Asunto(s)

Carbonato de Calcio , Osteoclastos , Osteoporosis , Ácido Zoledrónico , Ácido Zoledrónico/farmacología , Ácido Zoledrónico/uso terapéutico , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteoporosis/tratamiento farmacológico , Humanos , Carbonato de Calcio/química , Animales , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Materiales Biocompatibles/química , Nanopartículas/química

RESUMEN

Osteoporosis remains incurable. The most widely used antiresorptive agents, bisphosphonates (BPs), also inhibit bone formation, while the anabolic agent, teriparatide, does not inhibit bone resorption, and thus they have limited efficacy in preventing osteoporotic fractures and cause some side effects. Thus, there is an unmet need to develop dual antiresorptive and anabolic agents to prevent and treat osteoporosis. Hydroxychloroquine (HCQ), which is used to treat rheumatoid arthritis, prevents the lysosomal degradation of TNF receptor-associated factor 3 (TRAF3), an NF-κB adaptor protein that limits bone resorption and maintains bone formation. We attempted to covalently link HCQ to a hydroxyalklyl BP (HABP) with anticipated low antiresorptive activity, to target delivery of HCQ to bone to test if this targeting increases its efficacy to prevent TRAF3 degradation in the bone microenvironment and thus reduce bone resorption and increase bone formation, while reducing its systemic side effects. Unexpectedly, HABP-HCQ was found to exist as a salt in aqueous solution, composed of a protonated HCQ cation and a deprotonated HABP anion. Nevertheless, it inhibited osteoclastogenesis, stimulated osteoblast differentiation, and increased TRAF3 protein levels in vitro. HABP-HCQ significantly inhibited both osteoclast formation and bone marrow fibrosis in mice given multiple daily PTH injections. In contrast, HCQ inhibited marrow fibrosis, but not osteoclast formation, while the HABP alone inhibited osteoclast formation, but not fibrosis, in the mice. HABP-HCQ, but not HCQ, prevented trabecular bone loss following ovariectomy in mice and, importantly, increased bone volume in ovariectomized mice with established bone loss because HABP-HCQ increased bone formation and decreased bone resorption parameters simultaneously. In contrast, HCQ increased bone formation, but did not decrease bone resorption parameters, while HABP also restored the bone lost in ovariectomized mice, but it inhibited parameters of both bone resorption and formation. Our findings suggest that the combination of HABP and HCQ could have dual antiresorptive and anabolic effects to prevent and treat osteoporosis.

Asunto(s)

Conservadores de la Densidad Ósea , Resorción Ósea , Difosfonatos , Hidroxicloroquina , Ovariectomía , Animales , Ovariectomía/efectos adversos , Femenino , Ratones , Hidroxicloroquina/farmacología , Hidroxicloroquina/uso terapéutico , Difosfonatos/farmacología , Difosfonatos/uso terapéutico , Resorción Ósea/prevención & control , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Conservadores de la Densidad Ósea/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Ratones Endogámicos C57BL , Anabolizantes/farmacología , Anabolizantes/uso terapéutico , Osteogénesis/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Osteoporosis/prevención & control , Osteoporosis/metabolismo , Osteoporosis/patología , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo

RESUMEN

OBJECTIVE: The study will be to observe the effect of Sodium butyrate (NaB) on bone loss in lipopolysaccharide (LPS)-treated rats. METHODS: In the rat model, we observed that changes in the expression of oxidative stress regulators, inflammatory markers and target genes were measured by immunofluorescence and RT-PCR after treatment. Changes in viability and osteogenesis of MC3T3-E1, osteoclast differentiation in RAW264.7 cells in the presence of LPS were evaluated using CCK-8, ALP staining, RES staining, and TRAP staining. RESULTS: In vitro experiments have shown that LPS-induced inhibition of JC-1, SIRT1, GPX1 and SOD2 is associated with increased levels of inflammation and oxidative stress. In addition, NaB has been found to suppress oxidative stress, inflammation and Mito SOX, promote osteogenic differentiation, and inhibit osteoclast differentiation. In addition, NaB significantly promoted SITR1 expression, repaired impaired bone metabolism, and improved bone strength and bone mineral density. CONCLUSION: Given all this experimental evidence, the results strongly suggest that NaB can restore osteogenic activity in the presence of LPS by reducing intracellular ROS, inhibiting osteoclast differentiation and reducing bone loss in LPS-treated rat models.

