Search Results (366)

Despite metals currently being widely used in orthopedic surgery, their mechanical properties significantly differ from the surrounding tissues and organs, causing low biocompatibility. Biodegradable, non-toxic, and non-immunogenic materials seem to be more convenient for clinical implementation. Our research was aimed at the construction of a polylactide screw covered with collagen, nanohydroxyapatite, and polylactide, with a variant including silver nanowires for antibacterial properties, as well as the analysis of their physico-chemical and biological properties. Adherent human osteosarcoma cells (2T line) were shown to grow on the porous surface layers. A cytotoxicity assay using WST1 revealed the non-toxic nature of the coatings and showed an increase in cell adhesion and proliferation. Safety and efficacy were also evaluated in vivo with the coated screws implanted into the metatarsal bones of minipigs. Histological analysis at 29 and 58 days post-screw-implantation revealed that the coated samples accelerated bone tissue regeneration compared to uncoated controls. This was evidenced by a higher bone-to-granulation tissue ratio, reduced inflammatory cell counts, and increased osteoblast/osteoclast activity at the early stage during the initial days after implantation. The results confirm that the developed bioactive coatings enhance biocompatibility and osteointegration. Full article

Osseointegration in dental implants involves the use of materials that mimic the bone tissue, with special properties such as biocompatibility and biodegradability. In this study, we describe the preparation and characterization of composites based on collagen, chondroitin sulfate, and sage oil obtained by freeze-drying method. Their morphological structures were determined by water uptake and scanning electron microscopy, the physical–chemical interactions between components by FT-IR, the stability by in vitro collagenase degradation, and the results indicate that the samples’ properties are highly influenced by the hydrophobic and hydrophilic character of sage essential oil and chondroitin sulfate, respectively, concluding that we can design a formulation with certain properties. The composite spongious forms were evaluated for cytocompatibility using the MG63 osteoblast cell line and subjected to histological observation. The results showed that the samples with sage essential oil were most resistant to enzymatic degradation, and the ones with chondroitin sulfate promoted the deposition of an abundant extracellular matrix. Taken together, the results suggest that incorporating chondroitin sulfate and sage oil in a controlled manner into collagen scaffolds represents a promising approach for enhancing bone tissue regeneration. Full article

Background/Objectives: The purpose of this study was to assess the in vitro biocompatibility and corrosion resistance of five titanium alloys that have been recently developed for dental implant applications, whose compositions were designed to align with current approaches in the development of novel biomaterials. Priority was given to limiting the harmfulness associated with specific chemical elements present in common conventional alloys and increasing corrosion resistance to improve the biomaterial–tissue cellular interaction. Methods: For this purpose, five types of titanium alloys with original chemical compositions (Ti1–Ti5) were developed. The electrochemical behavior of the alloys was analyzed by evaluating the corrosion resistance in environments that simulate the oral environment, as well as the cellular behavior, by evaluating the viability, growth, and proliferation of human cells on osteoblasts and gingival fibroblasts. Detailed analysis of the chemical composition by scanning electron microscope (SEM/EDS) methods was used. The corrosion rate of the alloys in artificial saliva was tested using the polarization resistance technique (Tafel). Human osteoblasts (hFOB cell line) and human gingival fibroblasts (hFIB-G cell line) were used to measure biocompatibility in vitro. Results: The Ti5 alloy demonstrated the highest cell viability and the lowest corrosion rate (0.114 μm/year) among all tested compositions, with the Ti3 alloy containing Mo and Zr following closely behind. The Ti2 alloy exhibited reduced biocompatibility because of the inclusion of Ni and Fe in its composition. Conclusions: Taken together, the results of this study provide useful information on the basic characteristics of titanium alloys with original chemical compositions. The titanium alloys were analyzed in comparison with common conventional alloys (Cp–Ti and Ti6Al4V) as well as alloys such as Ti–Zr, Ti–Nb, and Ti–Nb–Zr–Ta, which are considered to be viable alternatives to conventional materials for making dental implants. Full article

