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1.
Nat Commun ; 12(1): 5196, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465793

RESUMO

Bone metastasis is an incurable complication of breast cancer. In advanced stages, patients with estrogen-positive tumors experience a significantly higher incidence of bone metastasis (>87%) compared to estrogen-negative patients (<56%). To understand the mechanism of this bone-tropism of ER+ tumor, and to identify liquid biopsy biomarkers for patients with high risk of bone metastasis, the secreted extracellular vesicles and cytokines from bone-tropic breast cancer cells are examined in this study. Both exosomal miR-19a and Integrin-Binding Sialoprotein (IBSP) are found to be significantly upregulated and secreted from bone-tropic ER+ breast cancer cells, increasing their levels in the circulation of patients. IBSP is found to attract osteoclast cells and create an osteoclast-enriched environment in the bone, assisting the delivery of exosomal miR-19a to osteoclast to induce osteoclastogenesis. Our findings reveal a mechanism by which ER+ breast cancer cells create a microenvironment favorable for colonization in the bone. These two secreted factors can also serve as effective biomarkers for ER+ breast cancer to predict their risks of bone metastasis. Furthermore, our screening of a natural compound library identifies chlorogenic acid as a potent inhibitor for IBSP-receptor binding to suppress bone metastasis of ER+ tumor, suggesting its preventive use for bone recurrence in ER+ patients.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias da Mama/metabolismo , Exossomos/metabolismo , Sialoproteína de Ligação à Integrina/metabolismo , MicroRNAs/metabolismo , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Exossomos/genética , Feminino , Humanos , Sialoproteína de Ligação à Integrina/genética , Camundongos , Camundongos Knockout , Camundongos Nus , MicroRNAs/genética , Metástase Neoplásica , Osteoclastos/metabolismo , Receptores de Estrogênio/metabolismo
2.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502045

RESUMO

Bone is a highly dynamic tissue that is constantly adapting to micro-changes to facilitate movement. When the balance between bone building and resorption shifts more towards bone resorption, the result is reduced bone density and mineralization, as seen in osteoporosis or osteopenia. Current treatment strategies aimed to improve bone homeostasis and turnover are lacking in efficacy, resulting in the search for new preventative and nutraceutical treatment options. The myokine irisin, since its discovery in 2012, has been shown to play an important role in many tissues including muscle, adipose, and bone. Evidence indicate that irisin is associated with increased bone formation and decreased bone resorption, leading to reduced risk of osteoporosis in post-menopausal women. In addition, low serum irisin levels have been found in individuals with osteoporosis and osteopenia. Irisin targets key signaling proteins, promoting osteoblastogenesis and reducing osteoclastogenesis. The present review summarizes the existing evidence regarding the effects of irisin on bone homeostasis.


Assuntos
Fibronectinas/metabolismo , Homeostase , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Animais , Humanos
3.
Biomed Res Int ; 2021: 5565973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34485516

RESUMO

Osteoclast, which mediates overactive bone resorption, is one of the key factors for bone destruction in rheumatoid arthritis (RA). Existing studies have shown that abnormal miR-143-3p expression was observed in both RA patients and arthritis animals, which can participate in osteoclast differentiation, and mitogen-activated protein kinase (MAPK) signaling pathway was closely related to osteoclast differentiation. The primary objective of the current study was to determine the role of miR-143-3p in the progression of osteoclast differentiation and its relationship with MAPK signaling pathways. The results showed that miR-143-3p inhibited osteoclast differentiation and decreased the levels of M-CSF and RANKL during osteoclast differentiation. miR-143-3p inhibited the expression of MAPK signaling proteins, which is ERK1/2 in the early stage and JNK in the later stage of osteoclast differentiation. It was also observed that MAPK inhibitors upregulated miR-143-3p expression in osteoclast differentiation. Taken together, our results suggested that miR-143-3p could inhibit the differentiation of osteoclast, which was related to inhibiting MAPK signaling pathways. This may provide a novel strategy for curing RA.


