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1.
Nature ; 579(7797): 111-117, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103177

RESUMO

The avascular nature of cartilage makes it a unique tissue1-4, but whether and how the absence of nutrient supply regulates chondrogenesis remain unknown. Here we show that obstruction of vascular invasion during bone healing favours chondrogenic over osteogenic differentiation of skeletal progenitor cells. Unexpectedly, this process is driven by a decreased availability of extracellular lipids. When lipids are scarce, skeletal progenitors activate forkhead box O (FOXO) transcription factors, which bind to the Sox9 promoter and increase its expression. Besides initiating chondrogenesis, SOX9 acts as a regulator of cellular metabolism by suppressing oxidation of fatty acids, and thus adapts the cells to an avascular life. Our results define lipid scarcity as an important determinant of chondrogenic commitment, reveal a role for FOXO transcription factors during lipid starvation, and identify SOX9 as a critical metabolic mediator. These data highlight the importance of the nutritional microenvironment in the specification of skeletal cell fate.


Assuntos
Osso e Ossos/citologia , Microambiente Celular , Condrogênese , Metabolismo dos Lipídeos , Fatores de Transcrição SOX9/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Osso e Ossos/irrigação sanguínea , Condrócitos/citologia , Condrócitos/metabolismo , Ácidos Graxos/metabolismo , Feminino , Privação de Alimentos , Fatores de Transcrição Forkhead/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese , Oxirredução , Fatores de Transcrição SOX9/genética , Transdução de Sinais , Cicatrização
2.
J Transl Med ; 18(1): 43, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996227

RESUMO

BACKGROUND: There are several effective therapies for osteoporosis but these agents might cause serious adverse events. Lycopene intake could prevent bone loss, however studies on its effects on bone are scarce. Our aim was to investigate the effects of lycopene on osteoblast cells as well as bone mineral density and bone turnover markers in postmenopausal women. METHODS: We investigated the effect of lycopene on the Wnt/ß-catenin and ERK 1/2 pathways, RUNX2, alkaline phosphatase, RANKL and COL1A of Saos-2. We also carried out a pilot controlled clinical study to verify the feasibility of an approach for bone loss prevention through the intake of a lycopene-rich tomato sauce in 39 postmenopausal women. RESULTS: Lycopene 10 µM resulted in higher ß-catenin and phERK1/2 protein Vs the vehicle (p = 0.04 and p = 0.006). RUNX2 and COL1A mRNA was induced by both 5 and 10 µM doses (p = 0.03; p = 0.03 and p = 0.03; p = 0.05) while RANKL mRNA was reduced (p < 0.05). A significant bone density loss was not detected in women taking the tomato sauce while the control group had bone loss (p = 0.002). Tomato sauce intake resulted in a greater bone alkaline phosphatase reduction than the control (18% vs 8.5%, p = 0.03). CONCLUSIONS: Lycopene activates the WNT/ß-catenin and ERK1/2 pathways, upregulates RUNX2, alkaline phosphatase, COL1A and downregulates RANKL Saos-2. These processes contributed to prevent bone loss in postmenopausal women.


Assuntos
Osso e Ossos/efeitos dos fármacos , Licopeno/farmacologia , Osteoblastos/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Osteoblastos/citologia , Osteoblastos/metabolismo , Projetos Piloto , Estudos Prospectivos , RNA Mensageiro/genética , Via de Sinalização Wnt/efeitos dos fármacos
3.
Mater Sci Eng C Mater Biol Appl ; 107: 110301, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761156

