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1.
Methods Mol Biol ; 2206: 193-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32754819

RESUMO

The capability of forming functional blood vessel networks is critical for the characterization of endothelial cells. In this chapter, we will review a modified in vivo vascular network forming assay by replacing traditional mouse tumor-derived Matrigel with a well-defined collagen-fibrin hydrogel. The assay is reliable and does not require special equipment, surgical procedure, or a skilled person to perform. Moreover, investigators can modify this method on-demand for testing different cell sources, perturbation of gene functions, growth factors, and pharmaceutical molecules, and for the development and investigation of strategies to enhance neovascularization of engineered human tissues and organs.

2.
Biomater Sci ; 8(9): 2627-2637, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32242197

RESUMO

Various strategies have been explored to stimulate new bone formation. These strategies include using angiogenic stimulants in combination with inorganic biomaterials. Neovascularization during the neo-bone formation provides nutrients along with bone-forming minerals. Therefore, it is crucial to design a bone stimulating microenvironment composed of both pro-angiogenic and osteogenic factors. In this respect, human vascular endothelial growth factor (hVEGF) has been shown to promote blood vessel formation and bone formation. Furthermore, in recent years, whitlockite (WH), a novel phase of magnesium-containing calcium phosphate derivatives that exist in our bone tissue, has been synthesized and applied in bone tissue engineering. In this study, our aim is to explore the potential use of hVEGF and WH for bone tissue engineering. Our study demonstrated that hVEGF and a WH microenvironment synergistically stimulated osteogenic commitment of mesenchymal stem cells both in vitro and in vivo.

3.
Biomater Res ; 22: 1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29308274

RESUMO

Background: Tissue engineering is an interdisciplinary field that attempts to restore or regenerate tissues and organs through biomimetic fabrication of scaffolds with specific functionality. In recent years, graphene oxide (GO) is considered as promising biomaterial due to its nontoxicity, high dispersity, and hydrophilic interaction, and these characteristics are key to stimulating the interactions between substrates and cells. Method: In this study, GO substrates were fabricated via chemically immobilizing GO at 1.0 mg/ml on glass slides. Furthermore, we examined the osteogenic responses of murine mesenchymal-like stem cells, C3H10T1/2 cells, on GO substrates. Results: C3H10T1/2 cells on GO substrates resulted in increased cell surface area, enhanced cellular adhesions, and instigated osteogenic differentiation. Furthermore, priming of C3H10T1/2 cells with chondrocyte-conditioned medium (CM) could further induce a synergistic effect of osteogenesis on GO substrates. Conclusions: All of these data suggest that GO substrate along with CM is suitable for upregulating osteogenic responses of mesenchymal stem cells.

4.
Int J Biol Macromol ; 110: 479-487, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29229249

RESUMO

Meniscus tissues have limited regenerative capacity once damaged. The treatment options for the meniscus tissue regeneration have been limited to arthroscopic meniscectomy or surgical interventions. The injectable hydrogels based system would provide an alternative to the conventional meniscus therapy by providing a minimally invasive treatment alternative. Here we utilized enzyme-based approaches to fabricate tissue adhesive hydrogels for meniscus repair. Tyramine (TA) conjugated hyaluronic acid (TA-HA) and gelatin are susceptible to tyrosinase (TYR)-mediated crosslinking in vitro and in vivo. Importantly, mechanical properties and degradation kinetics are modulated by the TA substitution and TYR concentrations. In addition, TYR -mediated crosslinking displayed tissue-adhesive properties. Furthermore, fibrochondrocyte-laden and TYR-crosslinked hydrogels demonstrated strong biocompatibility and resulted in enhancement of cartilage-specific gene expression and matrix synthesis. Overall, this represents a potential application of enzyme-mediated crosslinking hydrogels for meniscus tissue engineering.


