Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.041
Filtrar
1.
J Photochem Photobiol B ; 197: 111539, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31301638

RESUMO

Treatment of burn injury is clinically challenging one, therefore several steps and noteworthy approaches have been taken to improve wound mechanisms. Citrus pectin plays a stabilizing agent to synthesis of ZnO nanoparticles (ZnO NPs). The present study is focused on ZnO loaded collagen/chitosan nanofibrous were synthesized by electrospinning method using ZnO NPs. The chemical structure, phase purity and morphological observation were investigated under spectroscopic and mircoscopic techniques and demonstrated their suitable properties as a wound healing material. In addition, that prepared nanoparticles loaded biopolymeric fibrous nanomaterial showed suitable antibacterial activity against S. aureus and E. coli bacterial pathogens and also in vitro studies was confirmed the enhanced proliferation, cell viability and biocompatibility. In vitro evaluations have been exhibited acceptable cell proliferation is observed throughout the ZnO loaded Coll/CS nanofibrous within 3 days, which was comparable to the control material. In vivo wound healing ability was monitored on the rat wound experimental model. From the in vivo observations, revealed that the loaded of ZnO NPs with Coll/CS nanofibrous can effectively quicken wound healing mechanism, expressed in the initial stage healing process. These results suggest that ZnO loaded collagen/chitosan nanofibrous is a potential candidate for wound healing applications with enhanced biological properties.


Assuntos
Queimaduras/patologia , Quitosana/química , Colágeno/química , Nanopartículas Metálicas/química , Nanofibras/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Queimaduras/veterinária , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Nanofibras/uso terapêutico , Nanofibras/toxicidade , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química
2.
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
3.
Gene ; 712: 143961, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31279709

RESUMO

Since international federation of gynecology and obstetrics (FIGO) staging is mainly based on clinical assessment, an integrated approach for mining RNA based biomarkers for understanding the molecular deregulation of signaling pathways and RNAs in cervical cancer was proposed in this study. Publicly available data were mined for identifying significant RNAs after patient staging. Significant miRNA families were identified from mRNA-miRNA and lncRNA-miRNA interaction network analyses followed by stage specific mRNA-miRNA-lncRNA association network generation. Integrated bioinformatic analyses of selected mRNAs and lncRNAs were performed. Results suggest that HBA1, HBA2, HBB, SLC2A1, CXCL10 (stage I), PKIA (stage III) and S100A7 (stage IV) were important. miRNA family enrichment of interacting miRNA partners of selected RNAs indicated the enrichment of let-7 family. Assembly of collagen fibrils and other multimeric structures_Homosapiens_R-HSA-2022090 in pathway analysis and progesterone_CTD_00006624 in DSigDB analysis were the most significant and SLC2A1, hsa-miR-188-3p, hsa-miR-378a-3p and hsa-miR-150-5p were selected as survival markers.


Assuntos
Biomarcadores Tumorais/metabolismo , Biologia Computacional/métodos , Mineração de Dados/métodos , RNA Neoplásico/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Colágeno/química , Metilação de DNA , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Papillomaviridae/metabolismo , Infecções por Papillomavirus/complicações , Neoplasias do Colo do Útero/virologia
4.
Soft Matter ; 15(30): 6237-6246, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334527

RESUMO

Mechanical testing of connective tissues such as tendons and ligaments can lead to collagen denaturation even in the absence of macroscale damage. The following tensile loading protocols, ramp loading to failure, overloading and release, cyclic overloading and cyclic fatigue loading, all yield molecular damage in rat or bovine tendons. Single collagen fibrils extracted from the positional common digital extensor tendon of the forelimb also show molecular damage after tensile loading to failure. Using fibrils from the same source we assess changes to the molecular and supramolecular structure after tensile stress relaxation at strains between 4 and 22% followed by release. We observe no broken fibril and no significant change in D-band spacing. However, we observe significant binding of a fluorescent collagen hybridizing peptide to the fibrils indicating that collagen denaturation occurs in a strain dependent way for relaxation times between 1 s and 1500 s. We also show that peptide binding is associated with a decrease of the cross-sectional area of the fibrils providing an estimate of the dry volume loss due to molecular denaturation as well as an estimate of the mechanical energy density required, 25-110 MJ m-3. In summary we show that collagen molecular damage can occur in the absence of fibril failure and without visible changes to the supramolecular structure.