RESUMO

Bone defects are a common clinical situation. However, bone regeneration remains a challenge and faces the limitation of poor engraftment due to deficient vascularisation. Poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHB-HV) and human adipose stem cells (hASC) are promising for vascularisation and bone regeneration. Therefore, we sought to investigate the bone regenerative capacity of hASCs cultured in allogeneic human serum (aHS) and PHB-HV scaffolds in a nude mouse model of the critical-sized calvarial defect. We evaluated bone healing for three treatment groups: empty (control), PHB-HV and PHB-HV + hASCs. The pre-implant analysis showed that hASCs colonised the PHB-HV scaffolds maintaining cell viability before implantation. Histological analysis revealed that PHB-HV scaffolds were tolerated in vivo; they integrated with adjacent tissue eliciting a response like a foreign body reaction, and tiny primary bone was observed only in the PHB-HV group. Also, the µ-CT analysis revealed only approximately 10% of new bone in the bone defect area in both the PHB-HV and PHB-HV + hASCs groups. The expression of BGLAP and its protein (osteocalcin) by PHB-HV + hASCs group and native bone was similar while the other bone markers RUNX2, ALPL and COL1A1 were upregulated, but this expression remained significantly lower compared to the native bone. Nevertheless, the PHB-HV group showed neovascularisation at 12 weeks post-implantation while PHB-HV + hASCs group also exhibited higher VEGFA expression as well as a higher number of vessels at 4 weeks post-implantation, and, consequently, earlier neovascularisation. This neovascularisation must be due to scaffold architecture, improved by hASCs, that survived for the long term in vivo in the PHB-HV + hASCs group. These results demonstrated that hASCs cultured in aHS combined with PHB-HV scaffolds were ineffective to promote bone regeneration, although the construct of hASCs + PHB-HV in xeno-free conditions improved scaffold vascularisation representing a strategy potentially promising for other tissue engineering applications.


Assuntos
Tecido Adiposo/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poliésteres , Engenharia Tecidual/métodos , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Osso e Ossos/irrigação sanguínea , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteocalcina/metabolismo , Poliésteres/química , Poliésteres/farmacologia , Tecidos Suporte
4.
Carbohydr Polym ; 229: 115514, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826429

RESUMO

This review focuses on recently developed alginate injectable hydrogels and alginate composites for applications in bone tissue regeneration, and it evaluates the alternatives to overcome the problems that avoid their utilization in the field. Section 2 covers the properties of alginates that have made them useful for medical applications, in particular their ionic gelling ability for preparing injectable compositions used as delivery drugs systems. The advantages and shortcomings of these preparations are revised together with the chemical modifications assayed. Section 3 describes how it has been taken advantage of alginates into the new field of biofabrication and the developments in bone engineering. The state of the art of this field is reviewed. Finally in Section 4, new developments and approaches that in opinion of the authors can lead to a breakthrough in bone tissue engineering using alginates are introduced.


Assuntos
Alginatos/química , Bioimpressão , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Engenharia Tecidual/métodos , Animais , Humanos , Injeções
5.
Int J Mol Sci ; 20(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623264

RESUMO

Multifunctional nanofibrous scaffolds for effective bone tissue engineering (BTE) application must incorporate factors to promote neovascularization and tissue regeneration. In this study, silica-coated gold nanoparticles Au(SiO2) were tested for their ability to promote differentiation of human mesenchymal stem cells (hMSCs) into osteoblasts. Biocompatible poly-ε-caprolactone (PCL), PCL/silk fibroin (SF) and PCL/SF/Au(SiO2) loaded nanofibrous scaffolds were first fabricated by an electrospinning method. Electrospun nanofibrous scaffolds were characterized for fiber architecture, porosity, pore size distribution, fiber wettability and the relevant mechanical properties using field emission scanning electron microscopy (FESEM), porosimetry, determination of water contact angle, measurements by a surface analyzer and tabletop tensile-tester measurements. FESEM images of the scaffolds revealed beadless, porous, uniform fibers with diameters in the range of 164 ± 18.65 nm to 215 ± 32.12 nm and porosity of around 88-92% and pore size distribution around 1.45-2.35 µm. Following hMSCs were cultured on the composite scaffolds. Cell-scaffold interaction, morphology and proliferation of were analyzed by FESEM analysis, MTS (3-(4,5-dimethyl thiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt) and CMFDA (5-choromethyl fluorescein acetate) dye assays. Osteogenic differentiation of MSCs into osteogenic cells were determined by alkaline phosphatase (ALP) activity, mineralization by alizarin red S (ARS) staining and osteocalcin expression by immunofluorescence staining. The results revealed that the addition of SF and Au(SiO2) to PCL scaffolds enhanced the mechanical strength, interconnecting porous structure and surface roughness of the scaffolds. This, in turn, led to successful osteogenic differentiation of hMSCs with improved cell adhesion, proliferation, differentiation, mineralization and expression of pro-osteogenic cellular proteins. This provides huge support for Au(SiO2) as a suitable material in BTE.


Assuntos
Osso e Ossos/citologia , Células-Tronco Mesenquimais/citologia , Nanopartículas Metálicas , Osteogênese , Dióxido de Silício , Engenharia Tecidual , Tecidos Suporte , Biomarcadores , Regeneração Óssea , Osso e Ossos/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis , Imunofluorescência , Ouro , Humanos , Imuno-Histoquímica , Nanopartículas Metálicas/ultraestrutura
6.
Int J Mol Sci ; 20(20)2019 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-31614903

RESUMO

The main goal of bone tissue engineering (BTE) is to refine and repair major bone defects based on bioactive biomaterials with distinct properties that can induce and support bone tissue formation. Graphene and its derivatives, such as graphene oxide (GO), display optimal properties for BTE, being able to support cell growth and proliferation, cell attachment, and cytoskeleton development as well as the activation of osteogenesis and bone development pathways. Conversely, the presence of GO within a polymer matrix produces favorable changes to scaffold morphologies that facilitate cell attachment and migration i.e., more ordered morphologies, greater surface area, and higher total porosity. Therefore, there is a need to explore the potential of GO for tissue engineering applications and regenerative medicine. Here, we aim to promote one novel scaffold based on a natural compound of chitosan, improved with 3 wt.% GO, for BTE approaches, considering its good biocompatibility, remarkable 3D characteristics, and ability to support stem cell differentiation processes towards the bone lineage.


Assuntos
Osso e Ossos/citologia , Quitosana/química , Grafite/química , Osteogênese , Engenharia Tecidual/métodos , Tecidos Suporte , Células-Tronco Adultas/citologia , Materiais Biocompatíveis/química , Regeneração Óssea , Osso e Ossos/ultraestrutura , Diferenciação Celular , Proliferação de Células , Humanos , Teste de Materiais , Conformação Molecular , Osteócitos/citologia , Osteócitos/ultraestrutura , Porosidade
7.
Elife ; 82019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588901

RESUMO

Mechanical loading, such as caused by exercise, stimulates bone formation by osteoblasts and increases bone strength, but the mechanisms are poorly understood. Osteocytes reside in bone matrix, sense changes in mechanical load, and produce signals that alter bone formation by osteoblasts. We report that the ion channel Piezo1 is required for changes in gene expression induced by fluid shear stress in cultured osteocytes and stimulation of Piezo1 by a small molecule agonist is sufficient to replicate the effects of fluid flow on osteocytes. Conditional deletion of Piezo1 in osteoblasts and osteocytes notably reduced bone mass and strength in mice. Conversely, administration of a Piezo1 agonist to adult mice increased bone mass, mimicking the effects of mechanical loading. These results demonstrate that Piezo1 is a mechanosensitive ion channel by which osteoblast lineage cells sense and respond to changes in mechanical load and identify a novel target for anabolic bone therapy.


Assuntos
Osso e Ossos/citologia , Osso e Ossos/fisiologia , Canais Iônicos/metabolismo , Osteócitos/metabolismo , Osteogênese , Estresse Mecânico , Animais , Linhagem Celular , Técnicas de Silenciamento de Genes , Canais Iônicos/administração & dosagem , Canais Iônicos/agonistas , Camundongos
8.
Mater Sci Eng C Mater Biol Appl ; 105: 110054, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546401

RESUMO

The construction of ceramic components with UV curing is a developing trend by an additive manufacturing (AM) technology, due to the excellent advantages of high precision selective fixation and rapid prototyping, the application of this technology to bone defect repair had become one of the hotspots of research. Hydroxyapatite (HAP) is one of the most popular calcium phosphate biomaterials, which is very close to the main ingredient of human bones. Thus, hydroxyapatite biomaterials are popular as bone graft materials. In summary, the preparation of HAP bioceramics by a 3D printing of digital light processing (DLP) is a promising work. However, the preparation of HAP hybrid suspensions with high solid loading and good fluidity that can be printed by DLP encountered some challenges. Therefore, the purpose of this work is to improve and develop a novel UV-curing suspension with a high solids loading, which the suspension with the hydrodynamic properties and stability are suitable for DLP printer, in order to compensate for the brittleness of HAP ceramics itself to a certain extent, a low amount of zirconia was added in the suspension as an additive to fabricate a zirconia toughened HAP bioceramic composite by a DLP of 3D printing. In this work, the HAP powder was pre-modified by two organic modifiers to improve the compatibility in the acrylic resin system, and the addition of the castor oil phosphate further reduced the shear stress of the suspension to ensure strong liquidity. The UV suspension with 60 wt% powder particle loading had a minimum viscosity of 7495 mPa·s at 30 rpm, which was vacuum sintered at 1100 °C, 1200 °C, and 1250 °C, respectively. The composite ceramics (with 6 wt% ZrO2) at 1200 °C had a relative density of 90.7%, while the sintered samples at 1250 °C had stronger tensile strength and bending strength. The toughening effect of zirconia incorporation on HAP ceramics was also confirmed by the change of tensile modulus and bending modulus, whereas the corresponding mechanical properties were also significantly enhanced.


Assuntos
Células da Medula Óssea/metabolismo , Osso e Ossos/metabolismo , Durapatita/química , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Impressão Tridimensional , Engenharia Tecidual , Zircônio/química , Animais , Células da Medula Óssea/citologia , Substitutos Ósseos/química , Osso e Ossos/citologia , Células-Tronco Mesenquimais/citologia , Camundongos
9.
Carbohydr Polym ; 224: 115176, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472871

RESUMO

Weak mechanical properties, lack biocompatibility and relatively bioinert are formidable obstruct in application of bone repair materials. Multifunctional composite materials have been considered as a viable solution to this problem. Here, a new double network (DN) hydrogel was constructed by physical cross-linking of medical grade poly (vinyl alcohol) (PVA) and chitosan in KOH/urea dissolution system. The obtained hydrogel demonstrated excellent tensile strength (0.24 MPa), elongation at break (286%), and high compressive strength (0.11 MPa on the strain of 60%). Our studies showed that the prepared hydrogel had excellent biocompatibility in vitro and the introduction of hydroxyapatite (HAp) by surface mineralization imparted hydrogel the ability to induce rat bone marrow stem cells (rBMSCs) differentiation. The in vivo experiments revealed that the surface mineralized double network hydrogel significantly accelerated simultaneous regeneration of bone defects in a rabbit bone defect model. All the results indicated that this hydrogel has the potential as a bone repair material.


Assuntos
Osso e Ossos/efeitos dos fármacos , Quitosana/química , Hidrogéis/química , Hidrogéis/farmacologia , Minerais/química , Álcool de Polivinil/química , Adsorção , Animais , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Força Compressiva , Hidróxidos/química , Osteogênese/efeitos dos fármacos , Compostos de Potássio/química , Coelhos , Soroalbumina Bovina/química , Propriedades de Superfície , Resistência à Tração , Engenharia Tecidual , Ureia/química
10.
Proc Inst Mech Eng H ; 233(11): 1165-1174, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31545134

RESUMO

This study aimed to produce a composite of poly(propylene fumarate)/magnesium calcium phosphate as a substitutional implant in the treatment of trabecular bone defects. So, the effect of magnesium calcium phosphate particle size, magnesium calcium phosphate:poly(propylene fumarate) weight ratio on compressive strength, Young's modulus, and toughness was assessed by considering effective fracture mechanisms. Micro-sized (∼30 µm) and nano-sized (∼50 nm) magnesium calcium phosphate particles were synthesized via emulsion precipitation and planetary milling methods, respectively, and added to poly(propylene fumarate) up to 20 wt.%. Compressive strength, Young's modulus, and toughness of the composites were measured by compressive test, and effective fracture mechanisms were evaluated by imaging fracture surface. In both micro- and nano-composites, the highest compressive strength was obtained by adding 10 wt.% magnesium calcium phosphate particles, and the enhancement in nano-composite was superior to micro-one. The micrographs of fracture surface revealed different mechanisms such as crack pinning, void plastic growth, and particle cleavage. According to the results, the produced composite can be considered as a candidate for substituting hard tissue.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Osso e Ossos/efeitos dos fármacos , Fumaratos/química , Fenômenos Mecânicos , Fosfatos/química , Polipropilenos/química , Osso e Ossos/citologia , Força Compressiva , Injeções , Teste de Materiais , Relação Estrutura-Atividade
11.
J Mater Sci Mater Med ; 30(8): 96, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31414231

RESUMO

Critical size bone defects that do not heal spontaneously are among the major reasons for the disability in majority of people with locomotor disabilities. Tissue engineering has become a promising approach for repairing such large tissue injuries including critical size bone defects. Three-dimension (3D) porous scaffolds based on piezoelectric polymers like poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) have received a lot of attention in bone tissue engineering due to their favorable osteogenic properties. Owing to the favourable redox properties, titanium dioxide (TiO2) nanostructures have gained a great deal of attention in bone tissue engineering. In this paper, tissue engineering scaffolds based on P(VDF-TrFE) loaded with TiO2 nanowires (TNW) were developed and evaluated for bone tissue engineering. Wet-chemical method was used for the synthesis of TNW. Obtained TNW were thoroughly characterized for the physicochemical and morphological properties using techniques such as X-Ray diffraction (XRD) analysis and transmission electron microscopy (TEM). Electrospinning was used to produce TNW incorporated P(VDF-TrFE) scaffolds. Developed scaffolds were characterized by state of art techniques such as Scanning Electron Microscopy (SEM), XRD and Differential scanning calorimetry (DSC) analyses. TEM analysis revealed that the obtained TiO2 nanostructures possess nanofibrous morphology with an average diameter of 26 ± 4 nm. Results of characterization of nanocomposite scaffolds confirmed the effective loading of TNW in P(VDF-TrFE) matrix. Fabricated P(VDF-TrFE)/TNW scaffolds possessed good mechanical strength and cytocompatibility. Osteoblast like cells showed higher adhesion and proliferation on the nanocomposite scaffolds. This investigation revealed that the developed P(VDF-TrFE) scaffolds containing TNW can be used as potential scaffolds for bone tissue engineering applications.


Assuntos
Osso e Ossos/citologia , Nanofios/química , Polivinil/química , Engenharia Tecidual , Tecidos Suporte/química , Titânio/química , Compostos de Vinila/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Hidrocarbonetos Fluorados/química , Teste de Materiais , Camundongos , Nanocompostos/química , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Ratos , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
12.
PLoS One ; 14(8): e0218230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31449527

RESUMO

Atonal homolog 8 (Atoh8) is a transcription factor of the basic helix-loop-helix (bHLH) protein family, which is expressed in the cartilaginous elements of endochondral bones. To analyze its function during chondrogenesis we deleted Atoh8 in mice using a chondrocyte- (Atoh8flox/flox;Col2a1-Cre) and a germline- (Atoh8flox/flox;Prx1-Crefemale) specific Cre allele. In both strains, Atoh8 deletion leads to a reduced skeletal size of the axial and appendicular bones, but the stages of phenotypic manifestations differ. While we observed obviously shortened bones in Atoh8flox/flox;Col2a1-Cre mice only postnatally, the bones of Atoh8flox/flox;Prx1-Crefemale mice are characterized by a reduced bone length already at prenatal stages. Detailed histological and molecular investigations revealed reduced zones of proliferating and hypertrophic chondrocytes. In addition, Atoh8 deletion identified Atoh8 as a positive regulator of chondrocyte proliferation. As increased Atoh8 expression is found in the region of prehypertrophic chondrocytes where the expression of Ihh, a main regulator of chondrocyte proliferation and differentiation, is induced, we investigated a potential interaction of Atoh8 function and Ihh signaling. By activating Ihh signaling with Purmorphamine we demonstrate that Atoh8 regulates chondrocyte proliferation in parallel or downstream of Ihh signaling while it acts on the onset of hypertrophy upstream of Ihh likely by modulating Ihh expression levels.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Osso e Ossos/citologia , Diferenciação Celular , Condrócitos/citologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Proliferação de Células , Condrócitos/patologia , Deleção de Genes , Regulação da Expressão Gênica , Proteínas Hedgehog/metabolismo , Hipertrofia , Masculino , Camundongos , Transporte Proteico , Transdução de Sinais
13.
Int Immunopharmacol ; 75: 105826, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31437791

RESUMO

Bone homeostasis requires a dynamic balance between osteogenesis and osteoclastogenesis, and osteolytic disorders are mainly attributed to aberrant osteoclastogenesis and bone resorption. Accumulating evidence has demonstrated that cyclin-dependent kinase 9 (CDK9) regulates some inflammatory diseases without affecting the cell cycle. Whether the specific inhibitor of CDK9, LDC000067 (abbreviated as LDC067), helps to prevent from osteolytic disorders has not been fully elucidated. Interestingly, this study demonstrated that LDC067 inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and bone resorption in vitro, and suppressed the expression of osteoclast-related marker genes such as cathepsin K (CTSK), tartrate-resistant acid phosphatase (TRAP), dendrite cell-specific transmembrane protein (DC-STAMP), V-ATPase D2, calcitonin receptor (CTR) and nuclear factor of activated T cells cytoplasmic 1 (NFATc1). The bone protective effects of LDC067 can be partly explained by its suppression of nuclear factor-kappa B (NF-κB)-mediated NFATc1 activation via AKT signalling pathway. In keeping with the results obtained in vitro, inhibition of CDK9 with LDC067 was observed to delay subchondral osteolysis and substantially ameliorate LPS-induced osteolysis in murine calvaria. Collectively, these results highlight the positive effects of LDC067 in preventing osteolytic disorders and indicate that this CDK9 inhibitor may a promising therapeutic agent.


Assuntos
Reabsorção Óssea/prevenção & controle , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Reabsorção Óssea/induzido quimicamente , Osso e Ossos/citologia , Bovinos , Células Cultivadas , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos Endogâmicos C57BL , Osteoclastos/fisiologia , Ligante RANK
14.
Int J Mol Sci ; 20(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438530

RESUMO

The availability of osteoinductive biomaterials has encouraged new therapies in bone regeneration and has potentially triggered paradigmatic shifts in the development of new implants in orthopedics and dentistry. Among several available synthetic biomaterials, bioceramics have gained attention for their ability to induce mesenchymal cell differentiation and successive bone formation when implanted in the human body. However, there is currently a lack of understanding regarding the fundamental biochemical mechanisms by which these materials can induce bone formation. Phenomenological studies of retrievals have clarified the final effect of bone formation, but have left the chemical interactions at the cell-material interface uncharted. Accordingly, the knowledge of the intrinsic material properties relevant for osteoblastogenesis and osteoinduction remains incomplete. Here, we systematically monitored in vitro the chemistry of mesenchymal cell metabolism and the ionic exchanges during osteoblastogenesis on selected substrates through conventional biological assays as well as via in situ and ex situ spectroscopic techniques. Accordingly, the chemical behavior of different bioceramic substrates during their interactions with mesenchymal cells could be unfolded and compared with that of biomedical titanium alloy. Our goal was to clarify the cascade of chemical equations behind the biological processes that govern osteoblastogenic effects on different biomaterial substrates.


Assuntos
Materiais Biocompatíveis/química , Titânio/química , Regeneração Óssea/fisiologia , Osso e Ossos/citologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Análise Espectral Raman
15.
J Recept Signal Transduct Res ; 39(3): 199-207, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31466503