Assuntos
Hidrogéis , Menisco , Adesivos Teciduais , Animais , Ácido Hialurônico/química , Ácido Hialurônico/farmacocinética , Ácido Hialurônico/farmacologia , Hidrogéis/química , Hidrogéis/farmacocinética , Hidrogéis/farmacologia , Menisco/metabolismo , Menisco/cirurgia , Coelhos , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Tiramina/química , Tiramina/farmacocinética , Tiramina/farmacologia
5.
J Am Chem Soc ; 140(4): 1199-1202, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29281277

RESUMO

Cell surface modification has been extensively studied to enhance the efficacy of cell therapy. Still, general accessibility and versatility are remaining challenges to meet the increasing demand for cell-based therapy. Herein, we present a facile and universal cell surface modification method that involves mild reduction of disulfide bonds in cell membrane protein to thiol groups. The reduced cells are successfully coated with biomolecules, polymers, and nanoparticles for an assortment of applications, including rapid cell assembly, in vivo cell monitoring, and localized cell-based drug delivery. No adverse effect on cellular morphology, viability, proliferation, and metabolism is observed. Furthermore, simultaneous coating with polyethylene glycol and dexamethasone-loaded nanoparticles facilitates enhanced cellular activities in mice, overcoming immune rejection.


Assuntos
Membrana Celular/química , Dissulfetos/química , Animais , Comunicação Celular , Linhagem Celular , Sobrevivência Celular , Dexametasona/química , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Camundongos , Camundongos Nus , Nanopartículas/química , Oxirredução , Polietilenoglicóis/química
6.
Adv Healthc Mater ; 6(23)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29171714

RESUMO

Various strategies have been explored to overcome critically sized bone defects via bone tissue engineering approaches that incorporate biomimetic scaffolds. Biomimetic scaffolds may provide a novel platform for phenotypically stable tissue formation and stem cell differentiation. In recent years, osteoinductive and inorganic biomimetic scaffold materials have been optimized to offer an osteo-friendly microenvironment for the osteogenic commitment of stem cells. Furthermore, scaffold structures with a microarchitecture design similar to native bone tissue are necessary for successful bone tissue regeneration. For this reason, various methods for fabricating 3D porous structures have been developed. Innovative techniques, such as 3D printing methods, are currently being utilized for optimal host stem cell infiltration, vascularization, nutrient transfer, and stem cell differentiation. In this progress report, biomimetic materials and fabrication approaches that are currently being utilized for biomimetic scaffold design are reviewed.


Assuntos
Materiais Biomiméticos/química , Osso e Ossos/metabolismo , Nicho de Células-Tronco , Células-Tronco/metabolismo , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Osso e Ossos/citologia , Diferenciação Celular , Humanos , Porosidade , Células-Tronco/citologia
7.
ACS Appl Mater Interfaces ; 9(26): 21639-21650, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28605908

RESUMO

Chondroitin sulfate (CS) is the major component of glycosaminoglycan in connective tissue. In this study, we fabricated methacrylated PEGDA/CS-based hydrogels with varying CS concentration (0, 1, 5, and 10%) and investigated them as biomineralizing three-dimensional scaffolds for charged ion binding and depositions. Due to its negative charge from the sulfate group, CS exhibited an osteogenically favorable microenvironment by binding charged ions such as calcium and phosphate. Particularly, ion binding and distribution within negatively charged hydrogel was dependent on CS concentration. Furthermore, CS dependent biomineralizing microenvironment induced osteogenic differentiation of human tonsil-derived mesenchymal stem cells in vitro. Finally, when we transplanted PEGDA/CS-based hydrogel into a critical sized cranial defect model for 8 weeks, 10% CS hydrogel induced effective bone formation with highest bone mineral density. This PEGDA/CS-based biomineralizing hydrogel platform can be utilized for in situ bone formation in addition to being an investigational tool for in vivo bone mineralization and resorption mechanisms.


Assuntos
Sulfatos de Condroitina/química , Osso e Ossos , Diferenciação Celular , Células Cultivadas , Humanos , Hidrogéis , Células-Tronco Mesenquimais , Osteogênese , Engenharia Tecidual , Tecidos Suporte
8.
J Mech Behav Biomed Mater ; 71: 184-191, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28342326

RESUMO

The mandibular condyle consists of articular cartilage and subchondral bone that play an important role in bearing loads at the temporomandibular joint (TMJ) during static occlusion and dynamic mastication. The objective of the current study was to examine effects of sex and cartilage on 1) static and dynamic mechanical analysis (DMA) based dynamic energy storage and dissipation for the cartilage-subchondral bone construct of the human mandibular condyle, and 2) their correlations with the tissue mineral density and trabecular morphological parameters of subchondral bone. Cartilage-subchondral bone constructs were obtained from 16 individual human cadavers (9 males, 7 females, 79.00±13.10 years). After scanning with micro-computed tomography, the specimens were subjected to a non-destructive compressive static loading up to 7N and DMA using a cyclic loading profile (-5±2N at 2Hz). After removing the cartilage from the same specimen, the series of loading experiments were repeated. Static stiffness (K) and energy dissipation (W), and dynamic storage (K'), loss (K'') stiffness, and energy dissipation (tan δ) were assessed. Gray values, which are proportional to degree of bone mineralization, and trabecular morphological parameters of the subchondral bone were also measured. After removal of the cartilage, static energy dissipation significantly decreased (p<0.009) but dynamic energy dissipation was not influenced (p>0.064). Many subchondral bone properties were significantly correlated with the overall mechanical behavior of the cartilage-subchondral bone constructs for males (p<0.047) but not females (p>0.054). However, after removal of cartilage from the constructs, all of the significant correlations were no longer found (p>0.057). The current findings indicate that the subchondral bone is responsible for bearing static and dynamic loading in males but not in females. This result indicates that the female condyle may have a mechanically disadvantageous TMJ loading environment.


Assuntos
Côndilo Mandibular/fisiologia , Caracteres Sexuais , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cartilagem Articular/fisiologia , Feminino , Humanos , Masculino , Mastigação , Articulação Temporomandibular/fisiologia , Microtomografia por Raio-X
9.
Polymers (Basel) ; 9(12)2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30965950

RESUMO

Articular cartilage has a very limited regeneration capacity. Therefore, injury or degeneration of articular cartilage results in an inferior mechanical stability, load-bearing capacity, and lubrication capability. Here, we developed a biomimetic scaffold consisting of macroporous polyvinyl alcohol (PVA) sponges as a platform material for the incorporation of cell-embedded photocrosslinkable poly(ethylene glycol) diacrylate (PEGDA), PEGDA-methacrylated chondroitin sulfate (PEGDA-MeCS; PCS), or PEGDA-methacrylated hyaluronic acid (PEGDA-MeHA; PHA) within its pores to improve in vitro chondrocyte functions and subsequent in vivo ectopic cartilage tissue formation. Our findings demonstrated that chondrocytes encapsulated in PCS or PHA and loaded into macroporous PVA hybrid scaffolds maintained their physiological phenotypes during in vitro culture, as shown by the upregulation of various chondrogenic genes. Further, the cell-secreted extracellular matrix (ECM) improved the mechanical properties of the PVA-PCS and PVA-PHA hybrid scaffolds by 83.30% and 73.76%, respectively, compared to their acellular counterparts. After subcutaneous transplantation in vivo, chondrocytes on both PVA-PCS and PVA-PHA hybrid scaffolds significantly promoted ectopic cartilage tissue formation, which was confirmed by detecting cells positively stained with Safranin-O and for type II collagen. Consequently, the mechanical properties of the hybrid scaffolds were biomimetically reinforced by 80.53% and 210.74%, respectively, compared to their acellular counterparts. By enabling the recapitulation of biomimetically relevant structural and functional properties of articular cartilage and the regulation of in vivo mechanical reinforcement mediated by cell⁻matrix interactions, this biomimetic material offers an opportunity to control the desired mechanical properties of cell-laden scaffolds for cartilage tissue regeneration.

