Human Osteoblastic Cells Research Articles

Potential effect of Yemeni Sidr Honey on the Viability of Gingival Fibroblasts and Osteoblast Cells

Background/aim: The aim of this research is to investigate the potential beneficial effects of Yemen Sidr honey on human gingival fibroblast and osteoblast cell viability and proliferation. Materials and methods: MTT assays were conducted, and the cells were analyzed using an ELISA reader at 590nm. Cell viability was determined based on the optical density readings. Results: At a lower concentration 5μL, the fibroblast and osteoblast cells exhibited a cell viability percentage of over 50%. Conclusion: Yemen Sidr honey is biocompatible and non-toxic to the cultured fibroblast and osteoblast cells.

Novel Antimicrobial Agents Based on Zinc-Doped Hydroxyapatite Loaded with Tetracycline.

In this paper, we present for the first time the development of zinc-doped hydroxyapatite enriched with tetracycline (ZnHApTe) powders and provide a comprehensive evaluation of their physico-chemical and biological properties. Various techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used for the sample's complex evaluation. Moreover, the biocompatibility of zinc-doped hydroxyapatite (ZnHAp) and ZnHApTe nanoparticles was evaluated with the aid of human fetal osteoblastic cells (hFOB 1.19 cell line). The results of the biological assays suggested that these nanoparticles hold great promise as potential candidates for the future development of novel biocompatible and antimicrobial agents for biomedical applications. The antimicrobial properties of the ZnHAp and ZnHApTe nanoparticles were assessed using the standard reference microbial strains Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231. The results of the in vitro antimicrobial assay demonstrated that both tested materials exhibited good antimicrobial activity. Additionally, these data also indicated that the antimicrobial effects of the ZnHAp nanoparticles were intensified by the presence of tetracycline (Te). Furthermore, the results also suggested that the antimicrobial activity of the samples increased with the incubation time.

The comparison of extracellular vesicles with matrix vesicles derived from human vascular smooth muscle versus bone osteoblastic and osteosarcoma cells

The comparison of extracellular vesicles with matrix vesicles derived from human vascular smooth muscle versus bone osteoblastic and osteosarcoma cells

Tailoring zirconia surface topography via femtosecond laser-induced nanoscale features: effects on osteoblast cells and antibacterial properties

The performance and long-term durability of dental implants hinge on the quality of bone integration and their resistance to bacteria. This research aims to introduce a surface modification strategy for zirconia implants utilizing femtosecond laser ablation techniques, exploring their impact on osteoblast cell behavior and bacterial performance, as well as the integral factors influencing the soft tissue quality surrounding dental implants. Ultrafast lasers were employed to craft nanoscale groove geometries on zirconia surfaces, with thorough analyses conducted using x-ray diffraction, scanning electron microscopy, atomic force microscopy, and water contact angle measurements. The study evaluated the response of human fetal osteoblastic cell lines to textured zirconia ceramics by assessing alkaline phosphatase activity, collagen I, and interleukin 1βsecretion over a 7 day period. Additionally, the antibacterial behavior of the textured surfaces was investigated usingFusobacterium nucleatum, a common culprit in infections associated with dental implants. Ciprofloxacin (CIP), a widely used antibacterial antibiotic, was loaded onto zirconia ceramic surfaces. The results of this study unveiled a substantial reduction in bacterial adhesion on textured zirconia surfaces. The fine biocompatibility of these surfaces was confirmed through the MTT assay and observations of cell morphology. Moreover, the human fetal osteoblastic cell line exhibited extensive spreading and secreted elevated levels of collagen I and interleukin 1βin the modified samples. Drug release evaluations demonstrated sustained CIP release through a diffusion mechanism, showcasing excellent antibacterial activity against pathogenic bacteria, includingStreptococcus mutans, Pseudomonas aeruginosa, andEscherichia coli.

Managing Oxidative Stress Using Vitamin C to Improve Biocompatibility of Polycaprolactone for Bone Regeneration In Vitro.

