RESUMEN
The Rank-Rankl-Opg axis is a fundamental regulatory triad in bone development and remodelling. While extensively studied, novel modulators of this system continue to emerge, with the transcription factor Myb recently gaining attention due to its unexpected presence and physiological significance in tooth and bone, beyond its well-established role in haematopoiesis. To establish a baseline for normal development, we first elucidated the developmental dynamics of Rankl and Opg expression during prenatal mandibular development and osteocytogenesis in wild-type mice within distinct morphological regions of the developing mandible (incisor, diastema, molar), revealing intricate temporal expression patterns. Building upon this foundational understanding, we then investigated the hitherto uncharacterized impact of Myb deficiency on Rankl and Opg expression at their survival limit (prenatal day 15), using Myb knock-out mice. We observed a significant and region-specific upregulation of both Rankl and Opg expression in the molar region of Myb-deficient mandibles, as assessed by qPCR. Intriguingly, increased expression of both genes was also evident in the incisor region, while no significant changes were noted within the diastema. In contrast, Rank expression remained unaffected across all three segments. To confirm the reciprocal effect of Myb, we demonstrated that its overexpression in mandibular micromasses reciprocally altered Rankl and Opg expression. By confronting the established developmental dynamics with the effects of Myb deficiency and Myb's own expression pattern, we provide compelling evidence for a potent and direct influence of Myb on Rankl and Opg regulation, particularly prominent in the molar region. The observed temporal peaks of Myb and Rankl expression at the osteoblast-osteocyte transition further suggest broader, pivotal roles for Myb in osteogenesis. Our findings unravel Myb as a critical orchestrator of the Rank-Rankl-Opg system in craniofacial bone development, opening new avenues for understanding bone dysregulation.
Asunto(s)
Mandíbula , Osteoprotegerina , Proteínas Proto-Oncogénicas c-myb , Ligando RANK , Animales , Ligando RANK/genética , Ligando RANK/metabolismo , Mandíbula/embriología , Mandíbula/metabolismo , Mandíbula/crecimiento & desarrollo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas c-myb/genética , Proteínas Proto-Oncogénicas c-myb/deficiencia , Regulación del Desarrollo de la Expresión Génica , Ratones Endogámicos C57BLRESUMEN
Ubiquitin-specific protease 7 (USP7), a member of the ubiquitin-specific protease (USP) family, functions as a deubiquitinating enzyme (DUB) and modulates transcriptional activity through interactions with various transcription factors. However, its role in osteoclastogenesis and the underlying molecular mechanisms remain incompletely understood. In this study, we demonstrate that USP7 is significantly upregulated during osteoclast differentiation and exhibits a negative correlation with osteoporosis. Genetic deletion of USP7 enhances osteoclast differentiation and bone resorption both in vitro and in vivo, whereas USP7 overexpression exerts inhibitory effects on these processes under similar experimental conditions. Moreover, USP7 deficiency promotes osteoclastogenesis and reduces bone mass in both normal and ovariectomized adult mice. Mechanistically, we observed hyperactivation of the nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK)signaling pathways in USP7-deficient bone marrow-derived macrophages (BMMs). In contrast, USP7 overexpression significantly attenuates the receptor activator of NF-κB ligand (RANKL)-induced activation of these pathways. Additionally, our findings reveal that USP7 participates in the regulation of the kelch-like ECH associated protein 1 (Keap1) -nuclear factor erythroid 2-related factor 2 (Nrf2) signaling axis. USP7 knockout results in elevated intracellular reactive oxygen species (ROS) levels, while USP7 overexpression effectively reduces ROS accumulation. Collectively, these results suggest that USP7 regulates osteoclast differentiation via modulation of the NF-κB/MAPK and Nrf2 signaling pathways, thereby influencing the progression of osteoporosis.
Asunto(s)
Proteínas de la Membrana , Factor 2 Relacionado con NF-E2 , FN-kappa B , Osteoclastos , Osteogénesis , Osteoporosis , Peptidasa Específica de Ubiquitina 7 , Animales , Factor 2 Relacionado con NF-E2/metabolismo , FN-kappa B/metabolismo , Osteogénesis/genética , Osteoclastos/fisiología , Transducción de Señal , Ratones , Peptidasa Específica de Ubiquitina 7/genética , Peptidasa Específica de Ubiquitina 7/metabolismo , Femenino , Ratones Noqueados , Diferenciación Celular , Ratones Endogámicos C57BL , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Osteoporosis/genética , Resorción Ósea/genética , Proteínas de la Membrana/metabolismo , Células Cultivadas , Humanos , Ligando RANK/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Hemo-Oxigenasa 1RESUMEN
The meninges, located between the skull and brain, harbor immune cells that monitor the brain borders. Skull marrow communicates with the meninges via bone channels, enabling immune-cell trafficking, but little is known about bone channel formation and modulation. We found that bone channels were formed during the perinatal stage in mice, and we developed approaches to modulate them and assess their impact on meningeal immunity. Myeloid cell depletion with anti-colony-stimulating factor 1 receptor (αCSF1R) or targeted osteoclast inhibition with anti-receptor activator of nuclear factor kappa-B ligand (αRANKL) reduced channel size, whereas mechanoreceptor transient receptor potential vanilloid 4 (TRPV4)-driven bone remodeling enlarged them. Following channel manipulation, lymphocytic choriomeningitis virus (LCMV) infection showed reduced meningeal immune infiltration in αRANKL-treated mice and increased infiltration with TRPV4 activation. In an ex vivo skull assay, restricting channels impaired skull-derived immune-cell migration to the meninges, whereas enhancing remodeling promoted it. Our findings reveal that bone remodeling controls the skull-to-meninges axis and highlight its role in immune-cell migration into the meninges during neuroinflammation.
Asunto(s)
Remodelación Ósea , Meninges , Enfermedades Neuroinflamatorias , Cráneo , Animales , Meninges/inmunología , Meninges/metabolismo , Ratones , Cráneo/inmunología , Cráneo/metabolismo , Remodelación Ósea/inmunología , Canales Catiónicos TRPV/metabolismo , Enfermedades Neuroinflamatorias/inmunología , Enfermedades Neuroinflamatorias/metabolismo , Ratones Endogámicos C57BL , Osteoclastos/inmunología , Osteoclastos/metabolismo , Movimiento Celular/inmunología , Ligando RANK/metabolismo , Coriomeningitis Linfocítica/inmunología , Virus de la Coriomeningitis Linfocítica/inmunologíaRESUMEN
This study investigated whether fermented mealworms extract (FME) can simultaneously improve postmenopausal osteoporosis and muscle atrophy, along with the underlying mechanisms. Female C57BL/6 N mice were divided into five groups: sham-operated, ovariectomized (OVX), OVX treated with two doses of FME (200 and 500 mg/kg, oral), and OVX treated with alendronate (Alen, 500 µg/kg, oral) as a positive control, for 15 weeks. FME500 significantly increased grip strength, whereas FME200 showed no significant improvement compared to the OVX group. Muscle cross-sectional area significantly increased in both FME groups compared to the OVX group. FME500 also enhanced muscle protein synthesis markers (MyoD1 and MHC) and more effectively suppressed muscle degradation markers (MuRF-1, atrogin-1, myostatin, and polyubiquitinated proteins) than FME200. In bone, both FME doses improved bone density and serum levels of RANKL and CTX-1 compared to the OVX group. FME500 more effectively downregulated RANKL, IL-6, and TNF-α expression in both bone and muscle than FME200 in OVX group. Mechanistic analyses were performed mainly in the FME500 group, which downregulated NFκB/MAPK and upregulated IGF-1-PI3K-Akt in both bone and muscle. These results indicate that FME suppresses the postmenopausal concurrent bone and muscle loss by regulating RANKL-NFκB/MAPK and IGF-1-PI3K-Akt signaling pathways.
Asunto(s)
Huesos , Mezclas Complejas , Fermentación , Sistema de Señalización de MAP Quinasas , FN-kappa B , Ovariectomía , Ligando RANK , Transducción de Señal , Animales , Femenino , FN-kappa B/metabolismo , Ligando RANK/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Ratones , Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/patología , Atrofia Muscular/prevención & control , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/patología , Mezclas Complejas/farmacología , Mezclas Complejas/uso terapéutico , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacosRESUMEN
This study examined the relationship between gingival crevicular fluid (GCF) and serum sclerostin and PGE2 levels and the inflammatory bone resorption associated with chronic apical periodontitis (AP) as well as the correlation between sclerostin regulation and RANKL and MMP-9 levels. Ninety participants were divided into three groups based on PAI scores, as follows: Group 1 (control group, PAI 1-2, n:35); Group 2 (PAI 3-4, n:35); Group 3 (PAI 5 in at least 1 tooth, n:55). Sclerostin, PGE2, RANKL, and MMP-9 levels were measured in the serum and GCF of all participants. GCF sclerostin, RANKL, and PGE2 levels of Group 3 were significantly higher than those of Groups 1 and 2 (75.8 ± 43.3, 37.0 ± 6.4 and 42.7 ± 8.2 ng/mL, p < 0.0001; 319 ± 167, 244 ± 41 and 248 ± 49 ng/L, p = 0.0029; 193 ± 87, 141 ± 90 and 137 ± 79 ng/L, p = 0.0028, respectively for Groups 3, 2, and 1). GCF MMP-9 levels of Group 3 were significantly higher than those of Group 1 (465 ± 162 and 384 ± 44 ng/mL, p = 0.0340). Group 3 also had elevated serum sclerostin and PGE-2 levels, but the differences between groups were less pronounced in serum than in GCF (p < 0.05). In the ROC analysis performed for the diagnostic performance of abscess formation in AP, the sensitivity of the GCF sclerostin and GCF PGE2 tests was determined as 65.5% and 72.7%, specificity as 98.6% and 68.6%, and AUC as 0.768 and 0.712, respectively (p < 0.0001). Both GCF sclerostin and PGE-2 independently showed close relationships with PAI-abscess scores used to determine AP severity and they can be used in combination for diagnosing and monitoring AP-related bone resorption.
Asunto(s)
Proteínas Morfogenéticas Óseas , Resorción Ósea , Periodontitis Periapical , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Periodontitis Periapical/metabolismo , Masculino , Femenino , Marcadores Genéticos , Ligando RANK/metabolismo , Ligando RANK/sangre , Adulto , Líquido del Surco Gingival/química , Persona de Mediana Edad , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/sangre , Dinoprostona/metabolismo , Dinoprostona/sangre , Proteínas Morfogenéticas Óseas/metabolismo , Proteínas Morfogenéticas Óseas/sangre , Resorción Ósea/metabolismo , Biomarcadores/metabolismoRESUMEN
Orthodontic tooth movement (OTM) involves the application of mechanical forces, leading to bone remodeling through a coordinated immune response. This process comprises four stages-initial, lag, acceleration, and retention-each characterized by specific immune mechanisms involving cytokines, immune cells, and signaling pathways. Inflammatory mediators, such as interleukin (IL)-1ß and tumor necrosis factor-alpha (TNF-α), initiate bone resorption, while regulatory cytokines like IL-10 promote tissue repair. The nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) balance regulates osteoclast activity, ensuring controlled bone remodeling. Understanding these immune responses provides valuable insights into optimizing orthodontic treatment outcomes by controlling inflammation and enhancing therapeutic efficiency. This knowledge is significant for alleviating pain during orthodontic treatment, reducing excessive resorption of periodontal tissues, and preventing post-treatment relapse.
Asunto(s)
Remodelación Ósea , Técnicas de Movimiento Dental , Humanos , Remodelación Ósea/inmunología , Técnicas de Movimiento Dental/efectos adversos , Animales , Citocinas/inmunología , Transducción de Señal , Osteoclastos/inmunología , Ligando RANK/inmunologíaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Shenqi Yanshen Granule (SYG), a traditional Chinese medicine formulation, is clinically used for chronic kidney disease-mineral bone and disorder (CKD-MBD) by tonifying the kidney, activating blood, eliminating toxins, and dispelling turbidity. However, its mechanism remains unclear. AIM OF THE STUDY: This study aimed to elucidate the therapeutic mechanism of SYG in CKD-MBD using an integrated approach combining proteomics and bioinformatics. MATERIALS AND METHODS: Forty-four CKD-MBD patients were divided into a treatment group (TG, n = 23) receiving standard therapy plus SYG (30g, twice daily), or a control group (CG, n = 21) receiving standard therapy alone. A normal group (NG, n = 20) served as healthy controls. After 8 weeks, renal function, mineral-bone metabolism parameters, and bone mineral density (BMD) were evaluated. Plasma proteomics was used to identify potential targets, followed by network pharmacology, molecular docking, and dynamics simulations to predict bioactive compounds. Finally, RANKL-stimulated RAW264.7 cells were conducted to validate the therapeutic targets and bioactive compounds. RESULTS: After 8 weeks of treatment in a small cohort, preliminary improvements were observed in renal function (Scr, BUN), mineral-bone metabolism markers (Ca, iPTH, 25(OH)VD, b-ALP, ß-CTX), and BMD in CKD-MBD patients. Plasma proteomics indicated that SYG downregulated PAK2 and CRKL within the MAPK pathway. Network pharmacology identified icariin as a constituent capable of binding both targets, which was supported by molecular docking and dynamics simulations showing stable complex formation under static and dynamic conditions. In vitro, both SYG and icariin significantly suppressed PAK2 and CRKL expression at mRNA and protein levels during RANKL-induced osteoclast differentiation in RAW264.7 cells. CONCLUSION: This study suggests that PAK2 and CRKL are potential therapeutic targets of SYG for ameliorating CKD-MBD, and icariin may be an important active ingredient. These findings provide a foundational mechanistic hypothesis that warrants further validation in larger-scale clinical trials.
Asunto(s)
Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica , Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Animales , Proteómica/métodos , Humanos , Masculino , Ratones , Femenino , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/tratamiento farmacológico , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/metabolismo , Persona de Mediana Edad , Células RAW 264.7 , Biología Computacional , Densidad Ósea/efectos de los fármacos , Simulación del Acoplamiento Molecular , Ligando RANK/metabolismo , Anciano , Farmacología en Red , AdultoRESUMEN
BACKGROUND: This study explores how varying dietary phosphorus levels, particularly through dicalcium phosphate (DCP) and tricalcium phosphate (TCP), influence egg production performance and bone quality in aging laying hens, along with tibia bone gene expression. A total of 576 laying hens were randomly assigned to a 2 × 4 factorial design (two phosphorus sources × four levels), with six replicates per treatment (12 hens each). Hens were housed under controlled environmental conditions. The study employed two-way analysis of variance to analyze 18 parameters related to production, egg quality, serum biochemistry, and bone traits, with post hoc Tukey tests for multiple comparisons. Egg and bone parameters were analyzed separately. Pearson's correlation assessed relationships while controlling for phosphorus level and hen age. RESULTS: Hens fed TCP had higher egg production and improved feed conversion ratio compared to DCP. Serum inorganic phosphorus was higher in DCP-fed hens. TCP also enhanced bone quality, with greater bone breaking strength, bone mineral density, and bone mineral content (BMC). Gene expression analysis revealed upregulated osteogenic markers (OPG and RANKL; P < 0.05) in TCP, while DCP elevated FGF23 expression (6.88). RANKL showed significant correlation with production traits: 43% with egg production (P < 0.001) and 32.1% with feed conversion (P < 0.01). These findings highlight that TCP supports bone health and calcium regulation, whereas DCP promotes bone resorption, ultimately reducing production longevity. CONCLUSION: TCP boosts productivity and bone health in aging hens by upregulating OPG/RANKL signaling, optimizing bone remodeling. Future studies should investigate long-term gene expression changes and alternative pathways. © 2025 Society of Chemical Industry.
Asunto(s)
Huesos , Pollos , Huevos , Fósforo Dietético , Fósforo , Animales , Pollos/genética , Pollos/metabolismo , Pollos/crecimiento & desarrollo , Pollos/fisiología , Femenino , Alimentación Animal/análisis , Fosfatos de Calcio/metabolismo , Factor-23 de Crecimiento de Fibroblastos , Huevos/análisis , Densidad Ósea , Fósforo/metabolismo , Fósforo Dietético/metabolismo , Fósforo Dietético/análisis , Huesos/metabolismo , Tibia/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Ligando RANK/metabolismo , Ligando RANK/genéticaRESUMEN
The regulation of bone mass relies on a dynamic interplay between boneforming osteoblasts and boneresorbing osteoclasts. Imbalances in this regulatory system favor bone resorption and are implicated in the development of osteolytic disorders such as osteoporosis. Although current treatments targeting osteoclast activity are effective, safety concerns remain a notable limitation. As a multifunctional adipokine, apelin (APLN) serves a role in angiogenesis and metabolic regulation. However, to the best of our knowledge, its involvement in osteoclast differentiation has not yet been characterized. The present study thus examined the effects of APLN on osteoclastogenesis using a murinemacrophage model stimulated with receptor activator of NFκB ligand (RANKL). The results revealed that APLN augmented RANKLinduced osteoclast differentiation, promoting the formation of tartrateresistant acid phosphatasepositive multinucleated cells and the development of organized Factin rings. Transcriptome analyses of a public dataset confirmed the temporal upregulation of osteoclastrelated genes under RANKL stimulation. It was further discovered that cotreatment with APLN and RANKL significantly enhanced the expression of these osteoclastspecific markers. APLN cotreatment with RANKL upregulated the ERK, JNK, p38 and NFκB signaling pathways, and this activation was effectively attenuated by specific pathway inhibitors. In conclusion, these findings identified APLN as an enhancer of RANKLdependent osteoclast differentiation and signaling, suggesting that the modulation of APLN activity may provide a promising strategy for controlling excessive bone resorption in skeletal diseases.
Asunto(s)
Apelina , Sistema de Señalización de MAP Quinasas , FN-kappa B , Osteoclastos , Osteogénesis , Ligando RANK , Animales , Ligando RANK/metabolismo , Ligando RANK/farmacología , Osteogénesis/efectos de los fármacos , Ratones , Apelina/farmacología , Apelina/metabolismo , FN-kappa B/metabolismo , Osteoclastos/metabolismo , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Células RAW 264.7 , Sistema de Señalización de MAP Quinasas/efectos de los fármacosRESUMEN
Excessive osteoclast-mediated bone resorption is central to osteoporosis pathogenesis. We initially observed that Acyl-CoA Cholesterol Acyltransferase-1 (ACAT1) is significantly upregulated during receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastogenesis, and its knockdown potently inhibited osteoclastogenesis. This prompted us to investigate the therapeutic potential of Avasimibe (AVA), a specific ACAT1 inhibitor, originally developed for atherosclerosis due to its suppression of cholesterol esterification and anti-inflammatory effects, for osteoporosis treatment. In vitro, AVA markedly suppressed RANKL-induced osteoclastogenesis without cytotoxicity, as demonstrated by tartrate-resistant acid phosphatase (TRAP) staining, immunofluorescence, quantitative real-time PCR (qRT-PCR), and western blot analysis. In vivo, AVA administration effectively attenuated bone loss in ovariectomized (OVX) mice, significantly improving bone mineral density, preserving trabecular microarchitecture. Mechanistically, RNA sequencing (RNA-seq) and bioinformatic analysis revealed that AVA downregulates creatine kinase B (CKB), a key mediator identified as upregulated during osteoclastogenesis, consequently inhibiting the phosphatidylinositol 3-kinase-protein kinase B (PI3K-AKT) signaling pathway. Critically, the inhibitory effects of AVA on osteoclast differentiation and PI3K-AKT activation were reversed by exogenous phosphocreatine (PCr). Collectively, our data demonstrate that AVA attenuates osteoclastogenesis and bone resorption by targeting the CKB/PI3K-AKT axis, identifying it as a promising novel therapeutic candidate for osteoporosis.
Asunto(s)
Acetil-CoA C-Acetiltransferasa , Resorción Ósea , Osteoclastos , Osteoporosis , Esterol O-Aciltransferasa , Animales , Ovariectomía , Femenino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones , Osteogénesis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Osteoclastos/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Ratones Endogámicos C57BL , Osteoporosis/tratamiento farmacológico , Acetil-CoA C-Acetiltransferasa/antagonistas & inhibidores , Acetil-CoA C-Acetiltransferasa/metabolismo , Humanos , Resorción Ósea/tratamiento farmacológico , Esterol O-Aciltransferasa/antagonistas & inhibidores , Esterol O-Aciltransferasa/metabolismo , Ligando RANK/metabolismo , Células RAW 264.7RESUMEN
As a frequent complication of diabetes, diabetic osteoporosis (DOP) represents a growing clinical and public health challenge. The increased osteoclastogenesis in diabetic pathological states results in bone resorption and bone loss and the exacerbation of osteoporosis. Cryptotanshinone, a fat-soluble diterpenoid anthraquinone compound extracted from Salvia. miltiorrhiza Bge, has been demonstrated efficacy in the treatment of a variety of diseases. In this study, we present evidence that cryptotanshinone inhibits RANKL-induced osteoclast differentiation in a concentration-dependent manner in vitro. Furthermore, cryptotanshinone suppresses diabetic osteoporosis by inhibiting osteoclastogenesis in vivo. Mechanistically, cryptotanshinone binds to lymphocyte cytosolic protein 1 (LCP1) so that suppressing osteoclast fusion to reduce bone resorption. Collectively, these findings suggest that cryptotanshinone suppresses osteoclast differentiation and bone loss of DOP by targeting LCP1. Consequently, cryptotanshinone may represent a promising therapeutic agent for diabetic osteoporosis.
Asunto(s)
Complicaciones de la Diabetes , Diabetes Mellitus Experimental , Osteoclastos , Osteoporosis , Fenantrenos , Animales , Fenantrenos/uso terapéutico , Fenantrenos/farmacología , Osteoclastos/efectos de los fármacos , Osteoclastos/fisiología , Diferenciación Celular/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Osteoporosis/etiología , Ratones , Humanos , Ratones Endogámicos C57BL , Osteogénesis/efectos de los fármacos , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Masculino , Ligando RANK/metabolismo , Células RAW 264.7 , Complicaciones de la Diabetes/tratamiento farmacológico , Salvia miltiorrhiza/inmunologíaRESUMEN
BACKGROUND: The objective of our study was to examine the role of Chemerin, Chemokine like receptor 1 (CMKLR1), receptor activator of nuclear factor kappa-Β ligand (RANKL), and Osteoprotegerin (OPG) in the development of bone-invasive oral squamous cell carcinoma. METHODS: In order to evaluate the presence of these markers at the interface between bone and tumor, immunohistochemical analyses were conducted using tissue microarrays obtained from 164 patients with oral squamous cell carcinoma growing in close contact with jaw bone. RESULTS: The findings indicate that Chemerin and Osteoprotegerin are notably reduced in tumors that have invaded the bone. Only 21 (32.8%) of pT4a tumors (defined as bone invasive) had a high Osteoprotegerin expression, whereas 36 (66.7%) of pT2 and pT3 tumors demonstrated high expression of Osteoprotegerin (p < 0.001). Similarly, we saw a downregulation of Chemerin in 50 (60.2%) bone invasive oral squamous cell carcinoma samples compared to 28 (35.0%) in non-bone invasive tumors (p = 0.002). In addition, our data indicated a connection between worst pattern of invasion score and less favorable overall and disease-specific survival (p = 0.007 and p = 0.024, respectively). CONCLUSIONS: The findings suggest that Chemerin and Osteoprotegerin have the potential to serve as indicators for bone invasion in oral squamous cell carcinoma, which could have significant implications for diagnosis and treatment approaches.
Asunto(s)
Biomarcadores de Tumor , Neoplasias Óseas , Carcinoma de Células Escamosas , Quimiocinas , Péptidos y Proteínas de Señalización Intercelular , Neoplasias de la Boca , Osteoprotegerina , Humanos , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Osteoprotegerina/análisis , Osteoprotegerina/metabolismo , Quimiocinas/análisis , Quimiocinas/metabolismo , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/metabolismo , Pronóstico , Masculino , Femenino , Invasividad Neoplásica , Persona de Mediana Edad , Anciano , Ligando RANK/análisis , Ligando RANK/metabolismo , Adulto , Receptores de Quimiocina , Neoplasias Óseas/secundario , Anciano de 80 o más AñosRESUMEN
OBJECTIVE: To test whether systemic green or red propolis modulates inflammation and bone resorption in rat apical periodontitis (AP). DESIGN: Twenty-four male Wistar rats received AP induction in the first mandibular molars and were randomized to Control, Green propolis, or Red propolis (nâ¯=â¯8/group). Propolis (100â¯mg/kg in water) or vehicle was administered daily by gavage for 30 days. On day 30, periapical tissues were evaluated by micro-CT, histology (inflammatory score), and immunohistochemistry for RANKL, OPG, and TRAP-positive osteoclasts. Data were analyzed with Shapiro-Wilk, Kruskal-Wallis/Dunn, or one-way ANOVA/Tukey (α=0.05). RESULTS: Both propolis groups showed significantly less periapical bone resorption than the control group on micro-CT analysis (pâ¯<â¯0.05). Histological evaluation revealed predominantly chronic inflammatory infiltrates, with significantly lower inflammation scores in the propolis-treated groups (pâ¯<â¯0.05). Immunohistochemical analysis demonstrated a significant reduction in RANKL expression, an increase in OPG levels, and fewer TRAP-positive multinucleated cells in both propolis groups compared to the control (pâ¯<â¯0.05). No significant differences were observed between green and red propolis. CONCLUSION: Thirty days of systemic green or red propolis similarly attenuated periapical inflammation and osteoclast-mediated bone resorption in experimental AP, reflected by lower resorption volumes, reduced RANKL/TRAP, and higher OPG, indicating that propolis may serve as a host-modulatory adjunct to preserve periapical bone.
Asunto(s)
Pérdida de Hueso Alveolar , Resorción Ósea , Inflamación , Periodontitis Periapical , Própolis , Animales , Própolis/farmacología , Própolis/uso terapéutico , Própolis/administración & dosificación , Ratas Wistar , Masculino , Periodontitis Periapical/tratamiento farmacológico , Periodontitis Periapical/patología , Periodontitis Periapical/diagnóstico por imagen , Ratas , Ligando RANK/metabolismo , Microtomografía por Rayos X , Pérdida de Hueso Alveolar/prevención & control , Pérdida de Hueso Alveolar/diagnóstico por imagen , Resorción Ósea/prevención & control , Osteoclastos/efectos de los fármacos , Osteoprotegerina/metabolismo , Inmunohistoquímica , Modelos Animales de Enfermedad , Distribución AleatoriaRESUMEN
PURPOSE: Mouse models demonstrate a role for RANK and its ligand, RANKL, in osteosarcoma. The primary objective of this single-arm, open-label phase 2 trial was to determine whether denosumab, a RANKL mAb, improved disease control in recurrent osteosarcoma relative to benchmarks derived from historic Children's Oncology Group clinical trial data. PATIENTS AND METHODS: Skeletally mature patients ages 11 to 49 years old with measurable disease were eligible for cohort 1, and those with complete surgical resection of all sites of disease were eligible for cohort 2. Patients received denosumab 120 mg subcutaneously every 4 weeks with calcium and vitamin D supplementation. The primary endpoints were RECIST response and remaining event-free for 4 months for cohort 1 and remaining event-free for 12 months for cohort 2. Toxicity, pharmacokinetics, and pharmacodynamic effects were additional endpoints. RESULTS: Fifteen patients in cohort 1 and 38 in cohort 2 were eligible and evaluable for the primary endpoint. One of 15 cohort 1 patients remained event-free at 4 months. There were no objective responses. Ten of 38 cohort 2 patients were event-free at 12 months. The predefined efficacy criteria were not met in either cohort. The most common ≥ grade 3 adverse events were hypocalcemia and hypophosphatemia (8% and 11%, respectively). At steady state, mean serum denosumab trough concentrations were 23.7 to 31 µg/mL in cycles 2 to 7. Serum c-telopeptide and urine n-telopeptide decreased on treatment. CONCLUSIONS: Denosumab was well-tolerated with anticipated side effects and pharmacokinetic and pharmacodynamic parameters but had insufficient activity for further development in osteosarcoma.
Asunto(s)
Neoplasias Óseas , Denosumab , Recurrencia Local de Neoplasia , Osteosarcoma , Ligando RANK , Humanos , Denosumab/administración & dosificación , Denosumab/efectos adversos , Denosumab/uso terapéutico , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Osteosarcoma/mortalidad , Niño , Adolescente , Femenino , Masculino , Adulto , Adulto Joven , Ligando RANK/antagonistas & inhibidores , Ligando RANK/inmunología , Persona de Mediana Edad , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Resistencia a Antineoplásicos , Resultado del TratamientoRESUMEN
Previous research has established that memory B cells contribute to osteoclastogenesis by producing RANKL. However, the phenotypic and functional alterations of switched (CD27 + IgD-) and unswitched (CD27 + IgD +) memory B cells during periodontitis were not fully understood. This study aims to elucidate the specific role of unswitched memory B cells in periodontitis. We analyzed the distribution and function of both memory B cell subsets using flow cytometry to assess their frequency and phenotype. The production of cytokines RANKL, TNF-α, and IL-6 was evaluated using ELISA and PCR. Additionally, cell culture experiments were performed to investigate the impact of TLRs on cytokine production by memory B cells and their capacity to induce osteoclastogenesis. Our findings revealed a higher proportion of switched memory B cells and a lower proportion of unswitched memory B cells in the gingival tissues of periodontitis patients compared to healthy individuals (p < 0.05). Periodontal inflammation was associated with increased TNF-α mRNA levels in switched memory B cells and elevated IL-6 mRNA levels in unswitched memory B cells, with TLR9 and TLR7/8 playing roles in these processes. Furthermore, TLR4 enhanced the ability of memory B cells to produce RANKL and promote osteoclastogenesis. These results suggest a novel mechanism by which unswitched memory B cells contribute to periodontal inflammation and alveolar bone resorption, independent of antibody secretion, and highlight the potential role of TLRs in exacerbating local inflammation during periodontitis.
Asunto(s)
Linfocitos B , Citocinas , Células B de Memoria , Periodontitis , Receptores Toll-Like , Humanos , Periodontitis/inmunología , Periodontitis/metabolismo , Receptores Toll-Like/metabolismo , Masculino , Interleucina-6/metabolismo , Femenino , Adulto , Factor de Necrosis Tumoral alfa/metabolismo , Ligando RANK/metabolismo , Citocinas/metabolismo , Citometría de Flujo , Persona de Mediana Edad , Células B de Memoria/metabolismo , Células B de Memoria/inmunología , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
Although plastic products have offered substantial benefits to modern society and daily life, their degradation into microplastics (MPs) has raised significant concerns owing to their adverse effects on ecosystems and human health. This study investigated MP deposition in human skeletal tissues and elucidated their effects on bone metabolism. Comprehensive analysis of human bone tissue using Nile red staining, Raman spectroscopy, and infrared microspectroscopy identified MP particles in 33 out of 40 samples (covering the cervical, thoracic, and lumbar vertebrae, as well as the upper and lower limb bones). These detected MPs exhibited a granular morphology, with particle sizes ranging from 10 to 20 µm, predominantly composed of polyethylene and polypropylene, with 2-3 MPs/2â¯g bone tissues in each sample. To explore the underlying mechanisms, transcriptomic profiling of femoral tissues from MP-PE-fed mice revealed 870 up-regulated and 930 down-regulated genes, which were enriched in the hematopoietic cell lineage, NF-κB, PPAR, PI3K-Akt, and HIF-1 signaling pathways, and metabolic pathways. In vitro validation further demonstrated that MPs enhanced osteoclast differentiation by modulating the RANKL/OPG axis in bone marrow stromal cells, thereby activating the RANK-NFATc1 signaling pathway in Raw264.7 cells. These findings provide experimental and theoretical evidence of the detrimental impact of MPs on skeletal health, underscoring the urgent need for environmental and public health interventions.
Asunto(s)
Resorción Ósea , Microplásticos , Osteoprotegerina , Ligando RANK , Transcriptoma , Animales , Humanos , Ratones , Ligando RANK/metabolismo , Ligando RANK/genética , Microplásticos/toxicidad , Transcriptoma/efectos de los fármacos , Células RAW 264.7 , Osteoprotegerina/metabolismo , Osteoprotegerina/genética , Masculino , Transducción de Señal/efectos de los fármacos , Femenino , Ratones Endogámicos C57BL , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Perfilación de la Expresión Génica , Huesos/metabolismo , Huesos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Resorción Ósea/inducido químicamente , Resorción Ósea/metabolismo , Resorción Ósea/genéticaRESUMEN
OBJECTIVE: This study aimed to investigate the effects of resistance exercise on the progression of periodontal disease in rats, focusing on alveolar bone loss, attachment loss, and local inflammatory and bone metabolic markers. MATERIALS AND METHODS: Forty male Wistar albino rats were allocated into four experimental groups in a 2â¯×â¯2 factorial design: G1 or G2 and G3 or G4. The exercise protocol consisted of progressive swimming sessions over eight weeks, with resistance provided by weights tied to the animals. In the final week, MBT was performed, and rats were sacrificed for histomorphometric and immunohistochemical analysis. RESULTS: The values for alveolar bone loss and attachment loss were significantly lower in the exercised groups compared to both the G1 and G2 groups (pâ¯<â¯0.001). Among the rats with periodontitis, TNF-α expression was significantly lower in the exercised group (pâ¯=â¯0.002), whereas IL-10 levels showed no significant differences (pâ¯>â¯0.005). RANKL expression was elevated in G2 (pâ¯=â¯0.039), with no significant variation in OPG among groups. In MBT, G2 showed significantly higher values compared to G1 and G3 (pâ¯=â¯0.004). G4 displayed intermediate values, higher than G3 but lower than G2, without statistical significance (pâ¯>â¯0.005). CONCLUSION: Physical exercise reduced TNF-α levels in the presence of periodontitis and increased IL-10, although the latter change was not statistically significant. Exercise also contributed to a decrease in RANKL/OPG expression, suggesting a protective effect on alveolar bone resorption. MBT findings further indicate that exercise may alleviate periodontitis-associated behavioral alterations, supporting its potential role as an adjunctive therapy in managing periodontitis.
Asunto(s)
Pérdida de Hueso Alveolar , Artritis Reumatoide , Inflamación , Pérdida de la Inserción Periodontal , Periodontitis , Condicionamiento Físico Animal , Animales , Ratas Wistar , Masculino , Periodontitis/patología , Periodontitis/metabolismo , Periodontitis/terapia , Pérdida de Hueso Alveolar/patología , Pérdida de Hueso Alveolar/metabolismo , Ratas , Factor de Necrosis Tumoral alfa/metabolismo , Condicionamiento Físico Animal/fisiología , Inmunohistoquímica , Ligando RANK/metabolismo , Osteoprotegerina/metabolismo , Interleucina-10/metabolismo , Modelos Animales de Enfermedad , Artritis Reumatoide/patología , Artritis Reumatoide/metabolismo , Pérdida de la Inserción Periodontal/patologíaRESUMEN
Postmenopausal osteoporosis is a prevalent bone disorder characterized by an imbalance in bone homeostasis following estrogen decline, which leads to progressive bone loss. Research has shown that estrogen deprivation-induced osteoporosis (OVX) is partly dependent on the gut microbiota and its metabolites, a process that can be therapeutically targeted through supplementation with probiotics or the metabolites themselves. Multiple studies have revealed the multifaceted roles of indole and its derivatives in bone health and the pathophysiology of skeletal disorders. These compounds are exclusively synthesized from tryptophan by the gut microbiota. However, the underlying mechanisms and relationships of gut microbiota-derived indole and its derivatives in osteoporosis remain unclear. Our study aimed to explore the influence and mechanism of gut microbiota-derived indole and its derivatives on the development of osteoporosis. In this study, we confirmed that the gut microbiota was altered in OVX mouse model, which was manifested as decreased Lactobacillus genus in the gut and reduced levels of the related indoleacetic acid (IAA) in serum. IAA was significantly positively correlated with bone mass and the abundance of Lactobacillus genus. Specifically, IAA inhibited RANKL-induced PI3K-AKT signaling activation and ROS production, reduced NFATc1 nuclear translocation in BMMs, eventually suppressed osteoclast formation and bone resorption function. The agonist SC-79 restored the IAA-inhibited osteoclast formation. In vivo, daily IAA supplementation conferred protection from OVX-induced bone loss by significantly attenuating osteoclast resorption and enhancing Nrf2 expression. Overall, we elucidated the mechanisms of osteoclastogenesis during osteoporosis to facilitate the development of a new therapy using gut microbial metabolite IAA in addition to the existing therapeutics.
Asunto(s)
Microbioma Gastrointestinal , Factores de Transcripción NFATC , Osteoporosis Posmenopáusica , Osteoporosis , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción NFATC/metabolismo , Factores de Transcripción NFATC/genética , Transducción de Señal , Femenino , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/patología , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/microbiología , Osteoporosis Posmenopáusica/patología , Osteoporosis/metabolismo , Osteoporosis/patología , Osteoporosis/microbiología , Ligando RANK/metabolismo , Ligando RANK/genética , Humanos , Osteogénesis , Ratones Endogámicos C57BL , Lactobacillus/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Modelos Animales de Enfermedad , Ovariectomía , Indoles/metabolismo , Ácidos IndolacéticosRESUMEN
Osteoclast functioning determines homeostasis of bone texture, healing speed after bone injury, and integrity after bone remodeling. Osteoclastogenesis is tightly controlled by transcriptional factors and cytokine-mediated signaling. The activating transcription factor 4 (Atf4) and interleukin 6 (IL6) have been considered to be involved in osteoclastogenesis, but their interaction on osteoclast differentiation is still largely unclear. Here we aimed to investigate their interaction on osteoclast differentiation and activity. Through lentiviral overexpression and siRNA transfection, we showed that Atf4 regulated osteoclastogenesis by upregulating the expression of osteoclast markers, including Nfatc1, c-Fos, Dcst1, Mmp2 and 9, and cathepsin K. Atf4-mediated osteoclastogenesis was largely dependent on activation of IL6 signaling through the direct binding of Atf4 to the IL6 promoter by ChIP assay. Atf4-IL6 axis activated the Jak1/Stat3 signaling to promote the formation of large, multinucleated osteoclasts. Taken together, these results indicate the important interaction between Atf4 and IL6 signaling on osteoclast differentiation beyond canonical MCSF and RANKL signaling and emphasize the multi-regulatory mechanism of Atf4-mediated osteoclastogenesis, which provides us with understanding of osteoporotic diseases and cues for therapeutic strategies.
Asunto(s)
Factor de Transcripción Activador 4 , Diferenciación Celular , Interleucina-6 , Osteoclastos , Osteogénesis , Osteoclastos/metabolismo , Osteoclastos/citología , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Animales , Diferenciación Celular/fisiología , Ratones , Interleucina-6/metabolismo , Interleucina-6/genética , Transducción de Señal/fisiología , Osteogénesis/fisiología , Ratones Endogámicos C57BL , Factores de Transcripción NFATC/metabolismo , Células RAW 264.7 , Factor de Transcripción STAT3/metabolismo , Ligando RANK/metabolismo , Células CultivadasRESUMEN
Osteoporosis is a systemic skeletal disease that severely impairs the health of the elderly population. The interaction between the receptor activator of the NF-κB ligand (RANKL) and its receptor RANK is critical for osteoclast differentiation and function. Therefore, targeting the RANKL/RANK interaction represents a promising strategy for osteoporosis. In this study, we employed a newly established yeast two-hybrid system based on RANKL/RANK interaction and identified IMB-R38, a novel benzamide compound that dose-dependently blocked RANKL/RANK interaction by inhibiting the growth of AH109 cells harboring pAD-RANKL/pBD-RANK plasmids in quadruple-dropout medium. IMB-R38 significantly suppressed osteoclast differentiation, disrupted F-actin ring formation, and downregulated the expression of osteoclast-specific genes, including NFATc1 and MMP9 in RANKL-induced RAW264.7 macrophages. IMB-R38 also promoted osteoblast differentiation by upregulating the expression of osteogenic genes. Importantly, in a dexamethasone (DXM)-induced osteoporotic zebrafish model, IMB-R38 significantly increased bone mineralization, with anti-osteoporosis efficacy superior to that of alendronate sodium (Alen). RT-qPCR assays showed that IMB-R38 significantly upregulated the mRNA expression of osteogenesis genes (Bmp2, Runx2a, Runx2b, Sp7, Alp, and Oc) while markedly downregulating that of the osteoclastogenesis genes (Mmp9, Mmp13, and Mmp2) compared with the DXM group. Mechanistically, an SPR assay confirmed that IMB-R38 directly binds with RANK but not RANKL to disrupt RANKL/RANK interaction. Furthermore, Asp168 of RANK was identified as a key amino acid that mediates both RANKL interaction and IMB-R38 binding. The inhibition of RANKL/RANK by IMB-R38 suppressed JNK phosphorylation and, consequently, osteoclast differentiation and function. Collectively, our findings identify IMB-R38 as a novel RANKL/RANK inhibitor with therapeutic potential for osteoporosis through its regulation of bone metabolism.