Assuntos
Artrite Reumatoide/metabolismo , Fibroblastos/citologia , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Monócitos/citologia , Osteoclastos/citologia , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Monócitos/metabolismo , Osteoclastos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
4.
Int J Mol Sci ; 22(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34576310

RESUMO

Hypoxia is evident in several bone diseases which are characterized by excessive bone resorption by osteoclasts, the bone-resorbing cells. The effects of hypoxia on osteoclast formation and activities are widely studied but remain inconclusive. This systematic review discusses the studies reporting the effect of hypoxia on osteoclast differentiation and activity. A literature search for relevant studies was conducted through SCOPUS and PUBMED MEDLINE search engines. The inclusion criteria were original research articles presenting data demonstrating the effect of hypoxia or low oxygen on osteoclast formation and activity. A total of 286 studies were identified from the search, whereby 20 studies were included in this review, consisting of four in vivo studies and 16 in vitro studies. In total, 12 out of 14 studies reporting the effect of hypoxia on osteoclast activity indicated higher bone resorption under hypoxic conditions, 14 studies reported that hypoxia resulted in more osteoclasts, one study found that the number remained unchanged, and five studies indicated that the number decreased. In summary, examination of the relevant literature suggests differences in findings between studies, hence the impact of hypoxia on osteoclasts remains debatable, even though there is more evidence to suggest it promotes osteoclast differentiation and activity.


Assuntos
Reabsorção Óssea/metabolismo , Hipóxia/metabolismo , Osteoclastos/metabolismo , Animais , Reabsorção Óssea/etiologia , Humanos , Hipóxia/complicações , Osteoclastos/citologia , Osteoclastos/patologia , Osteogênese
5.
Nutrients ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34444982

RESUMO

Several natural compounds, such as vitamin K2, have been highlighted for their positive effects on bone metabolism. It has been proposed that skeletal disorders, such as osteoporosis, may benefit from vitamin K2-based therapies or its regular intake. However, further studies are needed to better clarify the effects of vitamin K2 in bone disorders. To this aim, we developed in vitro a three-dimensional (3D) cell culture system one step closer to the bone microenvironment based on co-culturing osteoblasts and osteoclasts precursors obtained from bone specimens and peripheral blood of the same osteoporotic patient, respectively. Such a 3-D co-culture system was more informative than the traditional 2-D cell cultures when responsiveness to vitamin K2 was analyzed, paving the way for data interpretation on single patients. Following this approach, the anabolic effects of vitamin K2 on the osteoblast counterpart were found to be correlated with bone turnover markers measured in osteoporotic patients' sera. Overall, our data suggest that co-cultured osteoblasts and osteoclast precursors from the same osteoporotic patient may be suitable to generate an in vitro 3-D experimental model that potentially reflects the individual's bone metabolism and may be useful to predict personal responsiveness to nutraceutical or drug molecules designed to positively affect bone health.


Assuntos
Osso e Ossos/efeitos dos fármacos , Nutrientes/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteoporose , Medicina de Precisão/métodos , Vitamina K 2/farmacologia , Biomarcadores/sangue , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Células Cultivadas , Técnicas de Cocultura/métodos , Feminino , Humanos , Masculino , Modelos Biológicos , Nutrientes/uso terapêutico , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Modelagem Computacional Específica para o Paciente , Vitamina K 2/uso terapêutico , Vitaminas/farmacologia , Vitaminas/uso terapêutico
6.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445596

RESUMO

O-linked-N-acetylglucosaminylation (O-GlcNAcylation) performed by O-GlcNAc transferase (OGT) is a nutrient-responsive post-translational modification (PTM) via the hexosamine biosynthetic pathway (HBP). Various transcription factors (TFs) are O-GlcNAcylated, affecting their activities and significantly contributing to cellular processes ranging from survival to cellular differentiation. Given the pleiotropic functions of O-GlcNAc modification, it has been studied in various fields; however, the role of O-GlcNAcylation during osteoclast differentiation remains to be explored. Kinetic transcriptome analysis during receptor activator of nuclear factor-kappaB (NF-κB) ligand (RANKL)-mediated osteoclast differentiation revealed that the nexus of major nutrient metabolism, HBP was critical for this process. We observed that the critical genes related to HBP activation, including Nagk, Gfpt1, and Ogt, were upregulated, while the global O-GlcNAcylation was increased concomitantly during osteoclast differentiation. The O-GlcNAcylation inhibition by the small-molecule inhibitor OSMI-1 reduced osteoclast differentiation in vitro and in vivo by disrupting the translocation of NF-κB p65 and nuclear factor of activated T cells c1 (NFATc1) into the nucleus by controlling their PTM O-GlcNAcylation. Furthermore, OSMI-1 had a synergistic effect with bone target therapy on osteoclastogenesis. Lastly, knocking down Ogt with shRNA (shOgt) mimicked OSMI-1's effect on osteoclastogenesis. Targeting O-GlcNAcylation during osteoclast differentiation may be a valuable therapeutic approach for osteoclast-activated bone diseases.