Background/Objectives: Fibrodysplasia Ossificans Progressiva (FOP) is a rare genetic bone disorder, leading to progressive immobilization through the formation of bone in muscles, tendons, and ligaments. A variant in the ACVR1 gene results in a constitutively overactive ALK2 receptor, leading to the aberrant activation of the SMAD1/5/9 pathway. This activation occurs not only in response to Activin A, which does not normally activate this pathway, but also through heightened sensitivity to BMP ligands and even in the absence of ligand binding. This dysregulated signaling ultimately drives the formation of heterotopic ossification. The inhibition of the altered ALK2 receptor holds promise as a potential treatment strategy that is currently being investigated in several trials. In this study, we performed an in vitro characterization of novel kinase inhibitor KTI-2338 with high selectivity for the ALK2 receptor. Methods: Dermal human FOP and control fibroblasts were cultured in osteogenic medium with and without the inhibitor to assess the effect on transdifferentiation into osteoblast-like cells. Results: Compound KTI-2338 elicited effects consistent with inhibiting aberrant Activin A signaling and receptor sensitization, through reductions in osteogenic markers and pSMAD1/5/9 expression levels. In line with this, a pattern of reduced Alizarin Red staining was observed following treatment with the compound, indicating reduced mineralization. Conclusions: These findings indicate that kinase inhibitor KTI-2338 disrupts the pathological processes underlying FOP and may offer a new therapeutic option for this devastating disease. Full article

Objective: This study aimed to elucidate the regulatory mechanisms of the long intergenic non-protein coding RNA 02381 (LINC02381)/microRNA-let-7g-5p (let-7g-5p)/thrombospondin 1 (THBS1) signaling axis in osteosarcoma (OS). Methods: The expression levels of LINC02381, let-7g-5p, and THBS1 were quantified in OS and adjacent normal tissues via reverse transcription quantitative polymerase chain reaction. Their correlations with clinicopathological features were analyzed. Expression patterns were further validated in OS cell lines (143B, U-2OS, Saos-2, MNNG-HOS, MG-63) and normal osteoblast cell line hFOB1.19. The molecular interaction between LINC02381 and let-7g-5p and the targeting relationship of let-7g-5p with THBS1 were verified via dual-luciferase reporter and RNA pull-down assays. Functional effects were assessed using cell counting kit-8, colony formation, Transwell migration, and xenograft tumor models. Results: Compared to adjacent normal tissues, LINC02381 and THBS1 were upregulated in OS tissues (fold change > 3.0, p < 0.001), while let-7g-5p was downregulated (fold change ≈ 0.038, p < 0.001). Similar expression trends were observed in U-2OS cells. Knockdown of LINC02381 or overexpression of let-7g-5p reduced cell proliferation, colony formation, migration, THBS1 expression, and tumor volume (p < 0.001). These inhibitory effects were partially reversed by let-7g-5p inhibitors, restoring cell viability and migration by approximately 70%. Mechanistically, LINC02381 functioned as a competing endogenous RNA (ceRNA), directly binding to let-7g-5p and mitigating its suppression of THBS1. Conclusions:LINC02381 promotes OA progression by acting as a ceRNA for let-7g-5p, thereby upregulating THBS1 expression. This signaling axis represents a potential therapeutic target for OS. Full article

Chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings were synthesized in order to address the need for biomaterials with improved physico-chemical and biological properties for biomedical applications. Both chromium-doped hydroxyapatite (7CrHAp) and chromium-doped hydroxyapatite in chitosan matrix (7CrHAp-CH) coatings could represent promising materials for biomedical applications due to their superior properties. This study aims to evaluate the physico-chemical and in vitro biological properties of 7CrHAp and 7CrHAp-CH coatings to determine the impact of chitosan incorporation on the physico-chemical and biological features. The results reported in this study indicate that addition of chitosan improves surface uniformity and biological properties, highlighting their potential for uses in biomedical applications. In this study, coatings of chromium-doped hydroxyapatite (7CrHAp, with x_Cr = 0.07) and its composite variant embedded in a chitosan matrix (7CrHAp-CH) were systematically analyzed using a suite of characterization techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and metallographic microscopy (MM). The results of the XRD analysis revealed that the average crystal size was 19.63 nm for 7CrHAp and 16.29 nm for 7CrHAp-CH, indicating a decrease in crystallite size upon CH incorporation. The films were synthesized via the dip coating method using stable suspensions, whose stability was assessed through ultrasonic measurements (double-distilled water serving as the reference medium). The values obtained for the stability parameter were 2.59·10⁻⁶ s⁻¹ for 7CrHAp, 8.64·10⁻⁷ s⁻¹ for 7CrHAp-CH, and 3.14·10⁻⁷ s⁻¹ for chitosan (CH). These data underline that all samples are stable: CH is extremely stable, followed by 7CrHAp-CH (very stable) and 7CrHAp (stable). The in vitro biocompatibility of the 7CrHAp and 7CrHAp-CH coatings was evaluated with the aid of the MG63 cell line. The cytotoxic potential of these coatings towards MG63 cells was quantified using the MTT assay after 24 and 48 h of incubation. Our results highlight that both 7CrHAp and 7CrHAp-CH coatings exhibit high biocompatibility with MG63 cells, maintaining cell viability above 90% at both incubation times, thus supporting osteoblast-like cell proliferation. Furthermore, the antimicrobial efficacy of both 7CrHAp and 7CrHAp-CH samples was evaluated in vitro against the Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa) reference strain. The in vitro antibacterial activity of the 7CrHAp and 7CrHAp-CH coatings was further evaluated against Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa), Escherichia coli ATCC 25922 (E. coli) and Staphylococcus aureus ATCC 25923 (S. aureus) reference strains. In addition, atomic force microscopy (AFM) analysis was also used to investigate the ability of P. aeruginosa, E. coli and S. aureus cells to adhere and to develop colonies on the surfaces of the 7CrHAp and 7CrHAp-CH coatings. The results from the biological assays indicate that both coatings exhibit promising antibacterial properties, highlighting their potential for being used in biomedical applications, particularly in the development of novel antimicrobial devices. Full article

Magnesium oxide nanoparticles, or MgO NPs, have garnered a lot of attention because of their exceptional stability, biocompatibility, and antibacterial properties. However, many of the green production methods used today have limited mechanistic knowledge and low reproducibility. In order to get over these challenges, we created a standardized and environmentally friendly process for producing MgO NPs using orange peel extract, a naturally occurring biowaste source rich in phytochemicals that acts as a stabilizing and reducing agent. Active precursor alteration during synthesis was clearly shown by X-ray diffraction (XRD) and thermal analysis (TGA-FTIR), while imaging techniques showed extremely crystalline cubic-phase MgO nanoparticles that were about 9 nm in size. The NPs displayed an irregular shape between 10 and 40 nm and a positive surface charge of +11.74 mV. Terpenoids, polymethoxyflavones, fatty acids, and sugars all work in collaboration with direct nucleation, regulate particle growth, and stabilize the nanoparticles, according to GC-MS analysis. The MgO NPs showed remarkable cytocompatibility in biology, preserving >80% viability in fibroblast and osteoblast cell lines while causing distinct metabolic regulation in osteoblasts without changing the shape of the cells. Consistent moderate activity against a variety of pathogens was confirmed by antimicrobial and antibiofilm assays, with special effectiveness against Gram-positive bacteria and Pseudomonas aeruginosa biofilms. This study shows that these MgO NPs have good biocompatibility and antimicrobial qualities, indicating the need for more research for possible biomedical applications. It also clarifies the molecular role of phytochemicals in nanoparticle formation and provides a repeatable green synthesis pathway. Full article

Despite the rising incidence of osteoporosis (the most common bone disorder) as life expectancy increases worldwide, the genetic and metabolic factors contributing to this multifactorial disease are still poorly understood. This study investigated the role of arginine metabolism in bone formation and its potential for preventing bone loss in postmenopausal osteoporosis. The osteogenic effects of arginine were evaluated in vitro by determining calcium mineral deposition and the expression of marker genes in the human osteoblastic cell line Saos-2. In vivo analyses were conducted in ovariectomized mice treated with arginine, focusing on femoral bone microarchitecture, marker gene expression and serum metabolite profiles. Arginine treatment enhanced calcium deposition and osteoblastic differentiation in vitro. In contrast, however, this treatment had a deleterious effect in vivo, exacerbating trabecular bone loss. These results are particularly relevant given the wide availability of arginine as a dietary supplement, and our findings underscore the necessity of verifying the safety of nutritional supplements in different populations and in the presence of disease. Full article

The hyperbaric environment, to which many categories of workers are exposed, can provoke injuries that can lead to various types of disorders. A major part of the studies aiming to explore the causes/effects leading to these injuries are conducted in vivo. In the present manuscript, we describe the effects on osteoblast cell cultures stressed in a hyperbaric purpose-built chamber, using an in vitro model to analyze the affected pathways. A hyperbaric chamber for cell cultures was constructed by adapting a pressurized test chamber originally designed for technical use. The MG-63 cell line and human primary osteoblasts were placed into this chamber at different atm and exposure times, at 37 °C. After treatment, the chamber was depressurized by performing controlled decompression stops. Then, the pro-inflammatory cytokines and bone tissue biomarker expression were analyzed. The stress conditions induced the overexpression of pro-inflammatory cytokines, such as IL-6, IL-1β, and TNF-α, along with reactive oxygen species release. Moreover, the alteration of bone tissue marker production was observed. In particular, the increase in Receptor Activator of NF-κB Ligand (RANKL) and the decrease in Osteoprotegerin (OPG) were detected. Further modulation was observed regarding other biomarkers, Alkaline phosphatase, Osteocalcin, Bone Morphogenetic Protein-2, and mainly Collagen type I, all of which were downregulated by treatment. Taken together, these findings account for certain illnesses, such as dysbaric osteonecrosis, diagnosed in workers exposed to a hyperbaric environment. Inflammation induced by this kind of stress affects several factors involved in bone tissue homeostasis, leading to bone injuries, which are among the typical disorders observed in divers. Full article

The global burden of cancer continues to grow, with bone cancer—though rare—posing serious challenges in terms of treatment and post-surgical reconstruction. Autologous bone grafting remains the gold standard, yet limitations such as donor site morbidity drive the search for alternative solutions. Tissue engineering, combining biomaterials and therapeutic agents, offers promising avenues. This study focuses on the development of multifunctional scaffolds based on collagen and hydroxyapatite obtained by the freeze-drying technique and incorporating both synthetic (doxorubicin) and natural (caffeic acid) compounds for osteosarcoma treatment. These scaffolds aim to combine tumor inhibition with bone regeneration, addressing the dual need for local drug delivery and structural repair in bone cancer therapy. The characterization of these composite materials revealed that a spongious structure with interconnected pores and a homogeneous pore distribution, with pore sizes between 20 and 250 μm suitable for osteoblasts infiltration. The Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) and X-ray diffraction (XRD) analyses confirmed the formation of hydroxyapatite inside the collagen matrix. LDH and XTT assays confirmed that the antitumoral scaffolds possess great potential for osteosarcoma treatment, showing that after 3 days of culturing, the extracts containing doxorubicin-7A, both alone and in combination with caffeic acid-9A, significantly reduced the viability of cell lines to below 7% and 20%, respectively. Full article

Proinflammatory cytokines such as IL-1β, IL-6, and TNF-α are key mediators of inflammatory bone loss and are commonly described as inhibitors of osteoblast function. However, their effects on osteogenesis remain controversial, likely due to the differences in the cell models and experimental settings in in vitro studies. We recently showed that these cytokines significantly enhanced the mineralization of primary human osteoblast-like cells (OBs). Here, we provide the first analysis of cytokine effects on the osteogenesis of the widely used human osteoblastic cell line hFOB 1.19 and compare them to primary OBs. Unexpectedly, all three cytokines significantly inhibited mineralization in hFOB 1.19 cells without affecting the proliferation. IL-1β and TNF-α also suppressed ALP activity, whereas IL-6 acted ALP-independent but increased the osteogenic marker expression despite the reduced mineralization, indicating a possible uncoupled differentiation and mineralization. Morphological and transcriptional analyses indicated that hFOB 1.19 cells represent an earlier osteogenic differentiation stage, while primary OBs show phenotypic heterogeneity and donor-dependent expression profiles. These data demonstrate that proinflammatory cytokines can have severely different effects on the osteogenesis of different cell models, supported by the highly contradictory findings reported in the literature. Nevertheless, elucidating the mechanisms underlying the inhibition of osteogenesis in hFOB 1.19 cells may provide important insights into the cell model and differentiation-stage-specific cytokine effects. Full article

Cartilage-derived migratory cells show great potential for autologous use in cartilage repair surgery. However, their collection through arthroscopic biopsy has not been previously reported in individuals without osteoarthritis. This study aimed to characterize migratory cartilage cells isolated from arthroscopic biopsies of volunteers without osteoarthritis and compare them with cells obtained by enzymatic digestion. Cell cultures were successfully established using both methods—enzymatic digestion and cell migration—from cartilage explants, with no significant differences observed in stem cell markers or plasticity between the cell lines. Cells derived from both procedures exhibited characteristics of mesenchymal stem cell, including fibroblast-like morphology, expression of CD29, CD90, and CD105 markers, absence of hematopoietic and endothelial cell markers, and the ability to differentiate into adipocytes, chondrocytes, and osteoblasts under appropriate conditions. Cells obtained by migration showed lower expression of collagen I and II, along with reduce collagen II/collagen I ratio, both positively associated with chondral matrix production, as well as lower RUNX2 expression. However, no differences were found in the levels of SOX9, essential for chondrogenic differentiation, or in the expression of perlecan gene. Syndecan-1 expression was lower in cells obtained by migration. In conclusion, this study demonstrates that cartilage-derived migratory cells can be successfully obtained from arthroscopic biopsies of individuals without osteoarthritis, presenting comparable dedifferentiation and plasticity profiles. Furthermore, these cells express essential chondrogenic markers and proteins. Although further in vivo studies are needed to determine their effective regenerative potential, cartilage-derived migratory cells represent a promising avenue for cartilage repair strategies. Full article

Innovation in oral implantology is constantly on the move, with a constant search for new biomaterials to overcome many of the limitations of the biomaterials used in current implantable medical devices. This study explores the biocompatibility of an innovative 5% calcium-to-zirconia (Ca-SZ) coating deposited by PVD on TA6V substrates for use in oral implantology. In order to determine the contribution of the Ca-SZ coating, an in vitro biocompatibility study was carried out to assess the potential influence of the Ca-SZ coating (1) on the viability and proliferation of saos-2 and HaCaT cells over a short-term exposure period of 96 h, (2) on the synthesis of pro-inflammatory cytokines, and (3) on the synthesis of osteogenic differentiation markers over a long-term exposure period of 21 days, in comparison with reference biomaterials. The sampling consisted of n = 3 biological replicates, and a p-value of <0.05 was used as the threshold for statistical significance. Viability and proliferation kinetics to WST-1 and CyQUANT NF, respectively, showed improved viability/proliferation of Ca-SZ exposed to both cell lines independently. The TNF-alpha and IL-6 assays revealed reduced levels of cytokines compared with the reference biomaterials, including the control groups. In parallel, in Saos-2 cells exposed to Ca-SZ for 21 days under osteogenic conditions increased expression of osteogenic markers, such as the synthesis of soluble collagens, alkaline phosphatase (ALP), osteopontin, and osteocalcin, reflecting dynamic and facilitated osteoblastic differentiation, which was supported by the formation of hydroxyapatite (HA) crystals observed by SEM micrograph and confirmed by EDS mapping. In conclusion, Ca-SZ demonstrates an overall better biocompatibility compared with reference biomaterials, linked to a bioactive interaction of calcium, promoting cell proliferation and differentiation for optimal osteointegration, underlining its potential as a relevant innovation for next-generation implants. Full article

Developing scaffolds with a three-dimensional porous structure and adequate mechanical properties remains a key challenge in tissue engineering of bone. These scaffolds must be biocompatible and biodegradable to effectively support osteoblastic cell attachment, metabolic activity, and differentiation. This study successfully fabricated a chitosan–bacterial cellulose (CS–BC) composite scaffold using the solvent casting/particle leaching (SCPL) technique, with NaOH/urea solution and sodium chloride crystals as the porogen. The scaffold exhibited a well-distributed porous network with pore sizes ranging from 300 to 500 µm. Biodegradation tests in PBS containing lysozyme revealed a continuous degradation process, while in vitro studies with MC3T3-E1 cells (pre-osteoblastic mouse cell line) demonstrated excellent cell attachment, as observed through SEM imaging. The scaffold also promoted increased metabolic activity (OD values) in the MTT assay, and enhanced alkaline phosphatase (ALP) activity and upregulated expression of osteogenic-related genes. These findings suggest that the CS–BC composite scaffold, fabricated using the SCPL method, holds great potential as a candidate for bone tissue engineering applications. Full article

Background/Objectives: In this paper, we report the development of the first chrome-doped hydroxyapatite in a poly (vinyl alcohol) (PVA) matrix enriched with amoxicillin for biomedical applications. The development of chromium-doped hydroxyapatite coatings in a PVA matrix enriched with amoxicillin aims to provide new biomaterials with improved physico-chemical and biological properties, making them promising candidates for biomedical applications. Methods: Through ultrasound studies, we obtained valuable information on the stability of the samples. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, metallographic microscopy (MM), and atomic force microscopy (AFM) were employed for the characterization of the samples. The biocompatibility of the CrHApAPV and CrHApAPV-Ax coatings was assessed using the MG63 human osteoblast-like cell line. To evaluate the cytotoxic potential of these coatings, the cell viability was quantified using the MTT assay after 24 h of incubation. The antibacterial activity of the coatings was evaluated with the aid of the reference strain Pseudomonas aeruginosa ATCC 27853 (P. aeruginosa). Results: The XRD patterns of CrHApAPV and CrHApAPV-Ax samples were examined to evaluate the effects of PVA and amoxicillin on the lattice parameters, unit cell volume, and average crystallite sizes. The results of the in vitro antibacterial assay demonstrated that both the CrHApAPV and CrHApAPV-Ax coatings exhibited very good antibacterial properties for all the tested time intervals. Conclusions: Our results underline the stability of the analyzed samples. Moreover, our physico-chemical and biological studies highlight that CrHApAPV and CrHApAPV-Ax coatings could be considered promising materials for biomedical uses. Full article