Asunto(s)

Ácido Butírico , Inflamación , Lipopolisacáridos , Estrés Oxidativo , Animales , Lipopolisacáridos/toxicidad , Lipopolisacáridos/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratas , Ácido Butírico/farmacología , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Ratones , Células RAW 264.7 , Osteogénesis/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Diferenciación Celular/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Masculino , Ratas Sprague-Dawley , Huesos/efectos de los fármacos , Huesos/metabolismo

RESUMEN

Erythropoietin (EPO), expressed in red blood progenitor cells, primarily regulates erythropoiesis by binding to its receptor. Besides anemia, recent studies have identified new therapeutic indications for EPO that are not connected to red blood cell formation. Elevated EPO levels harm bone homeostasis in adult organisms and are associated with increased osteoclast; however, the underlying molecular mechanisms remain unclear. This study demonstrated that EPO enhanced osteoclast differentiation and bone resorption in vitro. We showed that EPO promoted osteoclast formation by up-regulating PPARγ expression through activating the Jak2/ERK signaling pathway. Consistently, PPARγ antagonists rescued the hyperactivation of osteoclasts due to EPO, while PPARγ agonists reversed the EMP9-mediated decrease in osteoclast differentiation. Further, exposing female mice to EPO for two months led to a decrease in bone mass and increased osteoclast numbers. The present results suggested that EPO promotes osteoclastogenesis by regulating the Jak2/ERK/ PPARγ signaling pathway. From a clinical perspective, the risk of compromised bone health should be considered when using EPO to treat anemia in post-operative patients with intertrochanteric fractures of the femur, as it could significantly impact the patient's recovery and quality of life.

Asunto(s)

Diferenciación Celular , Eritropoyetina , Osteoclastos , PPAR gamma , Eritropoyetina/farmacología , Eritropoyetina/metabolismo , Animales , PPAR gamma/metabolismo , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Ratones , Femenino , Diferenciación Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Janus Quinasa 2/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Humanos , Regulación hacia Arriba/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Resorción Ósea/metabolismo , Ratones Endogámicos C57BL

RESUMEN

Rheumatoid arthritis (RA) is a chronic autoimmune disease accompanied by local and systemic bone loss. FcγRs, especially FcγRIIa (hFcγRIIa), have been implicated in the pathogenesis of RA. However, the contribution of hFcγRIIa to bone loss has not been fully elucidated. In the present study, we demonstrated the double-edged sword role of hFcγRIIa on osteoclast differentiation through investigations involving hFcγRIIa-transgenic (hFcγRIIa-Tg) mice. Our findings reveal that hFcγRIIa-Tg mice, previously shown to exhibit heightened susceptibility to collagen-induced arthritis (CIA), displayed increased osteoporosis during CIA or at advanced ages (40 weeks), accompanied by heightened in vivo osteoclast differentiation. Notably, bone marrow cells from hFcγRIIa-Tg mice exhibited enhanced efficiency in differentiating into osteoclasts and bone resorption in vitro compared to wild-type mice when stimulated with receptor activators of NF-κB ligand (RANKL). Additionally, hFcγRIIa-Tg mice exhibited augmented sensitivity to RANKL-induced bone loss in vivo, highlighting the osteoclast-promoting role of hFcγRIIa. Mechanistically, bone marrow cells from hFcγRIIa-Tg mice displayed heightened Syk self-activation, leading to mTOR-pS6 pathway activation, thereby promoting RANKL-driven osteoclast differentiation. Intriguingly, while hFcγRIIa crosslinking hindered RANKL-induced osteoclast differentiation, it activated the kinase cAbl, subsequently triggering STAT5 activation and inhibiting the expression of osteoclast-associated genes. This study provides novel insights into hFcγRIIa-mediated osteoclast biology, suggesting promising therapeutic targets for managing bone remodeling disorders.

Asunto(s)

Resorción Ósea , Diferenciación Celular , Ratones Transgénicos , Osteoclastos , Osteogénesis , Receptores de IgG , Animales , Receptores de IgG/genética , Receptores de IgG/metabolismo , Ratones , Osteoclastos/metabolismo , Osteogénesis/genética , Resorción Ósea/genética , Resorción Ósea/metabolismo , Ligando RANK/metabolismo , Ligando RANK/genética , Artritis Experimental/inmunología , Artritis Experimental/genética , Transducción de Señal , Artritis Reumatoide/metabolismo , Artritis Reumatoide/inmunología , Artritis Reumatoide/genética , Osteoporosis/genética , Osteoporosis/etiología , Osteoporosis/metabolismo

