Role In Periprosthetic Osteolysis Research Articles

Calycosin alleviates titanium particle-induced osteolysis by modulating macrophage polarization and subsequent osteogenic differentiation.

Periprosthetic osteolysis (PPO) caused by wear particles is one of the leading causes of implant failure after arthroplasty. Macrophage polarization imbalance and subsequent osteogenic inhibition play a crucial role in PPO. Calycosin (CA) is a compound with anti-inflammatory and osteoprotective properties. This study aimed to evaluate the effects of CA on titanium (Ti) particle-induced osteolysis, Ti particle-induced macrophage polarization and subsequent osteogenic deficits, and explore the associated signalling pathways in a Ti particle-stimulated calvarial osteolysis mouse model using micro-CT, ELISA, qRT-PCR, immunofluorescence and western blot techniques. The results showed that CA alleviated inflammation, osteogenic inhibition and osteolysis in the Ti particle-induced calvarial osteolysis mouse model invivo. Invitro experiments showed that CA suppressed Ti-induced M1 macrophage polarization, promoted M2 macrophage polarization and ultimately enhanced osteogenic differentiation of MC3T3-E1 cells. In addition, CA alleviated osteogenic deficits by regulating macrophage polarization homeostasis via the NF-κB signalling pathway both invivo and invitro. All these findings suggest that CA may prove to be an effective therapeutic agent for wear particle-induced osteolysis.

PLGA nanoparticles engineering extracellular vesicles from human umbilical cord mesenchymal stem cells ameliorates polyethylene particles induced periprosthetic osteolysis

The wear particle-induced dissolution of bone around implants is a significant pathological factor in aseptic loosening, and controlling prosthetic aseptic loosening holds crucial social significance. While human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exos, Exos) have been found to effectively promote osteogenesis and angiogenesis, their role in periprosthetic osteolysis remains unexplored. To enhance their in vivo application, we engineered HucMSCs-Exos-encapsulated poly lactic-co-glycolic acid (PLGA) nanoparticles (PLGA-Exos). In our study, we demonstrate that PLGA-Exos stimulate osteogenic differentiation while inhibiting the generation of reactive oxygen species (ROS) and subsequent osteoclast differentiation in vitro. In vivo imaging revealed that PLGA-Exos released exosomes slowly and maintained a therapeutic concentration. Our in vivo experiments demonstrated that PLGA-Exos effectively suppressed osteolysis induced by polyethylene particles. These findings suggest that PLGA-Exos hold potential as a therapeutic approach for the prevention and treatment of periprosthetic osteolysis. Furthermore, they provide novel insights for the clinical management of osteolysis.

Particle-induced osteolysis is mediated by endoplasmic reticulum stress-associated osteoblast apoptosis

Osteoblast dysfunction plays a crucial role in periprosthetic osteolysis and aseptic loosening, and endoplasmic reticulum (ER) stress is recognized as an important causal factor of wear particle-induced osteolysis. However, the influence of ER stress on osteoblast activity during osteolysis and its underlying mechanisms remain elusive. This study aims to investigate whether ER stress is involved in the detrimental effects of wear particles on osteoblasts. Through our investigation, we observed elevated expression levels of ER stress and apoptosis markers in particle-stimulated bone specimens and osteoblasts. To probe further, we employed the ER stress inhibitor, 4-PBA, to treat particle-stimulated osteoblasts. The results revealed that 4-PBA effectively alleviated particle-induced osteoblast apoptosis and mitigated osteogenic reduction. Furthermore, our study revealed that wear particle-induced ER stress in osteoblasts coincided with mitochondrial damage, calcium overload, and oxidative stress, all of which were effectively alleviated by 4-PBA treatment. Encouragingly, 4-PBA administration also improved bone formation and attenuated osteolysis in a mouse calvarial model. In conclusion, our results demonstrate that ER stress plays a crucial role in mediating wear particle-induced osteoblast apoptosis and impaired osteogenic function. These findings underscore the critical involvement of ER stress in wear particle-induced osteolysis and highlight ER stress as a potential therapeutic target for ameliorating wear particle-induced osteogenic reduction and bone destruction.

The dual role of autophagy in periprosthetic osteolysis.

Periprosthetic osteolysis (PPO) induced by wear particles is an important cause of aseptic loosening after artificial joint replacement, among which the imbalance of osteogenesis and osteoclastic processes occupies a central position. The cells involved in PPO mainly include osteoclasts (macrophages), osteoblasts, osteocytes, and fibroblasts. RANKL/RANK/OGP axis is a typical way for osteolysis. Autophagy, a mode of regulatory cell death and maintenance of cellular homeostasis, has a dual role in PPO. Although autophagy is activated in various periprosthetic cells and regulates the release of inflammatory cytokines, osteoclast activation, and osteoblast differentiation, its beneficial or detrimental role remains controversy. In particular, differences in the temporal control and intensity of autophagy may have different effects. This article focuses on the role of autophagy in PPO, and expects the regulation of autophagy to become a powerful target for clinical treatment of PPO.

Identification of Thymidine Phosphorylase as a Potential Therapeutic Target for Bone Loss Associated Periprosthetic Osteolysis

Background: Macrophage-derived factors are generally thought to play a key role in the pathogenesis of aseptic loosening though initiating periprosthetic inflammation and pathological bone resorption. Therefore, the aim of this study was to identify macrophage-derived factors that promote osteoclast differentiation and periprosthetic bone destruction. Methods: We examined the effects of 12 macrophage-derived factors that were identified by RNA sequencing analysis of stimulated macrophages on osteoclast differentiation in vitro. The identified molecule was characterized as osteoclastogenic factor in vitro and in vivo. RNA-seq for the induced-osteoclasts was performed in an effort to understand its action mode. Therapeutic effects of Src kinase inhibitor were evaluated in implant particles-induced osteolysis murine model. Findings: Thymidine phosphorylase (TYMP) was found to induce the production of significant numbers of osteoclasts that exhibited resorbing activities on dentine slices. Functionally, TYMP silencing by siRNA reduced the number of osteoclasts in macrophages that had been stimulated with implant particles, suggesting a potential role in periprosthetic osteolysis. High levels of TYMP were detected in the serum and synovial tissues of patients that had been diagnosed with aseptic loosening. Moreover, the administration of TYMP onto calvariae of mice induced pathological bone resorption that was accompanied by an excessive infiltration of inflammatory cells and osteoclasts. Interestingly, TYMP stimulation appeared to activate the tyrosine kinase Fyn signaling associated with cell fusion and osteoclast formation. The oral administration of saracatinib, an FYN kinase inhibitor, significantly and consistently suppressed the formation of bone osteolytic lesions in implant wear particles-induced osteolysis model. Interpretation: Our findings highlight a novel molecular target for therapeutic intervention in implant loosening. Funding Information: Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research C;17K10993), Akiyama Life Science, Foundation and Kobayashi Foundation, and Japan Agencyfor Medical Research and Development (JP20gm6210004). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: The institutional review boards of Hokkaido University and hospital approved the study protocols for the use of human samples (approval ID: 016-0002). All participants signed an informed consent form for research use. Procedures for animal experiments were performed following protocols approved by the Institute of Animal Care and Use Committee of the Hokkaido University Graduate School of Medicine (no. 17-0085).

Comparison of Preoperative Bone Density in Patients With and Without Periprosthetic Osteolysis Following Total Ankle Arthroplasty.

Modern total ankle arthroplasty (TAA) prostheses are uncemented press-fit designs whose stability is dependent on bone ingrowth. Preoperative insufficient bone density reduces initial local stability at the bone-implant interface, and we hypothesized that this may play a role in periprosthetic osteolysis. We aimed to investigate the preoperative bone density of the distal tibia and talus and compare these in patients with and without osteolysis. We enrolled 209 patients (218 ankles) who underwent primary TAA using the HINTEGRA prosthesis. The overall mean follow-up duration was 66 (range, 24-161) months. The patients were allocated into 2 groups according to the presence of periprosthetic osteolysis: the osteolysis group (64 patients, 65 ankles) and nonosteolysis group (145 patients, 153 ankles). Between the 2 groups, we investigated and compared the radiographic outcomes, including the Hounsfield unit (HU) value around the ankle joint and the coronal plane alignment. HU values of the tibia and talus measured at 5 mm from the reference points were higher than those at 10 mm in each group. However, comparing the osteolysis and nonosteolysis groups, we found no significant intergroup difference in HU value at every measured level in the tibia and talus (P > .05). Concerning the coronal plane alignment, there were no significant between-group differences in the tibiotalar and talar tilt angles (P > .05). Patients with osteolysis showed similar preoperative bone density of the distal tibia and talus compared with patients without osteolysis. Our results suggest that low bone density around the ankle joint may not be associated with increased development of osteolysis. Level III, retrospective cohort study.

Melatonin suppresses Ti-particle-induced inflammatory osteolysis via activation of the Nrf2/Catalase signaling pathway

Aseptic loosening induced by osteolysis is recognized as a late complication of joint replacement. Osteoclasts stimulated by Titanium (Ti) nanoparticles play a critical role in periprosthetic osteolysis. Emerging evidence indicates that melatonin, a hormone primarily synthesized by the pineal gland, has been shown an inhibitory effect on osteoclast formation. However, it is unclear whether melatonin could suppress Ti-particle-induced osteoclastogenesis and what the underlying mechanisms were involved in. Herein, we aimed to investigate the effect of melatonin on osteoclast differentiation and osteolysis stimulated by Ti particles. Our results showed that the in vitro osteoclastogenesis of mouse bone marrow monocytes (BMMs) stimulated by Ti particles was suppressed by melatonin treatments in a dose-dependent manner. Further experiments revealed that melatonin up-regulated the expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) and catalase (CAT) at both the mRNA and protein levels. The role of the Nrf2/CAT signaling pathway was confirmed by the fact that silencing the expression of NRF2 by small interfering RNA (siRNA) counteracted the anti-osteolysis effects of melatonin. Furthermore, in vivo intraperitoneal injection of melatonin successfully attenuated periprosthetic osteolysis induced by Ti particles in a murine calvarial model. Our findings demonstrate that melatonin is a promising therapeutic agent for treating periprosthetic osteolysis by inhibiting the Ti-particle-stimulated osteoclastogenesis via activation of the Nrf2/Catalase signaling pathway.

In vivo analysis of the effects of CoCrMo and Ti particles on inflammatory responses and osteolysis.

Metal wear particles play a major role in periprosthetic osteolysis and aseptic loosening in patients with total joint arthroplasty. The ability to induce osteolysis depends on the size, shape, dose, and type of the particles. However, much remains unknown regarding which type of metal particles are most reactive. We compared the inflammatory response and bone loss induced by two metal wear particles, cobalt–chromium–molybdenum (CoCrMo) and titanium (Ti), in a mouse calvaria model of osteolysis. We found that CoCrMo particles caused markedly greater bone resorption than Ti particles, according to three-dimensional images of the calvariae. CoCrMo particles activated more functional osteoclasts by significantly increasing the expression of the osteoclast-specific gene tartrate-specific acid phosphatase (Trap), calcitonin receptor (Ctr), and nuclear factor of activated T cells c1 (Nfatc1), and induced a greater increase in the ratio of receptor activator of nuclear factor kappa B ligand (RANKL)/osteoprotegerin (OPG) than Ti particles. CoCrMo particles also induced a stronger local inflammatory response, markedly increasing the expression and secretion of tumor necrosis factor-α and interleukin-1β compared with Ti particles. Therefore, CoCrMo particles induced a more severe inflammatory response and greater osteolysis than Ti particles in vivo.

Calcineurin/NFAT signaling pathway mediates titanium particle‑induced inflammation and osteoclast formation by inhibiting RANKL and M‑CSF invitro.

