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1.
Braz. j. oral sci ; 20: e211512, jan.-dez. 2021. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1254424

RESUMO

Aim: Several systemic diseases, such as periodontitis and apical periodontitis, can cause extensive bone resorption. Host defense peptides may have the potential for the development of novel therapies for the bone resorption process. This study evaluated the potential of host defense peptides clavanins A, MO, and LL-37 in in vitro osteoclastogenesis. Methods: RAW 264.7 cultures were stimulated with recombinant of receptor activator of nuclear factor kappa B ligand in the presence of different tested concentrations of host defense peptides, besides calcium hydroxide and doxycycline. Cellular viability, nitric oxide production, and a number of differentiated osteoclast-like cells were also evaluated. Results: Results showed that none of the substances were cytotoxic, except for 128 µg.mL-1 of doxycycline after 3 days. Host defense peptides, calcium hydroxide, and doxycycline did not interfere in nitric oxide production or downregulated it. An exception was observed in the presence of 2 µg.mL-1 of doxycycline, in which nitric oxide production was up-regulated. All host defense peptides were capable of reducing osteoclast-like cell differentiation. Conclusion: Host defense peptides clavanins A and MO demonstrated to be potential suppressors of osteoclastogenesis in vitro without interfering in cellular viability and nitric oxide production. These promising results need to be further analyzed in in vivo models of bone resorption


Assuntos
Osteogênese , Reabsorção Óssea , Peptídeos Catiônicos Antimicrobianos , Óxido Nítrico
2.
J Craniofac Surg ; 32(6): 2245-2250, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516061

RESUMO

PURPOSE: Extracellular vesicles (EVs) are responsible for intercellular communication. Mesenchymal stem cell-derived vesicles have been shown to have similar properties as functional mesenchymal stem cells. The aim of this study was to compare the therapeutic benefit of EVs obtained from adipose tissue-derived stem cells (ADSC) on bone repair whereas using ß-tricalcium phosphate (ß-TCP) biomaterial as a carrier. MATERIALS AND METHOD: A single critical size bone defect of 8 mm in diameter was created on the right side of rat calvarium using a custom-made punch needle. Animals were randomly divided into 5 groups: group 1 (no treatment), group 2 (bone graft), group 3 (ß-TCP + ADSC), group 4 (ß-TCP + EV), group 5 (ß-TCP). Eight weeks later, animals were sacrificed and histologic and radiologic evaluation was performed. RESULTS: Semiquantitative histologic scoring demonstrated significantly higher bone regeneration scores for groups 2, 3, and 4 compared to group 1. Radiologic imaging showed significantly higher bone mineral density for groups 2, 3, and 5 compared to group 1. There were no significant differences between treatment groups in either histologic or radiologic scoring. CONCLUSIONS: Our data showed that EVs provided from thermally induced ADSCs did not show any significant difference in bone regeneration when compared to ADSCs themselves. Future studies should focus on determining the optimum amount and content of EV application since these vary significantly depending on the microenvironment.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Tecido Adiposo , Animais , Regeneração Óssea , Osteogênese , Ratos , Células-Tronco
3.
Nanoscale ; 13(34): 14382-14398, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473168

RESUMO

Graphene derivatives combined with polymers have attracted enormous attention for bone tissue engineering applications. Among others, reduced graphene oxide (rGO) is one of the preferred graphene-based fillers for the preparation of composites via melt compounding, and their further processing into 3D scaffolds, due to its established large-scale production method, thermal stability, and electrical conductivity. In this study, rGO (low bulk density 10 g L-1) was compacted by densification using a solvent (either acetone or water) prior to melt compounding, to simplify its handling and dosing into a twin-screw extrusion system. The effects of rGO bulk density (medium and high), densification solvent, and rGO concentration (3, 10 and 15% in weight) on rGO dispersion within the composite, electrical conductivity, printability and cell-material interactions were studied. High bulk density rGO (90 g L-1) occupied a low volume fraction within polymer composites, offering poor electrical properties but a reproducible printability up to 15 wt% rGO. On the other hand, the volume fraction within the composites of medium bulk density rGO (50 g L-1) was higher for a given concentration, enhancing rGO particle interactions and leading to enhanced electrical conductivity, but compromising the printability window. For a given bulk density (50 g L-1), rGO densified in water was more compacted and offered poorer dispersability within the polymer than rGO densified in acetone, and resulted in scaffolds with poor layer bonding or even lack of printability at high rGO percentages. A balance in printability and electrical properties was obtained for composites with medium bulk density achieved with rGO densified in acetone. Here, increasing rGO concentration led to more hydrophilic composites with a noticeable increase in protein adsorption. Moreover, scaffolds prepared with such composites presented antimicrobial properties even at low rGO contents (3 wt%). In addition, the viability and proliferation of human mesenchymal stromal cells (hMSCs) were maintained on scaffolds with up to 15% rGO and with enhanced osteogenic differentiation on 3% rGO scaffolds.


Assuntos
Grafite , Comunicação Celular , Humanos , Osteogênese , Polímeros , Tecidos Suporte
4.
Mater Sci Eng C Mater Biol Appl ; 128: 112288, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474839

RESUMO

The bone extracellular matrix (ECM) is a composite scaffold having inorganic hydroxyapatite and organic collagen fibers. Synthetic bone repair scaffolds that mimic the chemical composition of the native ECM and capable of delivering therapeutics are beneficial. In this study, we prepared intrinsically fluorescent organic-inorganic hybrid microparticle biomaterials by sol-gel process. Unlike the conventional Stöber process which requires an alkaline condition for microparticle formation, an acidic condition in the presence of a biodegradable poly(ester amide) (PEA) polymer was used to prepare silica and tertiary bioactive glass hybrids. During their preparation, one or two model drugs were loaded in the microparticles. Our results showed that a gelation temperature between 40 °C-60 °C and the inclusion of PEA were critical for microparticle formation. Unexpectedly, the hybrid microparticles were fluorescent with tunable emission by changing the excitation wavelengths ranging from 300 to 565 nm for potential multiplex imaging. Gene expression studies showed that the hybrid materials induce osteogenic differentiation of 10T1/2 cells without adding exogenous biochemical factors. The bioactivity of the inorganic phase and the dual drug release from homogenous, biodegradable, biocompatible, osteoinductive, and intrinsically fluorescent microparticles may offer a unique platform for bone regeneration and therapy.


Assuntos
Preparações Farmacêuticas , Tecidos Suporte , Amidas , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Ésteres , Osteogênese
5.
Mater Sci Eng C Mater Biol Appl ; 128: 112295, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474846

RESUMO

It is of great significance to develop osteoinductive artificial scaffold for bone repair and regeneration. We constructed a biomimetic apatite interface on electrospun polycaprolactone fibers by combining layer-by-layer (LbL) nanocoating with mineralization to fabricate an osteoinductive artificial scaffold. After polydopamine modification, cationic type-І collagen and anionic chondroitin sulfate were sequentially adsorbed on the fiber surface. The fibers coated with the multilayer components served as the precursor matrix to induce apatite deposition. By adjusting the number of the layers and duration of mineralization, the nanoscale morphology of composite fibers was optimized. When ten bilayers of the collagen and chondroitin sulfate were deposited onto the fibers followed by one day-mineralization, the obtained polycaprolactone-apatite composite scaffolds significantly promoted the adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells. In a subcutaneous implantation in mice, this composite fiber membrane enhanced in vivo ectopic osteogenesis. Our nano-architectural scaffolds were able to mimic the composition and structure of the bone matrix to a certain extent, holding great potential for bone repair and regeneration.


Assuntos
Sulfatos de Condroitina , Osteogênese , Animais , Regeneração Óssea , Diferenciação Celular , Colágeno , Camundongos , Tecidos Suporte
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112299, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474850

RESUMO

A novel airflow shearing method was introduced to prepare microspheres efficiently with precisely control of microsphere size and homogeneity. The effects of technical parameters in the formation of the microspheres, such as solution concentration, nozzle size and airflow strength, were investigated. By optimizing the technical parameters (8% PLGA concentration, 27-32 G nozzle size, 6-8 l/min airflow strength), nano-hydroxyapatite and poly(lactide-co-glycolide) nanocomposite (nHA/PLGA) microspheres with a diameter around 250 µm and up to 40 wt% nHA content was prepared successfully. Especially, the microspheres possessed revealed great homogeneity and unique "acorn" appearance with two sides: A hard smooth side as well as a crumpled rough side, generated in the preparation process. Furthermore, the nHA/PLGA microspheres' potential application in bone tissue engineering was studied. In vitro, enhanced proliferation and osteogenic differentiation of the MC3T3-E1 cells was observed on as-prepared nHA/PLGA microspheres with high nHA content. In vivo, the BV/TV value of the microspheres with 20 wt% nHA was up to 75% and similar to the clinical products' performance. Moreover, beside high nHA content, the rough porous surface leads to bone ingrowth, which plays an important role in accelerating bone repair. Therefore, airflow shearing method could be an effective approach to fabricate biocompatible microsphere, and the as-prepared microspheres showed unique surface state and bone repair ability and making them as potential candidates for bone tissue engineering and bone implantation clinical applications.


Assuntos
Durapatita , Nanocompostos , Células Cultivadas , Dioxanos , Ácido Láctico , Microesferas , Osteogênese , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
7.
Mater Sci Eng C Mater Biol Appl ; 128: 112306, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474857

RESUMO

Osteomyelitis is caused by Staphylococcus aureus (S. aureus), with associated progressive bone loss. This study developed for the first time a calcium phosphate cement (CPC) for delivery of doxycycline (DOX) and human platelet lysate (hPL) to fight against S. aureus infection and enhance the osteogenesis of human periodontal ligament stem cells (hPDLSCs). Chitosan-containing CPC scaffolds were fabricated in the absence (CPCC) or presence of DOX (CPCC+DOX). In addition, hPL was encapsulated in alginate microbeads and incorporated into CPCC+DOX (CPCC+DOX+ hPL). Flexural strength of CPCC+DOX + hPL was (5.56 ± 0.55) MPa, lower than (8.26 ± 1.6) MPa of CPCC+DOX (p < 0.05), but exceeding the reported strength of cancellous bone. CPCC+DOX and CPCC+DOX + hPL exhibited strong antibacterial activity against S. aureus, reducing biofilm CFU by 4 orders of magnitude. The hPDLSCs encapsulated in microbeads were co-cultured with the CPCs. The hPDLSCs were able to be released from the microbeads and showed a high proliferation rate, increasing by about 8 folds at 14 days for all groups. The hPL was released from the scaffold and promoted the osteogenic differentiation of hPDLSCs. ALP activity was 28.07 ± 5.15 mU/mg for CPCC+DOX + hPL, higher than 17.36 ± 2.37 mU/mg and 1.34 ± 0.37 mU/mg of CPCC+DOX and CPCC, respectively (p < 0.05). At 7 days, osteogenic genes (ALP, RUNX2, COL-1, and OPN) in CPCC+DOX + hPL were 3-10 folds those of control. The amount of hPDLSC-synthesized bone mineral with CPCC+DOX + hPL was 3.8 folds that of CPCC (p < 0.05). In summary, the novel CPC + DOX + hPL-hPDLSCs scaffold exhibited strong antibacterial activity, excellent cytocompatibility and hPDLSC osteogenic differentiation, showing a promising approach for treatment and prevention of bone infection and enhancement of bone regeneration.


Assuntos
Osteogênese , Ligamento Periodontal , Biofilmes , Fosfatos de Cálcio/farmacologia , Diferenciação Celular , Células Cultivadas , Humanos , Staphylococcus aureus , Células-Tronco
8.
Mater Sci Eng C Mater Biol Appl ; 128: 112309, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474860

RESUMO

Recently, black phosphorus (BP) has garnered great attention as one of newly emerging two-dimensional nanomaterials. Especially, the degraded platelets of BP in the physiological environment were shown to be nontoxic phosphate anions, which are a component of bone tissue and can be used for mineralization. Here, our study presents the potential of BP as biofunctional and biocompatible nanomaterials for the application to bone tissue engineering and regeneration. An ultrathin layer of BP nanodots (BPNDs) was created on a glass substrate by using a flow-enabled self-assembly process, which yielded a highly uniform deposition of BPNDs in a unique confined geometry. The BPND-coated substrates represented unprecedented favorable topographical microenvironments and supportive matrices suitable for the growth and survival of MC3T3-E1 preosteoblasts. The prepared substrates promoted the spontaneous osteodifferentiation of preosteoblasts, which had been confirmed by determining alkaline phosphatase activity and extracellular calcium deposition as early- and late-stage markers of osteogenic differentiation, respectively. Furthermore, the BPND-coated substrates upregulated the expression of some specific genes (i.e., RUNX2, OCN, OPN, and Vinculin) and proteins, which are closely related to osteogenesis. Conclusively, our BPND-coating strategy suggests that a biologically inert surface can be readily activated as a cell-favorable nanoplatform enabled with excellent biocompatibility and osteogenic ability.


Assuntos
Osteoblastos , Osteogênese , Diferenciação Celular , Fósforo , Engenharia Tecidual
9.
Mater Sci Eng C Mater Biol Appl ; 128: 112315, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474866

RESUMO

Implant surface plays a crucial role in improving osseointegration and long-term implant life. When the implant comes in contact with the bone tissue, the bone marrow mesenchymal cells interact with the implant surface and the surface properties such as morphology, wettability, mechanical properties and chemistry influences cell migration, proliferation and differentiation. Different surface modification strategies such as ceramic coatings, surface dealloying, and surface topography modifications for improving osteointegration have been investigated. However, studies have not yet established which of the surface property is more influential. In this study, titanium surfaces were treated hydrothermally with sodium hydroxide and sulfuric acid separately. This treatment led to the development of two unique surface topography at nanoscale. These modified surfaces were characterized for surface morphology, wettability, chemistry, and crystallinity. Cytotoxicity, cell adhesion, proliferation, morphology, and differentiation of adipose derived stem cells on modified surfaces was investigated. The results indicate that wettability does influence initial cell adhesion. However, the surface morphology can play major role in cell spreading, proliferation and differentiation. The results indicate that titanium surfaces treated hydrothermally with sodium hydroxide led to a nanoporous architecture that promoted appropriate cell interaction with the surface promoting osteoblastic lineage.


Assuntos
Osteogênese , Titânio , Adesão Celular , Diferenciação Celular , Proliferação de Células , Osseointegração , Osteoblastos , Células-Tronco , Propriedades de Superfície , Titânio/farmacologia
10.
Mater Sci Eng C Mater Biol Appl ; 128: 112322, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474873

RESUMO

Many studies were conducted to change the surface morphology and chemical composition of Ti implants for the improvement of antibacterial ability and osseointegration between medical Ti and surrounding bone tissue. In this study, we successfully prepared a novel dual-function coating on pure Ti surface, i.e. Cu and Mg-co-doped TiO2 nanotube (TN) coating, by combining anodisation and hydrothermal treatment (HT), which could act as a delivery platform for the sustained release of Cu and Mg ions. Results showed that the amounts of Cu and Mg were about 5.43 wt%-6.55 wt% and 0.69 wt%-0.73 wt%, respectively. In addition, the surface morphology of Cu and Mg-co-doped TN (CuMTN) coatings transformed into nanoneedles after HT for 1 h. Compared with TN, CuMTN had no change in roughness and remarkable improved hydrophilicity. Antibacterial tests revealed that CuMTN had an antibacterial rate of more than 93% against Escherichia coli and Staphylococcus aureus, thereby showing excellent antibacterial properties. In addition, CuMTN could induce the formation of apatite well after being immersed in simulated body fluid, showing good biological activity. Preosteoblasts (MC3T3-E1) cultured on CuMTN-coated Ti demonstrated better proliferation and osteogenic differentiation than pristine and as-anodised specimens. To the best of our best knowledge, this study had successfully attempted to combine anodisation and HT, introduce Cu/Mg elements and functionalise Ti-based implant surfaces with enhanced hydrophilicity, osteogenesis and antimicrobial properties that can meet clinical needs for the first time.


Assuntos
Nanotubos , Osteogênese , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Íons/farmacologia , Propriedades de Superfície , Titânio/farmacologia
11.
Mater Sci Eng C Mater Biol Appl ; 128: 112325, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474876

RESUMO

Endogenous microscopic electric cues play an essential role in bone's remodeling and self-repair. Modulating the extracellular electrical environment, by means of external electric stimulation or changing surface potential of implants, was manifested to facilitate the osteointegration. The microscopic potential difference, originating from heterogeneous microstructures of materials, may mimic the endogenous electric signals to stimulate surrounding cells. In this study, the spark-plasma sintered Ti/Ta hybrid metal was fabricated and utilized to realize a surface microscopic potential difference at the same magnitude as endogenous potentials. Activated by the electric stimulation, the mesenchymal stem cells exhibited the anisotropic and polygonal cellular morphology on the Ti/Ta hybrid metal. The microscopic electric potential difference coordinated the cells proliferation on the subsequent days. Moreover, the results showed that the osteo-lineage differentiation on Ti/Ta hybrid metal were in vitro boosted over the control groups. Tailoring microstructures of material to obtain a reasonable electric microenvironment may be a necessary principle to achieve more favorable cell responses to implants, suggesting an extra degree of freedom in bone-repairing material design.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Diferenciação Celular , Proliferação de Células , Humanos , Titânio
12.
Mater Sci Eng C Mater Biol Appl ; 128: 112347, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474897

RESUMO

Although the use of bioactive ions and proteins are crucial for bone defect repair, delivering them in a stable and controlled manner remains challenging. To achieve controlled delivery of osteogenic active factor, we developed a novel double network (DN) hydrogel capable of co-delivering Mg2+ ions and BMP2 in a controlled localized manner. This DN hydrogel was composed of poly (acrylamide) and chitosan, in which the poly (acrylamide) was cross-linked via covalent bond and the chitosan was grafted using bisphosphonate (BP) to form metal coordination bonds with Mg2+ ions. Due to this dynamic dissociation and re-association of the "BP-Mg2+" coordination bond, it was possible to deliver Mg2+ ions in a stable and controlled manner. Additionally, the obtained DN hydrogel exhibited an effective tensile strength (0.62 MPa), perfect stretchability (973% fracture strain), and good creep and recovery properties due to the dynamic cross-linking effect of "BP-Mg2+". Additionally, the hydrogel could synergistically promote the proliferation and differentiation of mouse embryo osteoblast precursor cells (MC3T3-E1 cells) in vitro via the BMP2/Wnt pathway. In the skull defect rat model, this positive delivery government of Mg2+ ions and BMP2 synergistically accelerated bone regeneration. In conclusion, this dynamic cross-linked hydrogel containing Mg2+ ions established a new platform for the sustained release of osteogenesis factor and accelerated the bone regeneration process.


Assuntos
Hidrogéis , Magnésio , Animais , Proteína Morfogenética Óssea 2 , Regeneração Óssea , Diferenciação Celular , Íons , Camundongos , Osteogênese , Ratos
13.
Mater Sci Eng C Mater Biol Appl ; 128: 112349, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474898

RESUMO

Concise, low-cost preparation of titanium alloy implants with high cell proliferation and osteogenic differentiation is urgently needed. Nanosecond laser ablation of titanium alloy has the advantages of short processing time, less pollution, and non-contact. In this research, we adopt a nanosecond UV laser to process the closed groove and cross groove titanium alloys with length to width ratio of 1:1, 2.5:1, 4:1, and 6:1. The surface morphology, surface roughness, phase, element distribution, surface chemistry, and wettability were characterized. The effect of the patterned surface's properties on the adhesion, proliferation, and osteogenic differentiation of stem cells was studied. The results show the laser-ablated lattice structure's surface energy can increase rapidly in the natural environment. The cell adhesion of stem cells on a lattice structure with low roughness and high surface energy is optimal. The element concentration at the ablated edges is higher than at the bottom under Marangoni and surface tension. Stem cells preferentially adhere to the ablated edges with high roughness, element concentration, and hardness. Cell differentiation is chiefly affected by patterning structure. On the surface of the boss structure with a length to width ratio of 2.5:1, the proportion of cell length to diameter is about 2.5, and the cell area is greater. The osteogenic differentiation of cells is the highest on the surface.


Assuntos
Ligas , Titânio , Diferenciação Celular , Proliferação de Células , Lasers , Osteoblastos , Osteogênese , Propriedades de Superfície , Titânio/farmacologia
14.
Mater Sci Eng C Mater Biol Appl ; 128: 112353, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474901

RESUMO

Cobalt-chromium (CoCr)-based alloys have emerged as an interesting biomaterial within biomedical field, mainly considering their biocompatibility, resistance to corrosion and absence of magnetism; however, its effect on cell metabolism is barely known and this prompted us better evaluating whether CoCr-enriched medium affects the metabolism of both osteoblast and endothelial cells, and also if there is a coupling between them. This is also considered here the already-known effect of Cobalt (Co) as a hypoxic element. Firstly, discs of CoCr [subjecting (W) or not (Wo) to dual acid-etched (DAE)] were incubated into FBS-free cell culture medium up to 24 h (37 °C). This CoCr-enriched medium was further used to treat shear-stressed endothelial cells cultures up to 72 h. Thereafter, the conditioned medium containing metabolites of shear-stressed endothelial cells in response to CoCr-enriched medium was further used to subject osteoblast's cultures, when the samples were properly harvested to allow the analysis of the molecular issues. Our data shows that CoCr-enriched medium contains 1.5 ng-2.0 ng/mL of Co, which was captured by endothelial cells and osteoblasts in about 30% in amount and it seems modulate their metabolic pathways: shear-stressed endothelial cells expressed higher profile of HIF1α, VEGF and nNOS genes, while their global profile of protein carbonylation was lower than the control cultures, suggesting lower oxidative stress commitment. Additionally, osteoblasts responding to metabolites of CoCr-challenged endothelial cells show dynamic expression of marker genes in osteogenic differentiation, with alkaline phosphatase (ALP), osteocalcin, and bone sialoprotein (BSP) genes being significantly increased. Additionally, tensional shear-stress forces decrease the stimulus for ColA1gene expression in osteoblasts responding to endothelial cells metabolites, as well as modifying the extracellular matrix remodeling related genes. Analyzing the activities of matrix metalloproteinases (MMPs), the data shows that shear-stressed endothelial cells metabolites increase the activities of both MMP9 and MMP2 in osteoblasts. Altogether, our data shows for the first time that shear-stressed endothelial metabolites responding to CoCr discs contribute to osteogenic phenotype in vitro, and this predicts an active crosstalk between angiogenesis and osteogenesis during osseointegration of CoCr alloy and bone healing, maybe guided by the Co-induced hypoxic condition.


Assuntos
Cromo , Cobalto , Diferenciação Celular , Cobalto/farmacologia , Meios de Cultivo Condicionados/farmacologia , Células Endoteliais , Osteoblastos , Osteogênese
15.
Mater Sci Eng C Mater Biol Appl ; 128: 112354, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474902

RESUMO

In this paper, silk fibroin (SF) porous microcarriers containing strontium were constructed as injectable bone tissue engineering vehicles. The effects of SF concentration and strontium content on micromorphology, element distribution, strontium ion release and cellular behavior of the constructed microcarriers were investigated. The microcarriers with an open interconnected pore can be fabricated by controlling the concentration of SF. The strontium functionalized SF microcarriers showed the sustained release of strontium ion and allowed bone mesenchymal stem cells (BMSCs) to attach, proliferate and secrete extracellular matrix. Furthermore, the strontium functionalized SF microcarriers improved the osteogenic capability of BMSCs in vitro compared with those microcarriers without sustained release of strontium ion. This study presents a valuable approach to fabricate polymeric microcarriers with the capability of sustained release of strontium ion that show potential in bone tissue engineering applications.


Assuntos
Fibroínas , Diferenciação Celular , Osteogênese , Porosidade , Estrôncio , Engenharia Tecidual , Tecidos Suporte
16.
Mater Sci Eng C Mater Biol Appl ; 128: 112359, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474906

RESUMO

Lipid metabolism in macrophages has been increasingly emphasized in exerting an anti-inflammatory effect and accelerating fracture healing. 12-lipoxygenase (12-LOX) is expressed in several cell types, including macrophages, and oxidizes polyunsaturated fatty acids (PUFAs) to generate both pro- and anti-inflammatory lipid mediators, of which the n-3 PUFAs play an important part in tissue homeostasis/fibrosis. Although mechanical factor regulates the lipid metabolic axis of inflammatory cells, specifically matrix stiffness influences macrophages metabolic responses, little is known about how matrix stiffness affects the 12-LOX-mediated early inflammation in bone repair. In the present study, demineralized bone matrix (DBM) scaffolds with different matrix stiffness were constructed by controlling the duration of decalcification (0 h (control), 1 h (high), 12 h (medium), and 5 d (low)) to repair the defected rat skull. The expression of inflammatory cytokines and macrophages polarization were analyzed. The lipid metabolites and lipid mediators' biosynthesis by matrix stiffness-regulated were further detected. The results showed that the low matrix stiffness could polarize macrophages into an anti-inflammatory phenotype, promote the expression of anti-inflammatory cytokines and specialized pro-resolving lipid mediators (SPMs) biosynthesis beneficial for the osteogenesis of mesenchymal stem cells (MSCs). After treated with ML355, the expression of anti-inflammatory cytokines/proteins and SPMs biosynthesis in macrophages cultured on low-matrix stiffness scaffolds were repressed, and there were almost no statistical differences among all groups. Findings from this study support that matrix stiffness regulates bone repair by modulating 12-LOX-mediated early inflammation, which suggest a direct mechanical impact of matrix stiffness on macrophages lipid metabolism and provide a new insight into the clinical application of SPMs for bone regeneration.


Assuntos
Araquidonato 12-Lipoxigenase , Células-Tronco Mesenquimais , Animais , Regeneração Óssea , Inflamação , Osteogênese , Ratos
17.
Shanghai Kou Qiang Yi Xue ; 30(3): 253-257, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34476440

RESUMO

PURPOSE: To investigate the effects of extracellular matrix stiffness on proliferation and osteogenic differentiation of dental pulp stem cells (DPSCs) in polydimethylsiloxane (PDMS)-based cell culture substrate model. METHODS: The premolars removed during orthodontic treatment in Changzhou NO.2 People's Hospital were collected for DPSCs culture. PDMS matrix membranes were prepared, and divided into three groups according to the different stiffness degrees, group A (binder/hardener: 10∶1; 135 kPa), group B (binder/hardener: 20∶1; 54 kPa), and group C (binder/hardener: 30∶1; 16 kPa). Group free from PDMS was set as control group. Thereafter, DPSCs cells were cultured on PDMS matrix, and various indexes were detected. The proliferation rate of DPSCs was detected by CCK-8, the osteogenic differentiation of DPSCs was detected by alizarin red staining, and the protein expression levels of osteocalcin(OCN), RUNX2, Wnt1 and ß-catenin were detected by Western blot. The data were processed with SPSS 22.0 software package. RESULTS: Alizarin red staining showed that DPSCs cells in group A had obvious morphological changes, and the cell arrangement showed obvious orientation, its morphology gradually changed from polygon and spindle shape to square shape, and calcified nodules were also observed. The number of calcified nodules among four groups were the most in the group A, followed by group B and group C, which was the lowest in control group, with significant difference (P<0.05). The cell proliferation rate and the expression of OCN, RUNX2, Wnt1 and ß-catenin were the highest in group A, followed by group B and group C, which was the lowest in control group, with significant difference(P<0.05). CONCLUSIONS: The extracellular matrix with high stiffness may promote the proliferation and osteogenic differentiation of DPSCs by activating Wnt/ß-catenin signaling pathway, which may provide a theoretical basis for periodontal tissue engineering.


Assuntos
Polpa Dentária , Osteogênese , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dimetilpolisiloxanos , Matriz Extracelular , Humanos , Células-Tronco
18.
Shanghai Kou Qiang Yi Xue ; 30(3): 258-262, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34476441

RESUMO

PURPOSE: This study aimed at exploring the effect of berberine (C20H18NO4) on osteogenic differentiation of rat adipose-derived stem cells(ADSCs) and clarifying the related mechanism. METHODS: ADSCs were subjected to 5, 10, 20 µmol/L berberine culture solution. The untreated ADSCs were set as the control group. Cell proliferation activity was determined by MTT method. Alkaline phosphatase (ALP) staining, semi-quantitative assay and alizarin red staining (ARS) were applied to analyze the effect of berberine on osteogenic differentiation of ADSCs. The phosphorylation level of c-Jun amino terminal kinase (JNK) protein was tested by Western blot. Runx2, OCN were tested by Western blot before and after application of JNK pathway inhibitor SP600125. SPSS 22.0 software package was used for statistical analysis. RESULTS: There was no significant difference on cell proliferation activity of ADSCs treated with 5, 10 and 20 µmol/L berberine at 1, 3 and 7 day(P>0.05). ALP staining and ARS staining in groups treated by berberine were significantly darker than those of the control group, and ALP protein secretion in the experimental group was significantly up-regulated (P<0.05). The phosphorylation level of JNK was increased after treated with 10 µmol/L berberine culture medium. The expression of osteogenic related proteins Runx2 and OCN was up-regulated in the experimental group. After inhibition of JNK signaling pathway, the expression of Runx2 and OCN was down-regulated. CONCLUSIONS: Berberine has no effect on cell proliferation of ADSCs, and can up-regulate osteogenic differentiation of ADSCs through activation of JNK signaling pathway.


Assuntos
Berberina , Osteogênese , Animais , Berberina/farmacologia , Diferenciação Celular , Células Cultivadas , Sistema de Sinalização das MAP Quinases , Ratos , Células-Tronco
19.
Niger J Clin Pract ; 24(9): 1366-1372, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34531351

RESUMO

Objective: We aimed to investigate the effectiveness of the liquid PRF-DBBM mixture on new bone formation in maxillary sinus augmentation. Material and Methods: Seven patients requiring two-stage bilateral maxillary sinus augmentation were included in the study. The patients were selected according to the criteria of having an alveolar bone height of at least 2 mm in the atrophic region. The elevated sinus cavities were randomly grafted with DBBM + liquid PRF (test) or DBBM alone (control) in a split-mouth design. Bone samples were collected during implant surgery with a trephine bur for histomorphometric evaluation after 4 months. Results: In the control group, the newly formed bone was 39.49%, the mature bone was 15.66%, the residual graft was 15.62%, and the fibrous tissue ratio 28.59%, while in the test group, the newly formed bone (NFB) was 45.95%, the mature bone was 14.40%, the residual graft was 10.32%, and the fibrous tissue was 29.31%. No statistically significant difference was found between the groups in terms of the parameters studied (p > 0.05). The mean osteocalcin score in the control group was 2.70 ± 0.39, while it was 2.81 ± 0.36 in the test group. There was no statistically significant difference between the averages of osteocalcin scores of the groups (p > 0.05). Conclusion: The results of our study showed that DBBM is a reliable graft material for maxillary sinus augmentation even in the early period. Combining of DBBM with liquid-PRF contributed to new bone formation over a four-month period, but this contribution was not statistically significant.


Assuntos
Substitutos Ósseos , Fibrina Rica em Plaquetas , Levantamento do Assoalho do Seio Maxilar , Animais , Bovinos , Humanos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Minerais , Boca , Osteogênese
20.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 37(9): 815-820, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34533129

RESUMO

Objective To investigate the effect of salvianolic acid B (SalB) on the proliferation, migration and differentiation of human gingival mesenchymal stem cells (hGMSCs). Methods The hGMSCs were isolated and cultured, and the expressions of CD73, CD90, CD34, and CD45 were detected by flow cytometry; logarithmic phase cells were selected and hGMSCs were treated with 0, 5, 10 µmol/L SalB for 24 hours. The proliferation activity of cells in each group was detected by CCK-8 assay, the migration ability of cells was detected by TranswellTM assay and scratch test, and the osteogenic differentiation ability and the adipogenic differentiation ability were detected by alkaline phosphatase (ALP) staining and oil red O staining, respectively; the mRNA and protein expressions of cell differentiation proteins and genes as well as proteins related to the PI3K/AKT signal pathway were detected by Real-time quantiative PCR and Western blotting. Results The proliferation and migration ability of SalB-treated hGMSCs were significantly increased in a dose-dependent manner; the ability of osteogenic differentiation of hGMSCs and the expressions of osteogenesis associated proteins and PI3K/AKT signal pathway related proteins were up-regulated, while the adipogenic differentiation decreased, and the expression of adipogenesis related proteins was significantly down-regulated. Conclusion SalB promotes the proliferation, migration, and osteogenic differentiation of hGMSCs and inhibits the adipogenic differentiation, which may be related to the activation of PI3K/AKT signal pathway.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Benzofuranos , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética
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