RESUMO
Chitosan is a promising natural polymer for coatings, it combines intrinsic antibacterial and pro-osteoblastic properties, but the literature still has a gap from the development to behavior of these coatings, so this systematic review aimed to answer, "What is the relationship between the physical and chemical properties of polymeric chitosan coatings on titanium implants on antibacterial activity and osteoblast viability?". PRISMA guidelines was followed, the search was applied into 4 databases and grey literature, without the restriction of time and language. The selection process occurred in 2 blinded steps by the authors. The criteria of eligibility were in vitro studies that evaluated the physical, chemical, microbiological, and biological properties of chitosan coatings on titanium surfaces. The risk of bias was analyzed by the specific tool. Of 734 potential articles 10 were included; all had low risk of bias. The coating was assessed according to the technique of fabrication, FT-IR, thickness, adhesion, roughness, wettability, antibacterial activity, and osteoblast viability. The analyzed coatings showed efficacy on antibacterial activity and cytocompatibility dependent on the class of material incorporated. Thus, this review motivates the development of time-dependent studies to optimize manufacturing and allow for an increase in patents and availability on the market.
Assuntos
Antibacterianos , Quitosana , Materiais Revestidos Biocompatíveis , Osteoblastos , Titânio , Quitosana/química , Quitosana/farmacologia , Titânio/química , Titânio/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Propriedades de Superfície , Próteses e Implantes , Animais , Sobrevivência Celular/efeitos dos fármacosRESUMO
Blood vessel growth and osteogenesis in the skeletal system are coupled; however, fundamental aspects of vascular function in osteoblast-to-osteocyte transition remain unclear. Our study demonstrates that vascular smooth muscle cells (VSMCs), but not endothelial cells, are sufficient to drive bone marrow mesenchymal stromal cell-derived osteoblast-to-osteocyte transition via ß-catenin signaling and exosome-mediated communication. We found that VSMC-derived exosomes are loaded with transcripts encoding proteins associated with the osteocyte phenotype and members of the WNT/ß-catenin signaling pathway. In contrast, endothelial cell-derived exosomes facilitated mature osteoblast differentiation by reprogramming the TGFB1 gene family and osteogenic transcription factors osterix (SP7) and RUNX2. Notably, VSMCs express significant levels of tetraspanins (CD9, CD63, and CD81) and drive the intracellular trafficking of exosomes with a lower membrane zeta potential than those from other cells. Additionally, the high ATP content within these exosomes supports mineralization mechanisms, as ATP is a substrate for alkaline phosphatase. Osteocyte function was further validated by RNA sequencing, revealing activity in genes related to intermittent mineralization and sonic hedgehog signaling, alongside a significant increase in TNFSF11 levels. Our findings unveil a novel role of VSMCs in promoting osteoblast-to-osteocyte transition, thus offering new insights into bone biology and homeostasis, as well as in bone-related diseases. Clinically, these insights could pave the way for innovative therapeutic strategies targeting VSMC-derived exosome pathways to treat bone-related disorders such as osteoporosis. By manipulating these signaling pathways, it may be possible to enhance bone regeneration and improve skeletal health in patients with compromised bone structure and function.
Assuntos
Exossomos , Músculo Liso Vascular , Osteoblastos , Osteócitos , Osteogênese , beta Catenina , Osteoblastos/metabolismo , Osteoblastos/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/citologia , Exossomos/metabolismo , Animais , beta Catenina/metabolismo , beta Catenina/genética , Osteócitos/metabolismo , Osteócitos/citologia , Camundongos , Osteogênese/genética , Osteogênese/fisiologia , Miócitos de Músculo Liso/metabolismo , Diferenciação Celular , Humanos , Via de Sinalização Wnt , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Células Cultivadas , Transdução de Sinais , Camundongos Endogâmicos C57BLRESUMO
This study delves into the potential of amorphous titanium oxide (aTiO2) nano-coating to enhance various critical aspects of non-Ti-based metallic orthopedic implants. These implants, such as medical-grade stainless steel (SS), are widely used for orthopedic devices that demand high strength and durability. The aTiO2nano-coating, deposited via magnetron sputtering, is a unique attempt to improve the osteogenesis, the inflammatory response, and to reduce bacterial colonization on SS substrates. The study characterized the nanocoated surfaces (SS-a TiO2) in topography, roughness, wettability, and chemical composition. Comparative samples included uncoated SS and sandblasted/acid-etched Ti substrates (Ti). The biological effects were assessed using human mesenchymal stem cells (MSCs) and primary murine macrophages. Bacterial tests were carried out with two aerobic pathogens (S. aureusandS. epidermidis) and an anaerobic bacterial consortium representing an oral dental biofilm. Results from this study provide strong evidence of the positive effects of the aTiO2nano-coating on SS surfaces. The coating enhanced MSC osteoblastic differentiation and exhibited a response similar to that observed on Ti surfaces. Macrophages cultured on aTiO2nano-coating and Ti surfaces showed comparable anti-inflammatory phenotypes. Most significantly, a reduction in bacterial colonization across tested species was observed compared to uncoated SS substrates, further supporting the potential of aTiO2nano-coating in biomedical applications. The findings underscore the potential of magnetron-sputtering deposition of aTiO2nano-coating on non-Ti metallic surfaces such as medical-grade SS as a viable strategy to enhance osteoinductive factors and decrease pathogenic bacterial adhesion. This could significantly improve the performance of metallic-based biomedical devices beyond titanium.
Assuntos
Materiais Revestidos Biocompatíveis , Macrófagos , Teste de Materiais , Células-Tronco Mesenquimais , Osteogênese , Aço Inoxidável , Propriedades de Superfície , Titânio , Titânio/química , Aço Inoxidável/química , Animais , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Macrófagos/metabolismo , Osteogênese/efeitos dos fármacos , Diferenciação Celular , Próteses e Implantes , Osteoblastos/citologia , Staphylococcus aureus/efeitos dos fármacos , Biofilmes , Staphylococcus epidermidis/efeitos dos fármacos , Aderência Bacteriana , MolhabilidadeRESUMO
Dental implant surface properties such as roughness, wettability, and porosity ensure cell interaction and tissue integration. The clinical performance of dental implants depends on the crystallographic texture and protein and cell bonds to the substrates, where grain size, orientation, and inclination are parameters responsible for favoring osteoblast adhesion and limiting bacterial adhesion. The lack of consensus on the best crystallographic plan for cell adhesion prompted this systematic review, which aims to answer the following question: "What is the influence of the crystallographic plane on titanium surfaces on cell adhesion?" by evaluating the literature on the crystallographic characteristics of titanium and how these dictate topographical parameters and influence the cell adhesion of devices made from this material. It followed the Preferred Reporting Standards for Systematic Reviews and Meta-Analyses (PRISMA 2020) registered with the Open Science Framework (OSF) (osf.io/xq6kv). The search strategy was based on the PICOS method. It chose in vitro articles that analyzed crystallographic structure correlated with cell adhesion and investigated the microstructure and its effects on cell culture, different crystal orientation distributions, and the influence of crystallinity. The search strategies were applied to the different electronic databases: PubMed, Scopus, Science Direct, Embase, and Google Scholar, and the articles found were attached to the Rayyan digital platform and assessed blindly. The Joanna Bringgs Institute (JBI) tool assessed the risk of bias. A total of 248 articles were found. After removing duplicates, 192 were analyzed by title and abstract. Of these, 18 were selected for detailed reading in their entirety, 9 of which met the eligibility criteria. The included studies presented a low risk of bias. The role of the crystallographic orientation of the exposed faces in a multicrystalline material is little discussed in the scientific literature and its impact is recognized as dictating the topographical characteristics of the material that facilitate cell adhesion.
Assuntos
Adesão Celular , Titânio , Titânio/química , Humanos , Propriedades de Superfície , Implantes Dentários , Cristalografia , Animais , Osteoblastos/metabolismo , Osteoblastos/citologiaRESUMO
Bioactive and biodegradable scaffolds that mimic the natural extracellular matrix of bone serve as temporary structures to guide new bone tissue growth. In this study, 3D-printed scaffolds composed of poly (lactic acid) (PLA)-tricalcium phosphate (TCP) (90-10 wt.%) were modified with 1%, 5%, and 10 wt.% of ZnO to enhance bone tissue regeneration. A commercial chain extender named Joncryl was incorporated alongside ZnO to ensure the printability of the composites. Filaments were manufactured using a twin-screw extruder and subsequently used to print 3D scaffolds via fused filament fabrication (FFF). The scaffolds exhibited a homogeneous distribution of ZnO and TCP particles, a reproducible structure with 300 µm pores, and mechanical properties suitable for bone tissue engineering, with an elastic modulus around 100 MPa. The addition of ZnO resulted in enhanced surface roughness on the scaffolds, particularly for ZnO microparticles, achieving values up to 241 nm. This rougher topography was responsible for enhancing protein adsorption on the scaffolds, with an increase of up to 85% compared to the PLA-TCP matrix. Biological analyses demonstrated that the presence of ZnO promotes mesenchymal stem cell (MSC) proliferation and differentiation into osteoblasts. Alkaline phosphatase (ALP) activity, an important indicator of early osteogenic differentiation, increased up to 29%. The PLA-TCP composite containing 5% ZnO microparticles exhibited an optimized degradation rate and enhanced bioactivity, indicating its promising potential for bone repair applications.
Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Fosfatos de Cálcio , Diferenciação Celular , Proliferação de Células , Células-Tronco Mesenquimais , Osteoblastos , Poliésteres , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Óxido de Zinco , Alicerces Teciduais/química , Fosfatos de Cálcio/química , Poliésteres/química , Regeneração Óssea/efeitos dos fármacos , Engenharia Tecidual/métodos , Células-Tronco Mesenquimais/citologia , Óxido de Zinco/química , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Osteoblastos/citologia , Osteogênese/efeitos dos fármacos , Teste de Materiais , Osso e Ossos , Regeneração Tecidual Guiada/métodos , Humanos , Animais , Fosfatase Alcalina/metabolismo , Módulo de Elasticidade , Porosidade , Propriedades de SuperfícieRESUMO
The present study aimed to evaluate the effect of photobiomodulation therapy (PBM) on different stages of osteogenesis in vitro. For this, osteoblastic-like cells (Saos-2 cell lineage) were irradiated in two different periods: during the Proliferation phase (PP; from the second to the fourth day) and during the Differentiation phase (DP; from the seventh to the ninth day). The energy density used in the study was 1.5 J/ cm2. The following parameters were evaluated: 1) quantification of collagen type 1 (COL 1), osteopontin (OPN), and bone morphogenetic protein 2 (BMP-2); 2) quantification of alkaline phosphatase (ALP) activity; and 3) quantification of extracellular matrix (ECM) mineralization. Non-irradiated cultures were used as controls. The data were analyzed using the Student's t-test or one-way ANOVA, considering a significance level of 5%. The results indicated that COL 1 and BMP-2 quantification was higher in Saos-2 irradiated during the DP in relation to the control group at day 10 (p < 0.05). No differences were observed for other comparisons at this time point (p > 0.05). OPN expression was greater in PP compared with the other experimental groups at day 10 (p < 0.05). Irradiation did not affect ALP activity in Saos-2 regardless of the exposure phase and the time point evaluated (p > 0.05). At day 14, ECM mineralization was higher in Saos-2 cultures irradiated during the DP in relation to the PP (p < 0.05). In conclusion, the results suggested that the effects of PBM on osteoblastic cells may be influenced by the stage of cell differentiation.
Assuntos
Fosfatase Alcalina , Proteína Morfogenética Óssea 2 , Diferenciação Celular , Proliferação de Células , Colágeno Tipo I , Terapia com Luz de Baixa Intensidade , Osteoblastos , Osteogênese , Osteopontina , Osteogênese/efeitos da radiação , Humanos , Proteína Morfogenética Óssea 2/metabolismo , Fosfatase Alcalina/metabolismo , Osteopontina/metabolismo , Diferenciação Celular/efeitos da radiação , Colágeno Tipo I/metabolismo , Osteoblastos/efeitos da radiação , Osteoblastos/citologia , Osteoblastos/metabolismo , Proliferação de Células/efeitos da radiação , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos da radiaçãoRESUMO
Insufficient osseointegration of titanium-based implants is a factor conditioning their long-term success. Therefore, different surface modifications, such as multifunctional oxide coatings, calcium phosphates, and the addition of molecules such as peptides, have been developed to improve the bioactivity of titanium-based biomaterials. In this work, we investigate the behavior of human oral mucosal stem cells (hOMSCs) cultured on amorphous titanium oxide (aTiO2), surfaces designed to simulate titanium (Ti) surfaces, biofunctionalized with a novel sequence derived from cementum attachment protein (CAP-p15), exploring its impact on guiding hOMSCs towards an osteogenic phenotype. We carried out cell attachment and viability assays. Next, hOMSCs differentiation was assessed by red alizarin stain, ALP activity, and western blot analysis by evaluating the expression of RUNX2, BSP, BMP2, and OCN at the protein level. Our results showed that functionalized surfaces with CAP-p15 (1 µg ml-1) displayed a synergistic effect increasing cell proliferation and cell attachment, ALP activity, and expression of osteogenic-related markers. These data demonstrate that CAP-p15 and its interaction with aTiO2surfaces promote osteoblastic differentiation and enhanced mineralization of hOMSCs when compared to pristine samples. Therefore, CAP-p15 shows the potential to be used as a therapeutical molecule capable of inducing mineralized tissue regeneration onto titanium-based implants.
Assuntos
Adesão Celular , Diferenciação Celular , Proliferação de Células , Mucosa Bucal , Osteogênese , Células-Tronco , Titânio , Titânio/química , Humanos , Osteogênese/efeitos dos fármacos , Mucosa Bucal/citologia , Mucosa Bucal/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Propriedades de Superfície , Células Cultivadas , Osteoblastos/citologia , Osteoblastos/metabolismo , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Sobrevivência Celular , Osseointegração/efeitos dos fármacos , Materiais Biocompatíveis/químicaRESUMO
Bone tissue regeneration strategies have incorporated the use of natural polymers, such as hydroxyapatite (nHA), chitosan (CH), gelatin (GEL), or alginate (ALG). Additionally, platelet concentrates, such as platelet-rich fibrin (PRF) have been suggested to improve scaffold biocompatibility. This study aimed to develop scaffolds composed of nHA, GEL, and CH, with or without ALG and lyophilized PRF, to evaluate the scaffold's properties, growth factor release, and dental pulp stem cells (DPSC), and osteoblast (OB) derived from DPSC viability. Four scaffold variations were synthesized and lyophilized. Then, degradation, swelling profiles, and morphological analysis were performed. Furthermore, PDGF-BB and FGF-B growth factors release were quantified by ELISA, and cytotoxicity and cell viability were evaluated. The swelling and degradation profiles were similar in all scaffolds, with pore sizes ranging between 100 and 250 µm. FGF-B and PDGF-BB release was evidenced after 24 h of scaffold immersion in cell culture medium. DPSC and OB-DPSC viability was notably increased in PRF-supplemented scaffolds. The nHA-CH-GEL-PRF scaffold demonstrated optimal physical-biological characteristics for stimulating DPSC and OB-DPSC cell viability. These results suggest lyophilized PRF improves scaffold biocompatibility for bone tissue regeneration purposes.
Assuntos
Alginatos , Sobrevivência Celular , Quitosana , Polpa Dentária , Durapatita , Gelatina , Osteoblastos , Fibrina Rica em Plaquetas , Células-Tronco , Alicerces Teciduais , Humanos , Polpa Dentária/citologia , Quitosana/química , Quitosana/farmacologia , Gelatina/química , Fibrina Rica em Plaquetas/química , Fibrina Rica em Plaquetas/metabolismo , Alicerces Teciduais/química , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Durapatita/química , Durapatita/farmacologia , Alginatos/química , Alginatos/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Adesão Celular/efeitos dos fármacos , Engenharia Tecidual/métodos , Células CultivadasRESUMO
Mechanical properties are becoming fundamental for advancing the comprehension of cellular processes. This study addresses the relationship between viscoelastic properties and the cellular mineralization process. Osteoblast-like cells treated with an osteogenic medium were employed for this purpose. Additionally, the study explores the impact of hydroxyapatite (HA) and hydroxyapatite/silver (HA/Ag) composite on this process. AFM relaxation experiments were conducted to extract viscoelastic parameters using the Fractional Zener (FZ) and Fractional Kelvin (FK) models. Our findings revealed that the main phases of mineralization are associated with alterations in the viscoelastic properties of osteoblast-like cells. Furthermore, HA and HA/Ag treatments significantly influenced changes in the viscoelastic properties of these cells. In particular, the HA/Ag treatment demonstrated a marked enhancement in cell fluidity, suggesting a possible role of silver in accelerating the mineralization process. Moreover, the study underscores the independence observed between fluidity and stiffness, indicating that modifications in one parameter may not necessarily correspond to changes in the other. These findings shed light on the factors involved in the cellular mineralization process and emphasize the importance of using viscoelastic properties to discern the impact of treatments on cells.
Assuntos
Calcificação Fisiológica , Durapatita , Elasticidade , Osteoblastos , Prata , Durapatita/química , Osteoblastos/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Prata/química , Calcificação Fisiológica/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Viscosidade , Linhagem Celular , Humanos , Microscopia de Força Atômica , AnimaisRESUMO
This work presents the effect of the silicocarnotite (SC) and nagelschmidtite (Nagel) phases on in vitro osteogenesis. The known hydroxyapatite of biological origin (BHAp) was used as a standard of osteoconductive characteristics. The evaluation was carried out in conventional and osteogenic media for comparative purposes to assess the osteogenic ability of the bioceramics. First, the effect of the material on cell viability at 24 h, 7 and 14 days of incubation was evaluated. In addition, cell morphology and attachment on dense bioceramic surfaces were observed by fluorescence microscopy. Specifically, alkaline phosphatase (ALP) activity was evaluated as an osteogenic marker of the early stages of bone cell differentiation. Mineralized extracellular matrix was observed by calcium phosphate deposits and extracellular vesicle formation. Furthermore, cell phenotype determination was confirmed by scanning electron microscope. The results provided relevant information on the cell attachment, proliferation, and osteogenic differentiation processes after 7 and 14 days of incubation. Finally, it was demonstrated that SC and Nagel phases promote cell proliferation and differentiation, while the Nagel phase exhibited a superior osteoconductive behavior and could promote MC3T3-E1 cell differentiation to a higher extent than SC and BHAp, which was reflected in a higher number of deposits in a shorter period for both conventional and osteogenic media.
Assuntos
Diferenciação Celular , Cerâmica , Durapatita , Osteoblastos , Osteogênese , Silicatos , Animais , Camundongos , Durapatita/química , Durapatita/farmacologia , Cerâmica/química , Cerâmica/farmacologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoblastos/efeitos dos fármacos , Silicatos/química , Silicatos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Biocompatíveis/química , Fosfatase Alcalina/metabolismo , Compostos de Cálcio/farmacologia , Compostos de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Células 3T3 , Linhagem CelularRESUMO
Estrogen deficiency, long-term immobilization, and/or aging are commonly related to bone mass loss, thus increasing the risk of fractures. One option for bone replacement in injuries caused by either traumas or pathologies is the use of orthopedic cement based on polymethylmethacrylate (PMMA). Nevertheless, its reduced bioactivity may induce long-term detachment from the host tissue, resulting in the failure of the implant. In view of this problem, we developed an alternative PMMA-based porous cement (pPMMA) that favors cell invasion and improves osteointegration with better biocompatibility. The cement composition was changed by adding bioactive strontium-nanoparticles that mimic the structure of bone apatite. The nanoparticles were characterized regarding their physical-chemical properties, and their effects on osteoblasts and osteoclast cultures were assessed. Initial in vivo tests were also performed using 16 New Zealand rabbits as animal models, in which the pPMMA-cement containing the strontium nanoparticles were implanted. We showed that the apatite nanoparticles in which 90% of Ca2+ ions were substituted by Sr2+ (NanoSr 90%) upregulated TNAP activity and increased matrix mineralization. Moreover, at the molecular level, NanoSr 90% upregulated the mRNA expression levels of, Sp7, and OCN. Runx2 was increased at both mRNA and protein levels. In parallel, in vivo tests revealed that pPMMA-cement containing NanoSr 90%, upregulated two markers of bone maturation, OCN and BMP2, as well as the formation of apatite minerals after implantation in the femur of rabbits. The overall data support that strontium nanoparticles hold the potential to up-regulate mineralization in osteoblasts when associated with synthetic biomaterials.
Assuntos
Osteoblastos , Estrôncio , Animais , Estrôncio/farmacologia , Estrôncio/química , Coelhos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/citologia , Nanopartículas/química , Polimetil Metacrilato/química , Polimetil Metacrilato/farmacologia , Cimentos Ósseos/farmacologia , Cimentos Ósseos/química , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , CamundongosRESUMO
MicroRNAs (miRNAs) are small non-coding RNA molecules that play critical roles in post-transcriptional gene regulation. They function by binding to target messenger RNA (mRNA) molecules, leading to their degradation or inhibiting their translation into proteins. In the context of skeletal diseases, such as osteoporosis, osteoarthritis, and bone metastasis, there is growing evidence osteoblastic miRNAs, are involved in the regulation of bone formation and maintenance.Osteoblasts are bone-forming cells responsible for synthesizing and depositing the extracellular matrix, which ultimately mineralizes to form bone tissue. Osteoblastic miRNAs modulate various aspects of osteoblast function, including proliferation, differentiation, mineralization, and apoptosis. Dysregulation of these miRNAs can disrupt the balance between bone formation and resorption, leading to skeletal diseases.The therapeutic implications of targeting osteoblastic miRNAs in skeletal diseases are significant. Modulating the expression levels of specific miRNAs holds promise for developing novel therapeutic strategies to enhance bone formation, prevent bone loss, and promote bone regeneration. Potential therapeutic approaches include the use of synthetic miRNA mimics to restore miRNA expression in diseases associated with miRNA downregulation or the use of anti-miRNA oligonucleotides to inhibit miRNA function in diseases associated with miRNA upregulation.miRNA-based therapies are still in the early stages of development, and further research is needed to fully understand the complexity of miRNA networks. Additionally, the delivery of miRNAs to specific target tissues and cells remains a challenge that needs to be addressed for effective clinical translation. Nonetheless, targeting osteoblastic miRNAs represents a promising avenue for future therapeutic interventions in skeletal diseases. (AU)
Los micro-ARNs (miARNss) son pequeños ARN no codificantes que desempeñan un papel fundamental en la regulación génica postranscripcional. Ejercen su función al unir-se a moléculas de ARN mensajero (ARNm), promoviendo su degradación e inhibiendo su traducción en proteínas. En el contexto de las enfermedades esqueléticas, como la osteoporosis, la osteoartritis y la metástasis ósea existe evidencia de que los miARNs osteoblásticos están involucrados en la regulación de la formación y del mantenimiento óseo. Los osteoblastos son células formadoras de hueso responsables de sintetizar y depositar la matriz extracelular, que finalmente se mineraliza para formar el hueso. Los miARNs derivados de osteoblastos modulan varios aspectos de la función de estas células, incluida la proliferación, diferenciación, mineralización y la apoptosis. La desregulación de estos miARNs puede alterar el equilibrio entre la formación y la resorción ósea, lo que lleva a enfermedades óseas. Las implicaciones terapéuticas de los miARNs osteoblásticos en enfermedades esqueléticas son significativas. La modulación de los niveles de expresión de miARNs específicos es prometedora para desarrollar nuevas estrate-gias terapéuticas a fin de mejorar la formación, prevenir la pérdida y promover la regeneración ósea. Los enfoques terapéuticos potenciales incluyen el uso de miméticos de miARNs para restaurar la expresión de miARNs o el uso de oligonucleótidos anti-miARNs para inhibir su función. Las terapias basadas en miARNs aún se encuentran en las primeras etapas de desarrollo. La administración de miARNs a las células y los tejidos específicos sigue siendo un desafío para lograr una aplicación clínica eficaz. (AU)
Assuntos
Humanos , Osteoblastos/citologia , Osteogênese/genética , MicroRNAs/genética , Osteoclastos/citologia , Doenças Ósseas/prevenção & controle , Transdução de Sinais , Regulação da Expressão Gênica , MicroRNAs/biossíntese , MicroRNAs/fisiologia , MicroRNAs/uso terapêuticoRESUMO
Titanium and its alloys are used as biomaterials for medical and dental applications, due to their mechanical and physical properties. Surface modifications of titanium with bioactive molecules can increase the osseointegration by improving the interface between the bone and implant. In this work, titanium dioxide nanotubes (TiO2NTs) were functionalized with a lectin from the plasma of the fish Oreochromis niloticus aiming to favor the adhesion and proliferation of osteoblast-like cells, improving its biocompatibility. The TiO2NTs were obtained by anodization of titanium and annealed at 400 °C for 3 h. The resulting TiO2NTs were characterized by high-resolution scanning electron microscopy. The successful incorporation of OniL on the surface of TiO2NTs, by spin coating, was demonstrated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIE), and attenuated total reflection-Fourier transform infrared spectrum (ATR-FTIR). Our results showed that TiO2NTs were successfully synthesized in a regular and well-distributed way. The modification of TiO2NTs with OniL favored adhesion, proliferation, and the osteogenic activity of osteoblast-like cells, suggesting its use to improve the quality and biocompatibility of titanium-based biomaterials.
Assuntos
Ciclídeos/metabolismo , Lectinas/química , Osteoblastos/citologia , Titânio/farmacologia , Ligas , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia Dielétrica , Microscopia Eletrônica de Varredura , Nanotubos , Osteogênese , Propriedades de Superfície , Titânio/químicaRESUMO
Composite scaffolds are commonly used strategies and materials employed to achieve similar analogs of bone tissue. This study aims to fabricate 10% wt polylactic acid (PLA) composite fiber scaffolds by the air-jet spinning technique (AJS) doped with 0.5 or 0.1 g of zirconium oxide nanoparticles (ZrO2) for guide bone tissue engineering. ZrO2 nanoparticles were obtained by the hydrothermal method and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). SEM and fourier-transform infrared spectroscopy (FTIR) analyzed the synthesized PLA/ZrO2 fiber scaffolds. The in vitro biocompatibility and bioactivity of the PLA/ZrO2 were studied using human fetal osteoblast cells. Our results showed that the hydrothermal technique allowed ZrO2 nanoparticles to be obtained. SEM analysis showed that PLA/ZrO2 composite has a fiber diameter of 395 nm, and the FITR spectra confirmed that the scaffolds' chemical characteristics are not affected by the synthesized technique. In vitro studies demonstrated that PLA/ZrO2 scaffolds increased cell adhesion, cellular proliferation, and biomineralization of osteoblasts. In conclusion, the PLA/ZrO2 scaffolds are bioactive, improve osteoblasts behavior, and can be used in tissue bone engineering applications.
Assuntos
Nanopartículas/química , Osteoblastos/metabolismo , Poliésteres/química , Engenharia Tecidual , Alicerces Teciduais/química , Zircônio/química , Calcificação Fisiológica , Adesão Celular , Linhagem Celular , Proliferação de Células , Humanos , Osteoblastos/citologiaRESUMO
Polymeric nanoparticles have previously been used as substrates for cell attachment and proliferation due to their ability to mimic the extracellular matrix, but in general, they require surface chemical modifications to achieve this purpose. In this study, polymeric nanoparticles were developed and used without any matrix ligands functionalized on their surface to promote cell attachment and proliferation of human osteoblasts (MG63s). First, telechelic, reduced molar mass and diol-functionalized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was prepared by transesterification using ethylene glycol. Then, PHBV-diol was used to prepare biodegradable nanoparticles via the solvent evaporation technique. MG63s were cultured in the presence of PHBV nanoparticles and growth kinetics were compared to that on tissue culture polystyrene (TCPS). Cell attachment on non-tissue culture polystyrene pre-coated with nanoparticles was assessed and compared to attachment on TCPS. The cell attachment study demonstrated that cells readily attached and were well spread onto the nanoparticle surfaces compared to non-tissue culture polystyrene. These findings reveal the potential of PHBV nanoparticles for cell attachment and growth to be used in tissue engineering.
Assuntos
Nanopartículas/química , Osteoblastos/citologia , Poliésteres/farmacologia , Varredura Diferencial de Calorimetria , Adesão Celular/efeitos dos fármacos , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Humanos , Hidrodinâmica , Ligantes , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Poliésteres/química , Espectroscopia de Prótons por Ressonância Magnética , Eletricidade Estática , TemperaturaRESUMO
The aim of this study was to evaluate biocompatibility of hydroxyapatite (HAP) from fish waste using in vitro and in vivo assays. Fish samples (whitemouth croaker - Micropogonias furnieri) from the biowaste was used as HAP source. Pre-osteoblastic MC3T3-E1 cells were used in vitro study. In addition, bone defects were artificially created in rat calvaria and filled with HAP in vivo. The results demonstrated that HAP reduced cytotoxicity in pre-osteoblast cells after 3 and 6 days following HAP exposure. DNA concentration was lower in the HAP group after 6 days. Quantitative RT-PCR did not show any significant differences (p > 0.05) between groups. In vivo study revealed that bone defects filled with HAP pointed out moderate chronic inflammatory cells with slight proliferation of blood vessels after 7 and 15 days. Chronic inflammatory infiltrate was absent after 30 days of HAP exposure. There was also a decrease in the amount of biomaterial, being followed by newly formed bone tissue. All experimental groups also demonstrated strong RUNX-2 immoexpression in the granulation tissue as well as in cells in close contact with biomaterial. The number of osteoblasts inside the defect area was lower in the HAP group when compared to control group after 7 days post-implantation. Similarly, the osteoblast surface as well as the percentage of bone surface was higher in control group when compared with HAP group after 7 days post-implantation. Taken together, HAP from fish waste is a promising possibility that should be explored more carefully by tissue-engineering or biotechnology.
Assuntos
Durapatita/isolamento & purificação , Durapatita/farmacologia , Produtos Pesqueiros , Animais , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/química , Substitutos Ósseos/isolamento & purificação , Substitutos Ósseos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Produtos Pesqueiros/análise , Teste de Materiais , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Perciformes , Ratos , Crânio/efeitos dos fármacos , Crânio/fisiologia , Resíduos Sólidos/análiseRESUMO
The extracellular matrix protein Agrin has been detected in chondrocytes and endosteal osteoblasts but its function in osteoblast differentiation has not been investigated yet. Thus, it is possible that Agrin contributes to osteoblast differentiation and, due to Agrin and wingless-related integration site (Wnt) sharing the same receptor, transmembrane low-density lipoprotein receptor-related protein 4 (Lrp4), and the crosstalk between Wnt and bone morphogenetic protein (BMP) signalling, both pathways could be involved in this Agrin-mediated osteoblast differentiation. Confirming this, Agrin and its receptors Lrp4 and α-dystroglycan (Dag1) were expressed during differentiation of osteoblasts from three different sources. Moreover, the disruption of Agrin impaired the expression of its receptors and osteoblast differentiation, and the treatment with recombinant Agrin slightly increase this process. In addition, whilst Agrin knockdown downregulated the expression of genes related to Wnt and BMP signalling pathways, the addition of Agrin had no effect on these genes. Altogether, these data uncover the contribution of Agrin to osteoblast differentiation and suggest that, at least in part, an Agrin-Wnt-BMP circuit is involved in this process. This makes Agrin a candidate as target for developing new therapeutic strategies to treat bone-related diseases and injuries.
Assuntos
Agrina/análise , Osteoblastos/citologia , Células 3T3 , Agrina/genética , Animais , Diferenciação Celular , Células Cultivadas , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/metabolismo , OsteogêneseRESUMO
MicroRNA-9 (miR-9) modulates gene expression and demonstrates high structural conservation and wide expression in the central nervous system. Bioinformatics analysis predicts almost 100 ion channels, membrane transporters and receptors, including genes linked to primary familial brain calcification (PFBC), as possible miR-9-5p targets. PFBC is a neurodegenerative disorder, characterized by bilateral and symmetrical calcifications in the brain, associated with motor and behavioral disturbances. In this work, we seek to study the influence of miR-9-5p in regulating genes involved in PFBC, in an osteogenic differentiation model with SaOs-2 cells. During the induced calcification process, solute carrier family 20 member 2 (SLC20A2) and platelet-derived growth factor receptor beta (PDGFRB) were downregulated, while platelet-derived growth factor beta (PDGFB) showed no significant changes. Significantly decreased levels of SLC20A2 and PDGFRB were caused by the presence of miR-9-5p, while PDGFB showed no regulation. We confirmed the findings using an miR-9-5p inhibitor and also probed the cells in electrophysiological analysis to assess whether such microRNA might affect a broader range of ion channels, membrane transporters and receptors. Our electrophysiological data show that an increase of the miR-9-5p in SaOs-2 cells decreased the density and amplitude of the output ionic currents, indicating that it may influence the activity, and perhaps the expression, of some ionic channels. Additional investigations should determine whether such an effect is specific to miR-9-5p, and whether it could be used, together with the miR-9-5p inhibitor, as a therapeutic or diagnostic tool.
Assuntos
Encefalopatias/metabolismo , Calcinose/metabolismo , Diferenciação Celular , MicroRNAs/metabolismo , Osteoblastos/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Potenciais de Ação , Encefalopatias/genética , Calcinose/genética , Linhagem Celular Tumoral , Humanos , MicroRNAs/genética , Osteoblastos/citologia , Osteoblastos/fisiologia , Proteínas Proto-Oncogênicas c-sis/genética , Proteínas Proto-Oncogênicas c-sis/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genéticaRESUMO
Calcium phosphosilicate nanoparticles (CPSNPs) are bioresorbable nanoparticles that can be bioconjugated with targeting molecules and encapsulate active agents and deliver them to tumor cells without causing damage to adjacent healthy tissue. Data obtained in this study demonstrated that an anti-CD71 antibody on CPSNPs targets these nanoparticles and enhances their internalization by triple negative breast cancer cells in-vitro. Caspase 3,7 activation, DNA damage, and fluorescent microscopy confirmed the apoptotic breast cancer response caused by targeted anti-CD71-CPSNPs encapsulated with gemcitabine monophosphate, the active metabolite of the chemotherapeutic gemcitabine used to treat cancers including breast and ovarian. Targeted anti-CD71-CPSNPs encapsulated with the fluorophore, Rhodamine WT, were preferentially internalized by breast cancer cells in co-cultures with osteoblasts. While osteoblasts partially internalized anti-CD71-GemMP-CPSNPs, their cell growth was not affected. These results suggest that CPSNPs may be used as imaging tools and selective drug delivery systems for breast cancer that has metastasized to bone.
Assuntos
Anticorpos/metabolismo , Compostos de Cálcio/metabolismo , Nanopartículas , Metástase Neoplásica , Osteoblastos/citologia , Silicatos/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Células 3T3 , Animais , Técnicas de Cocultura , Feminino , Humanos , Camundongos , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
Checkpoint Kinase 1 (Chk1) prevents DNA damage by adjusting the replication choreography in the face of replication stress. Chk1 depletion provokes slow and asymmetrical fork movement, yet the signals governing such changes remain unclear. We sought to investigate whether poly(ADP-ribose) polymerases (PARPs), key players of the DNA damage response, intervene in the DNA replication of Chk1-depleted cells. We demonstrate that PARP inhibition selectively alleviates the reduced fork elongation rates, without relieving fork asymmetry in Chk1-depleted cells. While the contribution of PARPs to fork elongation is not unprecedented, we found that their role in Chk1-depleted cells extends beyond fork movement. PARP-dependent fork deceleration induced mild dormant origin firing upon Chk1 depletion, augmenting the global rates of DNA synthesis. Thus, we have identified PARPs as novel regulators of replication fork dynamics in Chk1-depleted cells.