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1.
Int J Nanomedicine ; 15: 5825-5838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821104

RESUMO

Background and Purpose: The extracellular matrix (ECM) derived from bone marrow mesenchymal stem cells (BMSCs) has been used in regenerative medicine because of its good biological activity; however, its poor mechanical properties limit its application in bone regeneration. The purpose of this study is to construct a three dimensional-printed hydroxyapatite (3D-HA)/BMSC-ECM composite scaffold that not only has biological activity but also sufficient mechanical strength and reasonably distributed spatial structure. Methods: A BMSC-ECM was first extracted and formed into micron-sized particles, and then the ECM particles were modified onto the surface of 3D-HA scaffolds using an innovative linking method to generate composite 3D-HA/BMSC-ECM scaffolds. The 3D-HA scaffolds were used as the control group. The basic properties, biocompatibility and osteogenesis ability of both scaffolds were tested in vitro. Finally, a critical skull defect rat model was created and the osteogenesis effect of the scaffolds was evaluated in vivo. Results: The compressive modulus of the composite scaffolds reached 9.45±0.32 MPa, which was similar to that of the 3D-HA scaffolds (p>0.05). The pore size of the two scaffolds was 305±47 um and 315±34 um (p>0.05), respectively. A CCK-8 assay indicated that the scaffolds did not have cytotoxicity. The composite scaffolds had good cell adhesion ability, with a cell adhesion rate of up to 76.00±6.17% after culturing for 7 hours, while that of the 3D-HA scaffolds was 51.85±4.77% (p<0.01). In addition, the composite scaffold displayed higher alkaline phosphatase (ALP) activity, osteogenesis-related mRNA expression, and calcium nodule formation, thus confirming that the composite scaffolds had good osteogenic activity. The composite scaffolds exhibited good bone repair in vivo and were superior to the 3D-HA scaffolds. Conclusion: We conclude that BMSC-ECM is a good osteogenic material and that the composite scaffolds have good osteogenic ability, which provides a new method and concept for the repair of bone defects.


Assuntos
Durapatita/farmacologia , Matriz Extracelular/metabolismo , Células-Tronco Mesenquimais/citologia , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Hidrodinâmica , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
2.
Life Sci ; 258: 118195, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781073

RESUMO

AIMS: The estrogen-ERα axis participates in osteoblast maturation. This study was designed to further evaluated the roles of the estrogen-ERα axis in bone healing and the possible mechanisms. MAIN METHODS: Female ICR mice were created a metaphyseal bone defect in the left femurs and administered with methylpiperidinopyrazole (MPP), an inhibitor of ERα. Bone healing was evaluated using micro-computed tomography. Colocalization of ERα with alkaline phosphatase (ALP) and ERα translocation to mitochondria were determined. Levels of ERα, ERß, PECAM-1, VEGF, and ß-actin were immunodetected. Expression of chromosomal Runx2, ALP, and osteocalcin mRNAs and mitochondrial cytochrome c oxidase (COX) I and COXII mRNAs were quantified. Angiogenesis was measured with immunohistochemistry. KEY FINDINGS: Following surgery, the bone mass was time-dependently augmented in the bone-defect area. Simultaneously, levels of ERα were specifically upregulated and positively correlated with bone healing. Administration of MPP to mice consistently decreased levels of ERα and bone healing. As to the mechanisms, osteogenesis was enhanced in bone healing, but MPP attenuated osteoblast maturation. In parallel, expressions of osteogenesis-related ALP, Runx2, and osteocalcin mRNAs were induced in the injured zone. Treatment with MPP led to significant inhibition of the alp, runx2, and osteocalcin gene expressions. Remarkably, administration of MPP lessened translocation of ERα to mitochondria and expressions of mitochondrial energy production-related coxI and coxII genes. Furthermore, exposure to MPP decreased levels of PECAM-1 and VEGF in the bone-defect area. SIGNIFICANCE: The present study showed the contributions of the estrogen-ERα axis to bone healing through stimulation of energy production, osteoblast maturation, and angiogenesis.


Assuntos
Regeneração Óssea , Diferenciação Celular , Metabolismo Energético , Receptor alfa de Estrogênio/metabolismo , Neovascularização Fisiológica , Osteoblastos/citologia , Transdução de Sinais , Fosfatase Alcalina/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Calo Ósseo/efeitos dos fármacos , Calo Ósseo/patologia , Diferenciação Celular/efeitos dos fármacos , Cromossomos de Mamíferos/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Camundongos Endogâmicos ICR , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Regulação para Cima/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
3.
PLoS One ; 15(8): e0237660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841254

