Aseptic Loosening Of Artificial Joints Research Articles

‘STING’ PROMOTES TITANIUM PARTICLE-INDUCED MACROPHAGE INFLAMMATION

Aseptic inflammation is the main factor causing aseptic loosening of artificial joints. Studies have shown that inflammatory cells can activate STING (stimulator of interferon genes, STING) after being stressed. This study aims to explore the specific mechanism of STING in aseptic loosening of artificial joints, and provide new strategies for disease prevention.Titanium particles with a diameter of 1.2-10 μm were prepared to stimulate macrophages (RAW 264.7) to simulate the periprosthetic microenvironment. A lentiviral vector targeting the STING gene was designed and transfected into macrophages to construct a cell line targeting STING knockdown. The expression and secretion levels of TNF-α were detected by qPCR and ELISA, the activation levels of inflammatory pathways (NF-κB, IRF3, etc.) were detected by western blot, and the nucleus translocation of P65 and IRF3 was observed by cellular immunofluorescence.After titanium particles stimulated macrophages, qPCR and ELISA showed that the transcription and secretion levels of TNF-α were significantly increased. Western blot showed that titanium particle stimulation could increase the phosphorylation levels of NF-κB and IRF3 pathways. While knockdown of STING can significantly reduce titanium particle-induced TNF production, attenuate the activation levels of NF-κB and IRF3 pathways as well as the nucleus translocation of P65 and IRF3.Conclusions: STING positively regulates the level of inflammation in macrophages induced by titanium particles, and targeted inhibition of STING can reduce inflammation, which may delay the progression of aseptic loosening of artificial joints.

Mechanism of Xianlinggubao Capsule Regulating RANKL / RANK / OPG Signaling Pathway and Inhibiting Aseptic Loosening of Artificial Joint

Mechanism of Xianlinggubao Capsule Regulating RANKL / RANK / OPG Signaling Pathway and Inhibiting Aseptic Loosening of Artificial Joint

Research on the inhibition for aseptic loosening of artificial joints by Sr-doped calcium polyphosphate (SCPP) in vivo

Aseptic loosening of artificial joints is the most common complication after artificial joint replacement. Finding the solution to tackle aseptic loosening of artificial joints is a focus in bone and joint surgery research field. In vitro studies of Sr-doped calcium polyphosphate (SCPP) have found by our team that it could promote osteoblast proliferation and inhibit osteoclast activity, and it has a potential inhibitory effect on aseptic loosening by suppressing the expression of receptor activator of nuclear factor-κ B ligand and improving the expression of OPG. The present study aims to confirm the conclusion in vitro by the mean of animal experiment. The Ti rod prosthesis coated with SCPP, calcium polyphosphate (CPP), and Ultra-high molecular weight polyethylene (UHMWPE were implanted in the femur (the internal surface of bone tunnel was also coated with SCPP, CPP and UHMWPE respectively). Radiography (x-rays, micro-CT), histochemistry (Hematoxylin-eosin staining (HE), methylene blue-acid fuchsin, Von Kossa histological staining), molecular biology (alkaline phosphatase and TRAP5b factors, Mir21-5p and Mir 26a-5p) were performed to analyzed the effects of SCPP within 20 weeks. The Radiography results showed that osteolysis with various severity occurred in all groups, and SCPP group had the mildest osteolysis. Histochemistry results showed that arthritis was milder in SCPP and CPP groups, while the bone formation in SCPP group was most significant. Its bone reconstruction effect was the best as well. The Molecular biology results showed that the bone reconstruction was out-sync in each group. Compared with other groups, the bone resorption occurred at the latest and the bone resorption time was the shortest in experimental animals of SCPP group. All results indicated that SCPP could promote osteoblast activity and bone reconstruction, improve the integration of bone interface between prosthesis and base bone, reduce osteoclast activity and shorten the osteoclast action time at the implantation site in vivo. Thus, it could postpone or alleviate the occurrence and development of aseptic loosening in vivo. Therefore, SCPP could be a promising material for the construction of artificial joints with the ability to resist aseptic loosening.

Preparation, characterization, and feasibility study of Sr/Zn-doped CPP/GNS/UHMWPE composites as an artificial joint component with enhanced hardness, impact strength, tribological and biological performance.