10.
Biomaterials ; 112: 31-43, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27744219

RESUMO

Bone remodeling process relies on complex signaling pathway between osteoblasts and osteoclasts and control mechanisms to achieve homeostasis of their growth and differentiation. Despite previous achievements in understanding complicated signaling pathways between cells and bone extracellular matrices during bone remodeling process, a role of local ionic concentration remains to be elucidated. Here, we demonstrate that synthetic whitlockite (WH: Ca18Mg2(HPO4)2(PO4)12) nanoparticles can recapitulate early-stage of bone regeneration through stimulating osteogenic differentiation, prohibiting osteoclastic activity, and transforming into mechanically enhanced hydroxyapatite (HAP)-neo bone tissues by continuous supply of PO43- and Mg2+ under physiological conditions. In addition, based on their structural analysis, the dynamic phase transformation from WH into HAP contributed as a key factor for rapid bone regeneration with denser hierarchical neo-bone structure. Our findings suggest a groundbreaking concept of 'living bone minerals' that actively communicate with the surrounding system to induce self-healing, while previous notions about bone minerals have been limited to passive products of cellular mineralization.


Assuntos
Materiais Biomiméticos/administração & dosagem , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Fosfatos de Cálcio/administração & dosagem , Fosfatos de Cálcio/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Materiais Biomiméticos/síntese química , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/fisiologia , Células Cultivadas , Humanos , Teste de Materiais , Nanopartículas/ultraestrutura , Tamanho da Partícula
11.
Int J Biol Macromol ; 93(Pt B): 1410-1419, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27185069

RESUMO

In this study, we investigated various highly porous extracellular matrix (ECM)-based cryogels for cartilage tissue engineering. For the fabrication of ECM-based cryogels, either methacrylated chondroitin sulfate (MeCS) or methacrylated hyaluronic acid (MeHA) were cross-linked along with poly (ethylene glycol) diacrylates (PEGDA) via free radical polymerization under freezing conditions. This procedure induces ice crystallization (used as a porogen) prior polymer crosslinking in which, after complete cryopolymerization, a thawing process transforms the ice crystals into a unique interconnected macroporous structure within ECM-cryogels. The developed ECM-cryogels exhibited an average macroporosity of 75% and supported the infiltration of chondrocyteds. When rabbit chondrocytes were cultured on ECM-cryogels, MeCS-based cryogels stimulated aggrecan gene expression and GAG accumulation, whereas MeHA-based cryogels stimulated type II collagen gene expression and collagen accumulation. These results demonstrate that design of ECM-based cryogels can play an important role in promoting specific ECM proteins secretion for cartilage tissue engineering.


Assuntos
Criogéis/química , Matriz Extracelular/química , Tecidos Suporte/química , Animais , Cartilagem Articular/citologia , Cartilagem Articular/fisiologia , Sobrevivência Celular , Células Cultivadas , Condrócitos/fisiologia , Feminino , Implantes Experimentais , Camundongos Endogâmicos BALB C , Camundongos Nus , Porosidade , Regeneração , Medicina Regenerativa , Engenharia Tecidual
12.
Acta Biomater ; 34: 21-29, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26884279

RESUMO

UNLABELLED: Stem cells have unique ability to undergo self-renewal indefinitely in culture and potential to differentiate into almost all cell types in the human body. However, the developing a method for efficiently differentiating or manipulating these stem cells for therapeutic purposes remains a challenging problem. Pluripotent stem cells, as well as adult stem cells, require biological cues for their proliferation and differentiation. These cues are largely controlled by cell-cell, cell-insoluble factors (such as extracellular matrix), and cell-soluble factors (such as cytokine or growth factors) interactions. In this review, we describe a state of research on various stem cell-based tissue engineering applications and high throughput strategies for developing synthetic or biosynthetic microenvironments to allow efficient commitments in stem cells. STATEMENT OF SIGNIFICANCE: Nowadays, pluripotency of stem cells have received much attention to use therapeutic purpose. However, a major difficulty with stem cell therapy is to control its differentiation through desired cells or tissues. In other words, various microenvironment factors are involved during stem cell differentiation, including dimensionality, growth factors, cell junctions, nutritional status, matrix stiffness, matrix composition, mechanical stress, and cell-matrix adhesion. Therefore, researchers have engineered a variety of platforms to enable controlling and monitoring bioactive factors to induce stem cell commitment. In this review, we report on recent advancements in a novel technology based on high-throughput strategies for stem cell-based tissue engineering applications.