RESUMEN

OBJECTIVES: To investigate whether the inhibition of 12/15-lipoxygenase (12/15-LOX), one of the core enzymes of the arachidonic acid cascade, suppresses orthodontically induced root resorption (OIRR), and examine the involvement of the hyaline degeneration of periodontal ligament cells and odontoclast differentiation. MATERIALS AND METHODS: The left maxillary first molars of 10-week-old male Wistar rats were moved mesially for 14 days using a closed-coil spring (25 cN) inserted between the first molar and incisor. The rats were intraperitoneally administered with a 12/15-LOX specific inhibitor (ML-351; 0.05 mmol/kg) daily in the experimental group or vehicle (dimethyl sulfoxide) in the control group. Tooth movement was measured using microcomputed tomography on day 14. The appearance of OIRR, hyaline degeneration, osteoclasts, and odontoclasts was evaluated via histological analysis. Immunohistochemical staining for receptor-activated NF-kB ligand (RANKL) and osteoprotegerin was performed. RESULTS: OIRR observed on day 14 in the control group was strongly suppressed by ML-351 treatment. Hyaline degeneration observed on the compression side on day 3 and the appearance of osteoclasts and odontoclasts on days 3 and 14 were significantly suppressed by ML-351. RANKL expression on day 3 was significantly suppressed by ML-351. These key processes in OIRR were substantially suppressed by ML-351 treatment. CONCLUSIONS: Inhibition of 12/15-LOX reduced OIRR by suppressing hyaline degeneration and subsequent odontoclast differentiation.

Asunto(s)

Araquidonato 12-Lipooxigenasa , Araquidonato 15-Lipooxigenasa , Inhibidores de la Lipooxigenasa , Osteoclastos , Ratas Wistar , Resorción Radicular , Técnicas de Movimiento Dental , Animales , Masculino , Técnicas de Movimiento Dental/métodos , Resorción Radicular/etiología , Resorción Radicular/prevención & control , Resorción Radicular/patología , Ratas , Araquidonato 15-Lipooxigenasa/metabolismo , Araquidonato 12-Lipooxigenasa/metabolismo , Inhibidores de la Lipooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/uso terapéutico , Osteoclastos/efectos de los fármacos , Microtomografía por Rayos X , Ligando RANK/metabolismo , Diferenciación Celular/efectos de los fármacos , Ligamento Periodontal/efectos de los fármacos , Ligamento Periodontal/patología , Osteoprotegerina/metabolismo , Diente Molar

RESUMEN

G protein-coupled receptor (GPR)40 and GPR120 are receptors for medium- and long-chain free fatty acids. It has been well documented that GPR40 and GPR120 activation improves metabolic syndrome (MetS) and exerts anti-inflammatory effects. Since chronic periodontitis is a common oral inflammatory disease initiated by periodontal pathogens and exacerbated by MetS, we determined if GPR40 and GPR120 activation with agonists improves MetS-associated periodontitis in animal models in this study. We induced MetS and periodontitis by high-fat diet feeding and periodontal injection of lipopolysaccharide, respectively, and treated mice with GW9508, a synthetic GPR40 and GPR120 dual agonist. We determined alveolar bone loss, osteoclast formation, and periodontal inflammation using micro-computed tomography, osteoclast staining, and histology. To understand the underlying mechanisms, we further performed studies to determine the effects of GW9508 on osteoclastogenesis and proinflammatory gene expression in vitro. Results showed that GW9508 improved metabolic parameters, including glucose, lipids, and insulin resistance. Results also showed that GW9508 improves periodontitis by reducing alveolar bone loss, osteoclastogenesis, and periodontal inflammation. Finally, in vitro studies showed that GW9508 inhibited osteoclast formation and proinflammatory gene secretion from macrophages. In conclusion, this study demonstrated for the first time that GPR40/GPR120 agonist GW9508 reduced alveolar bone loss and alleviated periodontal inflammation in mice with MetS-exacerbated periodontitis, suggesting that activating GPR40/GPR120 with agonist GW9508 is a potential anti-inflammatory approach for the treatment of MetS-associated periodontitis.

Asunto(s)

Síndrome Metabólico , Metilaminas , Periodontitis , Propionatos , Receptores Acoplados a Proteínas G , Animales , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Ratones , Síndrome Metabólico/tratamiento farmacológico , Síndrome Metabólico/metabolismo , Síndrome Metabólico/complicaciones , Propionatos/farmacología , Propionatos/uso terapéutico , Periodontitis/tratamiento farmacológico , Periodontitis/metabolismo , Metilaminas/farmacología , Masculino , Ratones Endogámicos C57BL , Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/etiología , Dieta Alta en Grasa/efectos adversos , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Modelos Animales de Enfermedad , Osteogénesis/efectos de los fármacos