Wear particles serve a central role in periprosthetic osteolysis, which leads to the aseptic loosening of prostheses. In the present study a lentiviral vector was constructed to silence macrophage colony stimulating factor (M‑CSF) and receptor activator of nuclear factor κ‑B ligand (RANKL) genes, which synergistically inhibit osteoclast formation and differentiation. To confirm the role of the calcineurin/nuclear factor of activated T cells (NFAT) pathway in osteolysis, we transduced murine macrophage/monocyte RAW264.7 cells with M‑CSF‑short hairpin (sh)RNA‑RANKL‑shRNA. Tumor necrosis factor‑α (TNF‑α) protein levels were evaluated using enzyme‑linked immunosorbent assay. Transduced RAW264.7 cells were cultured in Transwell chambers in the presence of 0.1mg/ml titanium particles to investigate the capacity of TNF‑α inhibition to reduce wear debris‑induced inflammation. RANKL, M‑CSF, TNF‑α, interleukin (IL)‑1β, IL‑6 and NFATc1 mRNA levels were also assessed by reverse transcription‑quantitative polymerase chain reaction. Osteoclastogenesis was measured by tartrate‑resistant acid phosphatase (TRAP) mRNA quantification. Lentiviral‑mediated double gene inhibition is known to be able to completely inhibit inflammatory osteolysis, simultaneously decreasing the number of NFATc1‑ and TRAP‑positive cells. The present study confirmed that the combined silencing of M‑CSF and RANKL genes can inhibit the osteolysis induced by the wear particles around the prosthesis. The calcineurin/NFAT pathway serves a role in the prevention of prosthesis loosening.

The induction of CXCR4 expression in human osteoblast-like cells (MG63) by CoCr particles is regulated by the PLC-DAG-PKC pathway.

Osteolysis which leads to aseptic loosening of implants is a fundamental problem in joint replacement surgery (arthroplasty) and the leading cause for implant failure and revision surgery. Metal (CoCr) particles separated from implants by wear cause osteolysis and the failure of orthopedic implants, but the molecular mechanism is not clear. The chemokine receptor CXCR4 has been shown to play a pivotal role in periprosthetic osteolysis. The aim of this study was to determine which signal transduction pathway (PLC-DAG-PKC or MAPK/ERK) induces CXCR4 expression in osteoblast-like cells (MG63) cells. MG63 and Jurkat cells were stimulated with different amounts of particles (107 , 106 , and 105 ) for different time periods (30 min to 24 h), in the presence and absence of specific inhibitors (chelerythrine for the PLC-DAG-PKC pathway and PD98059 for the MAPK/ERK pathway). The expression of CXCR4-specific mRNA was determined by real-time polymerase chain reaction (PCR), and the PKC activity was measured by Western Blot using an antibody specific for PKC-related phosphorylation. Real-time PCR data showed that CXCR4 mRNA expression in MG63 cells induced by CoCr particles was significantly diminished by the PKC-specific inhibitor chelerythrine. This effect was not observed with the MAPK/ERK inhibitor PD98059. The involvement of PKC was also confirmed by an intensified phosphorylation pattern after stimulation with CoCr particles. In Jurkat cells, none of the inhibitors exhibited any effect. The induction of CXCR4-specific mRNA expression in MG63 cells after stimulation with CoCr particles is regulated by the PLC-DAG-PKC pathway and not by the MAPK/ERK pathway. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2326-2332, 2017.

Changes in protein expression associated with chronic in vitro exposure of hexavalent chromium to osteoblasts and monocytes: A proteomic approach

Cr (VI) is a well-recognized environmental toxin and carcinogen. It is known to be released from orthopedic metal implants in-situ by biocorrosion and is speculated to play a role in periprosthetic osteolysis. It is hence essential to understand its long-term biological effects. We have assessed the in vitro responses of osteoblasts and monocytes to chronic exposure (3 weeks) to Cr (VI), at concentrations that have been measured in patients with metal implants, using two-dimensional gel electrophoresis. Cr (VI) exposure resulted in a differential time-dependent regulation of glycolytic, stress, and cytoskeletal proteins. The proteins that have been found to be altered in expression play an essential role in normal cellular functioning such as energy metabolism, cell signaling, and proliferation. The results highlight the complex molecular changes that occur in both cell types with long-term exposure to Cr and may be useful in establishing a series of clinically useful biomarkers to monitor long-term use of metallic implants.