Increased oxidative stress in bone cells is known to negatively alter favorable bone regeneration. This study aimed to develop a porous polycaprolactone (PCL) membrane incorporated with 25 wt % Vitamin C (PCL-Vit C) and compared it to the PCL membrane to control oxidative stress and enhance biomineralization in vitro. Both membranes were characterized using SEM-EDS, FTIR spectroscopy, and surface hydrophilicity. Vitamin C release was quantified colorimetrically. Assessments of the viability and attachment of human fetal osteoblast (hFOB 1.19) cells were carried out using XTT assay, SEM, and confocal microscopy, respectively. ROS generation and wound healing percentage were measured using flow cytometry and ImageJ software, respectively. Mineralization study using Alizarin Red in the presence or absence of osteogenic media was carried out to measure the calcium content. Alkaline phosphatase assay and gene expression of osteogenic markers (alkaline phosphatase (ALP), collagen Type I (Col1), runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), and osteopontin (OPN)) were analyzed by real-time PCR. SEM images revealed smooth, fine, bead-free fibers in both membranes. The FTIR spectrum of pure vitamin C was replaced with peaks at 3436.05 and 2322.83 cm-1 in the PCL-Vit C membrane. Vitamin C release was detected at 15 min and 1 h. The PCL-Vit C membrane was hydrophilic, generated lower ROS, and showed significantly higher viability than the PCL membrane. Although both PCL and PCL-Vit C membranes showed similar cellular and cytoskeletal morphology, more cell clusters were evident in the PCL-Vit C membrane. Lower ROS level in the PCL-Vit C membrane displayed improved cell functionality as evidenced by enhanced cellular differentiation with more intense alizarin staining and higher calcium content, supported by upregulation of osteogenic markers ALP, Col1, and OPN even in the absence of osteogenic supplements. The presence of Vitamin C in the PCL-Vit C membrane may have mitigated oxidative stress in hFOB 1.19 cells, resulting in enhanced biomineralization facilitating bone regeneration.

Effect of luteolin on oxidative stress and inflammation in the human osteoblast cell line hFOB1.19 in an inflammatory microenvironment

BackgroundPeriapical lesions are characterized by periapical inflammation and damage to periapical tissues and eventually lead to bone resorption and even tooth loss. H2O2 is widely used in root canal therapy for patients with periapical inflammation. Luteolin possesses high anti-inflammatory, antioxidant, and anticancer potential. However, the underlying mechanism of the efficacy of H2O2 and luteolin on oxidative stress and inflammatory tissue has not been previously addressed. We aimed to investigate the anti-inflammatory and antioxidative effects of luteolin on H2O2-induced cellular oxidative inflammation.MethodsAfter human osteoblasts (hFOB1.19) were treated with lipopolysaccharide (LPS), luteolin, or H2O2, cell proliferation was analysed by using a cell counting kit-8 (CCK-8), cell apoptosis was measured by using flow cytometry, the production of reactive oxygen species (ROS) was evaluated by using an oxidation-sensitive probe DCFH-DA ROS assay kit, and the expression of genes and proteins was detected by using reverse transcription quantitative polymerase chain reaction (RT‒qPCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA).ResultsWe demonstrated that inflammation is closely related to oxidative stress and that the oxidative stress level in the inflammatory environment is increased. Luteolin inhibited the H2O2-induced increase in the expression of interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor α (TNF-α) and significantly repressed the H2O2-induced increase in ROS, as well as markedly strengthened superoxide dismutase (SOD) activity in hFOB1.19 cells. Moreover, we detected that luteolin may inhibit H2O2-induced hFOB1.19 cell injury by suppressing the NF-κB pathway.ConclusionWe elucidated that luteolin protected human osteoblasts (hFOB1.19) from H2O2-induced cell injury and inhibited the production of proinflammatory cytokines by suppressing the NF-κB signalling pathway. Our findings provide a potential drug for treating H2O2-induced periodontitis and cell injury.

Physico-Chemical and Biological Features of Fluorine-Substituted Hydroxyapatite Suspensions.

Infections related to orthopedic/stomatology surgery are widely recognized as a significant health concern. Therefore, the development of new materials with superior biological properties and good stability could represent a valuable alternative to the classical treatments. In this paper, the fluorine-substituted hydroxyapatite (FHAp) suspension, with the chemical formula Ca10(PO4)6(OH)2-2xF2x (where x = 0.05), was prepared using a modified coprecipitation technique. Stability studies were conducted by zeta potential and ultrasound measurements for the first time. The X-ray diffraction (XRD) patterns of FHAp powders displayed a hexagonal structure akin to that of pure hydroxyapatite (HAp). The XPS general spectrum revealed peaks corresponding to the constituent elements of fluorine-substituted hydroxyapatite such as calcium, phosphorus, oxygen, and fluorine. The purity of the obtained FHAp samples was confirmed by energy-dispersive X-ray spectroscopy (EDS) studies. The FHAp morphology was evaluated by scanning electron microscopy (SEM) measurements. Fourier-transform infrared spectroscopy (FTIR) studies were performed in order to study the vibrational properties of the FHAp samples. The FHAp suspensions were tested for antibacterial activity against reference strains such as Staphylococcus aureus 25923 ATCC, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231. Additionally, the biocompatibility of the FHAp suspensions was assessed using human fetal osteoblastic cells (hFOB 1.19 cell line). The results of our biological tests suggest that FHAp suspensions are promising candidates for the future development of new biocompatible and antimicrobial agents for use in the biomedical field.

P-628 The role of Anti-Müllerian Hormone (AMH) on human osteoblast differentiation

Abstract Study question May AMH, an ovarian hormone belonging to the Transforming Growth Factor β superfamily (TGF-β), represent a possible candidate for use as a bone anabolic factor? Summary answer Our findings provided interesting clues on the stimulatory effects of AMH on mature osteoblasts expressing its specific receptor, the Anti-Müllerian Hormone Type-2 receptor (AMHRII). What is known already Impaired bone formation is a principal pathogenetic mechanism mediating bone fragility in osteoporosis. Several growth factors capable of inducing bone matrix apposition by increasing the number of osteoblast precursor cells or promoting the function of mature osteoblasts have been identified, including members of the TGF-β superfamily such as BMPs. However, their clinical use is limited due to their pleiotropic extraskeletal effects. Anti-Müllerian Hormone (AMH) is a member of the TGF-β superfamily whose role in bone tissues has never been investigated. To date, AMH functions and the expression of its specific receptor are mainly limited to the reproductive organs. Study design, size, duration We performed in vitro studies on Human Osteoblasts (HOb) to evaluate the expression and the functionality of AMH receptor type-2 and investigate the effects of recombinant AMH (rhAMH) exposure on osteogenic gene expression and osteoblast functions. Participants/materials, setting, methods RT-PCR, real-time PCR and Western blotting analyses were performed in Hob cells cultured both in the presence and in the absence of 100 ng/mL rhAMH to evaluate the effect of AMH exposure on osteoblast differentiation. Alizarin red staining was performed after 14 days of treatment with 100 ng/mL rhAMH to assess the mineralized nodule formation. Main results and the role of chance Our study revealed the presence of a strong mRNA and protein expression of AMHRII in HOb cells, thus indicating that osteoblasts may represent a specific target for exogenous AMH treatment. We also observed that rhAMH exposure increased SMAD 1/5 protein levels, demonstrating that the binding of AMHRII by AMH was able to activate the SMAD-mediated AMH signalling pathway. Interestingly, we also observed that AMH treatment upregulates mRNA levels of crucial osteoblastic transcription factors such as RUNX2 and OSX and extracellular matrix proteins including OPN and OC. Consistently, the prolonged exposure to AMH also promoted matrix mineralization in HOb cells, as demonstrated by both increased ALP gene expression and the greater amount of mineralized nodules observed in AMH-treated osteoblasts compared to untreated controls. Limitations, reasons for caution The study was conducted only in HOb cells. Additional functional studies are needed to investigate the action mechanism of AMH in the other bone cells to understand the mechanisms by which AMH may influence bone homeostasis and pave the way for subsequent in vivo studies. Wider implications of the findings This study may have translation value in opening the perspective that AMH may be an effective candidate to counteract bone loss in osteoporotic patients by developing a new therapy selectively targeting osteoblast with minimal off-target effect. Trial registration number Not Applicable

Downregulation of B4GALNT1 inhibits proliferation and metastasis of osteosarcoma cells.

Osteosarcoma is the most common malignant bone tumor in children and adolescents, characterized by a high potential for proliferation and metastasis. Patients with osteosarcoma who have distant metastases generally have a poor prognosis. Challenges in treatment include incomplete resection of tumor and chemotherapy resistance, with no effective cure currently available. Recent studies suggest that β-1,4-N-acetyl-galactosaminyltransferase 1 (B4GALNT1) plays a role in the progression of various malignant tumors. However, the function of B4GALNT1 in osteosarcoma cells has not been reported. This study aims to investigate the expression of B4GALNT1 in osteosarcoma tissues compared to normal tissues and to explore its effects on the proliferation, migration, and invasion of osteosarcoma cells, thereby providing new theoretical foundations and directions for the treatment of osteosarcoma patients. Tumor tissues and corresponding normal tissue samples were collected from 16 osteosarcoma patients who underwent tumor resection at the Second Xiangya Hospital of Central South University. The patients' ages ranged from 8 to 17 years (median age 12 years). The expression of B4GALNT1 mRNA in osteosarcoma tissues, corresponding normal tissues, 3 osteosarcoma cell lines (MG63, Saos-2, and U2OS), and human fetal osteoblastic cells (hFOB) was detected using real-time reverse transcription PCR (real-time RT-PCR). The effects of B4GALNT1 knockdown on the proliferation of osteosarcoma cells Saos-2 and U2OS were analyzed using cell counting kit-8 (CCK-8) assays and colony formation assays. The effects of B4GALNT1 knockdown on the migration and invasion abilities of Saos-2 and U2OS cells were evaluated using Transwell migration and invasion assays. Western blotting analysis was performed to assess the impact of B4GALNT1 knockdown on the expression of epithelial-mesenchymal transition (EMT) and invasion-related proteins in Saos-2 and U2OS cells. Real-time RT-PCR results showed that B4GALNT1 mRNA expression levels were significantly higher in osteosarcoma tissues and the 3 osteosarcoma cell lines compared to normal tissues and hFOB cells (all P<0.01). CCK-8 and colony formation assays indicated that B4GALNT1 knockdown significantly reduced the proliferation rate of osteosarcoma cells compared to the control group (all P<0.05). Transwell migration and invasion assays demonstrated that B4GALNT1 knockdown significantly decreased the number of migrating and invading osteosarcoma cells (all P<0.01). Western blotting analysis revealed that B4GALNT1 knockdown inhibited the expression of N-cadherin, Snail, Vimentin, and matrix metalloproteinase 9 (MMP9) compared to the control group (all P<0.01). B4GALNT1 is upregulated in osteosarcoma tissues and cell lines, and its knockdown suppresses the malignant phenotype of osteosarcoma cells. B4GALNT1 may function as an oncogene in the proliferation and metastasis of osteosarcoma cells.

Biocompatibility Evaluation of Ampicillin-Loaded Whitlockite for Bone Regeneration.

Introduction Whitlockite (WH), a rare phosphate mineral within the apatite group, shows potential for bone regeneration owing to its superior composition and biocompatibility compared to hydroxyapatite. It can serve as a carrier for bioactive molecules, gradually releasing them to stimulate bone growth and expedite healing. This study aims to assess the biocompatibility of antibiotic-loaded WH, focusing on ampicillin, for bone regeneration applications. Methodology WH particles loaded with varying concentrations of ampicillin (10 and 25 mM) underwent biocompatibility assessments using the MTT assay. One gram of particles was incubated in 10 mL of culture medium for 24 and 48 hours. Experimental groups included control, WH, WH with ampicillin at 10 mM (WH+A10), WH with ampicillin at 25 mM (WH+A25), and positive control treated with 0.1% Triton X detergent. Subsequently, after a three-day culture period, RunX2 gene expression, indicative of osteoblastic differentiation, was quantified using real-time PCR analysis. Results Our research evaluated the bioactivity of WH particles treated with human osteoblastic cells using the MTT assay. While 10 mM ampicillin-loaded WH showed no significant difference in metabolic activity at both 24 and 48 hours, 25 mM ampicillin-loaded WH exhibited a slight reduction in metabolic activity at 24 hours, which normalized by 48 hours. Additionally, we assessed osteogenic potential and showed a significant increase in RunX2 expression with ampicillin-loaded WH, indicating sustained osteogenic properties. Conclusions Our study underscores the promising biocompatibility of WH particles by retaining their osteogenic properties even when, loaded with ampicillin, offering a potential avenue for future bone regeneration strategies.

Evaluation of Cardiospermum halicacabum on Bone Morphogenetic Protein-2 (BMP2) mRNA Expression in Osteoblast Cells.

Introduction Maintaining bone health is crucial for overall well-being, with osteoblasts playing a vital role in bone formation. Bone morphogenetic protein-2 (BMP2) is a key regulator, stimulating bone matrix synthesis and osteoblast differentiation. Recognizing BMP2's significance, there's growing interest in natural compounds, such as Cardiospermum halicacabum. This study explores Cardiospermum halicacabum's potential influence on BMP2 mRNA expression in osteoblast cells for insights into bone health modulation. Materials and methods This research utilized Cardiospermum halicacabum to explore its impact on MG-63 cells, a human osteoblast cell line. Osteoblast cells were cultured in Dulbecco's modified Eagle's medium (DMEM), supplemented with 10% heat-inactivated fetal bovine serum, and maintained at 37°C in a 5% CO2 and 95% air environment. Cell viability was evaluated by seeding osteoblast cells into 96-well plates and exposing them to different concentrations of Cardiospermum halicacabum (2.0 μg/ml and 20 μg/ml). The study observed both the promotion of osteoblast cell growth in MG-63 and morphological changes in thecells under an inverted light microscope at 10x magnification. Results were presented using one-way analysis of variance (ANOVA) conducted with IBM SPSS Statistics for Windows, Version 23 (Released 2015; IBM Corp., Armonk, New York, United States). Result The reverse transcription-polymerase chain (RT-PCR) results revealed an increased expression of BMP-2 mRNA fold change in comparison to the control group. A clear positive correlation was observed between the BMP-2 mRNA fold change and the notable increase in the concentration of Cardiospermum halicacabum. This investigation revealed a direct association of BMP-2 mRNA expressionwith the proliferation of osteoblast cells. Specifically, the BMP-2 mRNA fold change was recorded at 2.26±1.05 in Cardiospermum halicacabum at 2.0 μg/ml and 2.0 ± 0.84 at 20 μg/ml, with corresponding significances of 0.00, respectively. Conclusion Potential effects of Cardiospermum halicacabum on BMP-2 mRNA expression in osteoblast cellsand its role in bone health modulation revealed that Cardiospermum halicacabum may upregulate BMP-2 mRNA expression, suggesting its potential as a natural compound for enhancing bone formation. The observed positive correlation between Cardiospermum halicacabum concentration and BMP-2 mRNA fold change showed the significance of this botanical agent in promoting osteoblast cell proliferation. These results highlight the importance of further research to explore the applications of Cardiospermum halicacabum in managing bone disorders and improving overall bone health.

A GAD1 inhibitor suppresses osteosarcoma growth through the Wnt/β-catenin signaling pathway

BackgroundAs a marker of the GABAergic system, the expression of glutamate decarboxylase 1 (GAD1) is mainly restricted to the central nervous system. Emerging studies have shown that aberrant expression of GAD1 in tumor tissues may promote tumor cell growth. The role of GAD1 in the development of osteosarcoma (OS) remains unclear, so this study sought to investigate the expression status of GAD1 and the effect of its specific inhibitor 3-mercaptopropionic acid (3-MPA) on OS. MethodsThe R2 database was used to analyze the relationship between the expression of GAD1 and clinical prognosis in OS patients. Immunohistochemistry was used to compare the expression profile of GAD1 between OS and matched neighboring tissues. The potential antitumor effects of 3-MPA on cell viability, colony formation and the cell cycle were examined. Moreover, the in vivo effect of 3-MPA on tumor growth was investigated using tumor-bearing nude mice. ResultsThe expression level of GAD1 was aberrantly upregulated in OS tissues, but almost no expression of GAD1 was found in matched neighboring tissues. Western blotting analyses showed upregulation of GAD1 in OS cells compared to human osteoblast cells. In vitro and in vivo, 3-MPA significantly suppressed the growth of OS. Regarding the mechanism, 3-MPA inhibited β-catenin and cyclin D1 in OS cells, thereby inactivating the Wnt/β-catenin pathway. ConclusionsOS displays increased expression of the GABAergic neuronal marker GAD1, and 3-MPA significantly reduces OS growth by inhibiting the Wnt/β-catenin pathway.

Fabrication and characterization of bifunctional PCL/chitosan scaffolds decorated with MXene nanoflakes for bone tissue engineering

The implantation of bioresorbable compositions has emerged as a promising therapeutic strategy to treat damaged bone tissues. To develop versatile bone scaffolds, polycaprolactone (PCL) is known as a dominant polymeric material regarding its unique biocompatibility and biodegradability. However, using PCL in a single structure reveals insufficient mechanical properties, in tandem with poor biological activity. To modulate these features, the combination of PCL and chitosan has been broadly proposed due to the proper bioactivity behavior of the chitosan component. It is also declared that the presence of MXene elements in the bone scaffolds could enhance the osteogenic impact and modify the mechanical behavior to match the surrounding bone tissue. To explore the synergetic effect of chitosan and MXene in enhancing the features of PCL structure, the PCL/chitosan/MXene ternary system was designed in this study. Accordingly, MXene nanosheets were synthesized and incorporated with various filler contents of 1, 3, and 5 % into PCL/chitosan to boost the overall characteristics. The obtained data exhibited a rise in porosity ratio from 22 to 30 % and a decrease in contact angle from 95.45 to 79.86⁰ by embedding MXene up to 3 %. Young's modulus was enhanced from 0.4 to 1.2 MPa, corroborating the generation of scaffolds with superior mechanical strength and rigidity. The compositions containing MXene up to 3 % revealed no cytotoxicity and human osteoblast cell assay approved the cell adhesion affinity of the designed architectures. Furthermore, the presence of MXene nanosheets resulted in the promoting of antimicrobial features in the membranes as a bifunctional behavior. Correspondingly, embedding an optimized ratio of MXene nanoparticles into the PCL/chitosan scaffold could create a suitable scaffolding architecture toward the generation of new bone tissues, benefiting appropriate cell attachment, proliferation, and differentiation.

Chondrocyte Invasion May Be a Mechanism for Persistent Staphylococcus Aureus Infection In Vitro.

Recurrent bone and joint infection with Staphylococcus aureus is common. S. aureus can invade and persist in osteoblasts and fibroblasts, but little is known about this mechanism in chondrocytes. If S. aureus were able to invade and persist within chondrocytes, this could be a difficult compartment to treat. Can S. aureus infiltrate and persist intracellularly within chondrocytes in vitro? Cell lines were cultured in vitro and infected with S. aureus. Human chondrocytes (C20A4) were compared with positive controls of human osteoblasts (MG63) and mouse fibroblasts (NIH3T3), which have previously demonstrated S. aureus invasion and persistence (human fibroblasts were not available to us). Six replicates per cell type were followed for 6 days after infection. Cells were treated daily with antibiotic media for extracellular killing. To determine whether S. aureus can infiltrate chondrocytes, fluorescence microscopy was performed to qualitatively assess the presence of intracellular bacteria, and intracellular colony-forming units (CFU) were enumerated 2 hours after infection. To determine whether S. aureus can persist within chondrocytes, intracellular CFUs were enumerated from infected host cells each day postinfection. S. aureus invaded human chondrocytes (C20A4) at a level (2.8 x 10 5 ± 5.5 x 10 4 CFUs/mL) greater than positive controls of human osteoblasts (MG63) (9.5 x 10 2 ± 2.5 x 10 2 CFUs/mL; p = 0.01) and mouse fibroblasts (NIH3T3) (9.1 x 10 4 ± 2.5 x 10 4 CFUs/mL; p = 0.02). S. aureus also persisted within human chondrocytes (C20A4) for 6 days at a level (1.4 x 10 3 ± 5.3 x 10 2 CFUs/mL) greater than that of human osteoblasts (MG63) (4.3 x 10 2 ± 3.5 x 10 1 CFUs/mL; p = 0.02) and mouse fibroblasts (NIH3T3) (0 CFUs/mL; p < 0.01). S. aureus was undetectable within mouse fibroblasts (NIH3T3) after 4 days. There were 0 CFUs yielded from cell media, confirming extracellular antibiotic treatment was effective. S. aureus readily invaded human chondrocytes (C20A4) in vitro and persisted viably for 6 days after infection, evading extracellular antibiotics. Chondrocytes demonstrated a greater level of intracellular invasion and persistence by S. aureus than positive control human osteoblast (MG63) and mouse fibroblast (NIH3T3) cell lines. Chondrocyte invasion and persistence may contribute to recurrent bone and joint infections. Additional research should assess longer periods of persistence and whether this mechanism is present in vivo.

Surface modification of Ti40Cu40Zr11Fe3Sn3Ag3 amorphous alloy for enhanced biocompatibility in implant applications

This study focuses on the design of a new Ti based multicomponent amorphous alloy for the development of biocompatible implant materials with enhanced hemocompatibility and cytocompatibility. While this class of amorphous alloys has shown its potential for biomedical implant applications, there are major concerns due to the presence of elements such as copper which can lead to cytotoxicity in the human body during long term implantation. Nevertheless, copper is indispensable in the development of an amorphous alloy. Thus, the objective of this work is to selectively remove copper from the surface of the Ti40Cu40Zr11Fe3Sn3Ag3 (at%) amorphous alloy using the dealloying technique and produce a patterned protective passivated surface rich in Ti and Zr oxides. Nitric acid (HNO3) has been found to be effective in depleting copper from the sample surface. Optimization of treatment parameters such as temperature (70 °C and room temperature) yielded drastic differences in the morphology of the samples studied using Field-Emission Scanning Electron Microscopy. The treated sample surface demonstrated good hemocompatibility and cytocompatibility with primary human osteoblast cells (HOb) and human osteosarcoma cell line (Saos-2). Additionally, the treated samples showed higher ability to produce reactive oxygen species with respect to pristine samples, which could be convenient for preserving the implant from bacterial contamination. These findings contribute to the advancement of producing copper-depleted nanostructured Ti based amorphous alloys for biomedical implant applications.

Biological Activities of Deer Antler-Derived Peptides on Human Chondrocyte and Bone Metabolism.

Orally administered "tortoiseshell and deer antler gelatin" is a common traditional medicine for patients with osteoporosis or osteoarthritis. From the pepsin-digested gelatin, we previously isolated and identified the osteoblast-stimulating pentapeptide, TSKYR. Its trypsin digestion products include the dipeptide YR, enhancing calcium ion uptake, and tripeptide TSK, resulting in remarkable 30- and 50-fold increases in mineralized nodule area and density in human osteoblast cells. These peptides were chemically synthesized in this study. The composition of deer antler preparations comprises not only proteins and peptides but also a significant quantity of metal ion salts. By analyzing osteoblast growth in the presence of peptide YR and various metal ions, we observed a synergistic effect of calcium and strontium on the effects of YR. Those peptides could also stimulate the growth of C2C12 skeletal muscle cells and human chondrocytes, increasing collagen and glycosaminoglycan content in a three-dimensional environment. The maintenance of bone homeostasis relies on a balance between osteoclasts and osteoblasts. Deer antler peptides were observed to inhibit osteoclast differentiation, as evidenced by ROS generation, tartrate-resistant acid phosphatase (TRACP) activity assays, and gene expression in RAW264.7 cells. In summary, our findings provide a deep understanding of the efficacy of this folk medicine.

Negative Regulation of LINC01013 by METTL3 and YTHDF2 Enhances the Osteogenic Differentiation of Senescent Pre-Osteoblast Cells Induced by Hydrogen Peroxide.

Senescent pre-osteoblasts have a reduced ability to differentiate, which leads to a reduction in bone formation. It is critical to identify the keys that regulate the differentiation fate of senescent pre-osteoblasts. LINC01013 has an essential role in cell stemness, differentiation, and senescence regulation. This study aims to examine the role and mechanism of LINC01013 in regulating osteogenic differentiation in senescent human embryonic osteoblast cell line (hFOB1.19) cells induced by hydrogen peroxide (H2O2). The results show that LINC01013 decreased alkaline phosphatase activity, mineralization of hFOB1.19 cells in vitro, and the expression of collagen II, osteocalcin, and bone sialoprotein. LINC01013 knockdown enhances the osteogenesis of hFOB1.19 cells and rescues osteogenic differentiation impaired by H2O2. METTL3 negatively regulates LINC01013 expression, enhancing hFOB1.19 cells' osteogenesis in vitro and in vivo. METTL3 overexpression can enhance hFOB1.19 cells' osteogenic differentiation impaired by H2O2. YTHDF2 promotes LINC01013 decay, facilitating osteogenic differentiation. YTHDF2 overexpression rescues hFOB1.19 cells osteogenic differentiation impaired by H2O2. Taken together, METTL3 upregulates osteogenic differentiation by inhibiting LINC01013, and YTHDF2 accelerates LINC01013 degradation, reducing its inhibitory effect. This study highlights LINC01013 as a key regulator in the fate switching process of senescent hFOB1.19 cells, impacting osteogenic differentiation.

Optimization and analysis of sustainable magnesium-based alloy (Mg-Zn-Ca-Y) for biomedical applications

Due to strength and biodegradability, magnesium (Mg) and its alloys are potential biodegradable implant materials. However, pure Mg corrodes more rapidly in the physiological environment, causing rapid deterioration before bone repair. The discrepancy between bone healing and Mg implant deterioration encourages the development of new Mg alloys with other acceptable alloying elements to achieve the desired high corrosion resistance and mechanical properties. In this work, different concentrations of yttrium (Y), that is, Mg-4zn-0.2ca-xY, (x= 3,6,9,12% wt), are added to Mg-based alloys. The microstructure, mechanical characteristics, corrosion behavior, and biocompatibility of the alloys were carefully investigated. When Y concentrations are high, Mg alloys with Y change significantly. High Y concentrations in Mg alloys containing yttrium (Y) suppress intermetallic phases along grain boundaries and form chemically stable Y oxide layers on the surfaces, changing their microstructures and improving their corrosion resistance. Cytotoxicity analysis showed that human osteoblast cells were not significantly affected by the Y-containing Mg alloys. The benefits of using Y as an alloying element to simultaneously adjust Mg alloys with higher strength and slower deterioration are presented.

In Vitro Biocompatibility Assessment of a Novel Membrane Containing Magnesium-Chitosan/Carboxymethyl Cellulose and Alginate Intended for Bone Tissue Regeneration.

Bone tissue engineering (BTE) is an emerging interdisciplinary field that aims to develop new strategies and materials for repairing, regenerating, or replacing damaged bone tissues. This field combines engineering, biology, and medicine principles to create functional bone tissues in the laboratory and in vivo. The main goal of BTE is to create biological substitutes that mimic the structure, function, and properties of natural bone tissue, thereby promoting the regeneration of bone defects caused by trauma, disease, or aging. In this study, we developed a biocomposite membrane using magnesium-chitosan, carboxymethyl cellulose, and alginate through a simple cast drying method. The biocompatibility of the membrane was evaluated using human osteoblastic cells, and it was found to be nontoxic to these cells. Both metabolic activity measurements (24 and 48 hours) and the lactate dehydrogenase release assay (72 hours) indicated that the membrane was biocompatible and did not exert significant toxic effects. These results suggest that the developed biocomposite membrane has the potential to be used as a safe and effective biomaterial for various biomedical applications, such as BTE, wound healing, and drug delivery. Further studies are warranted to explore the full potential of this membrane and its performance in different biological environments.

Characterization of hFOB 1.19 Cell Line for Studying Zn-Based Degradable Metallic Biomaterials.

In vitro testing is the first important step in the development of new biomaterials. The human fetal osteoblast cell line hFOB 1.19 is a very promising cell model; however, there are vast discrepancies in cultivation protocols, especially in the cultivation temperature and the presence of the selection reagent, geneticin (G418). We intended to use hFOB 1.19 for the testing of Zn-based degradable metallic materials. However, the sensitivity of hFOB 1.19 to zinc ions has not yet been studied. Therefore, we compared the toxicity of zinc towards hFOB 1.19 under different conditions and compared it with that of the L929 mouse fibroblast cell line. We also tested the cytotoxicity of three types of Zn-based biomaterials in two types of media. The presence of G418 used as a selection reagent decreased the sensitivity of hFOB 1.19 to Zn2+. hFOB 1.19 cell line was more sensitive to Zn2+ at elevated (restrictive) temperatures. hFOB 1.19 cell line was less sensitive to Zn2+ than L929 cell line (both as ZnCl2 and extracts of alloys). Therefore, the appropriate cultivation conditions of hFOB 1.19 during biomaterial testing should be chosen with caution.