Assuntos
Colágeno/química , Estresse Mecânico , Tendões/metabolismo , Animais , Fenômenos Biomecânicos , Bovinos , Membro Anterior/metabolismo , Ratos , Tendões/química
5.
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
6.
J Food Sci ; 84(7): 1799-1805, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218694

RESUMO

Defatting of seabass skins using pulsed electric field (PEF)-assisted process at different electric field strengths (16 and 24 kV/cm) and times (36, 72, and 108 ms) in combination with porcine pancreas lipase (PPL) at 25 U/g dry matter was investigated. PEF-treated skin at 24 kV/cm for 72 ms followed by PPL treatment removed 86.93% lipids. PEF-treated skin was further optimized for lipid reduction by response surface methodology. Central composite design was adopted to establish treatments based on two independent variables, involving PPL concentration (30 to 55 U/g dry matter) and hydrolysis time (60 to 180 min). Second-order polynomial model was used for predicting the response. The highest lipid removal (91.96 ± 1.70%) was attained when the optimal condition (42.36 PPL units/g dry skin matter for 139.78 min) was used. The experiment value was in accordance with the predicted value. PEF-PPL-treated skin had lower monounsaturated and polyunsaturated fatty acids than the solvent-extracted skin (P < 0.05). When PEF-PPL-treated skin was hydrolyzed using papain at 0.30 U/g dry matter, lower fishy odor/flavor of resulting hydrolyzed collagen (PEF-PPL-HC) was found than other samples (P < 0.05). Lower total volatile compounds were also obtained in PEF-PPL-HC sample. Thus, the use of PEF pretreatment along with PPL before papain hydrolysis effectively prevented the formation of fishy odor/flavor in hydrolyzed collagen from seabass skin. PRACTICAL APPLICATION: Fishy odor/flavor caused by lipid oxidation of fish skin hydrolysates limits their applications in foods. Defatting process is the significant step for skin pretreatment. Although several methods could remove lipids from fish skins, either by lipase or solvent extraction, fishy odor/flavor is still detected in hydrolysate. Pulsed electric field-assisted process in combination with porcine lipase is another approach that can be used to enhance efficiency via electroporation, causing the loosened skin matrix and facilitating the migration of lipase into the skin. Consequently, the resulting hydrolysate might have the lowered fishy odor/flavor and could be used in foods, especially for fortification.


Assuntos
Manipulação de Alimentos/métodos , Lipase/química , Lipídeos/química , Pele/química , Animais , Bass , Biocatálise , Colágeno/química , Ácidos Graxos Insaturados/química , Proteínas de Peixes/química , Manipulação de Alimentos/instrumentação , Humanos , Odorantes/análise , Oxirredução , Suínos , Paladar
7.
Mar Drugs ; 17(6)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151236

RESUMO

Although collagens from vertebrates are mainly used in regenerative medicine, the most elusive issue in the collagen-based biomedical scaffolds is its insufficient mechanical strength. To solve this problem, electrospun collagen composites with chitins were prepared and molecular interactions which are the cause of the mechanical improvement in the composites were investigated by two-dimensional correlation spectroscopy (2DCOS). The electrospun collagen is composed of two kinds of polymorphs, α- and ß-chitin, showing different mechanical enhancement and molecular interactions due to different inherent configurations in the crystal structure, resulting in solvent and polymer susceptibility. The collagen/α-chitin has two distinctive phases in the composite, but ß-chitin composite has a relatively homogeneous phase. The ß-chitin composite showed better tensile strength with ~41% and ~14% higher strength compared to collagen and α-chitin composites, respectively, due to a favorable secondary interaction, i.e., inter- rather than intra-molecular hydrogen bonds. The revealed molecular interaction indicates that ß-chitin prefers to form inter-molecular hydrogen bonds with collagen by rearranging their uncrumpled crystalline regions, unlike α-chitin.