RESUMEN

BACKGROUND: Bone regeneration is a well-regulated dynamic process, of which the prominent role of the immune system on bone homeostasis is more and more revealed by recent research. Before fully activation of the bone remodeling cells, the immune system needs to clean up the microenvironment in facilitating the bone repair initiation. Furthermore, this microenvironment must be maintained properly by various mechanisms over the entire bone regeneration process. OBJECTIVE: This review aims to summarize the role of the T-helper 17/Regulatory T cell (Th17/Treg) balance in bone cell remodeling and discuss the relevant progress in bone tissue engineering. RESULTS: The role of the immune response in the early stages of bone regeneration is crucial, especially the impact of the Th17/Treg balance on osteoclasts, mesenchymal stem cells (MSCs), and osteoblasts activity. By virtue of these knowledge advancements, innovative approaches in bone tissue engineering, such as nano-structures, hydrogel, and exosomes, are designed to influence the Th17/Treg balance and thereby augment bone repair and regeneration. CONCLUSION: Targeting the Th17/Treg balance is a promising innovative strategy for developing new treatments to enhance bone regeneration, thus offering potential breakthroughs in bone injury clinics.

Asunto(s)

Regeneración Ósea , Huesos , Linfocitos T Reguladores , Células Th17 , Ingeniería de Tejidos , Humanos , Linfocitos T Reguladores/inmunología , Ingeniería de Tejidos/métodos , Regeneración Ósea/inmunología , Animales , Células Th17/inmunología , Huesos/inmunología , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/metabolismo , Remodelación Ósea/inmunología , Osteoblastos/inmunología , Osteoclastos/inmunología , Osteoclastos/metabolismo

RESUMEN

This study explored the mechanism of curcumin (CUR) suppressing osteoclastogenesis and evaluated its effects on osteoarthritis (OA) mouse. Bone marrow-derived macrophages were isolated as osteoclast precursors. In the presence or absence of CUR, cell proliferation was detected by CCK-8, osteoclastogenesis was detected by tartrate-resistant acid phosphatase (TRAP) staining, F-actin rings formation was detected by immunofluorescence, bone resorption was detected by bone slices, IκBα, nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were detected using western blot, osteoclastogenesis-related gens were measured using quantitative polymerase chain reaction. A knee OA mouse model was designed by destabilizing the medial meniscus (DMM). Thirty-six male mice were divided into sham+vehicle, OA+vehicle, and OA+CUR groups. Mice were administered with or without CUR at 25 mg/kg/d from the first post-operative day until sacrifice. After 4 and 8 weeks of OA induction, micro-computed tomography was performed to analyze microstructure changes in subchondral bone, hematoxylin and eosin staining was performed to calculate the thickness of the calcified and hyaline cartilage layers, toluidine blue O staining was performed to assess the degenerated cartilage, TRAP-stained osteoclasts were counted, and NF-κB, phosphorylated Jun N-terminal Kinases (p-JNK), and receptor activator of nuclear factor κB ligand (RANKL) were detected using immunohistochemistry. CUR suppressed osteoclastogenesis and bone resorption without cytotoxicity. CUR restrained RANKL-induced activation of NF-κB, p-JNK and up-regulation of osteoclastogenesis-related genes. CUR delayed cartilage degeneration by suppressing osteoclastogenesis and bone resorption in early OA. The mechanism of CUR inhibiting osteoclastogenesis might be associated with NF-κB/JNK signaling pathway, indicating a novel strategy for OA treatment.

Asunto(s)

Curcumina , Sistema de Señalización de MAP Quinasas , FN-kappa B , Osteoclastos , Osteogénesis , Animales , Ratones , Masculino , FN-kappa B/metabolismo , Curcumina/farmacología , Osteogénesis/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Osteoartritis/patología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Resorción Ósea/patología

RESUMEN

Developing bones can adapt their shape in response to mechanical stresses from neighbouring growing organs. In a new study, Koichi Matsuo and colleagues examine how bone-forming osteoblasts and bone-resorbing osteoclasts coordinate growth in the mouse fibula. They describe the process called 'endo-forming trans-pairing', where bone resorption by osteoclasts in the outer periosteum is paired with bone formation by osteoblasts in the inner endosteum to shape the growing bone. To learn more about the story behind the paper, we caught up with first author Yukiko Kuroda and the corresponding author Koichi Matsuo, Professor at the School of Medicine, Keio University, Japan.

