group at the tooth extraction site. At the soft tissue wound site, there were no significant differences in non-vital bone between the test groups. RANKL, OPG, von Willebrand factor, and caspase-3 did not show significant differences between the groups for both sites of surgical procedures.. Both of the bisphosphonates zoledronic acid and clodronate are capable of inducing maxillary osteonecrosis. Immunohistochemical analysis suggests that the involvement of soft tissues as the initiator of osteonecrosis development is less probable than has been pointed out.

Topics: Animals; Bacterial Load; Bone Density Conservation Agents; Caspase 3; Clodronic Acid; Connective Tissue; Diphosphonates; Epithelium; Female; Imidazoles; Maxilla; Maxillary Diseases; Mouth Mucosa; Osteonecrosis; Osteoprotegerin; RANK Ligand; Rats; Rats, Wistar; Tooth Extraction; Tooth Socket; von Willebrand Factor; Wound Healing; Zoledronic Acid

Bisphosphonate induced osteonecrosis of the jaw (BONJ) is a complication in patients taking bisphosphonate (BP) that affects their quality of life and compliance. In this cohort study, patients with multiple myeloma (MM) on intravenous BP therapy were enrolled over 1 year. Demographic and clinical data and genotyping of 10 single nucleotide polymorphisms (SNPs) from seven candidate genes associated with drug or bone metabolism were determined. Of the 78 patients enrolled, 12 had BONJ. The median time to developing BONJ was 28 months. Univariate and multivariate analysis revealed a significant association between BONJ and smoking (p=0.048) and type of BP treatment (p=0.03). A trend for higher odds for BONJ was found for SNPs in five genes: COL1A1 (rs1800012), RANK (rs12458117), MMP2 (rs243865), OPG (rs2073618) and OPN (rs11730582). Considering all five SNPs together, patients with genotype scores ≥ 5 had a BONJ event rate of 57%; those with scores < 5 had a rate of 10%. The adjusted odds ratio was 11.2 (95% confidence interval of 1.8-69.9; p value 0.0097). Smoking, type of BP and combined genotype score of COL1A1, RANK, MMP2, OPG and OPN were significantly associated with BONJ in MM patients undergoing BP therapy.

Topics: Adult; Aged; Aryl Hydrocarbon Hydroxylases; Bone Density Conservation Agents; Cohort Studies; Collagen Type I; Collagen Type I, alpha 1 Chain; Cytochrome P-450 CYP2C8; Diphosphonates; Female; Gene Frequency; Humans; Imidazoles; Injections, Intravenous; Jaw Diseases; Male; Matrix Metalloproteinase 2; Middle Aged; Multiple Myeloma; Osteonecrosis; Osteopontin; Osteoprotegerin; Pamidronate; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Receptor Activator of Nuclear Factor-kappa B; Risk Factors; Smoking; Time Factors; Tumor Necrosis Factor-alpha; Zoledronic Acid