RESUMO

Context: Bone mesenchymal stem cells (BMSC)-based regenerative therapy is critical for the craniofacial defect reconstruction. However, oxidative stress micro-environment after transplantation limits the therapeutic efficiency of BMSC. The miR-181c has been found to be associated with cell survival and proliferation. Objective: Herein, we investigated whether prior miR-181c treatment promoted BMSC proliferation and survival under oxidative stress injury. Materials and methods: Cells were treated with hydrogen peroxide (H2O2) and then cell viability was determined via MTT assay, TUNEL staining and ELISA. Western blotting and immunofluorescence assay were used to detect those alterations of mitochondrial function. Results: H2O2 treatment reduced BMSC viability and this effect could be reversed via additional supplementation of miR181-c. Mechanistically, oxidative stress increased cell apoptosis, augmented caspase-3 activity, promoted reactive oxygen species (ROS) synthesis, impaired mitochondrial potential, and induced mitochondrial dynamics imbalance. However, miR-181c pretreatment reversed these effects of oxidative stress on BMSC. Moreover, miR-181c treatment improved BMSC proliferation, migration and paracrine, which are very important for craniofacial reconstruction. In addition, we identified that AMPK-Mfn1 axis was the direct targets of miR-181c in BMSC. Mfn1 silencing impaired the protective effects miR-181c on BMSC viability and proliferation under oxidative stress environment. Conclusions: Collectively, our results indicate that miR-181c participates in oxidative stress-mediated BMSC damage by modulating the AMPK-Mfn1 signaling pathway, suggesting miR-181c-AMPK-Mfn1 axis may serves as novel therapeutic targets to facilitate craniofacial defect reconstruction.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Osso e Ossos/citologia , Anormalidades Craniofaciais/patologia , Proteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Proteínas Mitocondriais/metabolismo , Transdução de Sinais , Animais , Apoptose , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Regulação para Baixo/genética , Metabolismo Energético , Peróxido de Hidrogênio/metabolismo , MicroRNAs/genética , Estresse Oxidativo , Ratos Sprague-Dawley
16.
Nat Commun ; 10(1): 3168, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31320650

RESUMO

Multipotent mesenchymal stromal cells (MSCs) are required for skeletal formation, maintenance, and repair throughout life; however, current models posit that postnatally arising long-lived adult MSCs replace transient embryonic progenitor populations. We previously reported exclusive expression and function of the embryonic patterning transcription factor, Hoxa11, in adult skeletal progenitor-enriched MSCs. Here, using a newly generated Hoxa11-CreERT2 lineage-tracing system, we show Hoxa11-lineage marked cells give rise to all skeletal lineages throughout the life of the animal and persist as MSCs. Hoxa11 lineage-positive cells give rise to previously described progenitor-enriched MSC populations marked by LepR-Cre and Osx-CreER, placing them upstream of these populations. Our studies establish that Hox-expressing cells are skeletal stem cells that arise from the earliest stages of skeletal development and self-renew throughout the life of the animal.


Assuntos
Adipócitos/citologia , Condrócitos/citologia , Proteínas de Homeodomínio/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Animais , Regeneração Óssea/genética , Osso e Ossos/citologia , Osso e Ossos/embriologia , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Animais , Receptores para Leptina/genética , Fator de Transcrição Sp7/genética
17.
Int J Biol Macromol ; 137: 1256-1267, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31279876

RESUMO

Past researches on bone regeneration field have shown the positive impacts of the presence of Zinc and Magnesium ions in the bioactive glasses composition. However, there is no dedicated work on the effect of the aforementioned bio-glass on the polymer matrix composites. The key idea of the approach is to improve antibacterial efficacy, biological activity and mechanical properties of the bone composite scaffolds by incorporating bioactive glasses containing Zinc and Magnesium into alginate networks. The prepared scaffolds were characterized by SEM, ATR-FTIR and XRD analysis. Compression strength of obtained highly porous composite scaffolds was remarkably enhanced by the presence of bio-glass particles. The maximum compressive strength (1.7 MPa) was obtained for alginate composite containing 1 g Mg-Zn-BG. In vitro evaluation such as swelling, bio-mineralization, biodegradation were carried out, which indicates that incorporation of bio-glass promotes apatite deposition on composite scaffolds. Cytotoxicity, cell attachment and proliferation and osteogenic differentiation were also evaluated by culturing MG-63 cells on scaffolds. ICP analysis were conducted after 60 days of incubation in PBS solution to verify the ion release capability of the composite scaffolds, particularly Zn and Mg ions, which resulted in significant antibacterial efficacy enhancement of composite scaffolds against E. coli and S. aureus bacteria.


