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1.
Int J Nanomedicine ; 14: 6019-6033, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534334

RESUMO

Objective: Icariin (IC) promotes osteogenic differentiation, and it may be a potential small molecule drug for local application in bone regeneration. Icariin-loaded hydroxyapatite/alginate (IC/HAA) porous composite scaffolds were designed in this study for the potential application of the sustainable release of icariin and subsequent bone regeneration. Methods: An icariin-loaded hydroxyapatite/alginate porous composite scaffold was prepared and characterized by SEM and HPLC for morphology and release behavior, respectively. The mechanical properties, degradation in PBS and cytotoxicity on BMSCs were also evaluated by MTT assay, compression strength and calculation of weight remaining ratio, respectively. Rabbit BMSCs were cocultured with IC/HAA scaffolds, and ALP activity and Alizarin Red staining were performed to evaluate osteogenic differentiation induction. The mRNA and protein expression level of an osteogenic gene was detected by RT-PCR and Western blotting, respectively. In vivo animal models of critical bone defects in the radius of rabbit were used. Four and 12 weeks after the implantation of IC/HAA scaffolds in the bone defect, radiographic images of the radius were obtained and scored by using the Lane and Sandhu X-ray scoring system. Tissue samples were also evaluated using H&E and Masson staining, and an osteogenic gene and Wnt signaling pathway genes were detected. Results: A hydroxyapatite/alginate (HAA) porous composite scaffold-loaded icariin was fabricated using a freeze-drying method. Our data indicated that the icariin was loaded in alginate scaffold without compromising the macro/microstructure or mechanical properties of the scaffold. Notably, the IC/HAA promoted the proliferation of rBMSCs without exerting cytotoxicity on rBMSCs. In vivo, rabbit radius bone defect experiments demonstrated that the IC/HAA scaffold exhibited better capacity for bone regeneration than HAA, and IC/HAA upregulated the relative expression levels of an osteogenic gene and the Wnt signaling pathway genes. Most notably, the IC/HAA scaffold also inhibited osteoclast activity in vivo. Conclusion: Our data suggests a promising application for the use of HAA scaffolds to load icariin and promote bone regeneration in situ through mediation of the coupling processes of osteogenesis induction and osteoclast activity inhibition.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Flavonoides/farmacologia , Osteoclastos/metabolismo , Osteogênese , Tecidos Suporte/química , Alginatos/farmacologia , Animais , Materiais Biocompatíveis/farmacologia , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Porosidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Rádio (Anatomia)/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(9): 1181-1189, 2019 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-31512463

RESUMO

Objective: To investigate the effect of icarin/attapulgite/collagen type Ⅰ/polycaprolactone (ICA/ATP/Col Ⅰ/PCL) composite scaffold in repair of rabbit tibia defect. Methods: The ICA/20%ATP/Col Ⅰ/PCL (scaffold 1), ICA/30%ATP/Col Ⅰ/PCL (scaffold 2), 20%ATP/Col Ⅰ/PCL (scaffold 3), and 30%ATP/Col Ⅰ/PCL (scaffold 4) composite scaffolds were constructed by solution casting-particle filtration method. The structure characteristics of the scaffold 2 before and after cross-linking were observed by scanning electron microscopy, and the surface contact angles of the scaffold 2 and the scaffold 4 were used to evaluate the water absorption performance of the material. The in vitro degradation test was used to evaluate the sustained-release effect of the scaffold 2. Thirty male Japanese white rabbits, weighing (2.0±0.1) kg, were randomly divided into groups A, B, C, D, and E, 6 in each group. After making a 1 cm- diameter bilateral tibial defects model, group A was the defect control group without any material implanted. Groups B, C, D, and E were implanted with scaffolds 3, 4, 1, and 2 at the defect sites, respectively. At 4, 8, and 12 weeks after operation, the repairing effects of 4 scaffolds were observed by gross observation, histological observation of HE and Masson staining, and immunohistochemical staining of osteogenic specific transcription factor (runt-related transcription factor 2, RUNX2), osteogenic related transcription factor [Osterix (OSX), Col Ⅰ, osteopontin (OPN)]. Results: Scanning electron microscopy observation showed that the scaffolds were all porous. The structure of the material was loose before and after cross-linking. The surface contact angle showed that the scaffold was hydrophobic, and the scaffold 2 was more hydrophobic than scaffold 4. The sustained-release effect in vitro showed that the drug could be released in a micro and long-term manner. In the animal implantation experiment, the gross observation showed that the defects were significantly smaller in groups D and E than in groups A, B, and C at 4 and 12 weeks after operation. HE and Masson staining showed that the defect of group A was full of connective tissue at 4 weeks after operation, a large number of fibers were seen in groups B and C, and the new bone formation was observed in groups D and E. The increase of new bone was observed in each group at 8 weeks after operation. The defect of group A was still dominated by connective tissue at 12 weeks after operation, and a small amount of new bone tissue was observed in groups B and C, and a large number of new bone tissue was observed in groups D and E, especially in group E, and most of the materials degraded. Immunohistochemical staining showed that the expressions of RUNX2 and OSX in the new tissues of groups D and E were significantly higher than those of the other groups at 4 weeks after operation. The expression of RUNX2 decreased at 8 and 12 weeks after operation. After 8 weeks and 12 weeks, the expressions of Col Ⅰand OPN increased than in 4 weeks. And the expressions of Col Ⅰ and OPN in the new tissues of groups D and E were significantly more than those of the other groups. Conclusion: ICA/ATP/Col I/PCL composite scaffolds have good porosity and biocompatibility, can promote bone formation, and have good bone regeneration and repair effect.