Assuntos
Quitina/metabolismo , Colágeno/metabolismo , Animais , Quitina/química , Quitina/ultraestrutura , Colágeno/química , Colágeno/ultraestrutura , Cristalização , Técnicas Eletroquímicas , Humanos , Ligações de Hidrogênio , Microscopia Eletrônica de Varredura , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração
8.
Mar Drugs ; 17(5)2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31052462

RESUMO

Collagen was extracted from bigeye tuna (Thunnus obesus) skins by salting-out (PSC-SO) and isoelectric precipitation (PSC-IP) methods. The yield of the PSC-IP product was approximately 17.17% (dry weight), which was greater than the yield obtained from PSC-SO (14.14% dry weight). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that collagen from bigeye tuna skin belongs to collagen type I. Inductively coupled plasma mass spectrometry results indicate that the heavy metal abundance in PSC-IP was lower than the maximum acceptable amounts according to Chinese regulatory standards. In addition, results from a methylthiazolyldiphenyl-tetrazolium bromide assay and an in vitro scratch assay demonstrated that PSC-IP could promote the proliferation and migration of NIH-3T3 fibroblasts. Overall, results suggest PSC-IP could be used to rapidly extract collagen from marine by-products instead of traditional salting-out methods. Collagen from bigeye tuna skin may also have strong potential for cosmetic and biomedical applications.


Assuntos
Colágeno/análise , Colágeno/isolamento & purificação , Proteínas de Peixes/análise , Proteínas de Peixes/isolamento & purificação , Animais , Ensaios de Migração Celular , Proliferação de Células , Colágeno/química , Colágeno Tipo I , Proteínas de Peixes/química , Camundongos , Células NIH 3T3/efeitos dos fármacos , Pele/química , Pele/metabolismo , Solubilidade , Atum
9.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067635

RESUMO

Several biomaterials have recently been developed to address the challenge of osteochondral regeneration. Among these, chitosan holds promises both for cartilage and bone healing. The aim of this in vivo study was to evaluate the regeneration potential of a novel hybrid magnesium-doped hydroxyapatite (MgHA), collagen, chitosan-based scaffold, which was tested in a sheep model to ascertain its osteochondral regenerative potential, and in a rabbit model to further evaluate its ability to regenerate bone tissue. Macroscopic, microtomography, histology, histomorphometry, and immunohistochemical analysis were performed. In the sheep model, all analyses did not show significant differences compared to untreated defects (p > 0.05), with no evidence of cartilage and subchondral bone regeneration. In the rabbit model, this bone scaffold provided less ability to enhance tissue healing compared with a commercial bone scaffold. Moreover, persistence of scaffold material and absence of integration with connective tissue around the scaffolds were observed. These results raised some concerns about the osteochondral use of this chitosan composite scaffold, especially for the bone layer. Further studies are needed to explore the best formulation of chitosan-reinforced composites for osteochondral treatment.