Assuntos
Diferenciação Celular , Ensaios de Triagem em Larga Escala/métodos , Células-Tronco/citologia , Animais , Junções Célula-Matriz/metabolismo , Matriz Extracelular/metabolismo , Humanos , Engenharia Tecidual
13.
Drug Deliv Transl Res ; 6(2): 148-58, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25809935

RESUMO

A meniscus tear is a common knee injury, but its regeneration remains a clinical challenge. Recently, collagen-based scaffolds have been applied in meniscus tissue engineering. Despite its prevalence, application of natural collagen scaffold in clinical setting is limited due to its extremely low stiffness and rapid degradation. The purpose of the present study was to increase the mechanical properties and delay degradation rate of a collagen-based scaffold by photo-crosslinking using riboflavin (RF) and UV exposure. RF is a biocompatible vitamin B2 that showed minimal cytotoxicity compared to conventionally utilized photo-initiator. Furthermore, collagen photo-crosslinking with RF improved mechanical properties and delayed enzyme-triggered degradation of collagen scaffolds. RF-induced photo-crosslinked collagen scaffolds encapsulated with fibrochondrocytes resulted in reduced scaffold contraction and enhanced gene expression levels for the collagen II and aggrecan. Additionally, hyaluronic acid (HA) incorporation into photo-crosslinked collagen scaffold showed an increase in its retention. Based on these results, we demonstrate that photo-crosslinked collagen-HA hydrogels can be potentially applied in the scaffold-based meniscus tissue engineering.


Assuntos
Condrócitos/efeitos dos fármacos , Colágeno/efeitos dos fármacos , Menisco/citologia , Fármacos Fotossensibilizantes/farmacologia , Riboflavina/farmacologia , Engenharia Tecidual/métodos , Animais , Células Cultivadas , Reagentes para Ligações Cruzadas , Humanos , Ácido Hialurônico/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Teste de Materiais , Coelhos , Tecidos Suporte
14.
Adv Healthc Mater ; 5(1): 128-36, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25963732

RESUMO

Biomimicking ceramics have been developed to induce efficient recovery of damaged hard tissues. Among them, calcium phosphate-based bioceramics have been the most widely used because of their similar composition with human hard tissue and excellent biocompatibilities. However, the incomplete understanding of entire inorganic phases in natural bone has limited the recreation of complete bone compositions. In this work, broad biomedical evaluation of whitlockite (WH: Ca18Mg2(HPO4)2(PO4)12), which is the secondary inorganic phase in bone, is conducted to better understand human hard tissue and to seek potential application as a biomaterial. Based on the recently developed gram-scale method for synthesizing WH nanoparticles, the properties of WH as a material for cellular scaffolding and bone implants are assessed and compared to those of hydroxyapatite (HAP: Ca10(PO4)6(OH)2) and ß-tricalcium phosphate (ß-TCP: ß-Ca3(PO4)2). WH-reinforced composite scaffolds facilitate bone-specific differentiation compared to HAP-reinforced composite scaffolds. Additionally, WH implants induce similar or better bone regeneration in calvarial defects in a rat model compared to HAP and ß-TCP implants, with intermediate resorbability. New findings of the properties of WH that distinguish it from HAP and ß-TCP are significant in understanding human hard tissue, mimicking bone tissue at the nanoscale and designing functional bioceramics.