In order to solve the problem of aseptic loosening of artificial joints resulting from the wear particles of artificial joint components in total joint replacement (TJR), we synthesized a new kind of metalo-organic particle (Sr/Zn-doped CPP/GNS) using spark plasma sintering (SPS) as a filler to enhance the comprehensive performance of UHMWPE. Sr/Zn-doped CPP/GNS was interfused evenly with UHMWPE particles and cured in a hot press instrument to prepare Sr/Zn-doped CPP/GNS/UHMWPE composites. FTIR and SEM were carried out to characterize Sr/Zn-doped CPP/GNS particles. EDS was carried out to characterize Sr/Zn-doped CPP/GNS/UHMWPE. The micro-structure, hardness, impact strength, tribology and bio-activities of Sr/Zn-doped CPP/GNS/UHMWPE composite materials were also investigated. The results confirmed the effectiveness of this method. The hardness, impact strength, and tribology of the composites were enhanced by adding homodispersed Sr/Zn-doped CPP/GNS particles into UHMWPE. In the meantime, Sr/Zn-doped CPP/GNS/UHMWPE composites could significantly promote the growth of osteoblasts due to the bio-activity of Sr/Zn-doped CPP/GNS. Furthermore, the addition of Sr/Zn-doped CPP/GNS particle-fillers into UHMWPE could promote the secretion of OPG from osteoblasts and inhibit the secretion of RANKL from osteoblasts, and thus increase the OPG/RANKL ratio. All the results above showed that Sr/Zn-doped CPP/GNS/UHMWPE composites with appropriate Sr/Zn-doped CPP/GNS content possessed superior physicochemical performances and bio-properties, and could be considered as promising materials to treat aseptic loosening in total joint replacement.

Concentration-Dependent Regulation of TiAl6V4 Particles on the Osteogenesis Potential of Human Bone Marrow Mesenchymal Stem Cells.

Total joint replacement is one of the most effective treatments for osteoarthritis, while the aseptic loosening of artificial joint is a major complication leading to the joint replacement failure. There are very limited studies about the effects of titanium-alloy particles on the osteogenic differentiation of mesenchymal stem cells. In this study, human bone marrow-derived mesenchymal stem cells (BM-hMSCs) were treated with different concentrations of TiAl6V4 particles. The cell viability was detected by MTT assay, and the cell proliferation was assessed by CKK-8 assay. The early and late stages of osteogenic differentiation were determined by alkaline phosphatase (ALP) and Alizarin Red S (ARS) staining assays. The expression of osteogenic genes and proteins was analyzed by RT-PCR and Western blot. TiAl6V4 particles at high concentration 100μg/ml inhibited the cell viability of BM-hMSCs. However, TiAl6V4 in the range of 5-50μg/ml did not show effects neither on the cell viability nor on the cell proliferation of BM-hMSCs. TiAl6V4 particles showed concentration-dependent bidirectional regulations on BM-hMSC osteogenesis. Specifically, TiAl6V4 at 5μg/ml promoted the osteogenesis of BM-hMSCs, which was suppressed by TiAl6V4 at 50μg/ml. Further, mechanism study revealed that the regulation of TiAl6V4 on BM-hMSCs was related to Wnt signaling pathway. Given the potential of mesenchymal cells, our study suggested that the minimization of metal use would be an attractive strategy to reduce the joint replacement failure.

Magnesium lithospermate B inhibits titanium particles-induced osteoclast formation by c-fos and inhibiting NFATc1 expression

ABSTRACTPurpose: Titanium particle-induced osteolysis is one of the important causes of aseptic loosening of artificial joints. Previous studies have shown the potential of natural compounds in preventing Ti particle-induced bone resorption. In this study, we observed the effects of magnesium lithospermate B (MLB) on titanium particle-induced osteoclast activity in vitro.Materials and Methods: RAW264.7 cells were treated with titanium particles (0.1 mg/mL) in the presence or absence of MLB (200 nmol/L). We evaluated the osteoclast formation, bone pits formation and tartrate-resistant acid phosphatase 5b (Tracp5b) levels. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to evaluate osteoclast differentiation-related genes (TRAF6, NFATc1, and c-fos) and protein expression.Results: The number of osteoclasts, pit formation and Tracp5b levels were all the group treated with titanium particles compared to the control group (all p < 0.05). Titanium particles also promoted the expression of the TRAF6, NFATc1 and c-fos genes and protein expression. MLB significantly abolished the titanium particle-enhanced osteoclast and pits formation, and Traf6, NFATc1, and c-fos expression.Conclusions: Our data demonstrated that MLB can suppress titanium-induced osteoclast activity via inhibiting c-fos and NFATc1 expression.