Assuntos
Alginatos/química , Osso e Ossos/citologia , Vidro/química , Magnésio/química , Engenharia Tecidual , Tecidos Suporte/química , Zinco/química , Alginatos/farmacologia , Alginatos/toxicidade , Fosfatase Alcalina/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Calcificação Fisiológica/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Teste de Materiais , Fenômenos Mecânicos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Porosidade
18.
Mater Sci Eng C Mater Biol Appl ; 103: 109731, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349472

RESUMO

The fabrication of bone tissue engineering scaffolds with high osteogenic ability and favorable mechanical properties is of huge interest. In this study, a silk fibroin (SF) solution of 30 wt% was extracted from cocoons and combined with mesoporous bioactive glass (MBG) to fabricate MBG/SF composite scaffolds by 3D printing. The porosity, compressive strength, degradation and apatite forming ability were evaluated. The results illustrated that MBG/SF scaffolds had superior compressive strength (ca. 20 MPa) and good biocompatibility, and stimulated bone formation ability compared to mesoporous bioactive glass/polycaprolactone (MBG/PCL) scaffolds. We subcutaneously transplanted hBMSCs-loaded MBG/SF and MBG/PCL scaffolds into the back of nude mice to evaluate heterotopic bone formation assay in vivo, and the results revealed that the gene expression levels of common osteogenic biomarkers on MBG/SF scaffolds were significantly better than MBG/PCL scaffolds. These results showed that 3D-printed MBG/SF composite scaffolds are great promising for bone tissue engineering.


Assuntos
Células da Medula Óssea/metabolismo , Osso e Ossos/metabolismo , Fibroínas/química , Vidro/química , Impressão Tridimensional , Células-Tronco/metabolismo , Engenharia Tecidual , Tecidos Suporte/química , Células da Medula Óssea/citologia , Osso e Ossos/citologia , Humanos , Teste de Materiais , Poliésteres/química , Porosidade , Células-Tronco/citologia
19.
Nutrients ; 11(6)2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31159319

RESUMO

Collagen proteins are crucial components of the bone matrix. Since collagen-derived products are widely used in the food and supplement industry, one may raise the question whether collagen-enriched diets can provide benefits for the skeleton. In this study, we designed an innovative approach to investigate this question taking into account the metabolites that are formed by the digestive tract and appear in the circulation after ingestion of hydrolysed collagen. Blood samples collected in clinical and pre-clinical trials following ingestion and absorption of hydrolysed collagen were processed and applied on bone-related primary cell cultures. This original ex vivo methodology revealed that hydrolysed collagen-enriched serum had a direct impact on the behaviour of cells from both human and mouse origin that was not observed with controls (bovine serum albumin or hydrolysed casein-enriched serum). These ex vivo findings were fully in line with in vivo results obtained from a mouse model of post-menopausal osteoporosis. A significant reduction of bone loss was observed in mice supplemented with hydrolysed collagen compared to a control protein. Both the modulation of osteoblast and osteoclast activity observed upon incubation with human or mouse serum ex vivo and the attenuation of bone loss in vivo, clearly indicates that the benefits of hydrolysed collagen for osteoporosis prevention go beyond the effect of a simple protein supplementation.


Assuntos
Osso e Ossos/citologia , Colágeno/administração & dosagem , Células 3T3 , Animais , Densidade Óssea , Células da Medula Óssea , Proliferação de Células , Suplementos Nutricionais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidrólise , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Ovariectomia , Ligante RANK/genética , Ligante RANK/metabolismo , Células RAW 264.7 , Distribuição Aleatória
20.
Nat Commun ; 10(1): 2829, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249296

RESUMO

Extracellular vesicles (EVs) are involved in the regulation of cell physiological activity and the reconstruction of extracellular environment. Matrix vesicles (MVs) are a type of EVs released by bone-related functional cells, and they participate in the regulation of cell mineralization. Here, we report bioinspired MVs embedded with black phosphorus (BP) and functionalized with cell-specific aptamer (denoted as Apt-bioinspired MVs) for stimulating biomineralization. The aptamer can direct bioinspired MVs to targeted cells, and the increasing concentration of inorganic phosphate originating from BP can facilitate cell biomineralization. The photothermal effect of the Apt-bioinspired MVs can also promote the biomineralization process by stimulating the upregulated expression of heat shock proteins and alkaline phosphatase. In addition, the Apt-bioinspired MVs display outstanding bone regeneration performance. Our strategy provides a method for designing bionic tools to study the mechanisms of biological processes and advance the development of medical engineering.


Assuntos
Vesículas Extracelulares/metabolismo , Fósforo/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Biomineralização , Osso e Ossos/química , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Vesículas Extracelulares/química , Feminino , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/química , Osteoblastos/metabolismo , Fosfatos/metabolismo , Fósforo/química , Ratos
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