Viability Of MG-63 Cells Research Articles

Evaluation of the effects of starch on polyhydroxybutyrate electrospun scaffolds for bone tissue engineering applications

Efficient design for bone tissue engineering requires an understanding of the appropriate selection of biomimetic natural or synthetic materials and scalable fabrication technologies. In this research, poly (3-hydroxybutyrate) (PHB) and starch (5-15 wt%) as biological macromolecules were used to fabricate novel biomimetic scaffolds by electrospinning method. SEM results of electrospun scaffolds revealed bead-free nanofibers and three-dimensional homogenous structures with highly interconnected pores. Results of FTIR and Raman demonstrated that there were hydrogen bonds between the two polymers. The tensile strength of scaffolds was significantly improved by adding starch up to 10 wt%, from 3.05 to 15.54 MPa. In vitro degradation and hydrophilicity of the scaffolds were improved with the presence of starch. The viability and proliferation of MG-63 cells and alkaline phosphatase (ALP) activity were remarkably increased in the PHB-starch scaffolds compared to the PHB and control samples. The mineralization and calcium deposition of MG-63 cells were confirmed by alizarin red staining. It is concluded that PHB/starch electrospun scaffold could be a good candidate for bone tissue engineering applications.

Tuning the biomimetic behavior of hybrid scaffolds for bone tissue engineering through surface modifications and drug immobilization

Bone defects arising from injury and/or disease are a common and debilitating clinical lesion. While the development of tissue microenvironments utilizing biomimetic constructs is an emerging approach for bone tissue engineering. In this context, bioactive glass nanoparticles (BGNPs) were embedded within polycaprolactone (PCL) scaffolds. The scaffolds exhibit an engineered unidirectional pore structure which are surface activated via oxygen plasma to allow immobilization of simvastatin (SIM) on the pore surface. Microscopic observation indicated the surface modification did not disturb the lamellar orientation of the pores improving the biomimetic formation of hydroxyapatite. Mathematically modelled release profiles reveal that the oxygen plasma pre-treatment can be utilized to modulate the release profile of SIM from the scaffolds. With the release mechanism controlled by the balance between the diffusion and erosion mechanisms. Computational modelling shows that Human Serum Albumin and Human α2-macroglobulin can be utilized to increase SIM bioavailability for cells via a molecular docking mechanism. Cellular studies show positive MG-63 cell attachment and viability on optimized scaffolds with alkaline phosphatase activity enhanced along with enhanced expression of osteocalcoin biomarker.

Osteosarcoma Cell Growth Inhibition by Isoxanthanol-Nanoparticles through Histone H3 Lysine 27 Trimethylation Downregulation and AMPK Activation.

The present study was aimed to investigate the effect of isoxanthanol-nanoparticles (IXNP) on proliferation of osteosarcoma cells and evaluate the underlying mechanism. In MG-63 and U2-OS cells proliferative potential was reduced significantly (p < 0.05) in dose-dependent manner by IXNP treatment. The IXNP treatment at 15 mg/mL suppressed MG-63 cell viability to 39% and that U2-OS cells to 43% at 48 h. Treatment with IXNP led to a prominent up-regulation of caspases-3 and -9 cleavage compared to untreated cells. Moreover, PARP and Bax levels in the cells showed a remarkable increase on IXNP-treatment in comparison to the control cells. Phosphorylation of AMPKα, expression of p21 and replication of mtDNA was also promoted in MG-63 and U2-OS cells on treatment with IXNP. In MG-63 and U2-OS cells, IXNP-treatment elevated expression of PGC-1α and TFAM while as EED, EZH2, and SUZ12 expression was down-regulated. Thus, IXNP suppress proliferation of osteosarcoma cells through activates AMPK activation and elevation of Histone H3 lysine 27 trimethylation. Therefore, IXNP has therapeutic potential to be developed for treatment of osteosarcoma.

Effect of pH on cisplatin encapsulated zeolite nanoparticles: Release mechanism and cytotoxicity

The present study aims to develop the pH-sensitive zeolite Y nanoparticles for the delivery of cisplatin (CIS). The obtained results showed that CIS was incorporated in the zeolite cavities with a loading capacity of 19.3 ± 0.6–32.4 ± 0.3%, depending on the pH value of the environment, time, and drug concentrations. Furthermore, pH-dependency of CIS release from ZC-NPs was verified by the in vitro drug release assessment. Noticeably, in an acidic environment (pH = 5.4) a faster release of CIS could be observed (93.8 ± 6.8% Vs 50.6 ± 2.4% during 7 days of incubation). Based on the MTT results, the CIS released from ZC-NPs showed a cytotoxic effect. However, not only zeolite nanoparticles were non-cytotoxic, but also the viability of MG63 cells was improved compared to the zeolite-free samples. The advantages of ZC-NPs such as good cytocompatibility, excellent physiological stability, and sustained pH-responsive release properties make it a promising system for the delivery of other chemotherapeutic drugs.

Fabrication of fibrous poly (ɛ‐caprolactone) nano‐fibers containing cerium doped‐bioglasses nanoparticles encapsulated collagen

AbstractNovel nanosized designed ceramic powders, cerium (Ce) doped bioglass (BG) with various doped Ce content, were synthesized by sol–gel method in order to be employed in the development of PCL fibrous scaffold for bone tissue engineering applications. Characterization techniques such as X‐ray diffraction analysis, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy‐dispersive X‐ray spectroscopy were employed to evaluate the developed Ce doped BG powders. The results confirmed successful doping of Ce inside BG structure. 0, 1, 3, and 10 wt% Ce doped 58S BG were successfully encapsulated in the collagen microspheres by water‐in‐oil emulsion method and the average particle size and hydrodynamic diameter of microspheres were determined using scanning electron microscopy and dynamic light scattering analysis, respectively. Next, 0, 1, 3, and 10 wt% Ce doped 58S BG encapsulated collagen microspheres were loaded inside the Poly(ɛ‐caprolactone) fibrous scaffold and their in vitro bioactivity and biocompatibility properties were evaluated. The results of soaking samples in the simulated body fluid showed that all Ce doped 58S BG encapsulated collagen microspheres loaded PCL fibrous scaffold have acceptable bioactivity and apatite formation ability over time. The biocompatibility evaluation of developed scaffolds showed high viability and proliferation of MG63 cells cultured on the surface of 3% Ce doped 58S BG encapsulated collagen microsphere loaded in the PCL fibrous scaffold and its high potential ability for bone tissue engineering applications. These results potentially open new aspects for scaffolds aimed at the regeneration of bone defects.

Zinc oxide nanoparticles from Cassia auriculata flowers showed the potent antimicrobial and in vitro anticancer activity against the osteosarcoma MG-63 cells.

Osteosarcoma (OS) is a foremost mesenchymal bone neoplasm and it can occur at any age with survival rate is nearly 2–8 times lesser in elders than in teenagers. The clinical therapies for cancer treatment have gradually becoming outdated because of the developments of nano-medicine and multi-targeted drug-delivery. In this work, we green synthesized the zinc oxide nanoparticles from the Cassia auriculata flower (AS-ZnONPs) extract and evaluated its antimicrobial and in vitro anticancer potential against the OS MG-63 cells. The synthesized AS-ZnONPs were confirmed and characterized by using UV–vis spectroscopy, XRD, FE-SEM, and photoluminescence techniques. The antimicrobial activity of AS-ZnONPs was studied by disc diffusion technique. The viability of AS-ZnONPs treated MG-63 cells were examined by MTT assay. The apoptotic cells in the AS-ZnONPs treated MG-63 cells were assayed by dual staining. The MMP status of AS-ZnONPs treated cells were tested by Rh-123 staining. The cell adhesion assay was performed to detect the anticancer effects of AS-ZnONPs against MG-63 cells. The results of UV–vis spectroscopy, XRD, FE-SEM, and photoluminescence techniques proved the formation of AS-ZnONPs and it has the hexagonal wurtzite structures. AS-ZnONPs displayed the potent antimicrobial activity against the tested microbial strains. The AS-ZnONPs were appreciably inhibited the cell viability of MG-63 cells. The outcomes of fluorescence staining proved that AS-ZnONPs reduced the MMP and prompted the apoptosis in MG-63 cells. In conclusion, our discoveries demonstrated that the formulated AS-ZnONPs has the potent antimicrobial and in vitro anticancer activity against the MG-63 cells. The AS-ZnONPs could be potent chemotherapeutic agent in the future to treat the OS.

The Effects of Chemical Etching and Ultra-Fine Grain Structure of Titanium on MG-63 Cells Response

In this work, we study the influence of the surface properties of ultrafine grained (UFG) and coarse grained (CG) titanium on the morphology, viability, proliferation and differentiation of osteoblast-like MG-63 cells. Wet chemical etching in H2SO4/H2O2 and NH4OH/H2O2 solutions was used for producing surfaces with varying morphology, topography, composition and wettability. The topography and morphology have been studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The composition was determined by time of flight mass-spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). The results showed that it is possible to obtain samples with different compositions, hydrophilicity, topography and nanoscale or/and microscale structures by changing the etching time and the type of etching solution. It was found that developed topography and morphology can improve spreading and proliferation rate of MG-63 cells. A significant advantage of the samples of the UFG series in comparison with CG in adhesion, proliferation at later stages of cultivation (7 days), higher alkaline phosphatase (ALP) activity and faster achievement of its maximum values was found. However, there is no clear benefit of the UFG series on osteopontin (OPN) expression. All studied samples showed no cytotoxicity towards MG-63 cells and promoted their osteogenic differentiation.

MALAT1 knockdown promoted cell viability and migration of LPS-treated MG-63 cells via sponging miR-212.

Most fractures could heal after treatment, around 5-10 % of patients still develop delayed union and nonunion. Evidence has increasingly shown that abnormal expression of long noncoding RNAs is closely related to the occurrence and development of various diseases including fracture healing. However, evidence regarding the effect of MALAT1 on fracture healing remains limited. In this study, we attempt to explore the role of MALAT1 during the process of femoral neck fracture healing and elucidate the underlying mechanism of this disease. We first detect the expression of lncRNAs in serums from 3 pairs of patients with delayed femoral neck fracture healing and healthy volunteers using lncRNA microarray. And the expression of long noncoding RNA MALAT1 in serums and LPS-treated MG-63 cells was measured using qRT-PCR. CCK-8 assay, cell migration and qRT-PCR were applied to the role of MALAT1 knockdown in LPS-treated MG-63 cells. ELISA was used for the measurement of inflammatory cytokines in serums of patients and healthy volunteers. The bioinformatics analysis and the rescue experiment were devoted to the underlying mechanism. MALAT1 expression was up-regulated in serum of patients with delayed union of femoral neck fracture. MALAT1 knockdown promoted cell viability and migration, reduced inflammation in LPS-treated MG-63 cells. The bioinformatics analysis showed MALAT1 acts as a molecular sponge for miR-212. And SOX6 was a target of miR-212. Besides, MALAT1 knockdown suppressed SOX6 expression via targeting miR-212 in LPS-treated MG-63 cells. These data suggest MALAT1 knockdown promoted the biological behavior of LPS-treated MG-63 cells via sponging miR-212, which may provide a new therapeutic avenue for delayed union of femoral neck fracture.

Improved antibacterial and cellular response of electrets and piezobioceramics.

The bacterial contamination in implants has been recognized as one of the key issues in orthopedics. In this article, a new technique of electrical polarization of various non-piezoelectric and piezoelectric biocompatible ceramics has been explored to develop antibacterial implants. Optimally processed hydroxyapatite (HA), BaTiO3 (BT), CaTiO3 (CT), Na0.5K0.5NbO3 (NKN) and their composites have been used as model biomaterials to verify the concept. The phase evolution analyses and microstructural characterizations were performed for sintered samples. The samples were polarized at polarizing voltage and temperature of 20 kV and 500°C, respectively, for 30 min. The hydrophilicity of polarized surfaces was examined using deionized water and culture media. The polarization induced in-vitro antibacterial study was performed for both, gram positive and gram negative bacteria. The viability of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria reduces significantly on the polarized surfaces. In addition, the influence of polarization on antibacterial response has been explored via various mechanisms such as development of reactive oxygen species (ROS), catalase activity and lipoperoxidation. Furthermore, the cellular response of polarized surfaces was also examined using SaOS2 and MG-63 cells. The viability of SaOS2 and MG-63 cells was observed to increase significantly on negatively polarized surfaces. Overall, the surface treatment enhances the antibacterial response of HA, NKN, BT, CT and their composites surfaces with positive influence on cellular response.

Caffeic acid treatment augments the cell proliferation, differentiation, and calcium mineralization in the human osteoblast-like MG-63 cells

Background: Osteoporosis is an imperative health problem that extremely distresses the public that leads to a higher risk to the bones from both spontaneous and accidental bone fractures. Caffeic acid is a polyphenol compound that happens naturally in numerous vegetables such as coffee beans, potatoes, propolis, olives, and carrots with many pharmacological aids. Objectives: The current study was planned to examine the potential of Caffeic acid in proliferation, differentiation, and calcium mineralization of osteoblast-like MG-63 cells. Materials and Methods: The cell viability of Caffeic acid-supplemented MG-63 cells was examined through the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity test. The mRNA expression of alkaline phosphatase (ALP) and osteocalcin was reviewed through reverse transcription polymerase chain reaction study. The calcium deposition rate in the Caffeic acid-treated MG-63 cells was studied through Alizarin Red S (ARS) staining. Results: The result of the MTT test exposed that the 10 and 20 mg/kg of Caffeic acid supplementation did not show any cytotoxicity to the osteoblast-like MG-63 cells; instead, it helped the viability of MG-63 cells. The expression of ALP is particularly increased in the Caffeic acid-supplemented MG-63 cells, whereas the osteocalcin expression was noticeably diminished. The ARS staining was exhibited that the Caffeic acid treatment was noticeably enhanced the calcium mineralization rate in the osteoblast-like MG-63 cells. Conclusion: Based on the findings of investigation, it was proved that the Caffeic acid treatment was significantly enhanced the cell proliferation, differentiation, and calcium mineralization in the osteoblast-like MG-63 cells. Hence, it was clear that Caffeic acid can be engaged as the potential agent for the purpose of bone regeneration.

Eldecalcitol induces apoptosis and autophagy in human osteosarcoma MG-63 cells by accumulating ROS to suppress the PI3K/Akt/mTOR signaling pathway

Eldecalcitol (ED-71) is a new type of vitamin D analog, and vitamin D has been reported to have therapeutic effects in infectious disease, autoimmune disease, and cancer. However, the anti-cancer effect of ED-71 remains unclear. The objective of this study was to explore the anti-cancer effect of ED-71 in human osteosarcoma cells and to identify the related mechanism. The CCK8 assay results showed that ED-71 inhibited MG-63 cell viability in dose and time dependent manners. Cloning and Transwell invasion assays showed that ED-71 inhibited clonal and invasion ability of MG-63 cells. Flow cytometry results showed ED-71 the G2/M cycle arrest rate, apoptosis, and intracellular ROS. Western blot was used to detect cleaved-caspase-3, Bax, Bcl-2, LC3-II/LC3-I, and P62 levels and the mTOR pathway. The increase of LC3-II and P62 indicated that ED-71 induced the formation of autophagosomes and inhibited autophagy flux. Furthermore, ED-71-induced apoptosis was weakened after adding 3-methyladenine and ED-71-induced early autophagy was weakened by caspase-3 inhibitor (Z-VAD-FMK), which indicated the two processes active each other in the presence of ED-71. Furthermore, N-acetylcysteine (NAC) pretreatment reversed the ED-71-treatment outcomes, including increased apoptosis and autophagy and inhibition of the PI3K/Akt/mTOR pathway. In conclusion, our results reveal that ED-71 induced G2/M arrest, apoptosis and autophagy in MG-63 cells by accumulating ROS to suppress the PI3K/Akt/mTOR signaling pathway

In vitro study: Bond strength, electrochemical and biocompatibility evaluations of TiO2/Al2O3 reinforced hydroxyapatite sol–gel coatings on 316L SS

To improve the biocompatibility and corrosion resistance of 316L SS (Stainless Steel) metal implants, HAp(hydroxyapatite)/TiO2/Al2O3 nanocomposite coating was created using dip sol-gel method sintered at 550 °C. The weight percentage of TiO2+ Al2O3 in these coatings was 20, 30, and 40% wt. In this study, characterization was performed using FTIR (Fourier-Transform Infrared Spectroscopy), XRD, FE-SEM (Field Emission Scanning Electron Microscope), EDS (Energy Dispersive Spectroscopy), DLS (Dynamic Light Scattering), Pull-off, and AFM (Atomic Force Microscopy) analysis. The potentiodynamic polarization and EIS (Electrochemical Impedance Spectroscopy) were performed in the simulated body fluid (SBF) solution. The samples were immersed in SBF solution for 28 days to investigate the ability to form a bone-like layer on the coatings. The amount of calcium and phosphate in the SBF solution and on the coating surface was measured. The MTT assay was performed to examine human MG63 cells viability for various coatings (24 and 72 h). The results showed that the HAp/TiO2/Al2O3 reinforced coatings have the lowest cracks and porosity and have the highest bond strength to the 316L SS substrate (26.5 MPa). Also, the lowest corrosion current density is related to nanocomposite coatings (HAp + 40%wt Al2O3 + TiO2:0.091 μA/cm2), which is pretty low compared to the uncoated substrate (40.35 μA/cm2) or HAp coating (25.26 μA/cm2). The EIS test results showed that in Nyquist curves, the semicircular diameter is more extensive for nanocomposite coatings, which indicates the higher corrosion resistance of these coatings. Cell culture studies showed that the reinforced coatings were non-cytotoxic to human MG63 cell line (HAp + 30%wt Al2O3 + TiO2:99.50% MG63 cell viability), and these coatings have a higher ability to form a bone-like layer than other coatings. However, adding 40% wt TiO2 + Al2O3 negatively affects biocompatibility (HAp + 40%wt Al2O3 + TiO2:87.7% MG63 cell viability). Therefore, HAp + 30%wt(TiO2 + Al2O3) coatings have biocompatibility, adhesion strength, corrosion resistance higher than other coatings, which means that this improved coating has better properties than hydroxyapatite coatings, and this is a new turning point for biocomposite coatings for medical applications.

LL-37-induced caspase-independent apoptosis is associated with plasma membrane permeabilization in human osteoblast-like cells

The host defense peptide LL-37 is active against both gram-positive and gram-negative bacteria, but it has also been shown to reduce human host cell viability. However, the mechanisms behind LL-37-induced human host cell cytotoxicity are not yet fully understood. Here, we assess if LL-37-evoked attenuation of human osteoblast-like MG63 cell viability is associated with apoptosis, and if the underlying mechanism may involve LL-37-induced plasma membrane permeabilization. MG63 cell viability and plasma membrane permeabilization were investigated by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and by measuring lactate dehydrogenase (LDH) release, respectively. Apoptosis was assessed by the terminal deoxynucleotidyl dUTP nick end labeling (TUNEL) assay and Annexin V flow cytometry, and caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage were determined by Western blot. LL-37 (4 and 10 μM) reduced both cell number and cell viability, and these effects were associated with a pro-apoptotic effect demonstrated by positive TUNEL staining and Annexin V flow cytometry. LL-37-induced apoptosis was not coupled to either caspase-3 or PARP cleavage, suggesting that LL-37 causes caspase-independent apoptosis in MG63 cells. Both LL-37 and the well-known plasma membrane permeabilizer Triton X-100 reduced cell viability and stimulated LDH release. Triton X-100-treated cells showed positive TUNEL staining, and the detergent accumulated cells in late apoptosis/necrosis. Similar to LL-37, Triton X-100 caused no PARP cleavage. We conclude that LL-37 promotes caspase-independent apoptosis, and that this effect seems coupled to plasma membrane permeabilization in human MG63 cells.

Dual alloying improves the corrosion resistance of biodegradable Mg alloys prepared by selective laser melting

Abstract Mg alloys have been regarded as revolutionary metallic biomaterials for biodegradable bone implants, but their applications are mainly blocked by the too rapid degradation in physiological environment. This study explores the dual alloying effects of Mn and/or Sn on the performance of Mg alloys prepared by selective laser melting. The observed microstructure indicated remarkable refinement of both the grains and intermetallic phases in the Mn- and/or Sn-containing alloys during the rapid solidification process. Moreover, approximately a half decrease in corrosion rate was observed for AZ61–0.4Mn-0.8Sn alloy with respect to AZ61 alloy. The improved corrosion behavior was primarily due to the enhanced protective effects of surface layers, in which Mn- and/or Sn-rich phases acted as a helpful barrier against medium penetration and thereby alleviated the current exchange with the matrix. In addition, the solute Mn and/or Sn positively shifted the corrosion potential, which also brought about a better corrosion resistance. Furthermore, the strength and hardness of the alloys were also effectively improved and comparable to those of cortical bone. This could be ascribed to the dissolved Mn and/or Sn atoms and the finely dispersed intermetallic phases, which might cause lattice distortion and precipitation hardening. Besides, the Mn- and/or Sn-containing alloys showed good cytocompatibility as indicated by the normal morphology and increased viability of MG-63 cells. These findings suggest that the developed AZ61-Mn-Sn alloy is a promising candidate for biodegradable bone implants.

Low Expression of FGF23 and Its Effect on Rats with Intrauterine Growth Retardation

Abstract Objective: To explore the levels of fibroblast growth factor 23 (FGF23) during pregnancy and its relationship with intrauterine growth restriction (IUGR). Methods: Pregnant rats were classified into an ad libitum rat chow group (ad libitum rat chow, AD group, n = 25) and an undernutrition group (50% of their daily food requirement, UN group, n = 25). The levels of maternal serum FGF23, tissue homogenate FGF23, and bone gla protein in fetal rats, and placental FGF23 mRNA and protein expression were examined by enzyme-linked immunosorbent assay, real-time qPCR analysis respectively. Finally, the effect of recombinant FGF23 on the viability of MG-63 cells was determined by cell proliferation assay. Data were analyzed with independent two-tailed t test and one-way analysis of variance. Spearman rank- order correlation coefficients (continuous variables) was performed to determine the relationship of results. Results: The diet restriction induced IUGR in rat offsprings, and the UN group exhibited a significantly lower FGF23 level (P &lt; 0.05, n = 25). The FGF23 level was increased and peaked in maternal serum on gestation day (GD) 15, but peaked in fetal and placenta on GD20. Moreover, the tissue homogenate levels of FGF23 and bone gla protein in fetal rats in both groups were positively correlated (r = 0.923, P &lt; 0.05; r = 0.925, P &lt; 0.05, respectively, n = 25), FGF23 was localized to both decidual and labyrinth zones, with remarkably higher expression on GD20, P &lt; 0.05, n = 25. In vitro, recombinant human FGF23 enhanced MG-63 cell viability, P &lt; 0.05, n = 25. Conclusion: Prenatal undernutrition could decrease the FGF23 expression in fetal rats caused by the mother through the placenta, and induced the IUGR and hindered the ossification. And the FGF23 levels are peaked on GD15 mother but peaked on GD20 placenta and fetuses, these might be associated with the over compensation of maternal placenta on GD20.

Lanthanides-Substituted Hydroxyapatite/Aloe vera Composite Coated Titanium Plate for Bone Tissue Regeneration.

PurposeTo develop the surface-treated metal implant with highly encouraged positive properties, including high anti-corrosiveness, bio-activeness and bio-compatibleness for orthopedic applications.MethodsIn this work, the surface of commercially pure titanium (Ti) metal was treated with bio-compatible polydopamine (PD) by merely immersing the Ti plate in PD solution. The composite of trivalent lanthanide minerals (La3+, Ce3+ and Gd3+)-substituted hydroxyapatite (MHAP) with Aloe vera (AV) gel was prepared and coated on the PD-Ti plate by electrophoretic deposition (EPD) method. The choice of trivalent lanthanide ions is based on their bio-compatible nature and bone-seeking properties. The formation of the PD layer, composites, and composite coatings on Ti plate and PD-Ti surface was confirmed by FT-IR, XRD, SEM and HR-TEM observations. In-vitro assessments such as osteoblasts like MG-63 cell viability, alkaline phosphatase activity and mineralization ability of the MHAP/AV composite were tested, and the composite-coated plate was implanted into a rat bone defect model for in-vivo bone regeneration studies.ResultsThe coating ability of the MHAP/AV composite was highly preferred to PD-treated Ti plate than an untreated Ti plate due to the metal absorption ability of PD. This was confirmed by SEM analysis. The in-vitro and in-vivo studies show the better osteogenic ability of MHAP/AV composite at 14th day and 4th week of an experimental period, respectively.ConclusionThe osteoblast ability of the fabricated device without producing any adverse effect in the rat model recommends that the fabricated device would serve as a better platform on the hard tissue regeneration for load-bearing applications of orthopedics.

Biomedical evaluation of vacuum plasma sprayed tantalum coatings processed by alkali treatment and alkali-heat treatment with different NaOH concentrations

Alkali-heat treatment (AHT) is an effective surface treatment technology for improving the bioactivity of medical metal biomaterials. However, the effects of AHT on the biocompatibility of the original material are not yet fully clear. Accordingly, in the present study, tantalum (Ta) coatings are deposited on Ti6Al4V substrates using a vacuum plasma spraying (VPS) technique and the coatings are then processed using either alkali treatment (AT) or AHT using 0.5 M and 1.0 M NaOH aqueous solution. In vitro bioactivity tests are performed in simulated body fluid for 3~14 days. It is shown that the surface of the AHT sample treated with 0.5 M NaOH (0.5 M AHT) has excellent bioactivity, irrespective of whether or not ultrasonic cleaning (UC) is performed following the heat treatment process. The surface of the AHT sample processed with 1.0 M NaOH (1.0 M AHT) contains a large number of irregular block-shaped compounds, which hinder the bioactivity of the coating. However, following UC treatment, the block-shaped compounds are removed, and the bioactivity of the AHT-UC sample is similar to that of the 0.5 M AHT sample. In in vitro biocompatibility tests for 1–7 days, the Ta coating and 0.5 M AHT-UC coating exhibited significantly better cellular attachment, growth, spreading, and viability of osteoblast-like osteosarcoma MG-63 cells than the 1.0 M AHT-UC coating. It is speculated that this is due to the presence of excess amorphous sodium tantalate on the surface of the 1.0 M AHT-UC coating. Overall, the present results show that AHT treatment performed with an appropriate NaOH concentration yields a significant improvement in both the bioactivity and the biocompatibility of VPS Ta coatings.

Biofabrication and Characterization of Alginate Dialdehyde-Gelatin Microcapsules Incorporating Bioactive Glass for Cell Delivery Application.

The effect of the incorporation of 45S5 bioactive glass (BG) microparticles (mean particle size ≈2µm) on the fabrication and physicochemical properties of alginate dialdehyde-gelatin hydrogel capsules is investigated. The addition of BG particles decreases the hydrogel gelation time by ≈79% and 91% for the samples containing 0.1% w/v and 0.5% w/v BG, respectively. Moreover, it results in increasing average diameter of hydrogel capsules produced via a pressure-driven extrusion technique from about 1000µm for the samples without BG to about 1700 and 1900µm for the samples containing BG at concentrations of 0.1% w/v and 0.5% w/v, respectively. The presence of BG particles in the capsules decreases the degradation rate and improves the bioactivity of the materials. The viability of MG-63 cells encapsulated in all samples increases during the first 7d of cultivation and maintains the same level during 21d of cultivation. The early cell viability in samples containing BG is lower than that in samples without BG. The results show that 45S5 BG can positively regulate the osteogenic activity of cells incorporated in hydrogel capsules. The fabricated composite capsules exhibit promising potential for cell delivery in bone regeneration applications.

Formononetin inhibits osteosarcoma cell proliferation and promotes apoptosis by regulating the miR-214-3p/phosphatase and tensin homolog pathway.

BackgroundPhytoestrogens have a similar molecular structure to estrogens which can produce either estrogenic or anti-estrogenic effects. It is generally believed that phytoestrogens combine with the estrogen receptor of osteosarcoma cells, affecting a variety of signal transduction pathways and cell metabolism, resulting in altered cell proliferation, differentiation, apoptosis, invasion and migration ability. Formononetin (FN) is the active ingredient of traditional Chinese medicine astragalus, angelica, and Pueraria lobate. Our study aims to detect the role of FN on MG-63 cell viability and apoptosis through regulating phosphatase and tensin homolog (PTEN) expression via MicroRNA-214-3p (miR-214-3p).Methods3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Caspase 3 assay evaluated cell viability and apoptosis, respectively. Real-time quantitative polymerase chain reaction (qRT-PCR) and western blot evaluated the mRNA and protein expressions, respectively. The binding site of miR-214-3p/PTEN was detected via dual luciferase assay.ResultsFN suppressed cell viability and induced apoptosis, and decreased miR-214-3p level and promoted PTEN expression. PTEN was then regarded as a target of miR-214-3p, and FN improved PTEN level via inhibiting miR-214-3p. Further analysis showed that overexpressed miR-214-3p improved cell viability and suppressed apoptosis of MG-63 cells by inhibiting PTEN expression.ConclusionsFinally, our results revealed that FN inhibited cell viability and induced apoptosis by regulating miR-214-3p. FN acted as a new treatment for MG-63 cells via increasing PTEN level by inhibiting the miR-214-3p level.

Enterococcus faecalis induces necroptosis in human osteoblastic MG63 cells through the RIPK3 / MLKL signalling pathway.

To explore the activation of necroptosis triggered by Enterococcus faecalis in human osteoblastic MG63 cells and provide new insights into the pathogenesis of refractory apical periodontitis. The viability of MG63 cells exposed to live E.faecalis was investigated using the cell counting kit-8 assay. The relative expressions of specific markers for necroptosis, namely p-RIPK3 and p-MLKL, were determined by western blotting. Cells pretreated with necrosulfonamide and GSK'872, which are specific inhibitors for MLKL and RIPK3, respectively, were then subjected to lactate dehydrogenase (LDH) cytotoxicity assay, flow cytometry analysis and Hoechst 33342/PI double fluorescence staining. Lentiviral-delivered short hairpin RNA (shRNA) targeting MLKL was employed to further confirm the activation of necroptosis in MG63 cells infected with E.faecalis. Transmission electron microscopy was additionally used to observe the morphological characteristics. Statistical analysis was conducted using Student's t-tests or one-way ANOVA followed by the Student-Newman-Keuls test. The infection with E.faecalis significantly inhibited the viability of MG63 cells in a multiplicity of infection- and infection time-dependent manners (P<0.05). In line with this, the expression levels of necroptosis-related markers, p-RIPK3 and p-MLKL, were significantly increased postinfection (P<0.05). Significant reductions in death rate were detected in the case of E.faecalis-infected MG63 cells following pretreatment with the inhibitors of RIPK3 and MLKL (P<0.01). Furthermore, silencing of MLKL by shRNA significantly decreased LDH release (P<0.01) and resulted in less mitochondrial swelling and vacuole-like changes, as well as reduced endoplasmic reticulum expansion. Enterococcus faecalis infection-induced necroptosis of MG63 cells via the RIPK3/MLKL signalling pathway, which may exert a negative influence on the healing process of refractory apical periodontitis. This study may offer novel insights into the pathogenesis and potential therapeutic targets of refractory apical periodontitis.