Targeting Anion Exchange of Osteoclast, a New Strategy for Preventing Wear Particles Induced- Osteolysis.

Joint replacement is essential for the treatment of serious joint disease. However, prosthetic failure remains an important clinical issue, with periprosthesis osteolysis (PO), caused by osteoclastic bone resorption induced by wear particles, being the leading cause of failure. Nuclear factor of activated T cells c1 (NFATc1) appears to play an important role in wear particle-induced osteoclastogenesis, with bicarbonate/chloride exchanger, solute carrier family 4, anion exchanger, member 2, (SLC4A2) being upregulated during osteoclastogenesis in an NFATc1-dependent manner. Anion exchange mediated by SLC4A2 in osteoclasts could affect the bone resorption activity by regulating pHi. This study investigated the role and mechanism of SLC4A2 in wear particle-induced osteoclast differentiation and function in vitro. The use of 4, 4′-diisothiocyano-2,2′-stilbenedisulfonic acid (DIDS), an anion exchange inhibitor, suppressed wear particle-induced PO in vivo. Furthermore, controlled release of DIDS from chitosan microspheres can strengthen the PO therapy effect. Therefore, anion exchange mediated by osteoclastic SLC4A2 may be a potential therapeutic target for the treatment of aseptic loosening of artificial joints.

Modification of Cysteine 179 in IKKβ by Ursolic Acid Inhibits Titanium-Wear-Particle-Induced Inflammation, Osteoclastogenesis, and Hydroxylapatite Resorption.

Aseptic loosening of artificial joints mainly accounts for the failure of arthroplasty. We previously reported that ursolic acid (UA) inhibited osteolysis caused by titanium (Ti) wear particles via suppression of NF-kB signaling. In the present study, that the suppressive effect of UA on Ti-particle-induced inflammation and osteoclastogenesis targets on IKKβ cys-179 was demonstrated. A retrovirus packaged IKKβC179A plasmid with a Cys-179 mutation replaced by Ala was constructed. qRT-PCR, immunoblot, and immunofluorescence were used to evaluate the gene expressions. Secreted inflammatory cytokines were detected by ELISA. Formation and function of osteoclastogenesis were evaluated by TRAP stain and hydroxylapatite resorption assays. As a result, a mutation of IKKβC179A rescued the therapeutic effect of UA on Ti-particle-induced inflammation, including morphological transforms, upregulation of iNOS and COX-2, increased secretions of TNF-α, IL-1β, and IL-6, and decreased secretion of IL-10. Meanwhile, inhibition of osteoclastogenesis and hydroxylapatite resorptions were restored by transfection of IKKβC179A. Phosphorylations of p65 and the IKKα/β complex and translocation of p65 into the nucleus were suppressed by UA but rescued by a mutation of IKKβC179A. Conclusively, UA inhibits Ti-wear-particle-induced inflammation, osteoclastogenesis, and hydroxylapatite resorption via modifying cysteine 179 of IKKβ.

Nano-sized titanium alloy particles inhibit the proliferation and promote the apoptosis of bone marrow mesenchymal stem cells invitro.

Aseptic loosening of artificial joints is the leading cause of failure for patients who receive total joint arthroplasty. Prior reports indicate that bone marrow mesenchymal stem cells (BSMC) are critical in the stabilization of implanted artificial joints, and that deregulated interaction between BMSCs and artificial joint derived particles is a risk factor for aseptic loosening with an unknown mechanism. In the present study, the pathomechanisms whereby titanium and its alloy derived particles facilitate aseptic loosing were investigated in vitro. It was demonstrated that nano-sized titanium alloy particles significantly inhibited the proliferation of BMSCs in a time and concentration dependent manner. Furthermore, it was demonstrated that the particles promoted the apoptosis of BMSCs in the same manner. Bax and Caspase-3 expression of BMSCs were elevated when cultured with the particles. As BMSCs exhibit a critical role in the stabilization of artificial joints, the results of the present study may provide a novel direction for the management of aseptic loosening in clinics.

Optimization of wear loss in silicon nitride (Si3N4)-hexagonal boron nitride (hBN) composite using DoE-Taguchi method.

Introduction The contacting surfaces subjected to progressive loss of material known as ‘wear,’ which is unavoidable between contacting surfaces. Similar kind of phenomenon observed in the human body in various joints where sliding/rolling contact takes place in contacting parts, leading to loss of material. This is a serious issue related to replaced joint or artificial joint.Case descriptionOut of the various material combinations proposed for artificial joint or joint replacement Si3N4 against Al2O3 is one of in ceramic on ceramic category. Minimizing the wear loss of Si3N4 is a prime requirement to avoid aseptic loosening of artificial joint and extending life of joint.Discussion and evaluationIn this paper, an attempt has been made to investigate the wear loss behavior of Si3N4–hBN composite and evaluate the effect of hBN addition in Si3N4 to minimize the wear loss. DoE–Taguchi technique is used to plan and analyze experiments.ConclusionAnalysis of experimental results proposes 15 N load and 8 % of hBN addition in Si3N4 is optimum to minimize wear loss against alumina.

The effect of titanium particles on the aseptic loosening of artificial joints

目的 分析不同直径、不同浓度的钛颗粒对人单核/巨噬细胞的作用.方法 应用梯度离心法分离人单核/巨噬细胞,去除钛颗粒表面的内毒素,将直径(15.47±5.18)μm和(2.54±0.86)μm的钛颗粒,分别以颗粒体积(μm3):细胞数比为10:1及100:1的浓度刺激人单核/巨噬细胞.在钛颗粒刺激细胞24 h后,运用ELISA检测培养上清液中的骨溶解介质白介素-1β(IL-1β)、白介素-6(IL-6)和细胞坏死因子-α(TNF-α)的浓度.结果 钛颗粒刺激单核/巨噬细胞可分泌IL-6、TNF-α和IL-1β;颗粒体积:细胞数比为100:1时,平均直径2.54μm的钛颗粒刺激单核/巨噬细胞产生IL-6、TNF-α和IL-1β的作用均大于直径15.47 μm的钛颗粒,差异有统计学意义(P＜0.05).结论 不含内毒素的钛颗粒本身具有刺激单核/巨噬细胞产生溶骨介质的作用;高浓度、直径小的钛颗粒可刺激人单核/巨噬细胞分泌更多的溶骨介质,具有较强的生物活性。

Enhancement of Differentiation and Homeostasis of Human Osteoblasts by Interaction with Hydroxyapatite in Microsphere Form

The aseptic loosening of artificial joints with associated periprosthetic bone resorption may be partly due to the suppression of osteoblast function to form new bone by wear debris derived from the joint. To assess the effect of wear debris on osteoblasts, we cultured normal human osteoblasts (NHOst) in contact with several kinds of microspheres as models of wear debris. The NHOst in contact with polystyrene, polyethylene, and alumina microspheres showed a lower differentiation level than NHOst alone as estimated from the amounts of deposited calcium. On the other hand, hydroxyapatite particles enhanced the differentiation of NHOst. In addition, sintered hydroxyapatite enhanced expression of osteocalcin mRNA and gap junctional communication of NHOst. This study suggests that polystyrene, polyethylene, and alumina microspheres have the potential to disorder not only the differentiation but also the homeostasis of NHOst in contact with them. However, hydroxyapatite enhanced the differentiation as well as the homeostasis of NHOst, even in microsphere form, suggesting its good biocompatibility as biomaterials for bone tissues.

Hydroxy apatite microspheres enhance gap junctional intercellular communication of human osteoblasts composed of connexin 43 and 45

The aseptic loosening of artificial joints with associated periprosthetic bone resorption may be partly due to the suppression of osteoblast function to form new bone by wear debris from the joint. To assess the effect of wear debris on osteoblasts, effects of model wear debris on gap junctional intercellular communication (GJIC) of normal human osteoblasts were estimated. The GJIC activity of the osteoblasts after a 1-day incubation with the microspheres was similar to that of normal osteoblasts. However, hydroxy apatite particles, which have been reported to enhance the differentiation of osteoblasts in contact with them, enhanced the GJIC function of the osteoblasts. From RT-PCR studies, not only connexin 43 but also connexin 45 is suggested to play a role in the GJIC of the osteoblasts in an early stage of coculture with the microspheres, although it is still unclear how these connexins work and are regulated in the GJIC and differentiation. However, this study suggests that there is a relationship between the early levels of GJIC and the differentiation of the cells. Therefore, estimating the effect of biomaterials, even in the microsphere form, on the GJIC of model cells, with which the biomaterials may be in contact in vivo, can provide important information about their biocompatibility.