Asunto(s)

Huesos , Microscopía/métodos , Huesos/citología , Osteoclastos/citología , Osteoclastos/metabolismo , Osteoblastos/citología , Osteoblastos/metabolismo , Nervio Ciático , Desarrollo Óseo , Animales , Morfogénesis

RESUMEN

BACKGROUND: Zoledronic acid (ZOL) is a type of bisphosphonate with good therapeutic effects on orthopaedic diseases. However, the pharmacological functions of ZOL on steroid-induced avascular necrosis of femoral head (SANFH) and the underlying mechanism remain unclear, which deserve further research. METHODS: SANFH models both in vivo and in vitro were established by dexamethasone (Dex) stimulation. Osteoclastogenesis was examined by TRAP staining. Immunofluorescence was employed to examine autophagy marker (LC3) level. Cell apoptosis was analyzed by TUNEL staining. The interaction between Foxhead box D3 protein (FOXD3) and Annexin A2 (ANXA2) promoter was analyzed using ChIP and dual luciferase reporter gene assays. RESULTS: Dex aggravated osteoclastogenesis and induced osteoclast differentiation and autophagy in vitro, which was abrogated by ZOL treatment. PI3K inhibitor LY294002 abolished the inhibitory effect of ZOL on Dex-induced osteoclast differentiation and autophagy. FOXD3 overexpression neutralized the downregulation effects of ZOL on Dex-induced osteoclasts by transcriptionally activating ANXA2. ANXA2 knockdown reversed the effect of FOXD3 overexpression on ZOL-mediated biological effects in Dex-treated osteoclasts. In addition, ZOL improved SANFH symptoms in rats. CONCLUSION: ZOL alleviated SANFH through regulating FOXD3 mediated ANXA2 transcriptional activity and then promoting PI3K/AKT/mTOR pathway, revealing that FOXD3 might be a target for ZOL in SANFH treatment.

Asunto(s)

Anexina A2 , Autofagia , Necrosis de la Cabeza Femoral , Factores de Transcripción Forkhead , Activación Transcripcional , Ácido Zoledrónico , Animales , Necrosis de la Cabeza Femoral/inducido químicamente , Necrosis de la Cabeza Femoral/patología , Necrosis de la Cabeza Femoral/genética , Necrosis de la Cabeza Femoral/tratamiento farmacológico , Ácido Zoledrónico/farmacología , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Autofagia/efectos de los fármacos , Autofagia/genética , Anexina A2/metabolismo , Anexina A2/genética , Masculino , Activación Transcripcional/efectos de los fármacos , Dexametasona/farmacología , Dexametasona/efectos adversos , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteoclastos/patología , Diferenciación Celular/efectos de los fármacos , Ratones , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Apoptosis/efectos de los fármacos , Ratas , Ratas Sprague-Dawley

RESUMEN

Tartrate-resistant acid phosphatase (TRAP) serum levels reflect osteoclast number, bone remodeling activity, and fracture risk. Deletion or loss of function of TRAP results in short stature in mice and man. Yet, the impact and mechanisms of TRAP for the site- and sex-specific development of bone and cartilage is not well understood. Here, we use a global TRAP knockout (TRAPKO) and wildtype littermate control (WT) mice of both sexes to investigate TRAP as a possible sex- and site-specific regulator of bone and growth plate development. TRAPKO mice of both sexes weighed less and had shorter tibial length than their WT, features that were more accentuated in male than female TRAPKO mice. These changes were not associated with a general reduction in growth as not all organs displayed a proportionally lower mass, and serum IGF-1 was unchanged. Using µCT and site-specificity analysis of the cortical bone revealed wider proximal tibia, a higher trabecular thickness, and lower trabecular separation in male TRAPKO compared to WT mice, an effect not seen in female mice. Histomorphometric analysis revealed that the growth plate height as well as height of terminal hypertrophic chondrocytes were markedly increased, and the number of columns was decreased in TRAPKO mice of both sexes. These effects were more accentuated in female mice. Proliferation and differentiation of bone marrow derived macrophages into osteoclasts, as well as C-terminal cross links were normal in TRAPKO mice of both sexes. Collectively, our results show that TRAP regulates bone and cartilage development in a sex-and site-specific manner in mice.

Asunto(s)

Hueso Esponjoso , Hueso Cortical , Placa de Crecimiento , Ratones Noqueados , Caracteres Sexuales , Fosfatasa Ácida Tartratorresistente , Animales , Fosfatasa Ácida Tartratorresistente/metabolismo , Femenino , Masculino , Ratones , Osteoclastos/metabolismo , Tamaño de los Órganos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Tibia/metabolismo , Microtomografía por Rayos X , Ratones Endogámicos C57BL