Cobalt ions induce chemokine secretion in primary human osteoblasts

Chemokines are major regulators of the inflammatory response and have been shown to play an important role in periprosthetic osteolysis. Titanium particles have previously been shown to induce IL-8 and MCP-1 secretion in osteoblasts. These chemokines result in the chemotaxis and activation of neutrophils and macrophages, respectively. Despite a resurgence in the use of cobalt-chromium-molybdenum alloys in metal-on-metal arthroplasty, cobalt and chromium ion toxicity in the periprosthetic area has been insufficiently studied. In this study we investigate the in vitro effect of cobalt ions on primary human osteoblast activity. We demonstrate that cobalt ions rapidly induce the protein secretion of IL-8 and MCP-1 in primary human osteoblasts. This elevated chemokine secretion is preceded by an increase in the transcription of the corresponding chemokine gene. Using a Transwell migration chemotaxis assay we also demonstrate that the chemokines secreted are capable of inducing neutrophil and macrophage migration. Furthermore, cobalt ions significantly inhibit osteoblast function as demonstrated by reduced alkaline phosphatase activity and calcium deposition. In aggregate these data demonstrate that cobalt ions can activate transcription of the chemokine genes IL-8 and MCP-1 in primary human osteoblasts. Cobalt ions are not benign and may play an important role in the pathogenesis of osteolysis by suppressing osteoblast function and stimulating the production and secretion of chemokines that attract inflammatory and osteoclastic cells to the periprosthetic area.

Synergistic effect of particles and cyclic pressure on cytokine production in human monocyte/macrophages: proposed role in periprosthetic osteolysis

Macrophages, activated by particulate wear debris, are important in the process of osteolysis, which occurs during joint implant loosening. We previously found increased levels of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in cultured macrophages subjected to cyclical pressure of 0.138 MPa, suggesting that cyclic pressure may be another relevant cause of macrophage activation. The current study first investigated the effects of a range of cyclic pressures on cultured macrophages, including an investigation of the time course of cytokine expression. At 0.138 MPa, supernatant levels of TNF-α were maximal at 12 h, whereas IL-6 and IL-1β were maximal at 24 h. All four cyclic pressure levels tested (without particles) resulted in increased production of all three cytokines relative to control. These increases were most marked at 0.069 and 0.035 MPa, and the increase in cytokine production at 0.017 MPa was not statistically significant. Further studies demonstrated that conditioned media from cyclically pressurized macrophages stimulated bone resorption in a neonatal mouse calvarial assay system. There were increased levels of calcium released from calvaria cultured in conditioned media from pressurised monocytes, and an increase in tartate-resistant acid phosphatase–positive osteoclasts was observed microscopically. As particulate wear debris is important in implant loosening, ultra high molecular weight polyethylene particles were also added to the pressurized cell cultures. The experiments compared the effect of atmospheric pressure, cyclic pressure alone, particles alone, and particles and cyclic pressure combined. A combination of ultra high molecular weight polyethylene particles and cyclic pressure at 0.017 MPa resulted in a dramatic synergistic elevation of levels of all three cytokines compared with the levels found with either pressure or particles alone. We propose that monocyte/macrophage activation by cyclic pressure plays a major role in the osteolysis seen in aseptic loosening of implants. The synergistic effect observed between particles and pressure could accelerate implant loosening, and implies that reduction in either cyclic pressure (by improving implant fixation) or wear debris load would reduce osteolysis.

Effect of particle size on macrophage-osteoclast differentiation in vitro

To determine whether particle size affects macrophage-osteoclast differentiation in vitro, latex beads of 0.1, 1, and 10μm in diameter were added to a murine macrophage-UMR106 osteoblast-like cell coculture system. The extent of osteoclast differentiation was determined by assessing the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells on glass coverslips and the extent of lacunar resorption on dentine slices. The addition of particles, 1 and 10μm in size, to the cocultures resulted in a significant increase in the number of TRAP-positive osteoclast-like cells and in the resorption pit surface area compared with findings in control cultures to which no particles had been added. Particles 0.1μm in size also stimulated osteoclast formation relative to the control; however, the difference was not significant. These results indicate that particles, particularly these 1 and 10μm in size, sizes which were phagocytosable, significantly enhanced the process of macrophage-osteoclast differentiation and suggest that particle size plays an important role in periprosthetic osteolysis.

Progressive bilateral pelvic osteolysis in a patient with McKee—Farrar metal—metal total hip prostheses

As accumulating evidence indicates that polyethylene plays a central role in periprosthetic osteolysis, there is a renewed interest in alternatives such as metal—metal bearings. Several long-term studies report encouraging results with the McKee—Farrar total hip arthroplasty, but there is a paucity of data on the incidence, severity, and pathogenesis of osteolysis in metal—metal bearing total hip arthroplasties. This study presents a patient who had progressive bilateral pelvic osteolysis associated with his McKee—Farrar metal—metal total hip prostheses. His left hip was revised after 13.5 years of service. The tissues revealed no gross metal staining and fewer inflammatory constituents than are typically found in metal—polyethylene bearing hips. His right hip was still functioning after 22.5 years of service, although the acetabular component was loose by that point. An arthrogram of this hip demonstrated communication of the joint with the iliac osteolysis. The development of osteolysis in both hips followed a pattern similar to that seen in metal—polyethylene total hip arthroplasties. Bearing wear could not be detected in either of the hips. Accumulating evidence indicates that particulate debris of appropriate size and number is capable of fueling periprosthetic inflammation. Specific to this study, consideration should be given to particles of cobalt—chromium alloy, polymethyl methacrylate bone—cement, and barium sulfate. Other factors that should be considered are increased joint fluid pressure, soluble inflammatory mediators, and the effective joint space. When bone becomes part of the effective joint space, it is exposed to particulate debris, soluble factors, and potentially increased joint fluid pressures, which may promote localized bone resorption. It must be kept in mind that the development of osteolysis is multifactorial. Although bearings with better wear characteristics are desirable, the elimination of polyethylene will not eliminate osteolysis.

The potential role of fibroblasts in periprosthetic osteolysis: fibroblast response to titanium particles.

Periprosthetic osteolysis with or without aseptic loosening is a major clinical problem in total hip arthroplasty. While the macrophage response to prosthetic wear debris and its role in periprosthetic osteolysis has been extensively studied, information regarding other cell types (fibroblasts, osteoblasts) is limited. This study explored the response of fibroblasts to particulate wear debris. Fibroblasts isolated from interfacial membranes of patients with failed total hip replacements and normal synovial tissue, when challenged with small-sized ( < 3 microns) titanium (Ti) particles, responded with significantly enhanced expressions of collagenase, stromelysin and, to a much lesser extent, their tissue inhibitor of metalloproteinases (TIMP). These "regulated" expressions at both mRNA and protein levels were correlated with the size and composition of particles. De novo protein synthesis was required for the regulation of these mRNAs. A similar effect could be induced by the treatment of the cells with particle-free conditioned medium from Ti particle-stimulated fibroblasts. Furthermore, this conditioned medium significantly suppressed the mRNA levels of procollagen alpha 1 (I) and alpha 1 (III) in osteoblast-like MG-63 cells. It is concluded that fibroblasts stimulated with certain particle debris may play an important role in periprosthetic osteolysis by releasing bone-resorbing metalloproteinases and mediator(s) which resulted in suppressed collagen synthesis in osteoblasts.

Wear particles of total joint replacements and their role in periprosthetic osteolysis.

Total joint arthroplasties with metal, plastic, and acrylic materials have revolutionized the surgical treatment of arthritis. Wear of the materials at the articulation and at the sites of attachment to skeleton, however, is a major long-term concern. The particles liberated by fatigue, abrasion, fretting, and corrosion cause foreign body granulomatous reaction in the periprosthetic tissue. This can lead to the activation of cells to produce a variety of cytokines and proteolytic enzymes that can, by complex mechanisms, cause periprosthetic osteolysis and loosening. The mechanisms involved in the production of the wear particles and their biologic consequences are discussed in this report.