Assuntos
Colágeno Tipo I , Engenharia Tecidual , Tecidos Suporte , Animais , Flavonoides/química , Compostos de Magnésio/química , Masculino , Poliésteres/química , Coelhos , Distribuição Aleatória , Compostos de Silício/química , Tíbia/lesões , Engenharia Tecidual/métodos , Engenharia Tecidual/normas , Tecidos Suporte/química , Tecidos Suporte/normas
3.
Int J Nanomedicine ; 14: 5491-5502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31410000

RESUMO

Purpose: Meniscus is a fibrocartilagenous tissue that cannot effectively heal due to its complex structure and presence of avascular zone. Thus, tissue engineering and regenerative medicine offer an alternative for the regeneration of meniscus tissues using bioscaffolds as a replacement for the damaged one. The aim of this study was to prepare an ideal meniscus bioscaffold with minimal adverse effect on extracellular matrix components (ECMs) using a sonication treatment system. Methods: The decellularization was achieved using a developed closed sonication treatment system for 10 hrs, and continued with a washing process for 5 days. For the control, a simple immersion treatment was set as a benchmark to compare the decellularization efficiency. Histological and biochemical assays were conducted to investigate the cell removal and retention of the vital extracellular matrix. Surface ultrastructure of the prepared scaffolds was evaluated using scanning electron microscope at 5,000× magnification viewed from cross and longitudinal sections. In addition, the biomechanical properties were investigated through ball indentation testing to study the stiffness, residual forces and compression characteristics. Statistical significance between the samples was determined with p-value =0.05. Results: Histological and biochemical assays confirmed the elimination of antigenic cellular components with the retention of the vital extracellular matrix within the sonicated scaffolds. However, there was a significant removal of sulfated glycosaminoglycans. The surface histoarchitecture portrayed the preserved collagen fibril orientation and arrangement. However, there were minor disruptions on the structure, with few empty micropores formed which represented cell lacunae. The biomechanical properties of bioscaffolds showed the retention of viscoelastic behavior of the scaffolds which mimic native tissues. After immersion treatment, those scaffolds had poor results compared to the sonicated scaffolds due to the inefficiency of the treatment. Conclusion: In conclusion, this study reported that the closed sonication treatment system had high capabilities to prepare ideal bioscaffolds with excellent removal of cellular components, and retained extracellular matrix and biomechanical properties.


Assuntos
Menisco/citologia , Ortopedia , Sonicação/métodos , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Fenômenos Biomecânicos , Bovinos , Colágeno/metabolismo , Força Compressiva , Glicosaminoglicanos/metabolismo
4.
Int J Nanomedicine ; 14: 5753-5783, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413573

RESUMO

Tissue engineering embraces the potential of recreating and replacing defective body parts by advancements in the medical field. Being a biocompatible nanomaterial with outstanding physical, chemical, optical, and biological properties, graphene-based materials were successfully employed in creating the perfect scaffold for a range of organs, starting from the skin through to the brain. Investigations on 2D and 3D tissue culture scaffolds incorporated with graphene or its derivatives have revealed the capability of this carbon material in mimicking in vivo environment. The porous morphology, great surface area, selective permeability of gases, excellent mechanical strength, good thermal and electrical conductivity, good optical properties, and biodegradability enable graphene materials to be the best component for scaffold engineering. Along with the apt microenvironment, this material was found to be efficient in differentiating stem cells into specific cell types. Furthermore, the scope of graphene nanomaterials in liver tissue engineering as a promising biomaterial is also discussed. This review critically looks into the unlimited potential of graphene-based nanomaterials in future tissue engineering and regenerative therapy.


Assuntos
Grafite/química , Fígado/fisiologia , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Microambiente Celular , Humanos , Nanocompostos/química
5.
Life Sci ; 234: 116743, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31408660

RESUMO

AIMS: The present study aimed to investigate the mechanism of bone repair mediated by recombination BMP-2 (rhBMP-2)/recombination CXC chemokine ligand-13 (rhCXCL13)-loaded hollow hydroxyapatite (HA) microspheres/chitosan (CS) composite. MATERIALS AND METHODS: Firstly, the biological activity of rhBMP-2 and rhCXCL13 released from the complex was investigated. Secondly, the effect of rhBMP-2 sustained release solution on ALP activity and rhCXCL13 sustained release solution on cell migration of rat bone marrow mesenchyme stem cells was tested. Thirdly, osteoblasts differentiation test, X-ray scoring and three-point bending test were performed. Finally, the mRNAs expression of osteogenic marker genes and the protein expression of Runx2 was tested by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting (WB), respectively. KEY FINDINGS: RhBMP-2 could significantly promote the proliferation and differentiation, and RhCXCL13 could promote the migration of rat bone marrow MSCs. Detection of ALP activity and calcium salt deposition showed that rhBMP-2 and rhCXCL13 could significantly improve the biological activity and promote cell differentiation ability. X-ray scoring of radius and flexural strength test showed that rhBMP-2 and rhCXCL13 could promote bone healing and improve the bending resistance of bone tissue. The in vitro molecular experiments including RT-PCR and WB further demonstrated the roles of rhBMP-2 and rhCXCL13 in bone formation and bone repair. SIGNIFICANCE: Our results indicated that the hollow HA microspheres/CS composite could be effective as a delivery vehicle for rhBMP-2 and rhCXCL13 in bone regeneration and bone repair. In this process, rhBMP-2 may promote bone regeneration by regulating bone marrow MSCs cells recruited by rhCXCL13.


Assuntos
Proteína Morfogenética Óssea 2/administração & dosagem , Quimiocina CXCL13/administração & dosagem , Quitosana/análogos & derivados , Preparações de Ação Retardada/química , Durapatita/química , Osteogênese/efeitos dos fármacos , Tecidos Suporte/química , Fator de Crescimento Transformador beta/administração & dosagem , Animais , Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2/farmacologia , Regeneração Óssea/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL13/farmacologia , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Coelhos , Ratos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta/farmacologia
6.
Braz J Med Biol Res ; 52(8): e8318, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31411247

RESUMO

Currently, there is great clinical need for suitable synthetic grafts that can be used in vascular diseases. Synthetic grafts have been successfully used in medium and large arteries, however, their use in small diameter vessels is limited and presents a high failure rate. In this context, the aim of this study was to develop tissue engineering scaffolds, using poly(trimethylene carbonate-co-L-lactide) (PTMCLLA), for application as small diameter vascular grafts. For this, copolymers with varying trimethylene carbonate/lactide ratios - 20/80, 30/70, and 40/60 - were submitted to electrospinning and the resulting scaffolds were evaluated in terms of their physicochemical and biological properties. The scaffolds produced with PTMCLLA 20/80, 30/70, and 40/60 showed smooth fibers with an average diameter of 771±273, 606±242, and 697±232 nm, respectively. When the degradation ratio was evaluated, the three scaffold groups had a similar molecular weight (Mw) on the final day of analysis. PTMCLLA 30/70 and 40/60 scaffolds exhibited greater flexibility than the PTMCLLA 20/80. However, the PTMCLLA 40/60 scaffolds showed a large wrinkling and their biological properties were not evaluated. The PTMCLLA 30/70 scaffolds supported the adhesion and growth of mesenchymal stem cells (MSCs), endothelial progenitor cells, and smooth muscle cells (SMCs). In addition, they provided a spreading of MSCs and SMCs. Given the results, the electrospun scaffolds produced with PTMCLLA 30/70 copolymer can be considered promising candidates for future applications in vascular tissue engineering.


Assuntos
Prótese Vascular , Dioxanos/química , Poliésteres/química , Tecidos Suporte/química , Proliferação de Células , Células Cultivadas/citologia , Células Progenitoras Endoteliais/citologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Miócitos de Músculo Liso/citologia
7.
Biomater Sci ; 7(9): 3906-3917, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322163

RESUMO

Cardiovascular diseases represent a major socio-economic burden. In recent years, considerable effort has been invested in optimizing cell delivery strategies to advance cell transplantation therapies to restore heart function for example after an infarct. A particular issue is that the implantation of cells using a non-electroconductive matrix potentially causes arrhythmia. Here, we demonstrate that our hydrazide-functionalized nanotubes-pericardial matrix-derived electroconductive biohybrid hydrogel provides a suitable environment for maturation of human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes. hiPSC-derived cardiomyocytes exhibited an improved contraction amplitude (>500%) on conductive hydrogels compared to cells cultured on Matrigel®. This was accompanied by increased cellular alignment, enhanced connexin 43 expression, and improved sarcomere organization suggesting maturation of the hiPSC-derived cardiomyocytes. Sarcomeric length of these cells increased from 1.3 to 1.7 µm. Moreover, 3D cell-laden engineered tissues exhibited enhanced calcium handling as well as positive response to external electrical and pharmaceutical stimulation. Collectively, our data indicate that our biohybrid hydrogels consisting of solubilized nanostructured pericardial matrix and electroconductive positively charged hydrazide-conjugated carbon nanotubes provide a promising material for stem cell-based cardiac tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Nanotubos de Carbono/química , Pericárdio/química , Tecidos Suporte/química , Biomarcadores/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Colágeno/química , Conexina 43/metabolismo , Combinação de Medicamentos , Condutividade Elétrica , Humanos , Laminina/química , Células-Tronco Mesenquimais/citologia , Tamanho da Partícula , Proteoglicanas/química
8.
Int J Nanomedicine ; 14: 4261-4276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31289441

RESUMO

Purpose: In the field of small-caliber vascular scaffold research, excellent vascular remodeling is the key to ensuring anticoagulant function. We prepared an off-the-shelf bi-layered vascular scaffold with a dense inner layer and a loose outer layer and evaluated its remodeling capabilities by in vivo transplantation. Materials and Methods: Based on poly(L-lactide-co-ε-caprolactone) (PLCL), silk fibroin(SF), and heparin (Hep), PLCL/SF/Hep bi-layered scaffolds and PLCL/Hep bi-layered scaffolds were prepared by electrospinning. The inner layer was a PLCL/SF/Hep or PLCL/Hep nanofiber membrane, and the outer layer was PLCL/SF nano yarn. The in vitro tests included a hydrophilicity test, mechanical properties test, and blood and cell compatibility evaluation. The in vivo evaluation was conducted via single rabbit carotid artery replacement and subsequent examinations, including ultrasound imaging, immunoglobulin assays, and tissue section staining. Results: Compared to the PLCL/Hep nanofiber membrane, the hydrophilicity of the PLCL/SF/Hep nanofiber membrane was significantly improved. The mechanical strength met application requirements. Both the blood and cell compatibility were optimal. Most importantly, the PLCL/SF/Hep scaffolds maintained lumen patency for 3 months after carotid artery transplantation in live rabbits. At the same time, CD31 and α-SMA immunofluorescence staining confirmed bionic endothelial and smooth muscle layers remodeling. Conclusion: Using this hybrid strategy, PLCL and SF were combined to manufacture bi-layered small-caliber vascular scaffolds; these PLCL/SF/Hep scaffolds showed satisfactory vascular remodeling.


Assuntos
Fibroínas/química , Heparina/farmacocinética , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Artérias Carótidas , Proliferação de Células , Liberação Controlada de Fármacos , Heparina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Nanofibras/química , Adesividade Plaquetária , Próteses e Implantes , Coelhos
9.
Int J Nanomedicine ; 14: 4333-4351, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354264

RESUMO

Given the enormous increase in the risks of bone and cartilage defects with the rise in the aging population, the current treatments available are insufficient for handling this burden, and the supply of donor organs for transplantation is limited. Therefore, tissue engineering is a promising approach for treating such defects. Advances in materials research and high-tech optimized fabrication of scaffolds have increased the efficiency of tissue engineering. Electrospun nanofibrous scaffolds and hydrogel scaffolds mimic the native extracellular matrix of bone, providing a support for bone and cartilage tissue engineering by increasing cell viability, adhesion, propagation, and homing, and osteogenic isolation and differentiation, vascularization, host integration, and load bearing. The use of these scaffolds with advanced three- and four-dimensional printing technologies has enabled customized bone grafting. In this review, we discuss the different approaches used for cartilage and bone tissue engineering.


Assuntos
Osso e Ossos/fisiologia , Cartilagem/fisiologia , Nanopartículas/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Cartilagem/citologia , Matriz Extracelular/metabolismo , Humanos
10.
Cell Prolif ; 52(5): e12658, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31297910

RESUMO

OBJECTIVES: The bone tissue engineering primarily focuses on three-dimensional co-culture systems, which physical and biological properties resemble the cell matrix of actual tissues. The complex dialogue between bone-forming and endothelial cells (ECs) in a tissue-engineered construct will directly regulate angiogenesis and bone regeneration. The purpose of this study was to investigate whether co-culture between osteogenic and angiogenic cells derived by bone mesenchymal stem cells (MSCs) could affect cell activities and new bone formation. MATERIALS AND METHODS: Mesenchymal stem cells were dually induced to differentiate into osteogenic cells (OMSCs) and ECs; both cell types were co-cultured at different ratios to investigate their effects and underlying mechanisms through ELISA, RT-qPCR and MTT assays. The selected cell mixture was transplanted onto a nano-hydroxyapatite/polyurethane (n-HA/PU) scaffold to form a cell-scaffold construct that was implanted in the rat femoral condyles. Histology and micro-CT were examined for further verification. RESULTS: ELISA and gene expression studies revealed that co-cultured OMSCs/ECs (0.5/1.5) significantly elevated the transcription levels of osteogenic genes such as ALP, Col-I and OCN, as well as transcription factors Msx2, Runx2 and Osterix; it also upregulated angiogenic factors of vascular endothelial growth factor (VEGF) and CD31 when compared with cells cultured alone or in other ratios. The optimized OMSCs/ECs group had more abundant calcium phosphate crystal deposition, further facilitated their bone formation in vivo. CONCLUSIONS: The OMSCs/ECs-scaffold constructs at an optimal cell ratio (0.5/1.5) achieved enhanced osteogenic and angiogenic factor expression and biomineralization, which resulted in more effective bone formation.


Assuntos
Materiais Biomiméticos/química , Regeneração Óssea/fisiologia , Osso e Ossos/fisiologia , Células-Tronco Mesenquimais/citologia , Tecidos Suporte/química , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Durapatita/química , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Int J Nanomedicine ; 14: 3669-3678, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190818

RESUMO

Background: Electrospun gelatin/polycaprolactone (Gt/PCL) nanofibrous scaffolds loaded with graphene are novel nanomaterials with the uniquely strong property of electrical conductivity, which have been widely investigated for their potential applications in cardiovascular tissue engineering, including in bypass tracts for atrioventricular block. Purpose: Electrospun Gt/PCL/graphene nanofibrous mats were successfully produced. Scanning electron micrography showed that the fibers with graphene were smooth and homogeneous. In vitro, to determine the biocompatibility of the scaffolds, hybrid scaffolds with different fractions of graphene were seeded with neonatal rat ventricular myocytes. In vivo, Gt/PCL scaffolds with different concentrations of graphene were implanted into rats for 4, 8 and 12 weeks. Results: CCK-8 assays and histopathological staining (including DAPI, cTNT, and CX43) indicated that cells grew and survived well on the hybrid scaffolds if the mass fraction of graphene was lower than 0.5%. After implanting into rats for 4, 8 or 12 weeks, there was no gathering of inflammatory cells around the nanomaterials according to the HE staining results. Conclusion: The results indicate that Gt/PCL nanofibrous scaffolds loaded with graphene have favorable electrical conductivity and biological properties and may be suitable scaffolds for use in the treatment of atrioventricular block. These findings alleviate safety concerns and provide novel insights into the potential applications of Gt/PCL loaded with graphene, offering a solid foundation for comprehensive in vivo studies.


Assuntos
Gelatina/toxicidade , Grafite/toxicidade , Nanofibras/toxicidade , Poliésteres/toxicidade , Engenharia Tecidual , Tecidos Suporte/química , Testes de Toxicidade , Animais , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Processamento de Imagem Assistida por Computador , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ratos , Suínos
12.
Int J Nanomedicine ; 14: 3929-3941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213809

RESUMO

Introduction: Hierarchical nanofibrous scaffolds are emerging as a promising bone repair material due to their high cell adhesion activity and nutrient permeability. However, the existing method for hierarchical nanofibrous scaffolds fabrication is complicated and not perfectly suitable for further biomedical application in view of both structure and function. In this study, we constructed a hierarchical nanofibrous poly (l-lactic acid)/poly(ε-caprolactone) (PLLA/PCL) scaffold and further evaluated its bone healing ability. Methods: The hierarchical PLLA/PCL nanofibrous scaffold (PLLA/PCL) was prepared by one-pot TIPS and then rapidly mineralized at room temperature by an electrochemical deposition technique. After electrode-positioning at 2 V for 2 hrs, a scaffold coated with hydroxyapatite (M-PLLA/PCL) could be obtained. Results: The pore size of the M-PLLA/PCL scaffold was hierarchically distributed so as to match the biophysical structure for osteoblast growth. The M-PLLA/PCL scaffold showed better cell proliferation and osteogenesis activity compared to the PLLA/PCL scaffold. Further in vivo bone repair studies indicated that the M-PLLA/PCL scaffold could accelerate defect healing in 12 weeks. Conclusion: The results of this study implied that the as-prepared hydroxyapatite coated hierarchical PLLA/PCL nanofibrous scaffolds could be developed as a promising material for efficient bone tissue repair after carefully tuning the TIPS and electrodeposition parameters.


Assuntos
Regeneração Óssea/fisiologia , Galvanoplastia/métodos , Minerais/química , Nanofibras/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Eletricidade , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , Engenharia Tecidual/métodos , Microtomografia por Raio-X
13.
Carbohydr Polym ; 219: 210-218, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151519

RESUMO

Scaffold plays a critical role in stem cell differentiation and tissue regeneration. Composite scaffolds composed of bacterial cellulose (BC) and collagen (Col) in different ratios (1:1, 3:1, 5:1) were fabricated in this study. The composite scaffolds exhibit a well-organized interconnected porous structure, significantly better physical stability than Col scaffold, and more water uptake up to 400%. They were also favorable with cell attachment and growth. After osteogenic induction of umbilical cord blood derived mesenchymal stem cells (UCB-MSCs) for 3 weeks, we found more up-regulated osteogenic markers (collagen type 1, osteocalcin, bone sialoprotein) and significantly elevated proteins and calcium deposition, particularly with BC/Col (5:1) scaffold. When PKH-26 pre-labelled MSC-loaded scaffolds were subcutaneously transplanted in a mouse model, they showed many PKH-26-labelled cells and positive signals of α-smooth muscle actin, for neovascularization in the BC/Col (5:1). The current work demonstrates that our BC/Col composites may be promising as a bone tissue-engineered scaffold.


Assuntos
Celulose/química , Colágeno/química , Gluconacetobacter xylinus/metabolismo , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Celulose/uso terapêutico , Colágeno/uso terapêutico , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Osteogênese/efeitos dos fármacos
14.
Carbohydr Polym ; 220: 12-21, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196530

RESUMO

The assessment of several ink formulations for 3D printing based on two natural macromolecular compounds is presented. In the current research we have exploited the fast crosslinking potential of pectin and the remarkable shear-thinning properties of carboxylated cellulose nanofibrils, which is known to induce a desired viscoelastic behavior. Prior to 3D printing, the viscoelastic properties of the polysaccharide inks were evaluated by rheological measurements and injectability tests. The reliance of the printing parameters on the ink composition was established through one-dimensional lines printing, the base units of 3D-structures. The performance of the 3D-printed structures after ionic cross-linking was evaluated in terms of mechanical properties and rehydration behavior. MicroCT was also used to evaluate the morphology of the 3D-printed objects regarding the effect of pectin/nanocellulose ratio on the geometrical features of scaffolds. The proportionality between the two polymers proved to be the determining factor for the firmness and strength of the printed objects.


Assuntos
Celulose/análogos & derivados , Tinta , Nanofibras/química , Pectinas/química , Impressão Tridimensional , Materiais Biocompatíveis/química , Hidrogéis/química , Reologia , Engenharia Tecidual , Tecidos Suporte/química
16.
Int J Nanomedicine ; 14: 3331-3343, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31123401

RESUMO

Background and methods: A Cu-doped composite scaffold of nano calcium-deficient hydroxyapatite (n-CDHA)/multi(amino acid) copolymer (MAC) was prepared. The structure, porosity, morphology and compressive strength of the scaffolds were characterized, the in vitro degradability in phosphate-buffered solution (PBS) and cell responses to the scaffolds were investigated, and in vivo stimulation of bone formation were analyzed. Results: The scaffolds showed the compressive strength of approximately 12 MPa and total porosity of about 81%. Weight loss of the composite scaffolds was 63% after 16-week immersion in PBS. Cu release in scaffolds showed a marked dependence on the initial amount in the scaffolds over time. Cu-doped n-CDHA/MAC scaffolds with the content of Cu 0.5% and 1% in mass ratio showed better cell responses to proliferation and differentiation of rat bone marrow stromal cells (rBMSCs) than that with no Cu. After 12-week implantation in rabbits, 1% Cu-doped n-CDHA/MAC showed better ability of angiogenesis and osteogenesis compared to 0% Cu-doped n-CDHA/MAC. Conclusion: The 1% Cu-doped n-CDHA/MAC composite scaffold showed good capacity of angiogenesis and osteogenesis, and the Cu showed positive effects on cell growth and osteogenesis. And it has potential to be used as bone regeneration scaffolds.


Assuntos
Aminoácidos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osso e Ossos/fisiologia , Cobre/farmacologia , Durapatita/farmacologia , Nanopartículas/química , Polímeros/química , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Força Compressiva , Implantes Experimentais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Coelhos , Ratos , Microtomografia por Raio-X
17.
Carbohydr Polym ; 217: 152-159, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079672

RESUMO

Composite biomaterials offer a new approach for engineering novel, minimally-invasive scaffolds with properties that can be modified for a range of soft tissue applications. In this study, a new way of controlling the gelation of alginate hydrogels using Ga-based glass particles is presented. Through a comprehensive analysis, it was shown that the setting time, mechanical strength, stiffness and degradation properties of this composite can all be tailored for various applications. Specifically, the hydrogel generated through using a glass particle, wherein toxic aluminium is replaced with biocompatible gallium, exhibited enhanced properties. The material's stiffness matches that of soft tissues, while it displays a slow and tuneable gelation rate, making it a suitable candidate for minimally-invasive intra-vascular injection. In addition, it was also found that this composite can be tailored to deliver ions into the local cellular environment without affecting platelet adhesion or compromising viability of vascular cells in vitro.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Gálio/química , Vidro/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Alginatos/isolamento & purificação , Alginatos/toxicidade , Animais , Aorta/citologia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Módulo de Elasticidade , Células Endoteliais/efeitos dos fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Hidrogel de Polietilenoglicol-Dimetacrilato/toxicidade , Miócitos de Músculo Liso/efeitos dos fármacos , Engenharia Tecidual/métodos , Tecidos Suporte/química
18.
Bioelectrochemistry ; 129: 90-99, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31132529

RESUMO

A dual magnetic-pH-sensitive hydrogel-based scaffold was studied for optimization of a cell microenvironment by scaffold mechanical deformation and its biochemical response. In particular, the positions of the seeding cells and the concentration of potassium (K+) within the scaffold were optimized by a multieffect-coupling magnetic-pH-stimuli (MECmpH) model based on (i) the threshold of the mechanical force required for a mechanotransduction effect at the cellular level, and (ii) the common biological requirement for cell growth. In this model, the physicochemical mechanisms of a magnetic hydrogel were characterized using magneto-chemo-electro-mechanical coupled effects, including hydrogel magnetization, diffusion of the solvent and ions, ionic polarization, and nonlinear deformation. After validation of the model with experimental data, it was found that a higher pH and current intensity at the electromagnet and a shorter hydrogel-magnet distance contribute to larger scaffold deformation and thus a stronger mechanical force on the cells. Moreover, the cell seeding positions within the magnetic scaffold were optimized for improved cell culture through controlled current intensity in the electromagnet. Furthermore, the physiological concentration of K+ was also optimized by the initial fixed charge density within the scaffold. We concluded that this optimized magnetic scaffold via the MECmpH model may provide an appropriate microenvironment for efficient cell growth.


Assuntos
Microambiente Celular , Hidrogéis/química , Imãs/química , Tecidos Suporte/química , Fenômenos Biomecânicos , Módulo de Elasticidade , Humanos , Concentração de Íons de Hidrogênio , Campos Magnéticos , Mecanotransdução Celular , Modelos Biológicos , Modelos Químicos , Potássio/química
20.
Artif Cells Nanomed Biotechnol ; 47(1): 1710-1721, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31062604

RESUMO

A dual-layer biomimetic cartilage scaffold was prepared by mimicking the structural design, chemical cues and mechanical characteristics of mature articular cartilage. The surface layer was made from collagen (COL), chitosan (CS) and hyaluronic acid sodium (HAS). The transitional layer with microtubule array structure was prepared with COL, CS and silk fibroin (SF). The PLAG microspheres containing kartogenin (KGN) and the polylysine-heparin sodium nanoparticles containing TGF-ß1 (TPHNs) were constructed for the surface, transitional layer, respectively. The SEM result showed that the dual-layer composite scaffold had a double structure similar to natural cartilage. The vitro biocompatibility experiment showed that the biomimetic cartilage scaffold with orientated porous structure was more conducive to the proliferation and adhesion of BMSCs. A rabbit KOA cartilage defect model was established and biomimetic cartilage scaffolds were implanted in the defect area. Compared with the surface layer and transitional layer scaffolds group, the results of dual-layer biomimetic cartilage scaffold group showed that the defects had been completely filled, the boundary between new cartilage and surrounding tissue was difficult to identify, and the morphology of cells in repair tissue was almost in accordance with the normal cartilage after 16 weeks. All those results indicated that the biomimetic cartilage scaffold could effectively repair the defect of KOA, which is related to the fact that the scaffold could guide the morphology, orientation, and proliferation and differentiation of BMSCs. This work could potentially lead to the development of multilayer scaffolds mimicking the zonal organization of articular cartilage.


Assuntos
Materiais Biomiméticos/farmacologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/patologia , Osteoartrite do Joelho/patologia , Tecidos Suporte/química , Animais , Materiais Biomiméticos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Colágeno/química , Fibroínas/química , Ácido Hialurônico/química , Masculino , Fenômenos Mecânicos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Porosidade , Coelhos , Propriedades de Superfície
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