RESUMEN

Developing long bones alter their shape while maintaining uniform cortical thickness via coordinated activity of bone-forming osteoblasts and bone-resorbing osteoclasts at periosteal and endosteal surfaces, a process we designate trans-pairing. Two types of trans-pairing shift cortical bone in opposite orientations: peri-forming trans-pairing (peri-t-p) increases bone marrow space and endo-forming trans-pairing (endo-t-p) decreases it, via paired activity of bone resorption and formation across the cortex. Here, we focused on endo-t-p in growing bones. Analysis of endo-t-p activity in the cortex of mouse fibulae revealed osteoclasts under the periosteum compressed by muscles, and expression of RANKL in periosteal cells of the cambium layer. Furthermore, mature osteoblasts were localized on the endosteum, while preosteoblasts were at the periosteum and within cortical canals. X-ray tomographic microscopy revealed the presence of cortical canals more closely associated with endo- than with peri-t-p. Sciatic nerve transection followed by muscle atrophy and unloading induced circumferential endo-t-p with concomitant spread of cortical canals. Such canals likely supply the endosteum with preosteoblasts from the periosteum under endo-t-p, allowing bone shape to change in response to mechanical stress or nerve injury.

Asunto(s)

Osteoblastos , Osteoclastos , Periostio , Animales , Osteoblastos/metabolismo , Osteoblastos/citología , Periostio/citología , Periostio/metabolismo , Osteoclastos/metabolismo , Osteoclastos/citología , Ratones , Desarrollo Óseo , Osteogénesis/fisiología , Resorción Ósea/patología , Hueso Cortical , Ligando RANK/metabolismo , Ratones Endogámicos C57BL

RESUMEN

Osteoarthritis (OA) is a chronic degenerative disease characterized by articular cartilage destruction and subchondral bone reconstruction in the early stages. Bergenin (Ber) is a cytoprotective polyphenol found in many medicinal plants. It has been proven to have anti-inflammatory, antioxidant, and other biological activities, which may reveal its potential role in the treatment of OA. This study aimed to determine the potential efficacy of Ber in treating OA and explore the possible underlying mechanism through network pharmacology and validation experiments. The potential co-targets and processes of Ber and OA were predicted by using network pharmacology, including a Venn diagram for intersection targets, a protein‒protein interaction (PPI) network to obtain key potential targets, and GO and KEGG pathway enrichment to reveal the probable mechanism of action of Ber on OA. Subsequently, validation experiments were carried out to investigate the effects and mechanisms of Ber in treating OA in vitro and vivo. Ber suppressed IL-1ß-induced chondrocyte apoptosis and extracellular matrix catabolism by inhibiting the STAT3, NF-κB and Jun signalling pathway in vitro. Furthermore, Ber suppressed the expression of osteoclast marker genes and RANKL-induced osteoclastogenesis. Ber alleviated the progression of OA in DMM-induced OA mice model. These results demonstrated the protective efficacy and potential mechanisms of Ber against OA, which suggested that Ber could be adopted as a potential therapeutic agent for treating OA.

Asunto(s)

Benzopiranos , Condrocitos , FN-kappa B , Osteoartritis , Osteoclastos , Osteogénesis , Factor de Transcripción STAT3 , Transducción de Señal , Factor de Transcripción STAT3/metabolismo , Animales , Osteoartritis/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/patología , Osteoartritis/prevención & control , FN-kappa B/metabolismo , Benzopiranos/farmacología , Ratones , Transducción de Señal/efectos de los fármacos , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/efectos de los fármacos , Masculino , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Ratones Endogámicos C57BL , Mapas de Interacción de Proteínas/efectos de los fármacos

RESUMEN

The onset of osteonecrosis of the femoral head (ONFH) is intimately associated with the extensive administration of glucocorticoids (GCs). Long-term stimulation of GCs can induce oxidative stress in both osteoclasts (OCs) and osteoblasts (OBs), resulting in the disturbance of bone remodelling. An alkaloid named crebanine (CN) demonstrates pharmacological properties including anti-inflammation and reactive oxygen species (ROS) modulation. Our objective is to assess the therapeutic potential of CN in treating ONFH and elucidate the associated underlying mechanisms. The network pharmacology analysis uncovered that CN played a role in regulating ROS metabolism. In vitro, CN demonstrated its ability to reduce the dexamethasone (DEX)-stimulated generation of OCs and suppress their resorptive function by downregulating the level of osteoclast marker genes. Concurrently, CN also mitigated DEX-induced damage to OBs, facilitating the restoration of osteoblast marker gene expression, cellular differentiation and function. These effects were achieved by CN augmenting the antioxidant system to reduce intracellular ROS levels. Furthermore, in vitro results were corroborated by micro-CT and histological data, which also showed that CN attenuated MPS-induced ONFH in mice. This study highlights the therapeutic potential of CN in counteracting GCs-induced ONFH.