Assuntos
Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Durapatita/farmacologia , Teste de Materiais/métodos , Animais , Regeneração Óssea/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Dureza , Humanos , Implantes Experimentais , Masculino , Camundongos , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Tecidos Suporte/química , Dente/química , Água , Cicatrização/efeitos dos fármacos , Microtomografia por Raio-X
15.
J Biomed Nanotechnol ; 12(10): 1916-28, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29360334

RESUMO

Construction of 3-dimensional (3-D) engineered tissue is increasingly being investigated for use in drug discovery and regenerative medicine. Here, we developed multi-layered 3-D cellular assembly by using magnetic nanoparticles (MNP) isolated from Magnetospirillum sp. AMB-1 magnetotactic bacteria. Magnetized human dermal fibroblasts (HDFBs) were prepared by treatment with the MNP, induced to form 3-D assembly under a magnetic field. Analyses including LIVE/DEAD assay, transmission electron microscopy revealed that the MNP were internalized via clathrin-mediated endocytosis without cytotoxicity. The magnetized HDFBs could build 3-D structure as a function of seeding density. When the highest seeding density (5 × 105 cells/mm2 was used, the thickness of assembly was 41.90 ± 1.69 µm, with approximately 9.3 ± 1.6 cell layers being formed. Immunofluorescence staining confirmed homogeneous distribution of ECM and junction proteins throughout the 3-D assembly. Real-time PCR analysis showed decrease in expression levels of collagen types I and IV but increase in that of connexin 43 in the 3-D assembly compared with the 2-D culture. Finally, we demonstrated that the discernible layers can be formed hierarchically by serial assembly. In conclusion, our study showed that a multi-layered structure can be easily prepared using magnetically-assisted cellular assembly with highlighting cell-cell and cell-ECM communication.


Assuntos
Técnicas de Cultura de Células/métodos , Matriz Extracelular/metabolismo , Nanopartículas de Magnetita/química , Engenharia Tecidual/métodos , Células Cultivadas , Endocitose , Matriz Extracelular/química , Fibroblastos/química , Fibroblastos/metabolismo , Humanos , Campos Magnéticos , Modelos Biológicos
16.
Acta Biomater ; 25: 76-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26216508

RESUMO

UNLABELLED: Formyl peptide receptor-2 (FPR-2) is expressed in various cell types, such as phagocytes, fibroblasts, and endothelial cells. FPR-2 has been reported to play a significant role in inflammation and angiogenic response, and synthetic WKYMVm peptide has been identified as a novel peptide agonist for the FPR-2. In this study, we demonstrate that WKYMVm peptides stimulate the angiogenic potential of outgrowth endothelial cells (OECs). Upon WKYMVm peptide exposure, migration and proliferation of OECs were stimulated. WKYMVm effectively stimulated angiogenesis in tube formation assay and aortic ring assay. Furthermore, we fabricated injectable poly (lactide-co-glycolide) (PLGA) microspheres encapsulating WKYMVm peptides, which showed sustained release of cargo molecule. When WKYMVm peptide encapsulated microspheres were injected into the hind limb ischemia model, a single injection of microspheres was as effective as multiple injections of WKYMVm peptide in restoring blood flow from ischemic injury and promoting capillary growth. These results demonstrate that sustained release of WKYMVm peptide from microspheres in the application to ischemic hind limb extended angiogenic stimulation. STATEMENT OF SIGNIFICANCE: Formyl peptide receptor (FPR) has been reported to play an important role in inflammation and angiogenic response. A synthetic WKYMVm peptide has been identified as a novel peptide activating the FPR-2 that is expressed in a various cell types, such as phagocytes, fibroblasts, and endothelial cells. In this manuscript we explored a unique property of high-affinity ligand for formyl peptide receptors-2 (FPR-2) (i.e., WKYMVm). WKYMVm-induced activation of FPR2 has been reported to be crucial in host defense and inflammation by activation of phagocytes, monocytes, and lymphocytes. In this study, highlight the efficacy of WKYMVm peptide's role in inducing neovascularization in vivo hind limb ischemia model when the peptide was released from injected PLGA microspheres in sustained manner. Our results demonstrate that sustained release of WKYMVm peptide from microspheres have extended angiogenic stimulation capacity.


Assuntos
Ácido Láctico/química , Microesferas , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos/farmacologia , Ácido Poliglicólico/química , Animais , Aorta/fisiologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Emulsões , Regulação da Expressão Gênica/efeitos dos fármacos , Membro Posterior/irrigação sanguínea , Humanos , Técnicas In Vitro , Injeções , Isquemia/patologia , Salvamento de Membro , Masculino , Camundongos Endogâmicos BALB C , Neovascularização Fisiológica/genética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
17.
Adv Healthc Mater ; 4(9): 1339-47, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-25846518

RESUMO

Chondrogenic commitments of mesenchymal stem cells (MSCs) require 3D cellular organization. Furthermore, recent progresses in bioreactor technology have contributed to the development of various biophysical stimulation platforms for efficient cartilage tissue formation. Here, an approach is reported to drive 3D cellular organization and enhance chondrogenic commitment of bone-marrow-derived human mesenchymal stem cells (BM-hMSCs) via magnetic nanoparticle (MNP)-mediated physical stimuli. MNPs isolated from Magnetospirillum sp. AMB-1 are endocytosed by the BM-hMSCs in a highly efficient manner. MNPs-incorporated BM-hMSCs are pelleted and then subjected to static magnetic field and/or magnet-derived shear stress. Magnetic-based stimuli enhance level of sulfated glycosaminoglycan (sGAG) and collagen synthesis, and facilitate the chondrogenic differentiation of BM-hMSCs. In addition, both static magnetic field and magnet-derived shear stress applied for the chondrogenic differentiation of BM-hMSCs do not show increament of hypertrophic differentiation. This MNP-mediated physical stimulation platform demonstrates a promising strategy for efficient cartilage tissue engineering.


Assuntos
Diferenciação Celular , Condrócitos/metabolismo , Condrogênese , Campos Magnéticos , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/metabolismo , Condrócitos/citologia , Humanos , Magnetospirillum/química , Células-Tronco Mesenquimais/citologia , Resistência ao Cisalhamento
18.
Tissue Eng Part A ; 21(3-4): 757-66, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25266634

RESUMO

Articular cartilage damage is a persistent and increasing problem with the aging population. Strategies to achieve complete repair or functional restoration remain a challenge. Photopolymerizing-based hydrogels have long received an attention in the cartilage tissue engineering, due to their unique bioactivities, flexible method of synthesis, range of constituents, and desirable physical characteristics. In the present study, we have introduced unique bioactivity within the photopolymerizing-based hydrogels by copolymerizing polyethylene glycol (PEG) macromers with methacrylated extracellular matrix (ECM) molecules (hyaluronic acid and chondroitin sulfate [CS]) and integrin binding peptides (RGD peptide). Results indicate that cellular morphology, as observed by the actin cytoskeleton structures, was strongly dependent on the type of ECM component as well as the presence of integrin binding moieties. Further, CS-based hydrogel with integrin binding RGD moieties increased the lubricin (or known as superficial zone protein [SZP]) gene expression of the encapsulated chondrocytes. Additionally, CS-based hydrogel displayed cell-responsive degradation and resulted in increased DNA, GAG, and collagen accumulation compared with other hydrogels. This study demonstrates that integrin-mediated interactions within CS microenvironment provide an optimal hydrogel scaffold for cartilage tissue engineering application.


Assuntos
Cartilagem Articular/citologia , Cartilagem Articular/crescimento & desenvolvimento , Matriz Extracelular/química , Hidrogéis/síntese química , Oligopeptídeos/química , Tecidos Suporte , Animais , Materiais Biocompatíveis/síntese química , Bovinos , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Matriz Extracelular/efeitos da radiação , Luz , Teste de Materiais , Oligopeptídeos/efeitos da radiação , Fotoquímica/métodos , Engenharia Tecidual/instrumentação
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