Human Osteoblast-like MG-63 Cells Research Articles

Biological Evaluation of Polyvinyl Alcohol Hydrogels Enriched by Hyaluronic Acid and Hydroxyapatite.

This study aimed to develop polyvinyl alcohol (PVA) -based scaffold enriched with hyaluronic acid (HA) and hydroxyapatite (HAp) using physical crosslinking by freezing–thawing method. We accomplished biological evaluation of scaffolds, swelling degree, bioactivity assessment, and hemolytic test. The results showed that all types of scaffolds should be safe for use in the human body. The culturing of human osteoblast-like cells MG-63 and their proliferation showed better adhesion of cells due to the presence of HA and confirmed better proliferation depending on the amount of HAp. This paper gives the optimal composition of the scaffold and the optimal amount of the particular components of the scaffold. Based on our results we concluded that the best PVA/HA/HAp combination is in the ratio 3:1:2.

In vitro and in vivo osteogenesis of gelatin-modified calcium silicate cement with washout resistance.

The purpose of this study was to evaluate the physicochemical properties and the in vitro and in vivo osteogenesis of the newly developed calcium silicate containing 5wt% gelatin (CSG) cement compared with calcium silicate (CS) and calcium sulfate hemihydrate (CSH) cements. In addition to the phase composition and microstructure, washout resistance, setting time, and diametral tensile strength of the bone cements were also performed. In vitro examination of cell growth, differentiation, and mineralization were performed with macrophage cell line (RAW 264.7), MG63 human osteoblast-like cells, and human mesenchymal stem cells (hMSCs). The mini-pig model with mandibular alveolar bone defect was used to assess the in vivo function of cement. Histological and histomorphometric assessments were performed at 6 and 12weeks after implantation. The results indicated that the CS and CSG powders were mainly composed of poorly crystalline β-dicalcium silicate, and the irregular CSH powders had a highly crystalline phase. After setting, the product of CS and CSG was calcium-silicate-hydrate gel and CSH exhibited a plate-like gypsum crystal structure. The setting time of CS, CSG, and CSH was 19, 35, and 10min, respectively. Gelatin effectively improved the washout resistance and diametral tensile strength of CS from 2.4MPa to 3.4MPa, while CSH had no washout resistance and its strength was 7.6MPa. The osteogenic activity of MG63 and hMSC cells on the CSG cement surface was consistently shown to be significantly higher than that on the CSH cement surface. Interestingly, CS and CSG cements exhibited lower macrophage expression compared to CSH cements. Twelve week after implantation, the amount of new bone in the defect area of the CS group was slightly higher than that of the CSG and CSH groups. It is concluded that CSG cement had improved anti-washout performance, favorable osteogenesis in vitro and in vivo, which was beneficial for clinical application.

Preparation of high-strength Co−Cr−Mo alloy rods via hot-caliber rolling

Co−Cr−Mo alloys have various remarkable properties, and their use has been extended in biomedical applications in recent times. In this study, small-diameter Co−Cr−Mo alloy rods, which can be used in spinal instrumentation surgery, were prepared using a developed manufacturing system that enables hot-caliber rolling immediately after the induction heating of a rod workpiece. The effects of rolling temperature (850−1150 °C) and the amount of deformation (up to 0.45 in equivalent strain) on the microstructure, mechanical properties, and cytocompatibility of the rods were examined to determine the processing−microstructure−property relationship and to optimize the processing parameters. The microstructural evolution, which was found to be associated with grain refinement due to the simultaneous dynamic recrystallization (DRX) and accumulation of lattice defects during hot-caliber rolling, significantly strengthened the alloy and maintained the ductility. Bi-directional deformation during hot-caliber rolling at higher rolling temperatures enhanced the DRX, thus realizing uniformly distributed fine grains without preferential orientations, which resulted in the homogeneous mechanical properties of the obtained rods. Consequently, an enhanced strength−ductility combination, which was superior to those obtained in the existing literature, was achieved. Moreover, the cytocompatibility experiments using human MG-63 osteoblast-like cells at various intervals (3, 6, and 10 days) revealed a limited detrimental influence on the cell proliferation and cell migration on the sample hot-rolled at 1150 °C. The developed manufacturing system can be employed for the fabrication of high-strength Co−Cr−Mo alloy rods with high durability, and it can be implemented in low-profile systems for spinal instrumentation surgery.

Preparation of High-Strength Co-Cr-Mo Alloy Rods Via Hot-Caliber Rolling

Co-Cr-Mo alloys have various remarkable properties and in recent times their use has been extended in biomedical applications in recent times. In this study, small-diameter Co-Cr-Mo alloy rods, which can be used in spinal instrumentation surgery, were prepared using a developed manufacturing system that enables hot-caliber rolling immediately after the induction heating of a rod workpiece. The effects of rolling temperature (850-1150 °C) and the amount of deformation (up to 0.45 in equivalent strain) on the microstructure, mechanical properties, and cytocompatibility of the rods were examined to determine the processing-microstructure-property relationship and to optimize the processing parameters. The microstructural evolution, which was found to be associated with grain refinement due to the simultaneous dynamic recrystallization (DRX) and accumulation of lattice defects during hot-caliber rolling, significantly strengthened the alloy and maintained the ductility. Bi-directional deformation during hot-caliber rolling at higher rolling temperatures enhanced the DRX, thus realizing uniformly distributed fine grains without preferential orientations, which resulted in the homogeneous mechanical properties of the obtained rods. Consequently, an enhanced strength-ductility combination, which was superior to those obtained in the existing literature, was achieved. Moreover, the cytocompatibility experiments using human MG-63 osteoblast-like cells at various intervals (3, 6, and 10 days) revealed a limited detrimental influence on the cell proliferation and cell migration on the sample hot-rolled at 1150 °C. The developed manufacturing system can be employed for the fabrication of high-strength Co-Cr-Mo alloy rods with high durability, and it can be implemented in low-profile systems for spinal instrumentation surgery.

The Mechanical Properties, Secondary Structure, and Osteogenic Activity of Photopolymerized Fibroin.

Previously, we have described the preparation of a novel fibroin methacrylamide (FbMA), a polymer network with improved functionality, capable of photocrosslinking into Fb hydrogels with elevated stiffness. However, it was unclear how this new functionality affects the structure of the material and its beta-sheet-associated crystallinity. Here, we show that the proposed method of Fb methacrylation does not disturb the protein’s ability to self-aggregate into the stable beta-sheet-based crystalline domains. Fourier transform infrared spectroscopy (FTIR) shows that, although the precursor ethanol-untreated Fb films exhibited a slightly higher degree of beta-sheet content than the FbMA films (46.9% for Fb-F-aq and 41.5% for FbMA-F-aq), both materials could equally achieve the highest possible beta-sheet content after ethanol treatment (49.8% for Fb-F-et and 49.0% for FbMA-F-et). The elasticity modulus for the FbMA-F-et films was twofold higher than that of the Fb-F-et as measured by the uniaxial tension (130 ± 1 MPa vs. 64 ± 6 MPa), and 1.4 times higher (51 ± 11 MPa vs. 36 ± 4 MPa) as measured by atomic force microscopy. The culturing of human MG63 osteoblast-like cells on Fb-F-et, FbMA-F-et-w/oUV, and FbMA-F-et substrates revealed that the photocrosslinking-induced increment of stiffness increases the area covered by the cells, rearrangement of actin cytoskeleton, and vinculin distribution in focal contacts, altogether enhancing the osteoinductive activity of the substrate.

Aucubin exerts anti-osteoporotic effects by promoting osteoblast differentiation.

Osteoporosis is a metabolic disease characterized by reduced osteoblast differentiation and proliferation. Oxidative stress plays a role in the pathogenesis of osteoporosis. Aucubin (AU), an iridoid glycoside, was previously shown to promote osteoblast differentiation. We investigated the effects of AU on MG63 human osteoblast-like cells treated with dexamethasone (Dex) or hydrogen peroxide (H2O2) to induce oxidative damage. AU protected MG63 cells against apoptosis, and promoted increased expression of cytokines associated with osteoblast differentiation, including collagen I, osteocalcin (OCN), osteopontin (OPN), and osterix. In Dex- and H2O2-treated MG63 cells, AU also enhanced the expression of anti-oxidative stress-associated factors in the nuclear respiratory factor 2 signaling pathway, including superoxide dismutases 1 and 2, heme oxygenases 1 and 2, and catalase. In vivo, using a Dex-induced mouse model of osteoporosis, AU promoted increased cortical bone thickness, increased bone density, and tighter trabecular bone. Additionally, it stimulated an increase in the expression of collagen I, OCN, OPN, osterix, and phosphorylated Akt and Smads in bone tissue. Finally, AU stimulated the expression of cytokines associated with osteoblast differentiation in bone tissue and serum. Our data indicate AU may have therapeutic efficacy in osteoporosis.

Repeated Exposure of Nanostructured Titanium to Osteoblasts with Respect to Peri-Implantitis.

Titanium offers excellent biocompatibility and extraordinary mechanical properties. As a result, it is used as a material for dental implants. Implants infected by peri-implantitis can be cleaned for successful re-osseointegration. Optimal surface properties, such as roughness and wettability, have a significant impact on cell adhesion. The aim of this study was to evaluate the adhesion and proliferation of osteoblasts on the surface of repeatedly cleaned nanostructured titanium samples. Human osteoblast-like cells MG-63 were seeded on nanostructured titanium specimens manufactured from rods produced by the equal channel angular pressing. For surface characterization, roughness and wettability were measured. Cell adhesion after 2 h as well as cell proliferation after 48 h from plating was assessed. We have found that this repeated cleaning of titanium surface reduced cell adhesion as well as proliferation. These events depend on interplay of surface properties, such as wettability, roughness and topography. It is difficult to distinguish which factors are responsible for these events and further investigations will be required. However, even after the several rounds of repeated cleaning, there was a certain rate of adhesion and proliferation recorded. Therefore the attempts to save failing implants by using in situ cleaning are promising.

Comparison the effects of chitosan and hyaluronic acid-based thermally sensitive hydrogels containing rosuvastatin on human osteoblast-like MG-63 cells.

Background and purpose:Bone regeneration can be accelerated by localized delivery of statins. Here, we aimed to evaluate the effect of two thermosensitive hydrogels containing rosuvastatin (RSV) on proliferation and differentiation of human osteoblast-like MG-63 cells.Experimental approach:Firstly, chitosan (CTS)/glycerophosphate (GP)/gelatin (G) thermosensitive hydrogel was prepared and characterized based on rheological properties, in vitro erosion, and release pattern of RSV and then the optimized mixture was loaded with nanoparticles containing RSV(NRSV). Secondly, the effect of NRSV-embedded in CTS/GP/G on cell viability, alkaline phosphate activity, and cell calcification was evaluated using MG-63 cells and compared with RSV-embedded into hyaluronic acid (HA)/Pluronic® F127 (PF127) hydrogel.Findings / Results:CTS/GP mixtures with 1 and 1.5 % gelatin existing in solution with low viscosity at 4 °C were solidified at 32-34 °C while the mixture containing 2% gelatin was jellified at room temperature. The gelation times of CTS/GP/G with 1 and 1.5% gelatin were 72 and 44 s, respectively. The hydrogel containing 3% w/v NRSV was also converted to a semisolid upon increasing the temperature to 33-36 °C. Due to the higher gel strength of CTS/GP/G compared to HA/PF127 hydrogel, the release rate of RSV from the NRSV-embedded CTS/GP/G hydrogel was significantly slower than that of HA/PF127 system. As revealed by alkaline phosphatase and mineralization assays, NRSV-embedded in CTS/GP/G hydrogel had the most promotive effect on differentiation of osteoblasts among other mixtures.Conclusion and implication:NRSV-embedded in CTS/GP/G hydrogel could be efficiently used in the future for bone defects such as osteoporosis and bone fractures.

The effects of mumie extract on cell proliferation and enzyme expression of human osteoblast-like cells (MG63)

Background: Mumie, as an inorganic and semi-solid herbal substance, could be obtained from crevice caves and is used for bone diseases in traditional medicine. This study investigated the effects of this substance on the expression of bone alkaline phosphatase (BALP) enzyme as well as proliferation and mortality rates of MG63 human osteoblast-like cells. Materials and methods: The MG63 cells were cultured and the effect of 100, 200 and 300 μg/ml of mumie extract on cell viability were compared with zoledronic acid and estradiol valerate as positive controls, as well as with MG63 cells alone as the negative control group. The activity rate of the BALP enzyme was also assessed. Results: During 48 hours of the study period, the concentrations of 100 and 200μg/ml of mumie extract increased the proliferation rate and decreased the mortality rate of MG63 cells significantly; however, the concentration of 300μg/ml decreased the proliferation rate and increased the mortality rate of the cells. Also, BALP enzyme expression was slightly affected by 100 and 200 μg/ml of mumie extract whilst it was significantly decreased by the concentration of 300 μg/ml. Conclusion: This study showed that mumie extract has an increasing effect on proliferation rate and a decreasing effect on the mortality rate of osteoblast cells in low concentrations; however, the higher concentrations of this substance could be toxic and effect inversely.

Cinnamon-flavored electronic cigarette liquids and aerosols induce oxidative stress in human osteoblast-like MG-63 cells

As noncombustible nicotine delivery devices, electronic cigarettes (e-cigarettes) are the most popular tobacco product among youth. The widespread popularity of e-cigarettes combined with possible health consequences suggest a need to further research health hazards associated with e-cigarette use. Since conventional tobacco use is a risk factor for osteoporosis, this study investigates the impact of nicotine-free, cinnamon-flavored e-cigarette liquid (e-liquid) on bone-forming osteoblasts compared to flavorless e-liquid. Human tumor-derived osteoblast-like MG-63 cells were exposed for 24 h or 48 h to 0.0.4 %, 0.04 %, 0.4 % or 1 % of unvaped e-liquid or 0.0025 %, 0.025 %, 0.25 %, 1 % or 2.5 % of aerosol condensate in addition to a culture medium only control. Changes in cell viability were assessed by MTT assay, and the expression of a key bone protein, collagen type I, was analyzed by immunofluorescence. Production of reactive oxygen species (ROS) was detected by fluorometry to assess oxidative stress. Cell viability decreased in a dose-dependent manner, and ROS production increased, which was most pronounced with cinnamon-flavored e-liquids. There were no detectable changes in collagen type I protein following exposure to any of the aerosol condensates. This study demonstrates osteoblast-like cells are sensitive to both e-liquids and aerosol condensates and suggests the cytotoxicity of cinnamon-flavored e-liquids might be associated with oxidative stress rather than changes in collagen type I protein expression. This in vitro study provides insight into the potential impacts of e-cigarette use on bone cells.

In vivo delivery of VEGF RNA and protein to increase osteogenesis and intraosseous angiogenesis

Deficient bone vasculature is a key component in pathological conditions ranging from developmental skeletal abnormalities to impaired bone repair. Vascularisation is dependent upon vascular endothelial growth factor (VEGF), which drives both angiogenesis and osteogenesis. The aim of this study was to examine the efficacy of blood vessel and bone formation following transfection with VEGF RNA or delivery of recombinant human VEGF165 protein (rhVEGF165) across in vitro and in vivo model systems. To quantify blood vessels within bone, an innovative approach was developed using high-resolution X-ray computed tomography (XCT) to generate quantifiable three-dimensional reconstructions. Application of rhVEGF165 enhanced osteogenesis, as evidenced by increased human osteoblast-like MG-63 cell proliferation in vitro and calvarial bone thickness following in vivo administration. In contrast, transfection with VEGF RNA triggered angiogenic effects by promoting VEGF protein secretion from MG-63VEGF165 cells in vitro, which resulted in significantly increased angiogenesis in the chorioallantoic (CAM) assay in ovo. Furthermore, direct transfection of bone with VEGF RNA in vivo increased intraosseous vascular branching. This study demonstrates the importance of continuous supply as opposed to a single high dose of VEGF on angiogenesis and osteogenesis and, illustrates the potential of XCT in delineating in 3D, blood vessel connectivity in bone.

Development and Biocompatibility of Collagen-Based Composites Enriched with Nanoparticles of Strontium Containing Mesoporous Glass.

In the last years bone tissue engineering has been increasingly indicated as a valid solution to meet the challenging requirements for a healthy bone regeneration in case of bone loss or fracture. In such a context, bioactive glasses have already proved their great potential in promoting the regeneration of new bone tissue due to their high bioactivity. In addition, their composition and structure enable us to incorporate and subsequently release therapeutic ions such as strontium, enhancing the osteogenic properties of the material. The incorporation of these inorganic systems in polymeric matrices enables the formulation of composite systems suitable for the design of bone scaffolds or delivery platforms. Among the natural polymers, type I collagen represents the main organic phase of bone and thus is a good candidate to develop biomimetic bioactive systems for bone tissue regeneration. However, alongside the specific composition and structure, the key factor in the design of new biosystems is creating a suitable interaction with cells and the host tissue. In this scenario, the presented study aimed at combining nano-sized mesoporous bioactive glasses produced by means of a sol–gel route with type I collagen in order to develop a bioactive hybrid formulation suitable for bone tissue engineering applications. The designed system has been fully characterized in terms of physico-chemical and morphological analyses and the ability to release Sr2+ ions has been studied observing a more sustained profile in presence of the collagenous matrix. With the aim to improve the mechanical and thermal stability of the resulting hybrid system, a chemical crosslinking approach using 4-star poly (ethylene glycol) ether tetrasuccinimidyl glutarate (4-StarPEG) has been explored. The biocompatibility of both non-crosslinked and 4-StarPEG crosslinked systems was evaluated by in vitro tests with human osteoblast-like MG-63 cells. Collected results confirmed the high biocompatibility of composites, showing a good viability and adhesion of cells when cultured onto the biomaterial samples.

Fermented Oyster Extract Promotes Osteoblast Differentiation by Activating the Wnt/β-Catenin Signaling Pathway, Leading to Bone Formation.

The Pacific oyster, Crassostrea gigas, is well-known as a nutritious food. Recently, we revealed that fermented extract of C. gigas (FO) inhibited ovariectomy-induced osteoporosis, resulting from suppression of osteoclastogenesis. However, since the beneficial effect of FO on osteogenesis is poorly understood, it was examined in mouse preosteoblast MC3T3-E1 cells, human osteosarcoma MG-63 osteoblast-like cells, and zebrafish larvae in this study. We found that FO increased mitochondrial activity from days 1 to 7; however, total cell number of MC3T3-E1 cells gradually decreased without any change in cell viability, which suggests that FO stimulates the differentiation of MC3T3-E1 cells. FO also promoted the expression of osteoblast marker genes, including runt-related transcription factor 2 (mRUNX2), alkaline phosphatase (mALP), collagen type I α1 (mCol1α1), osteocalcin (mOCN), osterix (mOSX), bone morphogenetic protein 2 (mBMP2), and mBMP4 in MC3T3-E1 cells accompanied by a significant increase in ALP activity. FO also increased nuclear translocation of RUNX2 and OSX transcription factors, ALP activity, and calcification in vitro along with the upregulated expression of osteoblast-specific marker proteins such as RUNX2, ALP, Col1α1, OCN, OSX, and BMP4. Additionally, FO enhanced bone mineralization (calcein intensity) in zebrafish larvae at 9 days post-fertilization comparable to that in the β-glycerophosphate (GP)-treated group. All the tested osteoblast marker genes, including zRUNX2a, zRUNX2b, zALP, zCol1a1, zOCN, zBMP2, and zBMP4, were also remarkably upregulated in the zebrafish larvae in response to FO. It also promoted tail fin regeneration in adult zebrafish as same as the GP-treated groups. Furthermore, not only FO positively regulate β-catenin expression and Wnt/β-catenin luciferase activity, but pretreatment with a Wnt/β-catenin inhibitor (FH535) also significantly decreased FO-mediated bone mineralization in zebrafish larvae, which indicates that FO-induced osteogenesis depends on the Wnt/β-catenin pathway. Altogether, the current study suggests that the supplemental intake of FO has a beneficial effect on osteogenesis.

Silicalite-1 Layers as a Biocompatible Nano- and Micro-Structured Coating: An In Vitro Study on MG-63 Cells.

Silicalite-1 is a purely siliceous form of zeolite, which does not contain potentially harmful aluminum in its structure as opposed to ZSM-5 aluminosilicate types of zeolite. This paper reports on a study of a silicalite-1 film, deposited on a silicon Si(100) substrate, as a potential anti-corrosive and biocompatible coating for orthopaedic implants. Silicalite-1 film was prepared in situ on the surface of Si(100) wafers using a reaction mixture of tetrapropyl-ammonium hydroxide (TPAOH), tetraethyl-orthosilicate (TEOS), and diH2O. The physico-chemical properties of the obtained surface were characterized by means of X-ray photoelectron spectroscopy, water contact angle measurement, atomic force microscopy, and scanning electron microscopy. The biocompatibility was assessed by interaction with the MG-63 cell line (human osteosarcoma) in terms of cell adhesion, morphology, proliferation, and viability. The synthesized silicalite-1 film consisted of two layers (b- and a, b-oriented crystals) creating a combination of micro- and nano-scale surface morphology suitable for cell growth. Despite its hydrophobicity, the silicalite-1 film increased the number of initially adhered human osteoblast-like MG-63 cells and the proliferation rate of these cells. The silicalite-1 film also improved the cell viability in comparison with the reference Si(100) substrate. It is therefore a promising candidate for coating of orthopaedic implants.

Biosynthesis and characterization of zinc oxide nanoparticles from Artemisia annua and investigate their effect on proliferation, osteogenic differentiation and mineralization in human osteoblast-like MG-63 Cells

The Biocompatibility and stability of nanoparticles using plants have been widely investigated due to its applications in the biomedical industry. Currently, there is a growing interest in nanoparticles in bone remodelling. Artemisia annua is an herbal plant commonly used in the treatment of various ailments. This study investigated the zinc oxide nanoparticles (ZnO NPs) using the green synthesis technique from A. annua and the effects of A. annua ZnO-NPs on osteoblast differentiation and inhibition of osteoclast formation. The formulated ZnO-NPs from A. annua were characterized by using various spectroscopic and microscopic methods Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV–Visible spectroscopy. The disc diffusion method was adopted to test the antimicrobial efficacy of ZnO-NPs. The viability of MG-63 cells were assayed by MTT test and Osteogenic-related assays like Real-time PCR and Mineralization assay were adopted to determine the effects of A. annua ZnO-NPs on the multiplication and differentiation of human osteoblast-like MG-63 cells. The characterization of A. annua ZnO-NPs revealed the crystalline nature with high zinc content and the presence of bioactive compounds from A. annua extract. The synthesized A. annua ZnO-NPs indicate significant antimicrobial potential. Besides, A. annua ZnO-NPs enhanced the proliferation, differentiation, and mineralization without causing significant cytotoxic impact on MG-63 cells. These effects indicate that A. annua ZnO-NPs can both stimulate bone formation via the differentiation of MG-63 cells. Hence, it was concluded that A. annua ZnO-NPs can be a promising agent for the treatment of bone deformities and bone-related diseases, however further research also required to explore the clear mechanism of A. annua ZnO-NPs in the formation and differentiation of MG-63 cells.

A Vitronectin-Derived Bioactive Peptide Improves Bone Healing Capacity of SLA Titanium Surfaces.

In this study, we evaluated early bone responses to a vitronectin-derived, minimal core bioactive peptide, RVYFFKGKQYWE motif (VnP-16), both in vitro and in vivo, when the peptide was treated on sandblasted, large-grit, acid-etched (SLA) titanium surfaces. Four surface types of titanium discs and of titanium screw-shaped implants were prepared: control, SLA, scrambled peptide-treated, and VnP-16-treated surfaces. Cellular responses, such as attachment, spreading, migration, and viability of human osteoblast-like HOS and MG63 cells were evaluated in vitro on the titanium discs. Using the rabbit tibia model with the split plot design, the implants were inserted into the tibiae of four New Zealand white rabbits. After two weeks of implant insertion, the rabbits were sacrificed, the undecalcified specimens were prepared for light microscopy, and the histomorphometric data were measured. Analysis of variance tests were used for the quantitative evaluations in this study. VnP-16 was non-cytotoxic and promoted attachment and spreading of the human osteoblast-like cells. The VnP-16-treated SLA implants showed no antigenic activities at the interfaces between the bones and the implants and indicated excellent bone-to-implant contact ratios, the means of which were significantly higher than those in the SP-treated implants. VnP-16 reinforces the osteogenic potential of the SLA titanium dental implant.

Incorporation of Glycine max Merrill Extract into Layered Double Hydroxide through Ion-Exchange and Reconstruction.

We incorporated extract of Glycine max Merrill (GM), which is generally known as soybean, into a layered double hydroxide (LDH) nanostructure through two different methods, ion-exchange and reconstruction. Through X-ray diffraction, field-emission scanning electron microscopy, and zeta-potential measurement, GM moiety seemed to be simply attached on the surface of LDH by ion-exchange process, while the extract could be incorporated in the inter-particle pore of LDHs by reconstruction reaction. The quantification exhibited that both incorporation method showed comparable extract loading capacity of 15.6 wt/wt% for GM-LDH hybrid prepared by ion-exchange (GML-I) and 18.6 wt/wt% for GM-LDH hybrid by reconstruction (GML-R). On the other hand, bioactive substance in both GM-LDH hybrids, revealed that GML-R has higher daidzein content (0.0286 wt/wt%) compared with GML-I (0.0108 wt/wt%). According to time-dependent daidzein release, we confirmed that GML-R showed pH dependent daidzein release; a higher amount of daidzein was released in pH 4.5 physiological condition than in pH 7.4, suggesting the drug delivery potential of GML-R. Furthermore, alkaline phosphatase activity and collagen fiber formation on human osteoblast-like MG-63 cells displayed that GML-R had superior possibility of osteoblast differentiation than GML-I. From these results, we concluded that reconstruction method was more effective for extract incorporation than ion-exchange reaction, due to its pH dependent release property and alkaline phosphatase activity.

Effect of coral Goniopora Sp scaffold application on human osteoblast-like MG-63 cell activity in vitro

Effect of coral Goniopora Sp scaffold application on human osteoblast-like MG-63 cell activity in vitro

Novel multicomponent organic-inorganic WPI/gelatin/CaP hydrogel composites for bone tissue engineering.

The present work focuses on the development of novel multicomponent organic-inorganic hydrogel composites for bone tissue engineering. For the first time, combination of the organic components commonly used in food industry, namely whey protein isolate (WPI) and gelatin from bovine skin, as well as inorganic material commonly used as a major component of hydraulic bone cements, namely α-TCP in various concentrations (0-70 wt%) was proposed. The results showed that α-TCP underwent incomplete transformation to calcium-deficient hydroxyapatite (CDHA) during preparation process of the hydrogels. Microcomputer tomography showed inhomogeneous distribution of the calcium phosphate (CaP) phase in the resulting composites. Nevertheless, hydrogels containing 30-70 wt% α-TCP showed significantly improved mechanical properties. The values of Young's modulus and the stresses corresponding to compression of a sample by 50% increased almost linearly with increasing concentration of ceramic phase. Incomplete transformation of α-TCP to CDHA during preparation process of composites provides them high reactivity in simulated body fluid during 14-day incubation. Preliminary in vitro studies revealed that the WPI/gelatin/CaP composite hydrogels support the adhesion, spreading, and proliferation of human osteoblast-like MG-63 cells. The WPI/gelatin/CaP composite hydrogels obtained in this work showed great potential for the use in bone tissue engineering and regenerative medicine applications.

Bioactive glass (45S5)-based 3D scaffolds coated with magnesium and zinc-loaded hydroxyapatite nanoparticles for tissue engineering applications

Bioactive glass (BG)-based scaffolds of 45S5 composition covered with hydroxyapatite nanoparticles loaded with Mg2+, Zn2+ and, both Mg2+ and Zn2+ ions, were developed and tested as materials for tissue engineering applications. The scaffolds were prepared by the foam replica technique and mono- and bi-metal loaded and unloaded hydroxyapatite nanoparticles (HA, Zn-HA, Mg-HA and Mg-Zn-HA) were obtained by an adaptation of the wet chemical deposition method. Coating of BG with these nanoparticles was performed by dip-coating to obtain HA-BG, Zn-HA-BG, Mg-HA-BG and Mg-Zn-HA-BG scaffolds.As predictor of the bone bonding ability of the produced scaffolds, in this study we investigated the formation of an apatite layer on the scaffold surfaces in the presence of simulated body fluid. The cytotoxicity and osteogenic properties of the materials in vitro was evaluated using human osteoblast-like MG-63 cell cultures. The mineralization assay following Kokubo’s protocol indicated that bi-metal loaded Mg-Zn-HA-BG scaffolds exhibited higher/faster bioactivity than mono-metal loaded scaffolds while mineralization of HA-BG, Zn-HA-BG and Mg-HA-BG was similar to that of uncoated scaffolds. Moreover, an increase of proliferation of MG-63 cells after 48 h and 7 days was measured by BrdU assays for Mg-Zn-HA-BG scaffolds. In agreement with these results, SEM images confirmed increased interaction between these scaffolds and cells, in comparison to that observed for mono-metal-loaded HA-coated scaffolds. Altogether, the obtained results suggest that nanocrystalline Mg-Zn-HA coatings enhance the biological performance of standard scaffolds of 45S5 BG composition. Thus these novel ion doped HA coated scaffolds are attractive systems for bone tissue engineering.