Asunto(s)

Remodelación Ósea , Necrosis de la Cabeza Femoral , Glucocorticoides , Osteoblastos , Osteoclastos , Estrés Oxidativo , Especies Reactivas de Oxígeno , Animales , Estrés Oxidativo/efectos de los fármacos , Glucocorticoides/efectos adversos , Glucocorticoides/farmacología , Remodelación Ósea/efectos de los fármacos , Ratones , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Necrosis de la Cabeza Femoral/inducido químicamente , Necrosis de la Cabeza Femoral/tratamiento farmacológico , Necrosis de la Cabeza Femoral/metabolismo , Necrosis de la Cabeza Femoral/patología , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Homeostasis/efectos de los fármacos , Dexametasona/farmacología , Dexametasona/efectos adversos , Masculino , Cabeza Femoral/patología , Cabeza Femoral/metabolismo , Cabeza Femoral/efectos de los fármacos , Modelos Animales de Enfermedad , Diferenciación Celular/efectos de los fármacos , Ratones Endogámicos C57BL , Humanos

RESUMEN

Introduction: In the process of bone regeneration, a prominent role is played by macrophages involved in both the initial inflammation and the regeneration/vascularization phases, due to their M2 anti-inflammatory phenotype. Together with osteoclasts, they participate in the degradation of the bone matrix if the inflammatory process does not end. In this complex scenario, recently, much attention has been paid to extracellular communication mediated by nanometer-sized vesicles, with high information content, called exosomes (EVs). Considering these considerations, the purpose of the present work is to demonstrate how the presence of a pulsed electromagnetic field (PEMF) can positively affect communication through EVs. Methods: To this aim, macrophages and osteoclasts were treated in vitro with PEMF and analyzed through molecular biology analysis and by electron microscopy. Moreover, EVs produced by macrophages were characterized and used to verify their activity onto osteoclasts. Results: The results confirmed that PEMF not only reduces the inflammatory activity of macrophages and the degradative activity of osteoclasts but that the EVS produced by macrophages, obtained from PEMF treatment, positively affect osteoclasts by reducing their activity. Discussion: The co-treatment of PEMF with M2 macrophage-derived EVs (M2-EVs) decreased osteoclastogenesis to a greater degree than separate treatments.

Asunto(s)

Regeneración Ósea , Campos Electromagnéticos , Exosomas , Macrófagos , Osteoclastos , Osteogénesis , Exosomas/química , Exosomas/metabolismo , Regeneración Ósea/efectos de la radiación , Regeneración Ósea/fisiología , Animales , Ratones , Osteogénesis/fisiología , Osteogénesis/efectos de la radiación , Células RAW 264.7

RESUMEN

BACKGROUND: It is well-known that oral surgical procedures pose a high risk for medication-related osteonecrosis of the jaw in patients taking bisphosphonates. Although some position papers and guidelines have been published with regard to its treatment, few studies have investigated prevention methods. This study investigates the effectiveness of methenolone enanthate, an anabolic steroid, for the prevention of medication-related osteonecrosis of the jaw. METHODS: Thirty-six Wistar rats were divided into three groups. Two experimental groups, Z and ZM, took zoledronic acid for 6 weeks prior to extraction of the left maxillary first molar. The Group ZM also was given methenolone enanthate continuously for 1 week before and 4 weeks after the extraction. The control group was not given any medication. The rats were euthanized 5 weeks after extraction. The extraction socket was evaluated clinically for bone exposure and histologically for inflammation, hyperemia, collagen fibers, epithelialization, number of osteoclasts, and empty lacunae. RESULTS: Six rats died during the experimental research. The bone exposure rate, mean numbers of attached osteoclasts (in 40× magnification), and empty lacunae (in 100× magnification) were 0%, 4%, and 0.8% in Group C; 75%, 1%, and 8% in Group Z; and 10%, 2.1%, and 3% in Group ZM, respectively. Significant differences exist between all groups regarding the number of empty lacunae. There were significant differences between Group C/ZM and Group Z in terms of bone exposure rate, inflammation, hyperemia, collagen fiber organization, and epithelialization. CONCLUSION: In our tested preclinical model, methenolone enanthate has shown potential for preventing medication-related osteonecrosis of the jaw.

Asunto(s)

Osteonecrosis de los Maxilares Asociada a Difosfonatos , Ratas Wistar , Animales , Ratas , Osteonecrosis de los Maxilares Asociada a Difosfonatos/prevención & control , Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Masculino , Ácido Zoledrónico/uso terapéutico , Extracción Dental , Distribución Aleatoria , Osteoclastos/efectos de los fármacos , Imidazoles/farmacología , Anabolizantes/uso terapéutico , Diente Molar , Difosfonatos/farmacología , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Alveolo Dental/efectos de los fármacos

RESUMEN

Bone-forming osteoblasts, osteocytes, and bone-resorbing osteoclasts are responsible for life-long skeletal remodeling [...].