Assuntos
Vias Biossintéticas , Diferenciação Celular , Hexosaminas/metabolismo , Osteoclastos/citologia , Processamento de Proteína Pós-Traducional , Ligante RANK/metabolismo , Acilação , Animais , Proliferação de Células , Glicosilação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , N-Acetilglucosaminiltransferases/metabolismo , Osteoclastos/metabolismo , Transdução de Sinais
7.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360988

RESUMO

Replacement and inflammatory resorption are serious complications associated with the delayed replantation of avulsed teeth. In this study, we aimed to assess whether deferoxamine (DFO) can suppress inflammation and osteoclastogenesis in vitro and attenuate inflammation and bone resorption in a replanted rat tooth model. Cell viability and inflammation were evaluated in RAW264.7 cells. Osteoclastogenesis was confirmed by tartrate-resistant acid phosphatase staining, reactive oxygen species (ROS) measurement, and quantitative reverse transcriptase-polymerase chain reaction in teeth exposed to different concentrations of DFO. In vivo, molars of 31 six-week-old male Sprague-Dawley rats were extracted and stored in saline (n = 10) or DFO solution (n = 21) before replantation. Micro-computed tomography (micro-CT) imaging and histological analysis were performed to evaluate inflammation and root and alveolar bone resorption. DFO downregulated the genes related to inflammation and osteoclastogenesis. DFO also reduced ROS production and regulated specific pathways. Furthermore, the results of the micro-CT and histological analyses provided evidence of the decrease in inflammation and hard tissue resorption in the DFO group. Overall, these results suggest that DFO reduces inflammation and osteoclastogenesis in a tooth replantation model, and thus, it has to be further investigated as a root surface treatment option for an avulsed tooth.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Desferroxamina/uso terapêutico , Osteogênese , Avulsão Dentária/tratamento farmacológico , Perda do Osso Alveolar/etiologia , Animais , Anti-Inflamatórios/farmacologia , Regeneração Óssea , Desferroxamina/farmacologia , Masculino , Camundongos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Avulsão Dentária/complicações
8.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360948

RESUMO

Osteoporosis is one of the major bone disorders that affects both women and men, and causes bone deterioration and bone strength. Bone remodeling maintains bone mass and mineral homeostasis through the balanced action of osteoblasts and osteoclasts, which are responsible for bone formation and bone resorption, respectively. The imbalance in bone remodeling is known to be the main cause of osteoporosis. The imbalance can be the result of the action of various molecules produced by one bone cell that acts on other bone cells and influence cell activity. The understanding of the effect of these molecules on bone can help identify new targets and therapeutics to prevent and treat bone disorders. In this article, we have focused on molecules that are produced by osteoblasts, osteocytes, and osteoclasts and their mechanism of action on these cells. We have also summarized the different pharmacological osteoporosis treatments that target different molecular aspects of these bone cells to minimize osteoporosis.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Hormônios e Agentes Reguladores de Cálcio/farmacologia , Osteoporose/metabolismo , Animais , Conservadores da Densidade Óssea/uso terapêutico , Remodelação Óssea , Hormônios e Agentes Reguladores de Cálcio/uso terapêutico , Humanos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/patologia
9.
Theranostics ; 11(16): 7735-7754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335961

RESUMO

Rationale: Multiple myeloma (MM) is a multifocal malignancy of bone marrow plasma cells, characterized by vicious cycles of remission and relapse that eventually culminate in death. The disease remains mostly incurable largely due to the complex interactions between the bone microenvironment (BME) and MM cells (MMC). In the "vicious cycle" of bone disease, abnormal activation of osteoclasts (OCs) by MMC causes severe osteolysis, promotes immune evasion, and stimulates the growth of MMC. Disrupting these cancer-stroma interactions would enhance treatment response. Methods: To disrupt this cycle, we orthogonally targeted nanomicelles (NM) loaded with non-therapeutic doses of a photosensitizer, titanocene (TC), to VLA-4 (α4ß1, CD49d/CD29) expressing MMC (MM1.S) and αvß3 (CD51/CD61) expressing OC. Concurrently, a non-lethal dose of a radiopharmaceutical, 18F-fluorodeoxyglucose ([18F]FDG) administered systemically interacted with TC (radionuclide stimulated therapy, RaST) to generate cytotoxic reactive oxygen species (ROS). The in vitro and in vivo effects of RaST were characterized in MM1.S cell line, as well as in xenograft and isograft MM animal models. Results: Our data revealed that RaST induced non-enzymatic hydroperoxidation of cellular lipids culminating in mitochondrial dysfunction, DNA fragmentation, and caspase-dependent apoptosis of MMC using VLA-4 avid TC-NMs. RaST upregulated the expression of BAX, Bcl-2, and p53, highlighting the induction of apoptosis via the BAK-independent pathway. The enhancement of multicopper oxidase enzyme F5 expression, which inhibits lipid hydroperoxidation and Fenton reaction, was not sufficient to overcome RaST-induced increase in the accumulation of irreversible function-perturbing α,ß-aldehydes that exerted significant and long-lasting damage to both DNA and proteins. In vivo, either VLA-4-TC-NM or αvß3-TC-NMs RaST induced a significant therapeutic effect on immunocompromised but not immunocompetent MM-bearing mouse models. Combined treatment with both VLA-4-TC-NM and αvß3-TC-NMs synergistically inhibited osteolysis, reduced tumor burden, and prevented rapid relapse in both in vivo models of MM. Conclusions: By targeting MM and bone cells simultaneously, combination RaST suppressed MM disease progression through a multi-prong action on the vicious cycle of bone cancer. Instead of using the standard multidrug approach, our work reveals a unique photophysical treatment paradigm that uses nontoxic doses of a single light-sensitive drug directed orthogonally to cancer and bone cells, followed by radionuclide-stimulated generation of ROS to inhibit tumor progression and minimize osteolysis in both immunocompetent murine and immunocompromised human MM models.


Assuntos
Mieloma Múltiplo/tratamento farmacológico , Compostos Organometálicos/farmacologia , Osteoclastos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Medula Óssea/metabolismo , Neoplasias Ósseas , Osso e Ossos/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fluordesoxiglucose F18/farmacologia , Humanos , Cadeias alfa de Integrinas/efeitos dos fármacos , Cadeias alfa de Integrinas/metabolismo , Camundongos , Mieloma Múltiplo/metabolismo , Compostos Organometálicos/metabolismo , Osteoclastos/efeitos dos fármacos , Osteólise/patologia , Radioisótopos/farmacologia , Compostos Radiofarmacêuticos/uso terapêutico , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos , Nanomedicina Teranóstica/métodos , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
10.
FASEB J ; 35(9): e21837, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383985

RESUMO

Overwhelming evidence indicates that excessive stimulation of innate immune receptors of the NOD-like receptor (NLR) family causes significant damage to multiple tissues, yet the role of these proteins in bone metabolism is not well known. Here, we studied the interaction between the NLRP3 and NLRC4 inflammasomes in bone homeostasis and disease. We found that loss of NLRP3 or NLRC4 inflammasome attenuated osteoclast differentiation in vitro. At the tissue level, lack of NLRP3, or NLRC4 to a lesser extent, resulted in higher baseline bone mass compared to wild-type (WT) mice, and conferred protection against LPS-induced inflammatory osteolysis. Bone mass accrual in mutant mice correlated with lower serum IL-1ß levels in vivo. Unexpectedly, the phenotype of Nlrp3-deficient mice was reversed upon loss of NLRC4 as bone mass was comparable between WT mice and Nlrp3;Nlrc4 knockout mice. Thus, although bone homeostasis is perturbed to various degrees by the lack of NLRP3 or NLRC4, this tissue appears to function normally upon compound loss of the inflammasomes assembled by these receptors.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Reabsorção Óssea/metabolismo , Osso e Ossos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Diferenciação Celular/fisiologia , Homeostase/fisiologia , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoclastos/metabolismo , Osteólise/metabolismo
11.
Nat Commun ; 12(1): 4974, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404802

RESUMO

Osteoporosis affects millions worldwide and is often caused by osteoclast induced bone loss. Here, we identify the cytoplasmic protein ELMO1 as an important 'signaling node' in osteoclasts. We note that ELMO1 SNPs associate with bone abnormalities in humans, and that ELMO1 deletion in mice reduces bone loss in four in vivo models: osteoprotegerin deficiency, ovariectomy, and two types of inflammatory arthritis. Our transcriptomic analyses coupled with CRISPR/Cas9 genetic deletion identify Elmo1 associated regulators of osteoclast function, including cathepsin G and myeloperoxidase. Further, we define the 'ELMO1 interactome' in osteoclasts via proteomics and reveal proteins required for bone degradation. ELMO1 also contributes to osteoclast sealing zone on bone-like surfaces and distribution of osteoclast-specific proteases. Finally, a 3D structure-based ELMO1 inhibitory peptide reduces bone resorption in wild type osteoclasts. Collectively, we identify ELMO1 as a signaling hub that regulates osteoclast function and bone loss, with relevance to osteoporosis and arthritis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doenças Ósseas Metabólicas/metabolismo , Osteoclastos/metabolismo , Osteoporose/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Animais , Artrite/patologia , Reabsorção Óssea/metabolismo , Sistemas CRISPR-Cas , Feminino , Camundongos , Camundongos Knockout , Osteoprotegerina/deficiência , Ovariectomia , Transcriptoma , Microtomografia por Raio-X
12.
J Leukoc Biol ; 110(3): 433-447, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34254348