RESUMO

This study evaluated the influence of type 2 diabetes mellitus on bone loss, bone repair and cytokine production in hyperglycemic rats, treated or not with metformin. The animals were distributed as follow: Non-Hyperglycemic (NH), Non Hyperglycemic with Ligature (NH-L), Treated Non Hyperglycemic (TNH), Treated Non Hyperglycemic with Ligature Treated (TNH-L), Hyperglycemic (H), Treated Hyperglycemic (TH), Hyperglycemic with Ligature (H-L), Treated Hyperglycemic with Ligature (TH-L). At 40th day after induction of hyperglycemia, the groups NH-L, TNH-L, H-L, TH-L received a ligature to induce periodontitis. On the 69th, the TNH, TNH-L, TH, TH-L groups received metformin until the end of the study. Bone repair was evaluated at histometric and the expression levels of Sox9, RunX2 and Osterix. Analysis of the ex-vivo expression of TNF-α, IFN-γ, IL-12, IL-4, TGF-ß, IL-10, IL-6 and IL-17 were also evaluated. Metformin partially reverse induced bone loss in NH and H animals. Lower OPG/RANKL, increased OCN and TRAP expression were observed in hyperglycemic animals, and treatment with metformin partially reversed hyperglycemia on the OPG/RANKL, OPN and TRAP expression in the periodontitis. The expression of SOX9 and RunX2 were also decreased by hyperglycemia and metformin treatment. Increased ex vivo levels of TNF-α, IL-6, IL-4, IL-10 and IL-17 was observed. Hyperglycemia promoted increased IL-10 levels compared to non-hyperglycemic ones. Treatment of NH with metformin was able to mediate increased levels of TNF-α, IL-10 and IL-17, whereas for H an increase of TNF-α and IL-17 was detected in the 24- or 48-hour after stimulation with LPS. Ligature was able to induce increased levels of TNF-α and IL-17 in both NH and H. This study revealed the negative impact of hyperglycemia and/or treatment with metformin in the bone repair via inhibition of transcription factors associated with osteoblastic differentiation.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/complicações , Hiperglicemia/complicações , Metformina/administração & dosagem , Periodontite/prevenção & controle , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/metabolismo , Processo Alveolar/citologia , Processo Alveolar/efeitos dos fármacos , Processo Alveolar/metabolismo , Processo Alveolar/patologia , Animais , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/genética , Diferenciação Celular/efeitos dos fármacos , Citocinas/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Hiperglicemia/induzido quimicamente , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Osteoblastos/fisiologia , Periodontite/etiologia , Periodontite/metabolismo , Ratos , Estreptozocina/toxicidade , Fatores de Transcrição/metabolismo
4.
Life Sci ; 257: 118038, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32622947

RESUMO

PURPOSE: The importance of regeneration in large bone defects forces the orthopedic surgeons to search for a proper methodology. The present experiment evaluated the capability of polylactic acid/polycaprolactone/hydroxyapatite (PLA/PCL/HA) scaffold loaded with and without mesenchymal stem cells (MSCs) on bone regeneration. METHODS: Fourier transform infrared spectrometry, X-ray diffraction, scanning electron microscopy, and rheology methodologies were used to characterize the scaffold. Forty Wistar rats were randomly divided into the four groups including the untreated defects as the control group and three other groups in which the bone defects were treated with autologous bones (autograft group), the PLA/PCL/HA scaffolds (PLA/PCL/HA group), and the MSCs-seeded scaffolds (MSCs-seeded PLA/PCL/HA group). RESULTS: Based on the qRT-PCR results, significantly higher expression levels of osteocalcin, osteopontin, and CD31 were seen in the cell-seeded scaffold group compared to the control group (P < 0.05). The CT scanning and radiographic images depicted significantly more newly formed bonny tissue in the MSCs-loaded scaffold and autograft groups than the untreated group (P < 0.001). The immunohistochemistry, biomechanical, histopathologic, and histomorphometric evaluations demonstrated significantly improved regeneration in the autograft and MSCs-loaded scaffold groups compared to the non-treated group (P < 0.05). There were significant differences between the scaffold and untreated groups in all in vivo evaluations (P < 0.05). CONCLUSION: The MSCs enhanced bone healing potential of the PLA/PCL/HA scaffold and the MSCs-seeded scaffold was comparable to the autograft as the golden treatment regimen (P > 0.05).


Assuntos
Regeneração Óssea/fisiologia , Transplante de Células-Tronco Mesenquimais/métodos , Engenharia Tecidual/métodos , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Durapatita/química , Masculino , Células-Tronco Mesenquimais/fisiologia , Poliésteres/química , Rádio (Anatomia)/metabolismo , Ratos , Ratos Wistar , Tecidos Suporte/química
5.
Int. j. morphol ; 38(3): 683-688, June 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1098307

RESUMO

The aim was to evaluate bone repair and gingival tissue repair in osteopenic rats. Fifteen female wistar rats were included; in all of them ovariectomy was realized to induce osteopenia; after 45 days, the animals were submitted to 2 surgical techinques 1) dental extraction of the upper central incisor with no socket preservation and 2) 5 mm cranial defect in the calvarium; 5 rats were included in the control group (G1) withput alendronate application; in the group 2 (G2) was used subcutenous alendronate (0.5 mg/kg) once for three weeks and then was realizd the both surgical techniques. In group 3 (G3), after ovariectomy was realized the both dental extraction and the calvarium defect and after that was realized the alendronate protocol. In each group, after six week was realized euthanasia and descriptive histological analysis of the surgical areas involved. In bone formation of the 5 mm cranial defect was observed with good progression in the 3 experimental models and no modification in quality of bone repair was observed. For the gingival tissue in the extraction socket, no differences were observed between G1 and G3. On other hand, in G2 a thinner and reduced gingival epithelium was found. Our results showed that alendronate was not an obstacle for bone repair; deficiencies in re-epithelialization of oral mucosa show the impact of alendronate before dental extraction.


El objetivo fue evaluar la reparación ósea y gingival en ratas con osteopenia. Quince ratas wistar hembras fueron incluidas; en todas ellas se realizo ovarectomia y fue realizada la inducción de osteopenia; después de 45 días, los animales fueron sometidos a dos técnicas quirúrgicas 1) extracciones dentales del incisivo central superior sin preservación alveolar y 2) creación de un defecto craneano de 5 mm en la calota; 5 animales fueron incluidos como grupo control (G1) sin la aplicación de alendronato; en el grupo 2 (G2) se utilizó alendronato subcutáneo (0,5 mg/kg) una vez a la semana durante 3 semanas. En el grupo 3 (G3), después de la ovarectomia se realizó la exodoncia y el defecto en el cráneo y después de ello se inicio el protocolo con alendronato. En cada grupo, después de seis semanas se realizó la eutanasia con descripción histológica de los hallazgos. En el hueso formado en el defecto craneano de 5 mm se observó una adecuada progresión de reparación en los 3 modelos experimentales y no se observó cambios importantes en el modelo de reparación. Para el tejido gingival en el sitio de extracción, no se observaron diferencias entre el grupo G1 y G3. Por otra parte, el G2 presentó un tejido mas delgado con reducción del epitelio gingival; nuestros resultados demuestran que el alendronato no fue un obstáculo en la reparación ósea; deficiencias en la re epitelización de la mucosa oral muestran el impacto del alendronato después de la exodoncia.


Assuntos
Animais , Feminino , Ratos , Doenças Ósseas Metabólicas/tratamento farmacológico , Regeneração Óssea/efeitos dos fármacos , Alendronato/administração & dosagem , Gengiva/efeitos dos fármacos , Osteonecrose/tratamento farmacológico , Osteoporose/tratamento farmacológico , Doenças Ósseas Metabólicas/complicações , Ovariectomia , Ratos Wistar , Difosfonatos/administração & dosagem
6.
Life Sci ; 254: 117768, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32407840

RESUMO

AIMS: In this study, we used a cross-junction microfluidic device for preparation of alendronate-loaded chitosan nanoparticles with desired characteristics to introduce a suitable element for bone tissue engineering scaffolds. MAIN METHODS: By controlling the reaction condition in microfluidic device, six types of alendronate-loaded chitosan nanoparticles were fabricated which had different physical properties. Hydrodynamic diameter of synthetized particles was evaluated by dynamic light scattering (102 to 215 nm). Nanoparticle morphology was determined by SEM and AFM images. The osteogenic effects of prepared selected nanoparticles on human adipose stem cells (hA-MSCs) were evaluated by assessment of alkaline phosphatase (ALP) activity, calcium deposition, ALP and osteopontin gene expression. KEY FINDINGS: The highest loading efficiency percentage (%LE) was %32.42 ± 2.02. Based on MTT assessment, two samples which had no significant cytotoxicity were chosen for further studies (particle sizes and %LE were 142 ± 6.1 nm, 198 ± 16.56 nm, %16.76 ± 3.91 and %32.42 ± 2.02, respectively). In vitro release behavior of nanoparticles displayed pH responsive characteristics. Significant faster release was seen in acidic pH = 5.8 than neutral pH = 7.4. The selected nanoparticles demonstrated higher ALP activity at 14 days in comparison to selected blank sample and osteogenic differentiation media (ODM) and a downregulation at 21 days in comparison to 14 days. Calcium content assay at 21 days displayed significant differences between alendronate-loaded nanoparticles and ODM. ALP and osteopontin mRNA expression was significantly higher than the cells cultured in ODM at 14 and 21 days. SIGNIFICANCE: We concluded that our prepared nanoparticles significantly enhanced osteogenic differentiation of hA-MSCs and can be a suitable compartment of bone tissue engineering scaffolds.


Assuntos
Alendronato/metabolismo , Osteogênese/efeitos dos fármacos , Engenharia Tecidual/instrumentação , Adipócitos , Animais , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana/metabolismo , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Microfluídica/métodos , Nanopartículas , Células-Tronco/efeitos dos fármacos , Engenharia Tecidual/métodos , Tecidos Suporte
7.
Int J Nanomedicine ; 15: 3039-3056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431500

RESUMO

Background: Electrospinning is a widely used technology that can produce scaffolds with high porosity and surface area for bone regeneration. However, the small pore sizes in electrospun scaffolds constrain cell growth and tissue-ingrowth. In this study, novel drug-loading core-shell scaffolds were fabricated via electrospinning and freeze drying to facilitate the repair of tibia bone defects in rabbit models. Materials and Methods: The collagen core scaffolds were freeze-dried containing icariin (ICA)-loaded chitosan microspheres. The shell scaffolds were electrospun using collagen, polycaprolactone and hydroxyapatite materials to form CPH composite scaffolds with the ones containing ICA microspheres named CPHI. The core-shell scaffolds were then cross-linked by genipin. The morphology, microstructure, physical and mechanical properties of the scaffolds were assessed. Rat marrow mesenchymal stem cells from the wistar rat were cultured with the scaffolds. The cell adhesion and proliferation were analysed. Adult rabbit models with tibial plateau defects were used to evaluate the performance of these scaffolds in repairing the bone defects over 4 to 12 weeks. Results: The results reveal that the novel drug-loading core-shell scaffolds were successfully fabricated, which showed good physical and chemical properties and appropriate mechanical properties. Furthermore, excellent cells attachment was observed on the CPHI scaffolds. The results from radiography, micro-computed tomography, histological and immunohistochemical analysis demonstrated that abundant new bones were formed on the CPHI scaffolds. Conclusion: These new core-shell composite scaffolds have great potential for bone tissue engineering applications and may lead to effective bone regeneration and repair.


Assuntos
Regeneração Óssea , Flavonoides/farmacologia , Tíbia/efeitos dos fármacos , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Quitosana/química , Colágeno/química , Durapatita/química , Flavonoides/administração & dosagem , Flavonoides/química , Masculino , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Microesferas , Poliésteres/química , Porosidade , Coelhos , Ratos Wistar , Tíbia/diagnóstico por imagem , Microtomografia por Raio-X
8.
Adv Clin Exp Med ; 29(4): 431-440, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32364686

RESUMO

BACKGROUND: Autogenous or allogenic bone transplantation is the main treatment for bone defects and nonunions. However, the shortcomings of autogenous or allogenic bone transplantation limit its wide application in clinical use. OBJECTIVES: This study investigated the effect of poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with pOsterix (pOsx)/polyethylenimine (PEI) nanoparticles in repairing bone defects and explored its mechanism. MATERIAL AND METHODS: Poly(lactic-co-glycolic acid) microspheres loaded with pOsx/PEI nanoparticles were constructed. The Osx transfection effect was detected by fluorescence quantitative PCR and western blotting methods. 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-diphenytetrazoliumromide (MTT) and flow cytometry methods were used to detect cell proliferation. The collagen I (Col-1), osteopontin (OPN) and osteocalcin (OC) expression levels were detected using real-time polymerase chain reaction (RT-PCR) and western blotting methods. Bone defect model was constructed. Bone repair was detected using X-ray, hematoxylin and eosin (H&E) staining, and Mason staining methods. RESULTS: PLGA@pOsx/PEI has transfection effect both in vitro and in vivo, does not affect cell proliferation and is safe for cells. PLGA@pOsx/PEI could promote the expression of Col-1, OPN and OC in vitro and in vivo. PLGA@pOsx/PEI could promote osteogenesis in vivo. CONCLUSIONS: PLGA@pOsx/PEI with high Osx expression could promote the expression of OC, OPN, and COL-I. PLGA@pOsx/PEI can be used as a material for repairing bone defects and can promote bone formation. These results provide a theoretical and practical basis for its further clinical application.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Ácido Láctico/química , Nanopartículas , Polietilenoimina/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Western Blotting , Proliferação de Células/efeitos dos fármacos , Microesferas , Reação em Cadeia da Polimerase em Tempo Real
9.
Int J Nanomedicine ; 15: 2363-2378, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308388

RESUMO

Biomaterials with porous structure and high surface area attract growing interest in biomedical research and applications. Aerogel-based biomaterials, as highly porous materials that are made from different sources of macromolecules, inorganic materials, and composites, mimic the structures of the biological extracellular matrix (ECM), which is a three-dimensional network of natural macromolecules (e.g., collagen and glycoproteins), and provide structural support and exert biochemical effects to surrounding cells in tissues. In recent years, the higher requirements on biomaterials significantly promote the design and development of aerogel-based biomaterials with high biocompatibility and biological activity. These biomaterials with multilevel hierarchical structures display excellent biological functions by promoting cell adhesion, proliferation, and differentiation, which are critical for biomedical applications. This review highlights and discusses the recent progress in the preparation of aerogel-based biomaterials and their biomedical applications, including wound healing, bone regeneration, and drug delivery. Moreover, the current review provides different strategies for modulating the biological performance of aerogel-based biomaterials and further sheds light on the current status of these materials in biomedical research.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Sistemas de Liberação de Medicamentos/métodos , Cicatrização/efeitos dos fármacos , Animais , Regeneração Óssea/efeitos dos fármacos , Colágeno/química , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Humanos , Porosidade
10.
Int. j. morphol ; 38(2): 316-321, abr. 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1056441

RESUMO

La regeneración de defectos óseos críticos requiere la utilización de biomateriales óseos. Así, se han utilizados agentes osteogénicos como la proteína morfogenética (rhBMP-2). El objetivo fue describir la formación ósea de defectos óseos críticos en calota de ratas utilizando rhBMP-2 con distintos biomateriales. Se realizaron dos defectos óseos críticos de 5 mm en 15 calotas de ratas machos adultas divididos en grupo control (sin tratamiento) (C); autoinjerto + rhBMP-2 (A); fosfato tricálcico + rhBMP-2 (BTCP); xenoinjerto de bovino + rhBMP-2 (B) y hidroxihapatita + rhBMP-2 (HA). A las ocho semanas post tratamiento, se realizó la eutanasia y posterior análisis histológico de los defectos. El grupo C no presentó formación de tejido óseo en el defecto. En el resto de los grupos, se formó abundante tejido óseo en los márgenes, por lo tanto, el defecto presentó menor tamaño. El grupo HA presentó formación ósea trabecular con amplios espacios medulares y abundante tejido adiposo. El grupo B-TCP también presentó formación ósea trabecular y la mayoría de las muestras presentaron puente óseo en el defecto. El grupo B presentó partículas de material injertado rodeado por trabéculas óseas y tejido conectivo. En el grupo A, todas las muestras presentaban puente óseo formado por bloques de autoinjerto rodeado por tejido conectivo y óseo. Es posible concluir que los defectos óseos de 5 mm en calota de rata son defectos críticos que requieren utilizar biomateriales para la reparación del defecto. El grupo B-TCP presentó características histológicas más próximas a la regeneración ósea lograda con el Grupo A.


The regeneration of bone critical size defects requires the use of bone biomaterials. Therefore, an osteogenic agent such as bone morphogenetic protein (rhBMP-2) has been used. The objective was to describe the bone formation of bone critical size defects in the rat calvaria using rhBMP-2 with different biomaterials. Two critical bone defects of 5 mm were made in 15 calvaria of adult male rats divided into a control group (without treatment) (C); autograft + rhBMP-2 (A); tricalcium phosphate + rhBMP-2 (B-TCP); bovine xenograft + rhBMP-2 (B) and hydroxyhapatite + rhBMP-2 (HA). At eight weeks post treatment, euthanasia and subsequent histological analysis of the defects were performed. Group C did not show bone tissue formation in the defect. In the rest of the groups, abundant bone tissue formed in the margins, therefore, the defect was smaller. The HA group presented trabecular bone formation with large medullary spaces and abundant adipose tissue. The B-TCP group also presented trabecular bone formation and most of the samples formed a bone bridge across the defect. Group B presented grafted material particles surrounded by bone trabeculae and connective tissue. In group A, all samples presented a bone bridge formed by autograft blocks surrounded by connective and bone tissue. It is possible to conclude that 5 mm bone defects in rat calvaria are critical size defects that require the use of biomaterials for defect repair. The B-TCP group presented histological characteristics similar to the bone regeneration achieved with Group A.


Assuntos
Animais , Masculino , Ratos , Regeneração Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2/farmacologia , Materiais Biocompatíveis , Ratos Sprague-Dawley
11.
Int J Nanomedicine ; 15: 2045-2058, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273701

RESUMO

Bone regeneration remains a great clinical challenge. Two-dimensional materials, especially graphene and its derivative graphene oxide, have been widely used for bone regeneration. Since its discovery in 2014, black phosphorus (BP) nanomaterials including BP nanosheets and BP quantum dots have attracted considerable scientific attention and are considered as prospective graphene substitutes. BP nanomaterials exhibit numerous advantages such as excellent optical and mechanical properties, electrical conductivity, excellent biocompatibility, and good biodegradation, all of which make them particularly attractive in biomedicine. In this review, we comprehensively summarize recent advances of BP-based nanomaterials in bone regeneration. The advantages are reviewed, the different synthesis methods of BP are summarized, and the applications to promote bone regeneration are highlighted. Finally, the existing challenges and perspectives of BP in bone regeneration are briefly discussed.


Assuntos
Regeneração Óssea/fisiologia , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Fósforo/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Grafite/química , Humanos , Pontos Quânticos/química
12.
PLoS One ; 15(4): e0231112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310975

RESUMO

Tissue engineering represents a promising alternative for reconstructive surgical procedures especially for the repair of bone defects that do not regenerate spontaneously. The present study aimed to evaluate the effects of the elastin matrix (E24/50 and E96/37) incorporated with hydroxyapatite (HA) or morphogenetic protein (BMP) on the bone repair process in the distal metaphysis of rat femur. The groups were: control group (CG), hydrolyzed elastin matrix at 50°C/24h (E24/50), E24/50 + HA (E24/50/HA), E24/50 + BMP (E24/50/BMP), hydrolyzed elastin matrix at 37°C/96h (E96/37), E96/37 + HA (E96/37/HA), E96/37 + BMP (E96/37/BMP). Macroscopic and radiographic analyses showed longitudinal integrity of the femur in all groups without fractures or bone deformities. Microtomographically, all groups demonstrated partial closure by mineralized tissue except for the E96/37/HA group with hyperdense thin bridge formation interconnecting the edges of the ruptured cortical. Histologically, there was no complete cortical recovery in any group, but partial closure with trabecular bone. In defects filled with biomaterials, no chronic inflammatory response or foreign body type was observed. The mean volume of new bone formed was statistically significant higher in the E96/37/HA and E24/50 groups (71.28 ± 4.26 and 66.40 ± 3.69, respectively) than all the others. In the confocal analysis, it was observed that all groups presented new bone markings formed during the experimental period, being less evident in the CG group. Von Kossa staining revealed intense calcium deposits distributed in all groups. Qualitative analysis of collagen fibers under polarized light showed a predominance of red-orange birefringence in the newly regenerated bone with no difference between groups. It was concluded that the E24/50 and E96/37/HA groups promoted, with greater speed, the bone repair process in the distal metaphysis of rat femur.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fêmur/lesões , Osteogênese/efeitos dos fármacos , Engenharia Tecidual , Tecidos Suporte/química , Animais , Proteínas Morfogenéticas Ósseas/administração & dosagem , Modelos Animais de Doenças , Durapatita/administração & dosagem , Elastina/administração & dosagem , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Humanos , Masculino , Ratos , Fatores de Tempo , Microtomografia por Raio-X
13.
Cell Prolif ; 53(4): e12796, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32202021

RESUMO

OBJECTIVES: Bone regeneration is a complex process modulated by multiple growth factors and hormones during long regeneration period; thus, designing biomaterials with the capacity to deliver multiple bioactive molecules and obtain sustained release has gained an increasing popularity in recent years. This study is aimed to evaluate the effect of a novel core-shell electrospun fibre loaded with dexamethasone (DEX) and bone morphogenetic protein-2 (BMP-2) on bone regeneration. MATERIALS AND METHODS: The core-shell electrospun fibres were fabricated by coaxial electrospinning technology, which were composed of poly-D, L-lactide (PLA) shell and poly (ethylene glycol) (PEG) core embedded with BMP-2 and DEX-loaded micelles. Morphology, hydrophilicity, gradation, release profile of BMP-2 and DEX, and cytological behaviour on bone marrow mesenchymal stem cells (BMSCs) were characterized. Furthermore, the effect on bone regeneration was evaluated via critical-sized calvarial defect model. RESULTS: The electrospun fibres were featured by the core-shell fibrous architecture and a suitable degradation rate. The sustained release of DEX and BMP-2 was up to 562 hours. The osteogenic gene expression and calcium deposition of BMSCs were significantly enhanced, indicating the osteoinduction capacity of electrospun fibres. This core-shell fibre could accelerate repair of calvarial defects in vivo via synergistic effect. CONCLUSIONS: This core-shell electrospun fibre loaded with DEX and BMP-2 can act synergistically to enhance bone regeneration, which stands as a strong potential candidate for repairing bone defects.


Assuntos
Anti-Inflamatórios/uso terapêutico , Proteína Morfogenética Óssea 2/uso terapêutico , Regeneração Óssea/efeitos dos fármacos , Dexametasona/uso terapêutico , Tecidos Suporte/química , Animais , Anti-Inflamatórios/administração & dosagem , Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2/administração & dosagem , Células Cultivadas , Dexametasona/administração & dosagem , Sinergismo Farmacológico , Feminino , Humanos , Osteogênese/efeitos dos fármacos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Crânio/efeitos dos fármacos , Crânio/lesões
14.
Acta Cir Bras ; 35(1): e202000102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215463

RESUMO

PURPOSE: To evaluate the local effect of simvastatin (SVT) combined with deproteinized bovine bone (DBB) with hydroxyapatite/ß-tricalcium phosphate biphasic ceramics (HA/TCP) and with collagen sponge (CS) on bone repair in critical size defects (CSDs) in rat calvaria. METHODS: Forty-two 5-mm diameter CSDs were made bilaterally in the calvaria of 18 rats. The animals were allocated according to the type of biomaterial and associations used to fill the CSD. After 8 weeks, the animals were euthanized, and their calvaria were evaluated for repaired tissue composition using histologic and histometric analyses. RESULTS: In the histometric analysis, the use of SVT showed to increase bone formation in the CSDs when combined with all the bone substitutes tested in this study (p<0.05). Greater bone formation was observed in the groups with SVT compared to the groups without SVT. CONCLUSIONS: The use of SVT without the need for a vehicle and combined with a commercially available biomaterial may be a cheaper way to potentiate the formation of bone tissue without the need to produce new biomaterials. Therefore, SVT combined with DBB induced significantly greater new bone formation than did the other treatments.


Assuntos
Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Colágeno/farmacologia , Osteogênese/efeitos dos fármacos , Sinvastatina/farmacologia , Crânio/efeitos dos fármacos , Animais , Anticolesterolemiantes/farmacologia , Regeneração Óssea/efeitos dos fármacos , Transplante Ósseo/métodos , Bovinos , Modelos Animais de Doenças , Feminino , Ratos , Ratos Wistar , Crânio/cirurgia
15.
Lasers Med Sci ; 35(7): 1519-1529, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32026163

RESUMO

The aim of this study was to evaluate the osseointegration of implants placed in areas grafted with different osteoconductive bone substitutes irradiated with infrared low-level laser therapy (LLLT). Fifty-six rats were randomly allocated into 4 groups: DBB, bone defects filled with deproteinized bovine bone graft (DBB); HA/TCP, bone defects filled with biphasic ceramic made of hydroxyapatite and ß-tricalcium phosphate (HA/TCP); DBB-L, bone defects filled with DBB and treated by LLLT; HA/TCP-L, bone defects filled with HA/TCP and treated by LLLT. Bone defects were performed in the tibia of each animal and filled with the different biomaterials. The grafted areas were treated with LLLT (λ 808 nm, 100 mW, ϕ ∼ 0.60 mm) in 7 sessions with 48 h between the irradiations. After the 60-day period, the implants were placed, and the animals were euthanized after 15 and 45 days. The osseointegration and bone repair in the grafted area were evaluated by biomechanical, microtomographic and histometric analyses, and the expression of some bone biomarkers was evaluated by immunohistochemistry analysis. LLLT induced higher degree of osseointegration, which was associated with the greater expression of BMP2 and OCN. LLLT performed in areas grafted with osteoconductive bone substitutes prior to implant placement improves osseointegration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/efeitos da radiação , Substitutos Ósseos/farmacologia , Terapia com Luz de Baixa Intensidade , Osseointegração/efeitos dos fármacos , Osseointegração/efeitos da radiação , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Fenômenos Biomecânicos/efeitos da radiação , Proteína Morfogenética Óssea 2/metabolismo , Bovinos , Hidroxiapatitas/farmacologia , Processamento de Imagem Assistida por Computador , Masculino , Ratos
16.
Braz Oral Res ; 34: e007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049108

RESUMO

The aim of this study was to assess the influence of cyclosporine administration on the repair of critical-sized calvaria defects (CSDs) in rat calvaria filled with diverse biomaterials. Sixty animals were divided into two groups: the control (CTR) group (saline solution) and the cyclosporine (CCP) group (cyclosporine, 10 mg/kg/day). These medications were administered daily by gavage, beginning 15 days before the surgical procedure and lasting until the day the animals were euthanized. A CSD (5 mm Ø) was made in the calvaria of each animal, which was allocated to one of 3 subgroups, according to the biomaterial used to fill the defect: coagulum (COA), deproteinized bovine bone (DBB), or biphasic calcium phosphate ceramics of hydroxyapatite and ß-phosphate tricalcium (HA/TCP). Euthanasia of the animals was performed 15 and 60 days after the surgical procedure (n = 5 animals/period/subgroup). Bone repair (formation) assessment was performed through microtomography and histometry, while the analyses of the expression of the BMP2, Osteocalcin, and TGFß1 proteins were performed using immunohistochemistry. The CSDs not filled with biomaterials demonstrated lower bone formation in the CCP group. At 15 days, less bone formation was observed in the CSDs filled with DBB, a smaller volume of mineralized tissue was observed in the CSDs filled with HA/TCP, and the expression levels of BMP2 and osteocalcin were lower in the CCP group compared to the CTR group. The use of cyclosporine impaired bone repair in CSD, and this effect can be partially explained by the suppression of BMP2 and osteocalcin expression.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Inibidores de Calcineurina/farmacologia , Ciclosporina/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/análise , Imuno-Histoquímica , Masculino , Osteocalcina/análise , Distribuição Aleatória , Ratos , Reprodutibilidade dos Testes , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , Fator de Crescimento Transformador beta1/análise , Microtomografia por Raio-X
17.
Cell Prolif ; 53(3): e12784, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32080957

RESUMO

OBJECTIVES: CD31hi EMCNhi vessels (CD31, also known as PECAM1 [platelet and endothelial cell adhesion molecule 1]; EMCN, endomucin), which are strongly positive for CD31 and endomucin, couple angiogenesis and osteogenesis. However, the role of CD31hi EMCNhi vessels in bone regeneration remains unknown. In the present study, we investigated the role of CD31hi EMCNhi vessels in the process of bone regeneration. MATERIALS AND METHODS: We used endothelial-specific Krüppel like factor 3 (Klf3) knockout mice and ophiopogonin D treatment to interfere with CD31hi EMCNhi vessel formation. We constructed a bone regeneration model by surgical ablation of the trabecular bone. Immunofluorescence and micro-computed tomography (CT) were used to detect CD31hi EMCNhi vessels and bone formation. RESULTS: CD31hi EMCNhi vessels participate in the process of bone regeneration, such that endothelial-specific Klf3 knockout mice showed increased CD31hi EMCNhi vessels and osteoprogenitors in the bone regeneration area, and further accelerated bone formation. We also demonstrated that the natural compound, ophiopogonin D, acts as a KLF3 inhibitor to promote vessels formation both in vitro and in vivo. Administration of ophiopogonin D increased the abundance of CD31hi Emcnhi vessels and accelerated bone healing. CONCLUSIONS: Our findings confirmed the important role of CD31hi Emcnhi vessels in bone regeneration and provided a new target to treat bone fracture or promote bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Saponinas/farmacologia , Sialoglicoproteínas/metabolismo , Espirostanos/farmacologia , Animais , Células Cultivadas , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteogênese/efeitos dos fármacos
18.
J Nanobiotechnology ; 18(1): 39, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32103765

RESUMO

BACKGROUND: The repair of large bone defects is a great challenge in clinical practice. In this study, copper-loaded-ZIF-8 nanoparticles and poly (lactide-co-glycolide) (PLGA) were combined to fabricate porous PLGA/Cu(I)@ZIF-8 scaffolds using three-dimensional printing technology for infected bone repair. METHODS: The surface morphology of PLGA/Cu(I)@ZIF-8 scaffolds was investigated by transmission electron microscopy and scanning electron microscopy. The PLGA/Cu(I)@ZIF-8 scaffolds were co-cultured with bacteria to determine their antibacterial properties, and with murine mesenchymal stem cells (MSCs) to explore their biocompatibility and osteoconductive properties. The bioactivity of the PLGA/Cu(I)@ZIF-8 scaffolds was evaluated by incubating in simulated body fluid. RESULTS: The results revealed that the PLGA/Cu(I)@ZIF-8 scaffolds had porosities of 80.04 ± 5.6% and exhibited good mechanical properties. When incubated with H2O2, Cu(I)@ZIF-8 nanoparticles resulted generated reactive oxygen species, which contributed to their antibacterial properties. The mMSCs cultured on the surface of PLGA/Cu(I)@ZIF-8 scaffolds were well-spread and adherent with a high proliferation rate, and staining with alkaline phosphatase and alizarin red was increased compared with the pure PLGA scaffolds. The mineralization assay showed an apatite-rich layer was formed on the surface of PLGA/Cu(I)@ZIF-8 scaffolds, while there was hardly any apatite on the surface of the PLGA scaffolds. Additionally, in vitro, Staphylococcus aureus cultured on the PLGA/Cu(I)@ZIF-8 scaffolds were almost all dead, while in vivo inflammatory cell infiltration and bacteria numbers were dramatically reduced in infected rats implanted with PLGA/Cu@ZIF-8 scaffolds. CONCLUSION: All these findings demonstrate that PLGA/Cu(I)@ZIF-8 scaffolds possess excellent antibacterial and osteoconductive properties, as well as good biocompatibility and high bioactivity. This study suggests that the PLGA/Cu(I)@ZIF-8 scaffolds could be used as a promising biomaterial for bone tissue engineering, especially for infected bone repair.


Assuntos
Antibacterianos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Nanocompostos/química , Impressão Tridimensional , Tecidos Suporte/química , Animais , Bactérias/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Adesão Celular , Peróxido de Hidrogênio , Células-Tronco Mesenquimais/metabolismo , Camundongos , Nanopartículas/química , Osteogênese , Porosidade , Engenharia Tecidual
20.
Plast Reconstr Surg ; 145(2): 337e-347e, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31985634

RESUMO

BACKGROUND: Three-dimensionally-printed bioceramic scaffolds composed of ß-tricalcium phosphate delivering the osteogenic agent dipyridamole can heal critically sized calvarial defects in skeletally mature translational models. However, this construct has yet to be applied to growing craniofacial models. In this study, the authors implanted three-dimensionally-printed bioceramic/dipyridamole scaffolds in a growing calvaria animal model and evaluated bone growth as a function of geometric scaffold design and dipyridamole concentration. Potential adverse effects on the growing suture were also evaluated. METHODS: Bilateral calvarial defects (10 mm) were created in 5-week-old (approximately 1.1 kg) New Zealand White rabbits (n = 16 analyzed). Three-dimensionally-printed bioceramic scaffolds were constructed in quadrant form composed of varying pore dimensions (220, 330, and 500 µm). Each scaffold was coated with collagen and soaked in varying concentrations of dipyridamole (100, 1000, and 10,000 µM). Controls consisted of empty defects. Animals were killed 8 weeks postoperatively. Calvariae were analyzed using micro-computed tomography, three-dimensional reconstruction, and nondecalcified histologic sectioning. RESULTS: Scaffold-induced bone growth was statistically greater than bone growth in empty defects (p = 0.02). Large scaffold pores, 500 µm, coated in 1000 µM dipyridamole yielded the most bone growth and lowest degree of scaffold presence within the defect. Histology showed vascularized woven and lamellar bone along with initial formation of vascular canals within the scaffold lattice. Micro-computed tomographic and histologic analysis revealed patent calvarial sutures without evidence of ectopic bone formation across all dipyridamole concentrations. CONCLUSION: The authors present an effective pediatric bone tissue-engineering scaffold design and dipyridamole concentration that is effective in augmentation of calvarial bone generation while preserving cranial suture patency.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/uso terapêutico , Dipiridamol/uso terapêutico , Fraturas Cranianas/cirurgia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Dipiridamol/administração & dosagem , Modelos Animais de Doenças , Coelhos , Crânio/efeitos dos fármacos , Crânio/lesões , Fraturas Cranianas/tratamento farmacológico
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