Asunto(s)

Osteoblastos , Osteoclastos , Osteocitos , Humanos , Osteoblastos/metabolismo , Osteoblastos/citología , Osteoclastos/metabolismo , Osteoclastos/citología , Osteocitos/metabolismo , Osteocitos/citología , Animales , Huesos/citología , Huesos/metabolismo , Huesos/patología , Remodelación Ósea , Enfermedades Óseas/patología , Enfermedades Óseas/metabolismo

RESUMEN

BACKGROUND AND OBJECTIVE: The objective of this study was to investigate the potential of salidroside (SAL) (a major active compound in Rhodiola rosea L.) in regulating osteoclast differentiation and function by modulating the HIF-1α pathway and its downstream target genes. METHODS: The expression of HIF-1α and its downstream target genes was examined at both mRNA and protein levels in osteoclasts treated with SAL. Immunofluorescence analysis was performed to assess the nuclear translocation and transcriptional activity of HIF-1α in response to SAL. MTT, flow cytometry, qPCR, TRAP staining and bone resorption assays were used to evaluate the potential effect of salidroside on osteoclasts. RESULTS: SAL enhanced the expression of HIF-1α and its downstream target genes in osteoclasts. Immunofluorescence analysis confirmed the facilitation of HIF-1α nuclear translocation and transcriptional activity by SAL. In addition, SAL enhanced osteoclast viability, differentiation and bone resorption activity in an autocrine manner through HIF-1α/VEGF, IL-6 and ANGPTL4 pathways. CONCLUSION: SAL promotes osteoclast proliferation, differentiation and bone resorption through HIF-1α/VEGF, IL-6 and ANGPTL4 pathways.

Asunto(s)

Glucósidos , Subunidad alfa del Factor 1 Inducible por Hipoxia , Osteoclastos , Osteogénesis , Fenoles , Glucósidos/farmacología , Fenoles/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Osteoclastos/efectos de los fármacos , Animales , Ratones , Osteogénesis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Células RAW 264.7 , Interleucina-6/metabolismo , Interleucina-6/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Resorción Ósea , Transducción de Señal/efectos de los fármacos , Proteína 4 Similar a la Angiopoyetina/metabolismo , Proteína 4 Similar a la Angiopoyetina/genética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos

RESUMEN

Osteoporosis (OP) is a disorder of bone remodeling caused by an imbalance between bone resorption by osteoclasts and bone formation by osteoblasts. Therefore, inhibiting excessive osteoclast activity is one of the promising strategies for treating OP. A major transient receptor potential cation channel, known as transient receptor potential ankyrin 1 (TRPA1), was found to alleviate joint pain and cartilage degeneration in osteoarthritis. However, little research has focused on TRPA1 function in OP. As a result, this study aimed to explore the TRPA1 characteristics and its potential therapeutic function during osteoclastogenesis. The TRPA1 expression gradually increased in the osteoclast differentiation process; however, its suppression with small interfering RNA and an inhibitor (HC030031) significantly controlled the osteoclast count and the expression of osteoclast characteristic genes. Its suppression also inhibited endoplasmic reticulum (ER) stress-related pancreatic ER kinase (PERK) pathways. An ER stress inhibitor (thapsigargin) reversed the down-regulated levels of ER stress and osteoclast differentiation by suppressing TRPA1. Transcriptome sequencing results demonstrated that TRPA1 negatively regulated reactive oxygen species (ROS) and significantly increased the expression of an antioxidant gene, SRXN1. The osteoclast differentiation and the levels of ER stress were enhanced with SRXN1 inhibition. Finally, TRPA1 knockdown targeting macrophages by adeno-associated virus-9 could relieve osteoclast differentiation and osteopenia in ovariectomized mice. In summary, silencing TRPA1 restrained osteoclast differentiation through ROS-mediated down-regulation of ER stress via inhibiting PERK pathways. The study also indicated that TRPA1 might become a prospective treatment target for OP.

Asunto(s)

Diferenciación Celular , Estrés del Retículo Endoplásmico , Osteoclastos , Osteogénesis , Osteoporosis , Canal Catiónico TRPA1 , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Animales , Osteoporosis/metabolismo , Osteoporosis/patología , Osteoporosis/genética , Ratones , Osteoclastos/metabolismo , Osteogénesis/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo