MG-63 Cells Research Articles

Knockdown of SMYD3 by RNA Interference Regulates the Expression of Autophagy-Related Proteins and Inhibits Bone Formation in Fluoride-Exposed Osteoblasts.

This study aimed to explore the role of histone methyltransferase SET and MYND domain containing 3 (SMYD3) in bone metabolism of osteoblasts exposed to fluoride. The levels of urine fluoride, BALP, and OC and the mRNA expression of SMYD3 were determined in patients with skeletal fluorosis and non-fluoride-exposed people on informed consent. The expression of SMYD3 protein, OC contents, and BALP activities were detected in human osteoblast-like MG63 cells and rat primary osteoblasts treated with sodium fluoride (NaF) for 48 h. The autophagosomes were observed by transmission electron microscopy. Then, we knocked down SMYD3 to confirm whether it was involved in the regulation of bone formation and related to autophagy and Wnt/β-catenin pathway. We observed that OC and BALP levels in patients with skeletal fluorosis significantly increased, while the mRNA expression of SMYD3 significantly decreased in the skeletal fluorosis groups. In vitro, the OC contents, BALP activities, and expression of SMYD3 significantly increased, and many autophagosomes were observed in NaF treated osteoblasts. The downregulation of SMYD3 significantly inhibited OC contents, BALP activities, and expression of autophagy-related proteins, but with no significant changes in the Wnt/β-catenin pathway. Our results demonstrated that fluoride exposure with coal-burning pollution caused orthopedic injuries and abnormalities in the levels of OC and BALP and hindered normal bone metabolism. Silencing the SMYD3 gene could significantly reduce OC and BALP levels via inhibiting the increase in autophagy induced by fluoride.

Structural, mechanical and in vitro studies on pulsed laser deposition of hydroxyapatite on additive manufactured polyamide substrate

Additive manufacturing (AM) is an emerging field that merges engineering and life sciences to produce components that can effectively act as a replacement in the human body. This AM encompasses biofabrication using cells, biological or biomaterials as building blocks to fabricate biological and bio-application oriented substance, device and therapeutic products through a broad range of engineering and biological processes. Furthermore, bioactive coating on BAM surface facilitates biological fixation between the prosthesis and the hard tissue which increases the long term stability and integrity of the implant. In this paper, hydroxyapatite (HA) powder was coated over AM polyamide substrate using pulsed laser deposition. Coating morphology was characterised using scanning electron microscope (SEM) analysis and observed that the coating was dominated by the presence of particle droplet with different sizes. Compounds like tricalcium phosphate and a few amorphous calcium phosphates were found along with HA which was confirmed by X-ray diffraction (XRD) analysis. Fourier transform infrared spectroscopy (FTIR) techniques shows the presence of phosphate and carbonate groups in the HA structure. Nano-indentation and pull-out test reveals that the layer was strong enough and withstands higher load before it peels off. In vitro analysis was evaluated with human osteosarcoma MG-63 cells with respect to the cell viability and results shows that the good viability was observed on coated surface due to combinational effect of Ca2+ and PO4 3− ions. The multitude of characterisation conducted on the coating has established that coating polyamide with HA results in a positive combination for an implant.

Assessment of biodegradability and biocompatibility: An experimental and comparative analysis of magnesium and magnesium-(zinc-tin)/hydroxyapatite composites

This study presents the fabrication and comparative assessment of biodegradation and biocompatibility behaviors of pure Mg, Mg/HA (Hydroxyapatite), Mg-Zn/HA, and Mg-Sn/HA composites with fixed 5 wt% HA and 1 wt% each of Zn and Sn, using novel ultrasonic-assisted rheo casting technology. Characterization techniques, including X-ray diffractometry and scanning electron microscopy integrated with energy dispersive spectroscopy, were employed to analyze phase formation, surface morphology, and elemental composition. Microhardness tests were conducted to assess indentation resistance, while in vitro corrosion performance was evaluated in simulated bodily fluid to compare degradation behavior. Results indicate a uniform distribution of reinforced particles within the matrix with minimal casting defects. Intermetallic phases MgZn and Mg2Sn precipitated along grain boundaries in Mg-Zn/HA and Mg-Sn/HA composites. The Mg-Sn/HA composite exhibited peak microhardness (94.8 HV) due to precipitation strengthening. In contrast, Mg-Zn/HA samples showed a low degradation rate (0.19 mm/yr) and H2 gas evolution rate (0.035 ml/mm2), attributed to uniform distribution of secondary phases and fine grains that mitigate galvanic cell formation and control degradation. Cell viability assay results demonstrated that Mg-Zn/HA composite outperformed all other samples, showing a 94% relative cell growth rate of osteosarcoma MG-63 cells after 2 h of incubation, attributed to strong apatite formation (rich in Ca and P) on the surface post-immersion, promoting cell proliferation.

Extraction and characterization of biocompatible hydroxyapatite (Hap) from red big eye fish bone: Potential for biomedical applications and reducing biowastes

In this study, nanostructured hydroxyapatite (HAp) was successfully extracted from the bones of Priacanthus macracanthus (Red Big Eye), a species commonly processed in the fish industry, generating significant waste. The extraction process utilized an alkaline hydrolysis method optimized with 2 M sodium hydroxide at 250 °C for 5 h, producing high-purity HAp. Fourier transform infrared spectroscopy (FT-IR) confirmed the presence of characteristic phosphate peaks at 1044 cm⁻¹ and 963 cm⁻¹, and hydroxyl peaks at 632 cm⁻¹. Powder X-ray diffraction (XRD) analysis showed prominent peaks at 2θ values of 25.9°, 32.2°, 39.8°, and 46.7°, corresponding to the crystalline planes of HAp. Field-emission scanning electron microscopy (FESEM) revealed spherical HAp particles with sizes ranging from 50 to 80 nm. Biocompatibility was assessed using human osteoblast-like MG-63 cells, showing a proliferation rate of 92 % compared to the control. Cytotoxicity tests indicated no significant adverse effects, supporting the potential use of this HAp in biomedical applications. Importantly, this method offers a sustainable solution for managing fish bone waste, contributing to pollution control by reducing environmental burdens associated with discarded bone wastes. Future research will focus on in vivo biocompatibility studies and exploring applications in pollution mitigation and tissue engineering. This study highlights the dual benefits of utilizing biowaste for valuable HAp production and addressing environmental pollution challenges, making it a promising approach for sustainable material synthesis and environmental management. The cost-effective and environmentally friendly process further underscores the feasibility of scaling up this method for industrial applications, providing a greener alternative to conventional HAp synthesis.

Bromelain-facilitated GNPs: A strategic innate anticancer delivery system for methotrexate into osteosarcoma cells

Osteosarcoma is the most common malignant bone tumor in children and adolescents during rapid bone growth. Traditional chemotherapy has markedly improved patient outcomes but suffers from nonspecific side effects due to nonspecific drug distribution, highlighting the need for targeted therapies. Methotrexate, although effective, poses toxicity concerns and prompts exploration into advanced drug delivery systems like nanoparticles. Here, we developed a novel method of synthesizing gold nanoparticles using bromelain (G-BNPs) as a reducing and capping agent, and we conjugated G-BNPs with methotrexate (G-B-MNPs) via 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide (EDC/NHS) as crosslinker. Our meticulous characterization, which included UV–visible spectroscopy, Transmission electron microscopy (TEM), Dynamic light scattering (DLS), Zeta potential, and Fourier-transform infrared spectroscopy (FTIR) analyses confirmed the successful fabrication and drug conjugation of the G-BNPs. We then evaluated the cytotoxicity of the G-BNPs (sized ∼ 21 nm) and G-B-MNPs (sized ∼ 24 nm) on the osteosarcoma cell lines, Saos-2 and MG-63, as well as the non-cancerous primary osteoblast cells. Our findings revealed that G-B-MNPs significantly increased the cytotoxic impact on osteosarcoma cells compared to methotrexate alone while showing minimal toxicity toward primary osteoblast cells. Importantly, using 4`,6-diamidino-2-phenylindole(DAPI), we demonstrated that G-B-MNPs were delivered directly into the nucleus of the cells without encountering lysosomes. G-B-MNPs can be considered a potential drug delivery method for osteosarcoma treatment by improving effectiveness and reducing adverse effects, thereby enhancing patient prognosis.

Synthesis and characterization of injectable thermosensitive hydrogel based on Pluronic-grafted silk fibroin copolymer containing hydroxyapatite nanoparticles as potential for bone tissue engineering

Injectable hydrogels are promising for bone tissue engineering due to their minimally invasive application and adaptability to irregular defects. This study presents the development of pluronic grafted silk fibroin (PF-127-g-SF), a temperature-sensitive graft copolymer synthesized from SF and modified PF-127 via a carbodiimide coupling reaction. The PF-127-g-SF copolymer exhibited a higher sol-gel transition temperature (34 °C at 16 % w/v) compared to PF-127 (23 °C), making it suitable for injectable applications. It also showed improved flexibility and strength, with a yielding point increase from <10 % to nearly 30 %. Unlike PF-127 gel, which degrades within 72 h in aqueous media, the PF-127-g-SF copolymer maintained a stable gel structure for over two weeks due to its robust crosslinked hydrogel network. Incorporating hydroxyapatite nanoparticles (n-HA) into the hydrogel reduced pore size and decreased swelling and degradation rates, extending structural stability to four weeks. Increasing n-HA concentration from 0 % to 20 % reduced porosity from 80 % to 66 %. Rheological studies indicated that n-HA enhanced the scaffold's strength and mechanical properties without altering gelation temperature. Cellular studies with MG-63 cells showed that n-HA concentration influenced cell viability and mineralization, highlighting the scaffold's potential in bone tissue engineering.

Photodynamic activity of cationic ball-type zinc phthalocyanine in cell culture experiments with MCF-7 and MG63 cancer cells

Effective binding of cationic ball-type zinc phthalocyanine (BT-Pc) to G-quadruplex (G4) DNA molecules has already been demonstrated previously. This motivated us to investigate the PDT performance of BT-Pc in cell culture studies. Accordingly, the present work involves the application of BT-Pc to breast (MCF-7) and osteosarcoma (MG63) cancer cells, and also to healthy fibroblast cells (L929). Cell lines (CL) were irradiated at 640 nm wavelength, and the photodynamic activity was evaluated. The results show that cytotoxicity was significantly stronger in MCF-7 cells than in both L929 and MG63 cells (p &lt; 0.05) in the absence of IPL irradiation. Also, we report that the application of l IPL provided significant photodynamic activity in MCF-7 and MG63 cells (p &lt; 0.05). These results further suggest that BT-Pc might become a promising photosensitizer for future clinical trials.

An In Vitro and In Silico Study of Luteolin-Loaded Zinc Oxide Nanoparticles: Enhancing Bioactivity and Efficacy for Advanced Therapeutic Applications Against Cariogenic Microorganisms.

Introduction Recent studies have explored alternative methods to enhance caries prevention and treatment.Luteolin compound has been noted for its antimicrobial properties, while zinc nanoparticles (Zn NPs) are recognized for their potent antibacterial effects. This study investigates the synthesis, characterization, and antimicrobial efficacy of luteolin-loaded Zn oxide NPs (Luteo-ZnONPs) against cariogenic bacteria. By combining the biofilm-targeting capabilities of luteolin with the antimicrobial properties of Zn NPs, we aim to explore a novel approach for dental caries management. Methods Luteo-ZnONPswere synthesized and characterized using ultraviolet-visible (UV-vis) and Fourier transform infrared (FTIR) spectroscopy, confirming their successful formation and stability. Antimicrobial efficacy was assessed through minimum inhibitory concentration (MIC), demonstrating effectiveness against cariogenic bacteria such asEscherichia coli,Enterococcus faecalis, Pseudomonas aeruginosa, and Streptococcus mutans in different concentrations.The agar well plate method was employed to analyze the growth inhibitory effect of Luteo-ZnONPs (50 and 100µg/ml, respectively). Streptomycin (100µg/ml) was used as apositive control. The results (zone of inhibition (ZOI) in millimeter, mm) were represented as mean± standard deviation.One-way analysis of variance (ANOVA) was employed to detect the significance (p < 0.05) between the groups. Cytotoxicity was analyzed using the3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assayagainst MG63 cells, and doxorubicin was used as a positive control.Wilcoxon rank test was used for the statistical method. Gyrase Bwas downloaded from Protein Data Bank (PDB id: 6F86) and docked against luteolin using Autodock software (version 4.2).The binding score was presented as kcal/mol in table format. Results Characterization results showed that UV-vis spectroscopy revealed characteristic peaks, indicating the successful synthesis and stability of Luteo-ZnONPs. FTIRspectroscopy confirmed the presence of functional groups from luteolin compound interacting with the Zn NPs. It showed effective inhibition againstE. coli on 50µg/ml as 12.45 mm as ZOI and increased with concentration (100 µg/ml as 17.13 mm).It showed minimal ZOI onE. faecalis(8.12, 12.21 on 50 and 100µg/ml, respectively). The cytotoxicity of Luteo-ZnONPs was lesser than doxorubicin on MG63 cells with statistical high significance (p < 0.0014). These results showed thatLuteo-ZnONPs had effective antimicrobial nature againstEnterococcusfamily. Thus, gyrase BfromE. coliwas selected for the molecular docking analysis. The catalytic tunnel in gyrase B (E. coli, PDB: 6F86), influenced by Luteo-ZnONPs, indicated potential for novel, broad-spectrum antimicrobials via selective inhibition at conserved active sites. Conclusion The agar well plate and MIC confirmed that Luteo-ZnONPs exhibited potent antibacterial activity, especiallyat higher concentrations compared to streptomycin.One- way ANOVA demonstrated significant differences in antibacterial efficacy between treatments, validating its superior performance.Its strong interaction onin silicolevel showed the targeted mechanism of action. Luteo-ZnONPs showed lesser toxicity than doxorubicin on MG63 cells. These findings underscore the potential of its broad spectrum antimicrobial nature paving the way for its development into innovative, nontoxic therapeutic solutions.

Blue light photobiomodulation induced osteosarcoma cell death by facilitating ferroptosis and eliciting an incomplete tumor cell stress response

To investigate the potential of blue light photobiomodulation (PBM) in inducing ferroptosis, a novel form of regulated cell death, in OS cells, considering its known effectiveness in various cancer models. In this investigation, we exposed human OS cell lines, HOS and MG63, to different wavelengths (420, 460 and 480 nm) of blue light at varying irradiances, and examined cellular responses such as viability, apoptosis, levels of reactive oxygen species (ROS), and mitochondrial membrane potential (MMP). Transcriptome sequencing was employed to unravel the molecular mechanisms underlying blue light-induced effects, with validation via quantitative real-time PCR (qRT-PCR). Our findings revealed a wavelength- and time-dependent decrease in cell viability, accompanied by increased apoptosis and oxidative stress. Transcriptomic analysis identified differential expression of genes associated with ferroptosis, oxidative stress, and iron metabolism, further validated by qRT-PCR. These results implicated ferroptosis as a significant mechanism in the blue light-induced death of OS cells, potentially mediated by ROS generation and disruption of iron homeostasis. Also, An incomplete stress response was observed in MG63 cells induced by blue light exposure. Hence, blue light PBM holds promise as a therapeutic approach in OS clinical investigations; however, additional exploration of its underlying mechanisms remains imperative.

Mechanical, physical, and biological properties of polycaprolactone/ Mg-doped SrFe12O19 nanocomposite scaffolds for bone tissue engineering applications

Nowadays, the utilization of 3D printing has become common in the construction of composite scaffolds. In this research, the co-precipitation method was applied to synthesize pure strontium hexaferrite oxide (SrFe12O19) and magnesium-doped strontium hexaferrite oxide nanoparticles (Mg–SrFe12O19). The synthesized SrFe12O19 nanoparticles had a spherical morphology with a mean size of 60 nm and magnetization (Ms) value of 54.38 emu/g. The Mg–SrFe12O19 also had a spherical morphology with a mean particle size of 46 nm and a magnetization value of 29.89 emu/g. The produced polycaprolactone composite scaffolds containing different amounts (0, 25, 50, and 75 wt%) of reinforcement were fabricated by the 3D robocasting printing method. Based on the results of the compression test, the 25 wt% addition of the pure SrFe12O19 nanoparticles to the polycaprolactone scaffold increased the compressive strength from 2.87 to 11.68 MPa compared to the 100 wt% pure polycaprolactone scaffold. Furthermore, the polycaprolactone nanocomposite scaffold containing 25 wt% Mg–SrFe12O19 also increased the compressive strength compared to the pure polycaprolactone scaffold to 12.94 MPa. Therefore, the 25 wt% reinforced scaffold was chosen as the optimal sample. The contact angles of the pure polycaprolactone SrFe12O19 and Mg– SrFe12O19 reinforced polycaprolactone scaffolds were 77.17, 68.53, and 35.58°, respectively. The values indicate the significant effect of doping magnesium on the wettability. The degradability of the 3D-printed scaffolds containing 25 wt% of the two different reinforcements was evaluated for 28 days immersing in phosphate-buffered saline (PBS) solution. The results revealed that the degradability was higher for the Mg–SrFe12O19 after 28 days compared to the composite scaffold reinforced by pure SrFe12O19 reinforcement. Moreover, it was shown that the bioactivity and cell adhesion of MG63 cells for the scaffolds reinforced by Mg–SrFe12O19 have increased in laboratory conditions. Based on the MTT test, it was observed that both of the scaffolds were non-toxic. The results obtained in this study, suggest that polycaprolactone nanocomposite scaffolds containing 25 wt% of Mg–SrFe12O19, made by the 3D robocasting printing method, are suitable for bone tissue engineering.

Mussel shell-derived biogenic hydroxyapatite as reinforcement on chitosan-loaded gentamicin composite for antibacterial activity and bone regeneration

In this study, hydroxyapatite (HAp) was synthesized from natural biowaste materials, specifically mussel shells, and combined with chitosan (CS) and gentamicin sulfate antibiotic (GA) using an in-situ method. The resulting composite material, designated HAp/CS-GA, has its physicochemical and structural properties characterized by Fourier transform infrared spectroscopy (FTIR) analysis. The structure was confirmed by X-ray diffraction (XRD) analysis. Additionally, field emission scanning electron microscopy (FE-SEM) equipped with the energy dispersive X-ray spectroscopic (EDX) technique was used to determine the surface topography and main components. The composite of HAp/CS-GA was analyzed using a drug release profile by UV–visible spectroscopy (UV–Vis). The fabricated composites antimicrobial behavior was examined against bone infection-causing Gram-positive and Gram-negative bacteria, showing potential activity against Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus compared to Escherichia coli, respectively. Simultaneously, the cytotoxicity of the composite was evaluated by MTT assay using an MG-63 osteoblast-like cell line that exhibited no toxicity in the prepared composite. After a 24 h incubation period, the MG-63 cells on the HAp/CS-GA composite showed good proliferation, according to Hoechst 33258 fluorescence staining results. The results suggested that the composite had excellent biocompatibility and antibacterial activity and enhanced the osteoblast cell proliferation. Therefore, the designed HAp/CS-GA composite would be a promising candidate for bone tissue engineering.

Physico-Chemical Properties of Copper-Doped Hydroxyapatite Coatings Obtained by Vacuum Deposition Technique.

The hydroxyapatite and copper-doped hydroxyapatite coatings (Ca10-xCux(PO4)6(OH)2; xCu = 0, 0.03; HAp and 3CuHAp) were obtained by the vacuum deposition technique. Then, both coatings were analyzed by the X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and water contact angle techniques. Information regarding the in vitro antibacterial activity and biological evaluation were obtained. The XRD studies confirmed that the obtained thin films consist of a single phase associated with hydroxyapatite (HAp). The obtained 2D and 3D SEM images did not show cracks or other types of surface defects. The FTIR studies' results proved the presence of vibrational bands characteristic of the hydroxyapatite structure in the studied coating. Moreover, information regarding the HAp and 3CuHAp surface wettability was obtained by water contact angle measurements. The biocompatibility of the HAp and 3CuHAp coatings was evaluated using the HeLa and MG63 cell lines. The cytotoxicity evaluation of the coatings was performed by assessing the cell viability through the MTT assay after incubation with the HAp and 3CuHAp coatings for 24, 48, and 72 h. The results proved that the 3CuHAp coatings exhibited good biocompatible activity for all the tested intervals. The ability of Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa) cells to adhere to and develop on the surface of the HAp and 3CuHAp coatings was investigated using AFM studies. The AFM studies revealed that the 3CuHAp coatings inhibited the formation of P. aeruginosa biofilms. The AFM data indicated that P. aeruginosa's attachment and development on the 3CuHAp coatings were significantly inhibited within the first 24 h. Both the 2D and 3D topographies showed a rapid decrease in attached bacterial cells over time, with a significant reduction observed after 72 h of exposure. Our studies suggest that 3CuHAp coatings could be suitable candidates for biomedical uses such as the development of new antimicrobial agents.

In Situ Hydrogel with Immobilized Mn-Porphyrin for Reactive Oxygen Species Scavenging, Oxygen Generation, and Risedronate Delivery in Bone Defect Treatment.

We propose a hydrogel immobilized with manganese porphyrin (MnP), a biomimetic superoxide dismutase (SOD), and catalase (CAT) to modulate reactive oxygen species (ROS) and hypoxia that impede the repair of large bone defects. Our hydrogel synthesis involved thiolated chitosan and polyethylene glycol-maleimide conjugated with MnPs (MnP-PEG-MAL), which enabled in situ gelation via a click reaction. Through optimization, a hydrogel with mechanical properties and catalytic effects favorable for bone repair was selected. Additionally, the hydrogel was incorporated with risedronate to induce synergistic effects of ROS scavenging, O2 generation, and sustained drug release. In vitro studies demonstrated enhanced proliferation and differentiation of MG-63 cells and suppressed proliferation and differentiation of RAW 264.7 cells in ROS-rich environments. In vivo evaluation of a calvarial bone defect model revealed that this multifunctional hydrogel facilitated significant bone regeneration. Therefore, the hydrogel proposed in this study is a promising strategy for addressing complex wound environments and promoting effective bone healing.

Benzimidazole-oxindole hybrids: A novel class of selective dual CDK2 and GSK-3β inhibitors of potent anticancer activity.

A new series of benzimidazole-oxindole hybrids 8a-x was discovered as dual cyclin-dependent kinase (CDK2) and glycogen synthase kinase-3-beta (GSK-3β) inhibitors with potent anticancer activity. The synthesized hits displayed potent anticancer activity against national cancer institute cancer cell lines in single-dose and five-dose assays. Moreover, the derivatives 8k, 8l, 8n, 8o, and 8p demonstrated potent cytotoxic activity against PANC-1 cells with IC50 = 1.88-2.79 µM. In addition, the hybrids 8l, 8n, 8o, and 8p displayed potent antiproliferative activity on the MG-63 cell line (IC50 = 0.99-1.90 µM). Concurrently, the benzimidazole-oxindole hybrid 8v exhibited potent dual CDK2/GSK-3β inhibitory activity with IC50 values of 0.04 and 0.021 µM, respectively. In addition, 8v displayed more than 10-fold higher selectivity toward CDK2 and GSK-3 β over CDK1, CDK5, GSK-3α, vascular endothelial growth factor receptor-2, and B-rapidly accelerated fibrosarcoma. Screening of the effect of 8n and 8v on the cell cycle and apoptosis of PANC-1 and MG-63 cells displayed their ability to arrest their cell cycle at the G2-M phase and to potentiate the apoptosis of both cell lines. In silico docking of the benzimidazole-oxindole hybrid 8v into the catalytic pocket of both CDK2 and GSK-3β revealed its perfect fitting through the formation of hydrogen bonding and hydrophobic interactions with the key amino acids in the binding sites. In addition, in silico absorption, distribution, metabolism, excretion studies proved that 8a-x exhibit satisfactory drug-likeness properties for drug development.

Advancing Bioactive Material for Mandibular Bone Regeneration: Transformation of Fibrous Mat into 3D Matrix Cotton for Enhanced Shape Retention and Rapid Hemostasis.

Transformation of a fibrous mat into a three-dimensional (3D) scaffold opens up abundant innovative prospects in biomedical research, particularly for studying both soft as well as hard tissues. Electrospun nanofibers, which mimic the extracellular matrix have attracted significant attention in various studies. This research focuses on rapidly converting a fibrous mat made of polycaprolactone (PCL)/pluronic F-127 (PF-127) with different percentages of monetite calcium phosphate (MCP) into desirable 3D matrix cotton using a unique gas foaming technology. These matrix cottons possess biomimetic properties and have oriented porous structures. Using this innovative technique, various shapes of 3D matrix cotton, such as squares, hollow tubes, and other customizable forms, were successfully produced. Importantly, these 3D matrix cottons showed a consistent distribution of monetite particles with total porosity ranging from 90% to 98%. The structure of the 3D matrix cotton, its water/blood absorption capacity, the potential for causing non-hemolysis, and rapid hemostatic properties were thoroughly investigated. Additionally, periodontal cells were cultured on the 3D matrix cotton to assess their viability and morphology, revealing promising results. Furthermore, a coculture study involving NIH-3T3 and MG-63 cells on the 3D matrix cotton showed spheroidal formation within 24 h. Notably, in vitro assessments indicated that the matrix cotton containing 15% monetite (PCL-MMC15%) exhibited superior absorbent capabilities, excellent cell viability, and rapid hemostatic characteristics. Subsequently, the effectiveness of PCL-MMC15% in promoting mandibular bone regeneration was evaluated through an in vivo study on rabbits using a mandibular injury model. The results demonstrated that PCL-MMC15% facilitated the resolution of defects in the mandibular region by initiating new bone formation. Therefore, the presented 3D matrix cotton (PCL-MMC15%) shows significant promise for applications in both mandibular bone regeneration and hemostasis.

Silk Fibroin-Enriched Bioink Promotes Cell Proliferation in 3D-Bioprinted Constructs.

Three-dimensional (3D) bioprinting technology enables the controlled deposition of cells and biomaterials (i.e., bioink) to easily create complex 3D biological microenvironments. Silk fibroin (SF) has recently emerged as a compelling bioink component due to its advantageous mechanical and biological properties. This study reports on the development and optimization of a novel bioink for extrusion-based 3D bioprinting and compares different bioink formulations based on mixtures of alginate methacrylate (ALMA), gelatin and SF. The rheological parameters of the bioink were investigated to predict printability and stability, and the optimal concentration of SF was selected. The bioink containing a low amount of SF (0.002% w/V) was found to be the best formulation. Light-assisted gelation of ALMA was exploited to obtain the final hydrogel matrix. Rheological analyses showed that SF-enriched hydrogels exhibited greater elasticity than SF-free hydrogels and were more tolerant to temperature fluctuations. Finally, MG-63 cells were successfully bioprinted and their viability and proliferation over time were analyzed. The SF-enriched bioink represents an excellent biomaterial in terms of printability and allows high cell proliferation over a period of up to 3 weeks. These data confirm the possibility of using the selected formulation for the successful bioprinting of cells into extracellular matrix-like microenvironments.

Sirtuin 3-activated superoxide dismutase 2 mediates fluoride-induced osteoblastic differentiation in vitro and in vivo by down-regulating reactive oxygen species.

Skeletal fluorosis is a chronic metabolic bone disease caused by long-term excessive fluoride intake. Abnormal differentiation of osteoblasts plays an important role in disease progression. Research on the mechanism of fluoride-mediated bone differentiation is necessary for the prevention and treatment of skeletal fluorosis. In the present study, a rat model of fluorosis was established by exposing it to drinking water containing 50mg/L F-. We found that fluoride promoted Runt-related transcription factor 2 (RUNX2) as well as superoxide dismutase 2 (SOD2) and sirtuin 3 (SIRT3) expression in osteoblasts of rat bone tissue. In vitro, we also found that 4mg/L sodium fluoride promoted osteogenesis-related indicators as well as SOD2 and SIRT3 expression in MG-63 and Saos-2 cells. In addition, we unexpectedly discovered that fluoride suppressed the levels of reactive oxygen species (ROS) and mitochondrial reactive oxygen species (mtROS) in osteoblasts. When SOD2 or SIRT3 was inhibited in MG-63 cells, fluoride-decreased ROS and mtROS were alleviated, which in turn inhibited fluoride-promoted osteogenic differentiation. In conclusion, our results suggest that SIRT3/SOD2 mediates fluoride-promoted osteoblastic differentiation by down-regulating reactive oxygen species.

Apoptotic Induction by Biosynthesized Gold Nanoparticles Using Phormidesmis communis Strain AB_11_10 against Osteosarcoma Cancer.

Phormidesmis communis strain AB_11_10 was isolated and identified using microscopy and 16s rRNA sequencing, and its phytochemical constituents were determined using liquid chromatography-quadrupole time-of-flight mass spectrometry. The isolate had a segmented filamentous shape with a blue-green color. Many biomolecules, including organic compounds, amino acids, and fatty acids, were detected. P. communis strain AB_11_10 was used to synthesize gold nanoparticles (Ph-AuNPs) by adjusting the optimum reaction conditions. The concentration, algal/precursor ratio, temperature, reaction time, and pH significantly influenced the synthesis of the Ph-AuNPs. Mixing 1 mL of 0.5 mM of HAuCl4 with 1 mL of algal extract and exposing the mixture to 100 °C for 30 min at pH 5.6 were the optimum conditions for the biosynthesis of Ph-AuNPs at a wavelength of 524.5 nm. The Ph-AuNPs were characterized using TEM, SEM, EDX, and mapping Zeta sizer and FTIR. The Ph-AuNPs had quasi-spherical to triangular shapes with an average diameter of 9.6 ± 4.3 nm. Ph-AuNPs composed of 76.10 ± 3.14% of Au and trace amounts of carbon and oxygen were detected, indicating that the P. communis strain AB_11_10 successfully synthesized Ph-AuNPs. The hydrodynamic diameter of the Ph-AuNPs was 28.5 nm, and their potential charge was -17.7 mV. O-H, N-H, C=C, N-O, C-H, and C-O were coated onto the surfaces of the Ph-AuNPs. These groups correspond to algal phytochemicals, which may have been the main reducing and stabilizing substances during the Ph-AuNP synthesis. The therapeutic activity of the Ph-AuNPs against osteosarcoma cancers was examined in MG-63 and SAOS-2 cell lines, while their biocompatibility was tested against Vero cell lines using a sulforhodamine B assay. The Ph-AuNPs had potent antitumor activity against the MG-63 and SAOS-2 cells, with a low toxicity toward Vero cells. Flow cytometry and cell cycle arrest analyses revealed that the Ph-AuNPs enhanced the apoptotic pathway and arrested the cell cycle in the MG-63 and SAOS-2 cells. P. communis strain AB_11_10 provides a new source to synthesize small, stable, and biocompatible AuNPs that act as apoptotic enhancers in osteosarcoma.

Enhanced strength, cytocompatibility, and corrosion resistance of biodegradable Zn-1.5Mg-0.5HA-xMn (x=1 and 1.5 wt%) composites for bone implant applications

Zn, a biodegradable metal, exhibits immense capability as a bioresorbable implant material because of its remarkable biocompatibility and stronger corrosion resistance than Mg. Nonetheless, Zn's limited mechanical strength and hardness have significantly hindered its widespread implementation. This study aimed to strengthen the mechanical, degradation resistance, and biocompatibility of zinc composites by rolling them and investigating the impact of Mn content on the material properties of Zn composites. The prepared hot rolled Zn-1.5Mg-0.5HA(hydroxyapatite)-1.5Mn (ZMR2) sample shows enhanced Ultimate tensile strength (UTS 209 MPa) and hardness (103 HV). In a PBS solution, the degradation rates of the hot-rolled sample show a consistent reduction as the content of Mn increases, reaching a rate of 0.032 mm/year. Furthermore, excellent hemocompatibility was observed for both the cast and rolled specimens. However, the rolled ZMR2 sample exhibited the lowest value (4.5 %) among the two. The cultured MG63 cells demonstrated high viability when exposed to diluted extracts (25 % and 50 % extract) of the HR ZMR2 sample from Day 1 to Day 5. In both cases, the viability exceeded 80 %, indicating the absence of any potential cytotoxic effects.

Evaluating the osteogenic properties of polyhydroxybutyrate-zein/multiwalled carbon nanotubes (MWCNTs) electrospun composite scaffold for bone tissue engineering applications

In this investigation, the electrospun nanocomposite scaffolds were developed utilizing poly-3-hydroxybutyrate (PHB), zein, and multiwalled carbon nanotubes (MWCNTs) at varying concentrations of MWCNTs including 0.5 and 1 wt%. Based on the SEM evaluations, the scaffold containing 1 wt% MWCNTs (PZ-1C) exhibited the lowest fiber diameter (384 ± 99 nm) alongside a suitable porosity percentage. The presence of zein and MWCNT in the chemical structure of the scaffold was evaluated by FTIR. Furthermore, TEM images revealed the alignment of MWCNTs with the fibers. Adding 1 % MWCNTs to the PHB-zein scaffold significantly enhanced tensile strength by about 69 % and reduced elongation by about 31 %. Hydrophilicity, surface roughness, crystallinity, and biomineralization were increased by incorporating 1 wt% MWCNTs, while weight loss after in vitro degradation was decreased. The MG-63 cells exhibited enhanced attachment, viability, ALP secretion, calcium deposition, and gene expression (COLI, RUNX2, and OCN) when cultivated on the scaffold containing MWCNTs compared to the scaffolds lacking MWCNTs. Moreover, the study found that MWCNTs significantly reduced platelet adhesion and hemolysis rates below 4 %, indicating their favorable anti-hemolysis properties. Regarding the aforementioned results, the PZ-1C electrospun composite scaffold is a promising scaffold with osteogenic properties for bone tissue engineering applications.