RESUMO

As one of the first arriving immune cells after dental implantation, Mϕs own the abilities to polarize into to a spectrum of diverse phenotypes, from "classically activated" M1 Mϕs to "alternatively activated" M2 Mϕs. Herein, it was hypothesized that Mϕ phenotypes dynamically adapt after dental implantation, and the changes ensue a cascade of coordinated interplay with the bone-forming osteoblast and the bone-resorbing osteoclast. Results showed that the remodelling process after dental implantation was similar with the standard response to tissue injury (exampled by tooth extraction models), only with the delay of bone regeneration phases. Additionally, Mϕ activation in both groups underwent a transition from M1 Mϕs dominated to M2-type dominated stage, but the persistence of M1 Mϕs occurred in rat model of dental implantation. Further research in vitro showed that M1 Mϕs are involved in osteoclast activities via secreting the highest levels of TNF-α and IL-1ß, as well as being the potential precursor of osteoclasts. Besides, they also recruited BMSCs by secreting the highest levels of chemoattractants, CCL2 and VEGF. M2 Mϕs accelerated osteogenesis in the subsequent stage via their capability to secrete osteogenesis-related proteins, BMP-2 and TGF-ß1. However, the osteogenic differentiation of BMSCs was inhibited when cultured in a high concentration of conditioned media from each Mϕ phenotype, meaning that the immune strategies should be controlled within the proper ranges. These results suggest that coordinated efforts by both M1 and M2 Mϕs for bone remodelling, which may highlight an optimization strategy for tissue engineering implants.


Assuntos
Processo Alveolar/patologia , Remodelação Óssea , Polaridade Celular , Microambiente Celular , Implantação Dentária , Macrófagos/patologia , Animais , Regeneração Óssea , Diferenciação Celular , Proliferação de Células , Masculino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Modelos Animais , Osteoclastos/metabolismo , Osteogênese , Fenótipo , Células RAW 264.7 , Ratos Sprague-Dawley , Titânio , Extração Dentária
13.
Cell Mol Life Sci ; 78(17-18): 6087-6104, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34296319

RESUMO

Different types of multinucleated giant cells (MGCs) of myeloid origin have been described; osteoclasts are the most extensively studied because of their importance in bone homeostasis. MGCs are formed by cell-to-cell fusion, and most types have been observed in pathological conditions, especially in infectious and non-infectious chronic inflammatory contexts. The precise role of the different MGCs and the mechanisms that govern their formation remain poorly understood, likely due to their heterogeneity. First, we will introduce the main populations of MGCs derived from the monocyte/macrophage lineage. We will then discuss the known molecular actors mediating the early stages of fusion, focusing on cell-surface receptors involved in the cell-to-cell adhesion steps that ultimately lead to multinucleation. Given that cell-to-cell fusion is a complex and well-coordinated process, we will also describe what is currently known about the evolution of F-actin-based structures involved in macrophage fusion, i.e., podosomes, zipper-like structures, and tunneling nanotubes (TNT). Finally, the localization and potential role of the key fusion mediators related to the formation of these F-actin structures will be discussed. This review intends to present the current status of knowledge of the molecular and cellular mechanisms supporting multinucleation of myeloid cells, highlighting the gaps still existing, and contributing to the proposition of potential disease-specific MGC markers and/or therapeutic targets.


Assuntos
Adesão Celular , Células Gigantes/metabolismo , Células Mieloides/metabolismo , Podossomos/metabolismo , Células Gigantes/citologia , Humanos , Integrinas/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Células Mieloides/citologia , Células Mieloides/ultraestrutura , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese , Receptores Imunológicos/metabolismo
14.
Front Immunol ; 12: 651049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276648

RESUMO

Objective: Autoantibodies are detected in most patients with rheumatoid arthritis (RA) and can be of the IgM, IgG or IgA subclass. Correlations between IgA autoantibodies and more severe disease activity have been previously reported, but the functional role of IgA autoantibodies in the pathogenesis of RA is ill understood. In this study, we explored the effect of IgA immune complexes on osteoclast mediated bone resorption. Methods: Anti-citrullinated peptide antibody (ACPA) and anti-carbamylated protein (anti-CarP) antibody levels of the IgA and IgG isotype and rheumatoid factor (RF) IgA were determined in synovial fluid (SF) of RA patients. Monocytes, neutrophils, and osteoclasts were stimulated with precipitated immune complexes from SF of RA patients or IgA- and IgG-coated beads. Activation was determined by neutrophil extracellular trap (NET) release, cytokine secretion, and bone resorption. Results: NET formation by neutrophils was enhanced by SF immune complexes compared to immune complexes from healthy or RA serum. Monocytes stimulated with isolated SF immune complexes released IL-6 and IL-8, which correlated with the levels of ACPA IgA levels in SF. Osteoclasts cultured in the presence of supernatant of IgA-activated monocytes resorbed significantly more bone compared to osteoclasts that were cultured in supernatant of IgG-activated monocytes (p=0.0233). Osteoclasts expressed the Fc receptor for IgA (FcαRI; CD89) and Fc gamma receptors. IgA-activated osteoclasts however produced significantly increased levels of IL-6 (p<0.0001) and IL-8 (p=0.0007) compared to IgG-activated osteoclasts. Both IL-6 (p=0.03) and IL-8 (p=0.0054) significantly enhanced bone resorption by osteoclasts. Conclusion: IgA autoantibodies induce release of IL-6 and IL-8 by immune cells as well as osteoclasts, which enhances bone resorption by osteoclasts. We anticipate that this will result in more severe disease activity in RA patients. Targeting IgA-FcαRI interactions therefore represents a promising novel therapeutic strategy for RA patients with IgA autoantibodies.


Assuntos
Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Reabsorção Óssea/imunologia , Imunoglobulina A/imunologia , Osteoclastos/imunologia , Animais , Complexo Antígeno-Anticorpo/imunologia , Artrite Reumatoide/sangue , Artrite Reumatoide/patologia , Reabsorção Óssea/sangue , Reabsorção Óssea/patologia , Bovinos , Armadilhas Extracelulares/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Articulação do Joelho/imunologia , Articulação do Joelho/patologia , Osteoclastos/metabolismo , Líquido Sinovial/imunologia
15.
Cell Death Dis ; 12(7): 662, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215717

RESUMO

Bone is a frequent metastatic site of non-small cell lung cancer (NSCLC), and bone metastasis (BoM) presents significant challenges for patient survival and quality of life. Osteolytic BoM is characterised by aberrant differentiation and malfunction of osteoclasts through modulation of the TGF-ß/pTHrP/RANKL signalling pathway, but its upstream regulatory mechanism is unclear. In this study, we found that lncRNA-SOX2OT was highly accumulated in exosomes derived from the peripheral blood of NSCLC patients with BoM and that patients with higher expression of exosomal lncRNA-SOX2OT had significantly shorter overall survival. Additionally, exosomal lncRNA-SOX2OT derived from NSCLC cells promoted cell invasion and migration in vitro, as well as BoM in vivo. Mechanistically, we discovered that NSCLC cell-derived exosomal lncRNA-SOX2OT modulated osteoclast differentiation and stimulated BoM by targeting the miRNA-194-5p/RAC1 signalling axis and TGF-ß/pTHrP/RANKL signalling pathway in osteoclasts. In conclusion, exosomal lncRNA-SOX2OT plays a crucial role in promoting BoM and may serve as a promising prognostic biomarker and treatment target in metastatic NSCLC.


Assuntos
Neoplasias Ósseas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Movimento Celular , Exossomos/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Osteoclastos/metabolismo , RNA Longo não Codificante/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Células A549 , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Exossomos/genética , Exossomos/transplante , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Neuropeptídeos , Osteoclastos/patologia , Células RAW 264.7 , RNA Longo não Codificante/genética , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/genética
16.
Dev Biol ; 478: 133-143, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34245724

RESUMO

Vascular endothelial growth factor A (VEGF-A) is expressed by several cell types and is a crucial factor for angiogenic-osteogenic coupling. However, the immunolocalization of VEGF-A during the early stages of the alveolar process formation remains underexplored. Thus, we analyzed the spatio-temporal immunolocalization of VEGF-A and its relationship with Runt-related transcription factor 2 (Runx2) and osterix (Osx) during the early steps of intramembranous ossification of the alveolar process in rat embryos. Embryo heads (E) of 16, 18 and 20-day-old rats were processed for paraffin embedding. Histomorphometry and immunohistochemistry to detect VEGF-A, Runx2, and Osx (osteoblast differentiation markers) were performed. The volume density of bone tissue including bone cells and blood vessels increased significantly in E18 and E20. Cells showing high VEGF-A immunoreactivity were initially observed within a perivascular niche in the ectomesenchyme; afterwards, these cells were diffusely located near bone formation sites. Runx2-and Osx-immunopositive cells were observed in corresponded regions of cells showing strong VEGF-A immunoreactivity. Although these immunostained cells were observed in all specimens, this immunolocalization pattern was more evident in E16 specimens and gradually decreased in E18 and E20 specimens. Double immunofluorescence labelling showed intracellular co-localization of Osx and VEGF-A in cells surrounding the developing alveolar process, indicating a crucial role of VEGF-A in osteoblast differentiation. Our results showed VEGF-A immunoexpression in osteoblasts and its precursors during the maxillary alveolar process formation of rat embryos. Moreover, the VEGF-A-positive cells located within a perivascular niche at the early stages of the alveolar process development suggest a crosstalk between endothelium and ectomesenchymal cells, reinforcing the angiogenic-osteogenic coupling in this process.


Assuntos
Processo Alveolar/embriologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Osteoblastos/metabolismo , Osteogênese , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Processo Alveolar/citologia , Processo Alveolar/metabolismo , Animais , Células Endoteliais/metabolismo , Imunofluorescência , Técnicas Imunoenzimáticas , Mesoderma/citologia , Mesoderma/metabolismo , Osteoblastos/citologia , Osteoclastos/metabolismo , Ratos , Ratos Wistar
17.
Mol Immunol ; 137: 187-200, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34274794

RESUMO

Aging is associated with excessive bone loss that is not counteracted with the development of new bone. However, the mechanisms underlying age-related bone loss are not completely clear. Myeloid-derived suppressor cells (MDSCs) are a population of heterogenous immature myeloid cells with immunosuppressive functions that are known to stimulate tumor-induced bone lysis. In this study, we investigated the association of MDSCs and age-related bone loss in mice. Our results shown that aging increased the accumulation of MDSCs in the bone marrow and spleen, while in the meantime potentiated the osteoclastogenic activity of the CD11b+Ly6ChiLy6G+ monocytic subpopulation of MDSCs. In addition, CD11b+Ly6ChiLy6G+ MDSCs from old mice exhibited increased expression of c-fms compared to young mice, and were more sensitive to RANKL-induced osteoclast gene expression. On the other hand, old mice showed elevated production of IL-6 and receptor activator of nuclear factor kappa-B ligand (RANKL) in the circulation. Furthermore, IL-6 and RANKL were able to induce the proliferation of CD11b+Ly6ChiLy6G+ MDSCs and up-regulate c-fms expression. Moreover, CD11b+Ly6ChiLy6G+ MDSCs obtained from old mice showed increased antigen-specific T cell suppressive function, pStat3 expression, and cytokine production in response to inflammatory stimulation, compared to those cells obtained from young mice. Our findings suggest that CD11b+Ly6ChiLy6G+ MDSCs are a source of osteoclast precursors that together with the presence of persistent, low-grade inflammation, contribute to age-associated bone loss in mice.


Assuntos
Envelhecimento/fisiologia , Células Mieloides/fisiologia , Células Supressoras Mieloides/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Envelhecimento/metabolismo , Animais , Antígenos Ly/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Expressão Gênica/fisiologia , Inflamação/metabolismo , Inflamação/patologia , Ativação Linfocitária/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/metabolismo , Monócitos/fisiologia , Células Mieloides/metabolismo , Células Supressoras Mieloides/metabolismo , Osteoclastos/metabolismo , Baço/metabolismo , Baço/fisiologia
18.
Clin Interv Aging ; 16: 1357-1366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290498

RESUMO

Background: Studies have found the pivotal role of miRNAs in the progression of postmenopausal osteoporosis (OP). However, the function of miRNAs in OP is unclear. This study aimed to explore the biological functions of microRNA-151a-3p in OP. Methods: RT-qPCR was employed to assess the expression of microRNA-151a-3p in serum isolated from OP patients and healthy controls. Dual-energy X-ray absorptiometry (DXA) was used to measure the bone mineral density (BMD) of the lumbar spine. The expression levels of c-Fos, NFATc1, and TRAP were tested by Western blot. Ovariectomized (OVX) rats were treated with antago microRNA-151a-3p or antago NC, and then serum and lumbar vertebrae were collected for ELISA and bone histomorphology analysis. Results: The expression of microRNA-151a-3p in postmenopausal women with osteoporosis was significantly up-regulated, and microRNA-151a-3p level was negatively correlated with BMD. During osteoclastogenesis, microRNA-151a-3p level was obviously increased. Overexpression of microRNA-151a-3p promoted the differentiation of RANKL-induced THP-1 and RAW264.7 cells into osteoclasts, whereas silencing of microRNA-151a-3p resulted in the opposite results. Silencing of microRNA-151a-3p in OVX rats altered osteoclastogenesis-related factors and raised BMD. Conclusion: MicroRNA-151a-3p could partly regulate osteoporosis by promoting osteoclast differentiation, and miRNA-151a-3p could be a potential therapeutic target for postmenopausal osteoporosis.


Assuntos
Diferenciação Celular , MicroRNAs/metabolismo , Osteoclastos/metabolismo , Osteoporose Pós-Menopausa/sangue , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/terapia , Ratos
19.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200172

RESUMO

Megakaryocytes (MKs) differentiate from hematopoietic stem cells and produce platelets at the final stage of differentiation. MKs directly interact with bone cells during bone remodeling. However, whether MKs are involved in regulating bone metabolism through indirect regulatory effects on bone cells is unclear. Here, we observed increased osteoclast differentiation of bone marrow-derived macrophages (BMMs) cultured in MK-cultured conditioned medium (MK CM), suggesting that this medium contains factors secreted from MKs that affect osteoclastogenesis. To identify the MK-secreted factor, DNA microarray analysis of the human leukemia cell line K562 and MKs was performed, and S100 calcium-binding protein P (S100P) was selected as a candidate gene affecting osteoclast differentiation. S100P was more highly expressed in MKs than in K562 cells, and showed higher levels in MK CM than in K562-cultured conditioned medium. In BMMs cultured in the presence of recombinant human S100P protein, osteoclast differentiation was promoted and marker gene expression was increased. The resorption area was significantly larger in S100P protein-treated osteoclasts, demonstrating enhanced resorption activity. Overall, S100P secreted from MKs promotes osteoclast differentiation and resorption activity, suggesting that MKs indirectly regulate osteoclast differentiation and activity through the paracrine action of S100P.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Diferenciação Celular , Megacariócitos/metabolismo , Proteínas de Neoplasias/metabolismo , Osteoclastos/citologia , Osteogênese , Proteínas de Ligação ao Cálcio/genética , Células Cultivadas , Humanos , Células K562 , Megacariócitos/citologia , Proteínas de Neoplasias/genética , Osteoclastos/metabolismo
20.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201781

RESUMO

We recently reported an unexpected role of osteoblast-derived matrix vesicles in the delivery of microRNAs to bone matrix. Of such microRNAs, we found that miR-125b inhibited osteoclast formation by targeting Prdm1 encoding a transcriptional repressor of anti-osteoclastogenesis factors. Transgenic (Tg) mice overexpressing miR-125b in osteoblasts by using human osteocalcin promoter grow normally but exhibit high trabecular bone mass. We have now further investigated the effects of osteoblast-mediated miR-125b overexpression on skeletal morphogenesis and remodeling during development, aging and in a situation of skeletal repair, i.e., fracture healing. There were no significant differences in the growth plate, primary spongiosa or lateral (periosteal) bone formation and mineral apposition rate between Tg and wild-type (WT) mice during early bone development. However, osteoclast number and medial (endosteal) bone resorption were less in Tg compared to WT mice, concomitant with increased trabecular bone mass. Tg mice were less susceptible to age-dependent changes in bone mass, phosphate/amide I ratio and mechanical strength. In a femoral fracture model, callus formation progressed similarly in Tg and WT mice, but callus resorption was delayed, reflecting the decreased osteoclast numbers associated with the Tg callus. These results indicate that the decreased osteoclastogenesis mediated by miR-125b overexpression in osteoblasts leads to increased bone mass and strength, while preserving bone formation and quality. They also suggest that, in spite of the fact that single miRNAs may target multiple genes, the miR-125b axis may be an attractive therapeutic target for bone loss in various age groups.


Assuntos
Desenvolvimento Ósseo , Reabsorção Óssea/patologia , MicroRNAs/genética , Osteoblastos/patologia , Osteoclastos/patologia , Osteogênese , Fatores Etários , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo
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