Assuntos
Regeneração Óssea , Quitosana/análogos & derivados , Tecidos Suporte/efeitos adversos , Animais , Cartilagem/efeitos dos fármacos , Colágeno/química , Durapatita/química , Masculino , Coelhos , Ovinos , Tecidos Suporte/química
10.
Int J Nanomedicine ; 14: 2683-2692, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31043781

RESUMO

Purpose: We aimed to fabricate guided bone regeneration (GBR) membrane using polyglycerol sebacate (PGS) and investigate the impact of scaffold pore size on osteogenesis. Materials and methods: PGS microporous membrane was fabricated by salt-leaching technique with various pore sizes. Twenty-eight male New Zealand rabbits were randomly divided into four groups: 25 µm PGS membrane, 53 µm PGS membrane, collagen membrane, and blank control group. Subsequently, standardized and critical-sized tibia defects were made in rabbits and the defective regions were covered with the specifically prepared membranes. After 4 and 12 weeks of in vivo incubation, bone samples were harvested from tibia. Micro-computed tomography scanning was performed on all bone samples. A three-dimensional visible representation of the constructs was obtained and used to compare the ratios of the ossifying volume to total construct volume (bone volume to tissue volume [BV/TV]) of each sample in different groups; then, bone samples were stained with H&E and Masson's trichrome stain for general histology. Results: At 4 weeks, the BV/TV in the 25 µm PGS group was found higher than that in the 53 µm PGS and collagen groups. At 12 weeks, the bone defect site guided by the 25 µm PGS membrane was almost completely covered by the new bone. However, the site guided by the 53 µm PGS membrane or collagen membrane was covered only most of the defects and the left part of the defect was unoccupied. Histological observation further verified these findings. Conclusion: We thus concluded that the 25 µm PGS membrane played an advantageous role during 4-12 weeks as compared with those earlier degraded counterparts.


Assuntos
Regeneração Óssea/fisiologia , Elastômeros/química , Glicerol/química , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Polímeros/química , Animais , Colágeno/química , Masculino , Osteogênese , Porosidade , Coelhos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Microtomografia por Raio-X
12.
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
13.
Mar Drugs ; 17(4)2019 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-31013895

RESUMO

A previous report indicated that collagen hydrolysate fraction (F7) from Spanish mackerel (Scomberomorous niphonius) skins showed high reducing power and radical scavenging activities on 2,2-Diphenyl-1-picrylhydrazyl (DPPH) (EC50 value of 1.57 mg/mL) and hydroxyl (EC50 value of 1.20 mg/mL). In this work, eight peptides were isolated from F7 and identified as Gly-Pro-Tyr (GPY, 335.31 Da), Gly-Pro-Thr-Gly-Glu (GPTGE, 459.47 Da), Pro-Phe-Gly-Pro-Asp (PFGPD, 531.52 Da), Gly-Pro-Thr-Gly-Ala-Lys (GPTGAKG, 586.65 Da), Pro-Tyr-Gly-Ala-Lys-Gly (PYGAKG, 591.69 Da), Gly-Ala-Thr-Gly-Pro-Gln-Gly (GATGPQG, 586.61 Da), Gly-Pro-Phe-Gly-Pro-Met (GPFGPM, 604.73 Da), and Tyr-Gly-Pro-Met (YGPM, 466.50 Da), respectively. Among them, PFGPD, PYGAKG, and YGPM exhibited strong radical scavenging activities on DPPH (EC50 values of 0.80, 3.02, and 0.72 mg/mL for PFGPD, PYGAKG, and YGPM, respectively), hydroxyl (EC50 values of 0.81, 0.66, and 0.88 mg/mL for PFGPD, PYGAKG, and YGPM, respectively), superoxide anion (EC50 values of 0.91, 0.80, and 0.73 mg/mL for PFGPD, PYGAKG, and YGPM, respectively), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) cation (EC50 values of 0.86, 1.07, and 0.82 mg/mL for PFGPD, PYGAKG, and YGPM, respectively) in a positive concentration-activity relationship. Furthermore, PFGPD, PYGAKG, and YGPM could effectively reduce Fe3+ to Fe2+ and inhibit lipid peroxidation. Hence, eight collagen peptides from hydrolysate of Spanish mackerel skins might be served as antioxidant candidates for various industrial applications.


Assuntos
Antioxidantes/química , Colágeno/química , Colágeno/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Perciformes/metabolismo , Pele/química , Animais , Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Hidrolisados de Proteína/metabolismo , Superóxidos/metabolismo
14.
Int J Mol Sci ; 20(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018582

RESUMO

BACKGROUND: Osteocytes are the key regulator cells in bone tissue, affecting activity of both osteoblasts and osteoclasts. Current in vitro studies on osteocyte-osteoblast interaction are invariably performed with rodent cells, mostly murine cell lines, which diminishes the clinical relevance of the data. OBJECTIVE: The objective of the present study was to establish an in vitro co-culture system of osteoblasts and osteocytes, which is based solely on human primary cells. METHODS: Three different approaches for the generation of human primary osteocytes were compared: direct isolation of osteocytes from bone tissue by multistep digestion, long-time differentiation of human pre-osteoblasts embedded in collagen gels, and short time differentiation of mature human osteoblasts in collagen gels. Co-cultivation of mature osteoblasts with osteocytes, derived from the three different approaches was performed in a transwell system, with osteocytes, embedded in collagen gels at the apical side and osteoblasts on the basal side of a porous membrane, which allowed the separate gene expression analysis for osteocytes and osteoblasts. Fluorescence microscopic imaging and gene expression analysis were performed separately for osteocytes and osteoblasts. RESULTS: All examined approaches provided cells with typical osteocytic morphology, which expressed osteocyte markers E11, osteocalcin, phosphate regulating endopeptidase homolog, X-linked (PHEX), matrix extracellular phosphoglycoprotein (MEPE), sclerostin, and receptor activator of NF-κB Ligand (RANKL). Expression of osteocyte markers was not significantly changed in the presence of osteoblasts. In contrast, osteocalcin gene expression of osteoblasts was significantly upregulated in all examined co-cultures with differentiated osteocytes. Alkaline phosphatase (ALPL), bone sialoprotein II (BSPII), and RANKL expression of osteoblasts was not significantly changed in the co-culture. CONCLUSION: Interaction of osteoblasts and osteocytes can be monitored in an in vitro model, comprising solely primary human cells.


Assuntos
Técnicas de Cocultura/métodos , Colágeno/química , Géis/química , Osteoblastos/citologia , Osteócitos/citologia , Tecidos Suporte/química , Idoso , Materiais Biocompatíveis/química , Diferenciação Celular , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Mater Sci Eng C Mater Biol Appl ; 101: 487-498, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029343

RESUMO

Wound dressing is distinctly important to wound healing, because it can not only protect wound from external disturbance, but also provide an ideal environment for wound closure. However, most of wound dressings need additional active ingredients to assist the repair process. In order to develop new dressings that can present spontaneous healing activity, herein, an injectable hydrogel consisted of collagen I and hyaluronic acid has been designed to mimic extracellular matrix for vascular cells growing and wound closure. The preparation of hydrogel (COL-HA) was realized through in situ coupling of phenol moieties of collagen I-hydroxybenzoic acid (COL-P) and hyaluronic-acid-tyramine (HA-Tyr) through horseradish peroxidase (HRP). The physical structure and properties were characterized, and the biological performances were analyzed. COL-HA hydrogel presented porous structure that contributed to the exchange of gas, medium and nutrition. Human microvascular endothelial cells (HMEC) and fibroblasts (COS-7) cultured within this hydrogel showed significant proliferation behaviors. More importantly, a certain level of vascular endothelial growth factor (VEGF) was observed in HMEC cultured hydrogel, which led to the possibility of vascular regeneration. For the full-thickness wound, the healing ratio and validity of wound treated with COL-HA hydrogel were higher than commercial drug and individual COL-P hydrogel, HA-Tyr hydrogel groups, since collagen and hyaluronic acid made joint efforts to improve wound repair.


Assuntos
Biomimética/métodos , Colágeno/química , Colágeno/farmacologia , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Hidrogéis/química , Cicatrização/efeitos dos fármacos , Animais , Células COS , Linhagem Celular , Cercopithecus aethiops , Humanos
16.
Mater Sci Eng C Mater Biol Appl ; 101: 640-649, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029358

RESUMO

In this study, type I collagen membranes were prepared using oligomeric proanthocyanidins (OPCs) as the cross-linking agent. The fabricated materials were evaluated to be applied as guided tissue regeneration membranes for periodontal defects. The mechanical strength of the cross-linked collagen membranes, namely OPCs-Col films, using different concentrations of OPCs ranged from 30 to 60 kPa. The cross-linked collagen membranes had better thermal stability than non-cross-linked one and could effectively resist the decomposition in collagenase solution as long as fifty days. The results of material characterization showed that 10% OPCs-Col film was ideal for our purpose. In vitro study using L929 and MG-63 cells revealed that 10% OPCs-Col film had great biocompatibility while OPC was demonstrated to be not cytotoxic as glutaraldehyde and genipin but even promote L929 cells. The material was further studied for in vivo studies with two models, subcutaneous and cranium defects in rat. The subcutaneous test showed that the regeneration membrane degraded till one month and the inflammatory response also reduced with implantation time. When implanted into the cranium defect, no lesions of the brain were caused and new bone tissue was observed inside the material. The results of in vivo studies showed that the synthesized membrane was helpful for tissue regeneration with long degradation time. The tissue regeneration membranes can barrier the rapid growing soft tissue, in order to save the capacity for the growth of neo bone.


Assuntos
Materiais Biocompatíveis/química , Colágeno/química , Regeneração Tecidual Guiada Periodontal/métodos , Proantocianidinas/química , Animais , Materiais Biocompatíveis/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Proantocianidinas/efeitos adversos , Ratos
17.
Int J Mol Sci ; 20(7)2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970594

RESUMO

The cell microenvironment plays a pivotal role in mediating cell adhesion, survival, and proliferation in physiological and pathological states. The relevance of extracellular matrix (ECM) proteins in cell fate control is an important issue to take into consideration for both tissue engineering and cell biology studies. The glycosylation of ECM proteins remains, however, largely unexplored. In order to investigate the physio-pathological effects of differential ECM glycosylation, the design of affordable chemoselective methods for ECM components glycosylation is desirable. We will describe a new chemoselective glycosylation approach exploitable in aqueous media and on non-protected substrates, allowing rapid access to glyco-functionalized biomaterials.


Assuntos
Materiais Biocompatíveis/metabolismo , Técnicas de Cultura de Células/métodos , Proteínas da Matriz Extracelular/metabolismo , Materiais Biocompatíveis/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Colágeno/química , Colágeno/farmacologia , Glicosilação , Humanos
18.
Mater Sci Eng C Mater Biol Appl ; 101: 370-379, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029330

RESUMO

Vascularization is of great importance in the successful translation of tissue engineered constructs into clinically relevant application. The lack of a general approach to rapidly construct vascular networks in engineered constructs remains a major challenge. Herein, an adhesive hydrogel-based tissue construct, in which cell-affinitive domains and interconnected channels were concurrently constructed, was put forward to enhance vascularization. Hydrogel matrix was modified with Arg-Gly-Asp (RGD) peptide to supply cell adhesion sites. Collagen fibers were added into the hydrogel matrix to produce interconnected vessel-like channels via enzyme mediated degradation. In a bone-like model, the successful outspread morphology and intensive function expression of osteo-like cells and the formation of endothelial cells-lined channels were observed, suggesting it's flexible to functionalize extracellular matrix with vessel-like channels via the introduction of endothelial cells-laden fibers. Our approach furnishes a particular strategy to build vascular architecture and is especially attractive in the bioengineering of rich vascularized tissues.


Assuntos
Hidrogéis/química , Neovascularização Fisiológica , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Bovinos , Forma Celular , Colágeno/química , Colagenases/metabolismo , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neovascularização Fisiológica/genética , Osteogênese/genética
19.
J Agric Food Chem ; 67(16): 4671-4678, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30929424

RESUMO

Collagen-derived hydroxyproline (Hyp)-containing oligopeptides, known to have various physiological functions, are detected in blood at markedly higher concentrations after oral ingestion of collagen hydrolysate. Monitoring the absorption and metabolism of the bioactive peptides is essential to investigate the beneficial effects of collagen hydrolysate. We previously developed an internal standard mixture by sequential protease digestion of stable isotope-labeled collagen, which enabled highly accurate quantitation of collagen-derived oligopeptides by liquid chromatography-mass spectrometry (LC-MS). However, the use of proteases caused a profound imbalance in the generated peptides. Here, we employed partial acid hydrolysis to achieve more efficient and balanced peptide generation. Various stable isotope-labeled oligopeptides were detected after 0.5 h acid hydrolysis, and marked enhancement of peptide generation compared with the previous enzymatic method was observed, especially for Hyp-Gly (27.8 ± 0.6 ng/µg vs 0.231 ± 0.02 ng/µg). The acid hydrolysate was then heated to generate labeled cyclic dipeptides. Using the novel internal standard mixture in LC-MS, we were able to simultaneously quantitate 23 collagen-derived oligopeptides in human plasma and urine after oral administration of collagen hydrolysate.


Assuntos
Colágeno/química , Colágeno/metabolismo , Ácidos/química , Adulto , Animais , Isótopos de Carbono/análise , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Marcação por Isótopo , Masculino , Isótopos de Nitrogênio/análise , Peptídeos/química , Peptídeos/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Pele/química , Suínos , Espectrometria de Massas em Tandem , Adulto Jovem
20.
Int J Nanomedicine ; 14: 2127-2144, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988613

RESUMO

Purpose: A promising vascular scaffold must possess satisfying mechanical properties, great hemocompatibility, and favorable tissue regeneration. Combining natural with synthetic materials is a popular method of creating/enhancing such scaffolds. However, the effect of additional modification on the materials requires further exploration. Materials and methods: We selected polycaprolactone (PCL), which has excellent mechanical properties and biocompatibility and can be combined with collagen. Electrospun fibers created using a PCL/collagen solution were used to fashion mixed nanofibers, while separate syringes of PCL and collagen were used to create separated nanofibers, resulting in different pore sizes. Mixed and separated nanofibers were cross-linked with glutaraldehyde (GA), 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), and genipin; hence, we named them as mixed GA, mixed EDC (ME), mixed genipin (MG), separated GA, separated EDC (SE), and separated genipin (SG). Results: Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction showed that cross-linking did not affect the main functional groups of fibers in all groups. ME, MG, SE, and SG met the requisite mechanical properties, and they also resisted collagenase degradation. In hemocompatibility assays, only ME and MG demonstrated ideal safety. Furthermore, ME and MG presented the greatest cytocompatibility. For vascular scaffolds, rapid endothelialization helps to prevent thrombosis. According to human umbilical vein endothelial cell migration on different nanofibers, ME and MG are also successful in promoting cell migration. Conclusion: ME and MG may be promising candidates for vascular tissue engineering. The study suggests that collagen cross-linked by EDC/N-hydroxysuccinimide or genipin facilitates endothelial cell regeneration, which could be of great benefit in tissue engineering of vascular scaffolds.


Assuntos
Colágeno/química , Células Endoteliais/citologia , Iridoides/química , Nanofibras/administração & dosagem , Poliésteres/química , Succinimidas/química , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Carbodi-Imidas/química , Movimento Celular , Células Cultivadas , Reagentes para Ligações Cruzadas/química , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Teste de Materiais , Nanofibras/química , Adesividade Plaquetária , Coelhos , Ratos , Regeneração , Engenharia Tecidual/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA