Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 678
Filtrar
1.
PLoS One ; 15(8): e0238132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853221

RESUMO

Bears do not suffer from osteoporosis during hibernation, which is associated with long-term inactivity, lack of food intake, and cold exposure. However, the mechanisms involved in bone loss prevention have scarcely been elucidated in bears. We investigated the effect of serum from hibernating Japanese black bears (Ursus thibetanus japonicus) on differentiation of peripheral blood mononuclear cells (PBMCs) to osteoclasts (OCs). PBMCs collected from 3 bears were separately cultured with 10% serum of 4 active and 4 hibernating bears (each individual serum type was assessed separately by a bear PBMCs), and differentiation were induced by treatment with macrophage colony stimulating factor (M-CSF) and receptor activator of NF-kB ligand (RANKL). PBMCs that were cultured with the active bear serum containing medium (ABSM) differentiated to multi-nucleated OCs, and were positive for TRAP stain. However, cells supplemented with hibernating bear serum containing medium (HBSM) failed to form OCs, and showed significantly lower TRAP stain (p < 0.001). On the other hand, HBSM induced proliferation of adipose derived mesenchymal stem cells (ADSCs) similarly to ABSM (p > 0.05), indicating no difference on cell growth. It was revealed that osteoclastogenesis of PBMCs is hindered by HBSM, implying an underlying mechanism for the suppressed bone resorption during hibernation in bears. In addition, this study for the first time showed the formation of bears' OCs in-vitro.


Assuntos
Hibernação/fisiologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Ursidae/fisiologia , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/fisiopatologia , Diferenciação Celular/fisiologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/fisiologia , Fator Estimulador de Colônias de Macrófagos/metabolismo , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Osteoclastos/metabolismo , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Ursidae/metabolismo
2.
Am J Physiol Endocrinol Metab ; 318(6): E866-E877, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32315212

RESUMO

The receptor activator of nuclear factor-κB (NF-κB) (RANK), its ligand (RANKL), and the decoy receptor osteoprotegerin (OPG) are a triad of proteins that regulate bone metabolism, and serum OPG is considered a biomarker for cardiovascular diseases and Type 2 diabetes; however, the implications of OPG in adipose tissue metabolism remains elusive. In this study, we investigate RANK-RANKL-OPG signaling in white adipose tissue browning. Histological analysis of osteoprotegerin knockout (OPG-/-) mice showed subcutaneous white adipose tissue (sWAT) browning, resistance for high-fat diet-induced weight gain, and preserved glucose metabolism compared with wild-type (WT) mice. Stromal vascular fraction (SVF) cells from sWAT of OPG-/- mice showed multilocular morphology and higher expression of brown adipocyte marker genes compared with those from the WT group. Infusion of RANKL induced browning and elevated respiratory rates in sWAT, along with increased whole body oxygen consumption in mice measured by indirect calorimetry. Subcutaneous WAT-derived SVF and 3T3-L1 cells, but not mature white adipocytes, differentiated into beige adipose tissue in the presence of RANKL. Moreover, SVF cells, even under white adipocyte differentiation, showed multilocular lipid droplet, lower lipid content, and increased expression of beige adipocyte markers with RANKL stimulation. In this study, we show for the first time the contribution of RANKL to increase energy expenditure by inducing beige adipocyte differentiation in preadipocytes.


Assuntos
Adipócitos Bege/metabolismo , Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Obesidade/metabolismo , Osteoprotegerina/genética , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Células 3T3-L1 , Adipócitos Bege/citologia , Adipócitos Bege/ultraestrutura , Adipócitos Brancos/citologia , Adipócitos Brancos/metabolismo , Adipócitos Brancos/ultraestrutura , Tecido Adiposo Bege/citologia , Tecido Adiposo Bege/metabolismo , Tecido Adiposo Branco/citologia , Animais , Calorimetria Indireta , Dieta Hiperlipídica , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Gotículas Lipídicas/ultraestrutura , Camundongos , Camundongos Knockout , Osteoprotegerina/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/genética , Ligante RANK/farmacologia , Transdução de Sinais , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/metabolismo , Ganho de Peso/efeitos dos fármacos , Ganho de Peso/genética
3.
Toxicology ; 436: 152429, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32156525

RESUMO

Excessive systemic uptake of inorganic fluorides causes disturbances of bone homeostasis. The mechanism of skeletal fluorosis is still uncertain. This study aimed to study the effect of fluoride on osteocyte-driven osteoclastogenesis and probe into the role of PTH in this process. IDG-SW3 cells seeded in collagen-coated constructs were developed into osteocyte-like cells through induction of mineral agents. Then, osteocyte-like cells were exposed to fluoride in the presence or absence of parathyroid hormone (PTH). Cell viability and their capacity to produce receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and sclerostin (SOST) were detected by MTT and Western blot assays, respectively. Finally, a transwell coculture system using osteocyte-like cells seeded in the low compartment, and osteoclast precursors added in the inserts was developed to observe the osteocyte-driven osteoclasogenesis response to fluoride with or without PTH, and the expression of molecules involved in this mechanism were measure by real time RT-PCR. Results showed that osteocytes withstood a toxic dose of fluoride, and yet PTH administration significantly reduced osteocytes viability. PTH amplified the effect of fluoride on the expression of osteoclastogenesis-related molecules in osteocyte, but did not enlarged the stimulating effect of fluoride on osteoclastogenesis drove by osteocyte coculture. Gene expression levels of TRAP, RANK, JNK and NFAtc1 significantly increased in fluoride affected osteoclast precursor cocultured with osteocyte-like cells. The impact of fluoride on osteocyte-driven osteoclast differentiation was stronger than that of PTH. In conclusion, osteocyte played a pivotal role on the mechanism underlying fluoride-affected osteoclastogenesis in which RANK-JNK-NFATc1 signaling pathway was involved, and PTH had a significant impact in this process.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteócitos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteócitos/metabolismo , Osteócitos/patologia , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Hormônio Paratireóideo/farmacologia , Ligante RANK/genética , Ligante RANK/metabolismo , Células RAW 264.7 , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais , Fosfatase Ácida Resistente a Tartarato/genética , Fosfatase Ácida Resistente a Tartarato/metabolismo
4.
Arch Oral Biol ; 112: 104670, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32058859

RESUMO

OBJECTIVES: To investigate the regulation of inflammatory and osteoclastogenic signaling by 5-lipoxygenase (5-LO) in apical periodontitis induced by oral contamination of dental root canals in mice. DESIGN: Apical periodontitis was induced in 5-lipoxygenase enzyme knockout (129-Alox5tm1Fun) and 129 wild-type mice (n = 96) by exposure of the dental root canal to the oral cavity. After 7, 14, 21, and 28 days, the animals were euthanized and the tissues removed (n = 12 teeth per period) for histopathological and histometric analyses (hematoxylin and eosin [HE]), evaluation of osteoclastogenic activity (tartrate-resistant acid phosphatase enzyme [TRAP]), and determination of inflammatory and osteoclastogenic signaling (qRT-PCR). RESULTS: Oral contamination of dental root canals induced recruitment of neutrophils and osteoclasts to the periodontal ligament, resulting in bone resorption. Absence of 5-LO did not impair neutrophil recruitment while osteoclastic formation was increased. Nonetheless, early bone resorption progressed similarly to lesions in wild-type animals. Interestingly, in the absence of 5-LO, the synthesis of mRNAs for cytokines, chemokines, and their receptors was significantly reduced while that of regulators of osteoclastogenesis (RANK, RANKL, and OPG) was increased in comparison with the corresponding levels in wild-type animals. CONCLUSIONS: The 5-LO pathway plays a role in the stimulation of inflammatory mediator synthesis and inhibition of osteoclastogenesis in apical periodontitis in mice. However, the paradoxical inflammatory-osteoclastogenic signaling did not impair inflammatory cell recruitment and bone resorption during early development of the disease.


Assuntos
Araquidonato 5-Lipoxigenase/genética , Reabsorção Óssea , Osteogênese , Osteoprotegerina/metabolismo , Periodontite Periapical/genética , Animais , Inflamação , Camundongos , Camundongos Knockout , Osteoclastos , Periodontite Periapical/fisiopatologia , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo
5.
Scand J Immunol ; 91(5): e12874, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32090353

RESUMO

The immune and skeletal systems share common mechanisms, and the crosstalk between the two has been termed osteoimmunology. Osteoimmunology mainly focuses on diseases between the immune and bone systems including bone loss diseases, and imbalances in osteoimmune regulation affect skeletal homeostasis between osteoclasts and osteoblasts. The immune mediator interleukin-20 (IL-20), a member of the IL-10 family, enhances inflammation, chemotaxis and angiogenesis in diseases related to bone loss. However, it is unclear how IL-20 regulates the balance between osteoclastogenesis and osteoblastogenesis; therefore, we explored the mechanisms by which IL-20 affects bone mesenchymal stem cells (BMSCs) in osteoclastogenesis in primary cells during differentiation, proliferation, apoptosis and signalling. We initially found that IL-20 differentially regulated preosteoclast proliferation and apoptosis; BMSC-conditioned medium (CM) significantly enhanced osteoclast formation and bone resorption, which was dose-dependently regulated by IL-20; IL-20 inhibited OPG expression and promoted M-CSF, RANKL and RANKL/OPG expression; and IL-20 differentially regulated the expression of osteoclast-specific gene and transcription factors through the OPG/RANKL/RANK axis and the NF-kB, MAPK and AKT pathways. Therefore, IL-20 differentially regulates BMSCs in osteoclastogenesis and exerts its function by activating the OPG/RANKL/RANK axis and the NF-κB, MAPK and AKT pathways, which make targeting IL-20 a promising direction for targeted regulation in diseases related to bone loss.


Assuntos
Interleucinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Osteoprotegerina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais , Animais , Apoptose/genética , Diferenciação Celular , Proliferação de Células , Regulação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Ratos
6.
Nat Commun ; 11(1): 234, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932605

RESUMO

Microfold cells (M cells) are responsible for antigen uptake to initiate immune responses in the gut-associated lymphoid tissue (GALT). Receptor activator of nuclear factor-κB ligand (RANKL) is essential for M cell differentiation. Follicle-associated epithelium (FAE) covers the GALT and is continuously exposed to RANKL from stromal cells underneath the FAE, yet only a subset of FAE cells undergoes differentiation into M cells. Here, we show that M cells express osteoprotegerin (OPG), a soluble inhibitor of RANKL, which suppresses the differentiation of adjacent FAE cells into M cells. Notably, OPG deficiency increases M cell number in the GALT and enhances commensal bacterium-specific immunoglobulin production, resulting in the amelioration of disease symptoms in mice with experimental colitis. By contrast, OPG-deficient mice are highly susceptible to Salmonella infection. Thus, OPG-dependent self-regulation of M cell differentiation is essential for the balance between the infectious risk and the ability to perform immunosurveillance at the mucosal surface.


Assuntos
Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Osteoprotegerina/metabolismo , Animais , Anticorpos Antibacterianos/imunologia , Ceco/citologia , Ceco/imunologia , Ceco/metabolismo , Ceco/microbiologia , Diferenciação Celular , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Microbioma Gastrointestinal/imunologia , Homeostase , Imunidade nas Mucosas , Imunoglobulina G/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Tecido Linfoide/citologia , Tecido Linfoide/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoprotegerina/genética , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Salmonella typhimurium/patogenicidade , Transdução de Sinais
8.
J Cardiovasc Pharmacol ; 75(3): 200-207, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31868826

RESUMO

Nuclear factor of activated T cell cytoplasmic 1 (NFATc1), a crucial member of the transcription factor NFAT family, is indispensable in the immune system and the morphogenesis of cardiac valves and septa and is also vital in osteoclasts and atherosclerotic calcification. Currently, osteoporosis and vascular diseases are severely hazardous to health and quality of life, and the 2 conditions always coincide with each other. The bone-vascular axis calcification paradox serves as a bridge between bone and vascular diseases, linking these 2 seemingly separate diseases, and the receptor activator of NF-κB (RANK)/receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) system may be the common mechanism of the bone-vascular axis calcification paradox. NFATc1 provides a new therapeutic target for bone and vascular diseases. However, the specific mechanism by which NFATc1 acts on the bone-vascular axis calcification paradox, whether NFATc1 is related to the RANK/RANKL/OPG system, and how to use NFATc1 as a therapeutic target to avoid its side effects in other systems requires further study.


Assuntos
Artérias/metabolismo , Aterosclerose/metabolismo , Remodelação Óssea , Fatores de Transcrição NFATC/metabolismo , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Calcificação Vascular/metabolismo , Animais , Artérias/patologia , Aterosclerose/patologia , Humanos , Osteoblastos/patologia , Osteoclastos/patologia , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais , Calcificação Vascular/patologia
9.
J Cell Physiol ; 235(1): 599-610, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271661

RESUMO

Nutritional factors influence bone development. Previous studies demonstrated that bone mass significantly increased with suppressed bone resorption in early life of rats fed with AIN-93G semi-purified diets supplemented with 10% whole blueberry (BB) powder for 2 weeks. However, the effects of increased phenolic acids in animal serum due to this diet on bone and bone resorption were unclear. This in vitro and in ex vivo study examined the effects of phenolic hippuric acid (HA) and 3-(3-hydroxyphenyl) propionic acid (3-3-PPA) on osteoclastic cell differentiation and bone resorption. We cultured murine osteoclast (macrophage) cell line, RAW 264.7 cells, and hematopoietic osteoclast progenitor cells (isolated from 4-week-old C57BL6/J mice) with 50 ng/ml of receptor activator of nuclear factor κ-Β ligand (RANKL). Morphologic studies showed decreased osteoclast number with treatment of 2.5% mouse serum from BB diet-fed animals compared with those treated with serum from standard casein diet-fed mice in both RAW 264.7 cell and primary cell cultures. HA and 3-3-PPA, but not 3-4-PPA, had dose-dependent suppressive effects on osteoclastogenesis and osteoclast resorptive activity in Corning osteo-assay plates. Signaling pathway analysis showed that after pretreatment with HA or 3-3-PPA, RANKL-stimulated increase of osteoclastogenic markers, such as nuclear factor of activated T-cells, cytoplasmic 1 and matrix metallopeptidase 9 gene/protein expression were blunted. Inhibitory effects of HA and 3-3-PPA on osteoclastogenesis utilized RANKL/RANK independent mediators. The study revealed that HA and 3-3-PPA significantly inhibited osteoclastogenesis and bone osteoclastic resorptive activity.


Assuntos
Hipuratos/farmacologia , Osteogênese/efeitos dos fármacos , Fenóis/farmacologia , Propionatos/farmacologia , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Animais , Células da Medula Óssea/citologia , Reabsorção Óssea/tratamento farmacológico , Linhagem Celular , AMP Cíclico/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Osteogênese/fisiologia , Células RAW 264.7 , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
J Trace Elem Med Biol ; 57: 126417, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31653549

RESUMO

BACKGROUND: To this day, empirical data suggests that zinc has important roles in matrix synthesis, bone turnover, and mineralization and its beneficial effects on bone could be mediated through different mechanisms. The influence of zinc on bone turnover could be facilitated via regulating RANKL/RANK/OPG pathway in bone tissue. Therefore, the aim of the study was to conduct a review to investigate the possible effect of the zinc mediated bone remodeling via RANKL/RANK/OPG pathway. METHODS: A comprehensive systematic search was performed in MEDLINE/PubMed, Cochrane Library, SCOPUS, and Google Scholar to explore the studies investigating the effect of zinc as a bone remodeling factor via RANKL/RANK/OPG pathway regulation. Subsequently, the details of the pathway and the impact of zinc supplements on RANKL/RANK/OPG pathway regulation were discussed. RESULTS: The pathway could play an important role in bone remodeling and any imbalance between RANKL/RANK/OPG components could lead to extreme bone resorption. Although the outcomes of some studies are equivocal, it is evident that zinc possesses protective properties against bone loss by regulating the RANKL/RANK/OPG pathway. There are several experiments where zinc supplementation resulted in upregulation of OPG expression or decreases RANKL level. However, the results of some studies oppose this. CONCLUSION: It is likely that sufficient zinc intake will elicit positive effects on bone health by RANKL/RANK/OPG regulation. Although the outcomes of a few studies are equivocal, it seems that zinc can exert the protective properties against bone loss by suppressing osteoclastogenesis via downregulation of RANKL/RANK. Additionally, there are several experiments where zinc supplementation resulted in upregulation of OPG expression. However, the results of limited studies oppose this. Therefore, aside from the positive role zinc possesses in preserving bone mass, further effects of zinc in RANKL/RANK/OPG system requires further animal/human studies.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Zinco/uso terapêutico , Animais , Densidade Óssea/efeitos dos fármacos , Humanos
11.
Breast Cancer Res ; 21(1): 132, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796128

RESUMO

BACKGROUND: ERBB-2 is overexpressed in about 20% of breast cancers (BCs), indicating poor prognosis. The receptor activator of nuclear factor-κB (RANK) pathway is implicated in ERBB-2 (+) BC. The purpose of this study was to elucidate the underlying molecular mechanism of this interaction and the beneficial impact of dual targeting of RANK and ERBB-2 pathways. METHODS: We used SKBR3, MCF7, MDA-MB-453, and BT-474 human BC cell lines. We examined RANK and RANKL expression using RT-PCR, Western blot, and immunofluorescence. The evaluation of RANK expression in a cohort of BC patients was performed using immunohistochemistry. The interaction between RANK and ERBB family members was detected using proximity ligation assay (PLA), which enables the visualization of interacting proteins. We used inhibitors of both pathways [trastuzumab (T), pertuzumab (P), denosumab (D)]. NF-κB pathway activation was studied using Western blot. Cell growth and viability was evaluated using XTT, flow cytometry, and clonogenic assay. For cell migration evaluation, scratch assay was performed. Data were analyzed by one-way ANOVA. RESULTS: Cell lines express RANK and RANKL. RANK immunostaining was also detected in human BC tissue samples. RANK receptor dimerizes with ERBB family members. RANK/ERBB-2 dimer number seems to be associated with ERBB-2 expression (SKBR3, 5.4; BT-474, 8.2; MCF7, 0.7; MDA-MB-453, 0.3). RANK/ERBB-2 dimers were decreased in the presence of the inhibitors D, T, and P, while they were increased after RANKL (R) treatment in SKBR3 (m, 5.4; D, 1.2; T, 1.9; DT, 0.6; TP, 1; DTP, 0.4; R, 11.8) and BT-474 (m, 8.2; D, 3.1; T, 4.3; DT, 0.7; TP, 3.4; DTP, 3.2; R, 11.6). Combination targeting of SKBR3 further decreased NF-κB pathway activation compared to single targeting. In SKBR3, RANKL and ERBB-2 blockage resulted in reduced cell proliferation, increased apoptosis, and lower metastatic potential compared to mock cells (m) and reversed values in RANKL presence. The combination treatment of SKBR3 with D, T, and P had an advantage in functional traits compared to single targeting. Denosumab suppressed NF-κB signaling and diminished proliferation rate in MDA-MB-453 cells. MCF7 did not correspond to inhibitors. CONCLUSIONS: The results indicate a novel physical and molecular association between ERBB-2 and RANK pathways that affects ERBB-2 (+) BC growth. We also present data suggesting that the combination of anti-ERBB-2 agents and RANKL inhibitors have a potential direct anti-tumor effect and should be further tested in certain BC patients.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias da Mama/metabolismo , Receptores ErbB/antagonistas & inibidores , Terapia de Alvo Molecular , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/antagonistas & inibidores , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células Cultivadas , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Ligante RANK/genética , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Int J Mol Sci ; 20(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546898

RESUMO

Cartilage and the bordering subchondral bone form a functionally active regulatory interface with a prominent role in osteoarthritis pathways. The Wnt and the OPG-RANKL-RANK signaling systems, as key mediators, interact in subchondral bone remodeling. Osteoarthritic osteoblasts polarize into two distinct phenotypes: a low secretory and an activated, pro-inflammatory and anti-resorptive subclass producing high quantities of IL-6, PGE2, and osteoprotegerin, but low levels of RANKL, thus acting as putative effectors of subchondral bone sclerosis. Wnt agonists, Wnt5a, Wisp-1 initiate excessive bone remodeling, while Wnt3a and 5a simultaneously cause loss of proteoglycans and phenotype shift in chondrocytes, with decreased expression of COL2A, aggrecan, and Sox-9. Sclerostin, a Wnt antagonist possesses a protective effect for the cartilage, while DKK-1 inhibits VEGF, suspending neoangiogenesis in the subchondral bone. Experimental conditions mimicking abnormal mechanical load, the pro-inflammatory milieu, but also a decreased OPG/RANKL ratio in the cartilage, trigger chondrocyte apoptosis and loss of the matrix via degradative matrix metalloproteinases, like MMP-13 or MMP-9. Hypoxia, an important cofactor exerts a dual role, promoting matrix synthesis via HIF-1α, a Wnt silencer, but turning on HIF-2α that enhances VEGF and MMP-13, along with aberrant collagen expression and extracellular matrix deterioration in the presence of pro-inflammatory cytokines.


Assuntos
Osso e Ossos/metabolismo , Cartilagem Articular/metabolismo , Osteoartrite/metabolismo , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Animais , Osso e Ossos/patologia , Cartilagem Articular/patologia , Humanos , Osteoartrite/patologia
13.
Semin Immunopathol ; 41(5): 551-563, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31506868

RESUMO

Emerging evidence suggest that macrophage and osteoclast are two competing differentiation outcomes from myeloid progenitors. In this review, we summarize recent advances in the understanding of the molecular mechanisms controlling the polarization of macrophage and osteoclast. These include nuclear receptors/transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ) and estrogen-related receptor α (ERRα), their transcription cofactor PPARγ coactivator 1-ß (PGC-1ß), metabolic factors such as mitochondrial complex I (CI) component NADH:ubiquinone oxidoreductase iron-sulfur protein 4 (Ndufs4), as well as transmembrane receptors such as very-low-density-lipoprotein receptor (VLDLR). These molecular rheostats promote osteoclast differentiation but suppress proinflammatory macrophage activation and inflammation, by acting lineage-intrinsically, systemically or cross generation. These findings provide new insights to the understanding of the interactions between innate immunity and bone remodeling, advancing the field of osteoimmunology.


Assuntos
Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Osteoclastos/imunologia , Osteoclastos/metabolismo , Animais , Biomarcadores , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Humanos , Imunomodulação , Ativação de Macrófagos/genética , Osteogênese/genética , Osteoprotegerina/metabolismo , PPAR gama/metabolismo , Ligante RANK/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptores Estrogênicos/metabolismo , Receptores de LDL/metabolismo , Transdução de Sinais
14.
Mol Biol Rep ; 46(5): 5425-5432, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31364017

RESUMO

Obesity is a complex disorder that is influenced by genetic and environmental factors. DNA methylation is an epigenetic mechanism that is involved in development of obesity and its metabolic complications. The aim of this study was to investigate the association between the RANKL and c-Fos gene methylation on obesity with body mass index (BMI), lipid parameters, homeostasis model assessment of insulin resistance (HOMA-IR), plasma leptin, adiponectin and resistin levels. The study included 68 obese and 46 non-obese subjects. Anthropometric parameters, including body weight, body mass index, waist circumference, and waist-hip ratio, were assessed. Serum glucose, triglycerides (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), plasma leptin, adiponectin and resistin levels were measured. Methylation status of RANKL and c-Fos gen were evaluated by MS-HRM. Statistically significant differences were observed between obese patients and the controls with respect to RANKL and c-Fos gene methylation status (p < 0.001). Also, statistically significant importance was observed RANKL gene methylation and increased level of leptin in obese subjects (p = 0.0081). At the same time, statistically significant association between methylation of c-Fos and increased level of adiponectin was observed in obese patients (p = 0.03) On the other hand, decreased level of resistin was observed where the c-Fos was unmetyladed in controls (p = 0.01). We conclude that methylation of RANKL and c-Fos genes have significant influences on obesity and adipokine levels. Based on literature this was the first study which shows the interactions between RANKL and c-Fos methylation and obesity.


Assuntos
Epigênese Genética/genética , Regulação da Expressão Gênica/genética , Obesidade/genética , Adiponectina/análise , Adiponectina/sangue , Adulto , Antropometria , Índice de Massa Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Metilação de DNA/genética , Feminino , Genes fos/genética , Humanos , Resistência à Insulina/genética , Leptina/análise , Leptina/sangue , Masculino , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais/genética , Triglicerídeos/sangue
15.
Biomed Pharmacother ; 118: 109237, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31376653

RESUMO

Tea consumption has positive effects on the skeletal system and prevents postmenopausal osteoporosis, mainly by inhibiting osteoclastogenesis. In green tea, (-)-epigallocatechin-3-gallate (EGCG) is the most abundant and active compound and has been shown to inhibit RANKL-induced osteoclast formation. Taking into account the highly oxidizable and unstable nature of EGCG, we hypothesized that EGCG oxidation product exhibits greater anti-osteoclastogenesis potential than EGCG. In this study, we successfully isolated and identified an EGCG oxidation derivative, (-)-gallocatechin gallate (compound 2), using a chemical oxidation strategy. We then compared the ability of compound 2 and EGCG to inhibit RANKL-induced osteoclastogenesis in RAW 264.7 cells. The results of TRAP staining and F-actin ring immunofluorescent staining showed that compound 2 exhibits stronger inhibition of RANKL-induced osteoclast differentiation and F-actin ring formation, respectively, than EGCG. Additionally, quantitative real-time PCR (qRT-PCR) and western blotting analyses showed that compound 2 significantly and more strongly inhibited the expression of osteoclastogenesis-related marker genes and proteins, including c-Src, TRAP, cathepsin K, ß3-Integrin, and MMP-9, compared with EGCG. Furthermore, compound 2 significantly suppressed RANKL-induced expression of NFATc1 and c-Fos, the master transcriptional regulators of osteoclastogenesis, more strongly than EGCG. Mechanistically, molecular interaction assays showed that compound 2 binds to RANK with high affinity (KD = 189 nM) and blocks RANKL-RANK interactions, thereby suppressing RANKL-induced early RANK signaling pathways including p65, JNK, ERK, and p38 in osteoclast precursors. Taken together, this study demonstrates for the first time that an oxidation derivative of EGCG (compound 2) inhibits RANKL-induced osteoclastogenesis by suppressing RANK signaling pathways in RAW 264.7 cells.


Assuntos
Catequina/análogos & derivados , Osteogênese/efeitos dos fármacos , Ligante RANK/farmacologia , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Actinas/metabolismo , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Catequina/química , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Oxirredução , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Fator de Transcrição RelA/metabolismo
16.
Commun Biol ; 2: 292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396572

RESUMO

Receptor activator of nuclear factor (NF)-κB (RANK) signaling promotes pregnancy-dependent epithelial cell differentiation and expansion for mammary gland development, which requires NF-κB pathway-dependent Cyclin D1 induction and inhibitor of DNA binding 2 (Id2) pathway-dependent anti-apoptotic gene induction. However, the roles of tumor necrosis factor receptor-associated factor 6 (TRAF6) remain unclear despite its requirement in RANK signaling. Here we show that TRAF6 is crucial for both mammary stem cell maintenance and pregnancy-induced epithelial cell expansion. TRAF6 deficiency impairs phosphoinositide 3-kinase (PI3K)/AKT and canonical NF-κB pathways, whereas noncanonical NF-κB signaling remains functional. Therefore, we propose that TRAF6 promotes cell proliferation by activating PI3K/AKT signaling to induce retinoblastoma phosphorylation in concert with noncanonical NF-κB pathway-dependent Cyclin D1 induction. Furthermore, TRAF6 inhibits apoptosis by activating canonical NF-κB signaling to induce anti-apoptotic genes with the Id2 pathway. Therefore, proper orchestration of TRAF6-dependent and -independent RANK signals likely establishes mammary gland formation.


Assuntos
Proliferação de Células , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Células-Tronco/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/transplante , Animais , Apoptose , Linhagem Celular , Ciclina D1/metabolismo , Feminino , Glândulas Mamárias Animais/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Camundongos Knockout , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/deficiência , Fator 6 Associado a Receptor de TNF/genética
17.
Med Sci Monit ; 25: 5961-5968, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400110

RESUMO

BACKGROUND The aim of this study was to determine the effects of myeloma cells exposed to fluid shear stress on osteocytes and osteoclasts, and clarify the potential underlying mechanisms. MATERIAL AND METHODS A flow and a non-flow model were established using a flow fluid chamber. The myeloma cell line U266 and murine osteocytic MLO-Y4 cells were cultured in vitro. The osteocytes and osteoclasts were examined under a microscope. Osteoclasts were stained for tartrate-resistant acid phosphatase (TRAP) activity. RANKL and osteoprotegerin (OPG) gene expression were detected using reverse transcription-quantitative polymerase chain reaction. RESULTS Compared with the controls, Y4 cells cultured with U266 culture supernatant showed altered morphology, fewer osteocytes, increased RANKL gene expression, a higher RANKL/OPG gene ratio, and a greater number of TRAP-positive osteoclasts (P<0.05 for all). Compared to the no-flow model, the flow model showed a higher number of Y4 cells, increased OPG gene expression, decreased RANKL gene expression, a lower RANKL/OPG gene ratio, and fewer TRAP-positive osteoclasts (P<0.05 for all). CONCLUSIONS Our study revealed that fluid shear stress ameliorated the inhibitory effects of myeloma cells on osteocyte growth and inhibited osteoclast proliferation by means of decreasing RANKL/OPG gene expression. This may have clinical implications in patients with multiple myeloma in that mechanical loading with low-intensity vibration or mild exercise may prevent the progression of myeloma bone disease.


Assuntos
Mieloma Múltiplo/metabolismo , Osteoclastos/metabolismo , Osteócitos/metabolismo , Animais , Fenômenos Biomecânicos/fisiologia , Linhagem Celular Tumoral , Regulação da Expressão Gênica/genética , Humanos , Hidrodinâmica , Camundongos , Osteoprotegerina/metabolismo , Osteoprotegerina/fisiologia , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Estresse Mecânico , Microambiente Tumoral/fisiologia
18.
J Biol Regul Homeost Agents ; 33(4): 1105-1111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31332987

RESUMO

The adapter protein myeloid differentiation primary response gene 88 (MyD88) links the intracellular domains of interleukin receptors 1 and 18, and most Toll-like receptors (TLRs) to interleukin 1 receptor associated kinase (IRAK) signaling and subsequent NF-κB-mediated transcription. Previous work showed that mice with global deficiency of MyD88 (MyD88-/-) have osteopenic cancellous bone along with a reduction in osteoblastic but also osteoclastic surfaces. To further elucidate the role of MyD88 in bone, we utilized mice with osteoclast-restricted MyD88 expression in bone (MyD88OC). Bones of MyD88OC and wild type (wt) mice were examined by microCT analysis. Mechanical properties of bones were tested by three-point bending, and gene expression measured using quantitative real-time polymerase chain reaction. In MyD88OC mice, no osteopenic traits were observed, however, a drastic reduction in geometric parameters was detected. In trabecular bone a loss of connectivity density (-44%, p less than 0.0001) was measured and in cortical bone Imax (-31%, p less than 0.0001), Imin (-20%, p less than 0.001), J (-26%, p less than 0.0001) were reduced. Mechanical testing showed increased load to failure (77%, p less than 0.01) and decreased deflection at failure (-68%, p less than 0.01) of the femur. On the molecular level, relative gene expression analysis showed a (-29%, p less than 0.01) reduction in receptor activator of nuclear factor κ B ligand (RANKL) and no difference in osteoprotegerin (OPG) or RANK. Further, the bone resorption markers cathepsin K (CTSK) and tartrate-resistant acid phosphatase 5 (TRAP) were unchanged. In contrast, the bone formation markers collagen type 1 (COL1A1) and osteocalcin (OC) were decreased by -72% (p less than 0.0001) and -82% (p less than 0.0001), respectively. Together, our data suggests that the function of MyD88 in osteoclasts is sufficient to maintain bone mass, while it fails to preserve bone geometry, likely through dysfunctions in osteoblasts.


Assuntos
Reabsorção Óssea , Osso e Ossos/patologia , Fator 88 de Diferenciação Mieloide/metabolismo , Osteoclastos/citologia , Animais , Catepsina K/metabolismo , Diferenciação Celular , Colágeno Tipo I/metabolismo , Camundongos , Osteoblastos , Osteocalcina/metabolismo , Osteoclastos/metabolismo , Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Fosfatase Ácida Resistente a Tartarato/metabolismo
19.
Pathol Res Pract ; 215(9): 152517, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31262577

RESUMO

The role of RANKL/RANK/OPG system on bone remodeling is well known, and there is evidence that it is also important to cardiovascular and kidney pathology, although the underlying mechanisms are not elucidated so far. Thus, we investigated in a mice model of diet-induced obesity and diabetes if renal histopathological changes are associated with the expression of RANKL/RANK/OPG system and matrix metalloproteinases (MMPs). Three months old C57BL/6 mice were fed with control (C) AIN93 M diet or high-fat high sucrose (HFHS) diets for 21 weeks (CEUA/UFF #647/15). The two groups presented weight gain, but it was higher in the HFHS group compared to the C group (+35%, P = 0.0001). The HFHS group also had increased epididymal, inguinal and retroperitoneal fat pad weight (+121%, P = 0.0006; +287%, P = 0.0007 and; +286%, P < 0.0001, respectively), and hyperglycemia (+43%, P = 0.02). The kidney of some HFHS fed mice displayed mononuclear inflammatory cell infiltrate (40%), perivascular fibrosis (20%), and focal tubule mineralization (20%). Glomeruli hypertrophy was not detected. Unexpectedly, OPG, RANK, MMP-2, and MMP-9 expression was not altered in HFHS groups (Western blot analysis). In conclusion, the expression of RANKL/RANK/OPG system proteins and MMPs was not influenced by diet-induced obesity and diabetes in the kidney of male C57BL/6 mice, although some adverse histopathological remodeling is noticed in the renal tissue.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Rim/patologia , Metaloproteinases da Matriz/metabolismo , Obesidade/metabolismo , Osteoprotegerina/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Animais , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/patologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/patologia , Ligante RANK/metabolismo
20.
Int J Mol Sci ; 20(12)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216684

RESUMO

Acteoside, an active phenylethanoid glycoside compound isolated from herbs of Cistanche, was chosen for the investigation of anti-osteoporotic effect on postmenopausal osteoporosis by using an ovariectomized (OVX) mice model. The results from in vivo experiments showed that after daily oral administration of acteoside (20, 40, and 80 mg/kg body weight/day) for 12 weeks, bone mineral density and bone biomechanical properties of OVX mice were greatly enhanced, with significant improvement in bone microarchitecture. Furthermore, biochemical parameters of bone resorption markers as well as bone formation index, including tartrate-resistant acid phosphatase, cathepsin K, deoxypyridinoline, alkaline phosphatase, and bone gla-protein, were ameliorated by acteoside treatment, whereas the body, uterus, and vagina wet weights were seemingly not impacted by acteoside administration. Acteoside significantly affected osteoclastogenesis by attenuating nuclear factor kappa B (NF-κB) and stimulating phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signal pathways through down-regulated levels of tumor-necrosis factor receptor-associated factor 6 (TRAF6), receptor activator of nuclear factor kappa B ligand (RANKL), RANK, NFKBIA, IκB kinase ß, nuclear factor of activated T-cells c2 (NFAT2), and up-regulated expressions of PI3K, AKT, and c-Fos. Accordingly, the current research validated our hypothesis that acteoside possesses potent anti-osteoporotic properties and may be a promising agent for the prevention of osteoporosis in the future.


Assuntos
Glucosídeos/farmacologia , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia/efeitos adversos , Fenóis/farmacologia , Substâncias Protetoras/farmacologia , Animais , Biomarcadores , Peso Corporal , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/genética , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Modelos Animais de Doenças , Feminino , Camundongos , Modelos Biológicos , Tamanho do Órgão , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA