Search Results (433)

Myocardial infarction (MI) remains one of the most common cardiovascular diseases and a leading cause of morbidity and mortality worldwide. In recent years, natural polymeric patches have attracted increasing attention as a promising therapeutic platform for myocardial tissue repair. This study explored the fabrication and evaluation of screen-printed electrodes (SPEs) on chitosan film as a novel platform for cardiac patch applications. Chitosan is a biodegradable and biocompatible natural polymer that provides an ideal substrate for SPEs, providing mechanical stability and promoting cell adhesion. Silver ink was employed to enhance electrochemical performance, and the electrodes exhibited strong adhesion and structural integrity under wet conditions. Mechanical testing and swelling ratio analysis were conducted to assess the patch’s physical robustness and aqueous stability. Silver ink was employed to enhance electrochemical performance, which was evaluated using cyclic voltammetry. In vitro, electrical stimulation through the chitosan–SPE patch significantly increased the expression of cardiac-specific genes (GATA-4, β-MHC, troponin I) in bone marrow mesenchymal stem cells (BMSCs), indicating early cardiogenic differentiation potential. In vivo, the implantation of the chitosan–SPE patch in a rat MI model demonstrated good tissue integration, preserved myocardial structure, and enhanced ventricular wall thickness, indicating that the patch has the potential to serve as a functional cardiac scaffold. These findings support the feasibility of screen-printed electrodes fabricated on chitosan film substrates as a cost-effective and scalable platform for cardiac repair, offering a foundation for future applications in cardiac tissue engineering. Full article

Multiple myeloma (MM) is an incurable malignancy characterized by the proliferation of abnormal plasma cells within the bone marrow, followed by potential dissemination to extramedullary sites. The bone marrow barrier (BMB) plays a pivotal role in plasma cell homing and disease progression. Bone marrow endothelial cells (BMECs) and bone marrow stromal cells (BMSCs), through their interactions with MM cells, secrete adhesion molecules, angiogenic cytokines, anti-apoptotic factors, and growth-promoting signals that support MM cell survival and proliferation. This review examines the components of the BMB and the major pathways involved in MM pathogenesis. Targeting the interactions between MM cells and the BMB may offer novel therapeutic opportunities. Full article

Osteolforte, a compound with potential bone-regenerative properties, was investigated for its effects on human bone marrow stromal cells (hBMSCs). This study aimed to evaluate its impact on cell viability, osteogenic differentiation, and both gene and protein expression using a combination of assays, including CCK-8, Alizarin Red S staining, Quantitative Real-Time PCR (qRT-PCR), and Western blot analysis. The results demonstrated that Osteolforte significantly enhanced osteogenic differentiation in hBMSCs. Alizarin Red S staining revealed increased mineralization, indicating elevated calcium deposition. Gene expression analysis showed an upregulation of key osteogenic markers, including runt-related transcription factor-2 (RUNX-2), collagen type I (COL-1), and bone morphogenetic protein-2 (BMP-2), supporting the role of Osteolforte in promoting osteoblastic activity. In particular, the elevated expression of RUNX-2—a master transcription factor in osteoblast differentiation along with COL-1, a major bone matrix component, and BMP-2, a key bone morphogenetic protein—highlights the compound’s osteogenic potential. In conclusion, Osteolforte enhances early-stage osteogenesis and mineralization in hBMSCs and represents a promising candidate for bone regeneration. Full article

To improve implant osseointegration while preventing infection, we developed a strontium (Sr)-doped Ti₃C₂T_x MXene coating on titanium, aiming to synergistically enhance bone integration and antibacterial performance. MXene is a family of two-dimensional transition-metal carbides/nitrides whose abundant surface terminations endow high hydrophilicity and bioactivity. The coating was fabricated via anodic electrophoretic deposition (40 V, 2 min) of Ti₃C₂T_x nanosheets, followed by SrCl₂ immersion to incorporate Sr²⁺. The coating morphology, phase composition, chemistry, hydrophilicity, mechanical stability, and Sr²⁺ release were characterized. In vitro bioactivity was assessed with rat bone marrow mesenchymal stem cells (BMSCs)—with respect to viability, proliferation, migration, alkaline phosphatase (ALP) staining, and Alizarin Red S mineralization—while the antibacterial efficacy was evaluated against Staphylococcus aureus (S. aureus) via live/dead staining, colony-forming-unit enumeration, and AlamarBlue assays. The Sr-doped MXene coating formed a uniform lamellar structure, lowered the water-contact angle to ~69°, and sustained Sr²⁺ release (0.36–1.37 ppm). Compared to undoped MXene, MXene/Sr enhanced BMSC proliferation on day 5, migration by 51%, ALP activity and mineralization by 47%, and reduced S. aureus viability by 49% within 24 h. Greater BMSCs activity accelerates early bone integration, whereas rapid bacterial suppression mitigates peri-implant infection—two critical requirements for implant success. Sr-doped Ti₃C₂T_x MXene thus offers a simple, dual-function surface-engineering strategy for dental and orthopedic implants. Full article

Purpose: Collagen membranes with biomimetic mineralization are emerging as promising materials for bone regeneration, owing to their high biocompatibility. In this study, we developed a biogenic collagen membrane by combining citrate (C) pretreatment and carboxymethyl chitosan (CMC)-mediated mineralization and further evaluated its bone healing potential. Methods: C-CMC collagen membranes were prepared by lyophilization. The mineral composition and content were tested through X-ray diffraction (XRD), Fourier transform infrared (FTIR), and thermogravimetric analysis (TGA). The micromorphology was observed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and scanning probe microscopy (SPM). Physical and mechanical properties, including the swelling rate, porosity, hydrophilicity, tensile strength, Young’s modulus, degradation, and barrier function, were also evaluated. Bone mesenchymal stem cells (BMSCs) were cultured in vitro to observe their behavior. An in vivo critical-size rat calvarial defect model was used to validate the effects of the membrane on bone regeneration. Results: The C-CMC collagen membrane was successfully synthesized as a collagen–hydroxyapatite complex with intrafibrillar mineralization, exhibiting improved mechanical properties and an optimal swelling rate, porosity, hydrophilicity, and degradation rate. Additionally, the C-CMC collagen membrane promoted BMSC proliferation, adhesion, and osteogenesis while preventing epithelial cell infiltration. In vivo experiments indicated that C-CMC collagen membranes significantly stimulated bone regeneration without causing systemic toxicity. Conclusions: Our findings suggest that the C-CMC collagen membrane possesses satisfactory physical and mechanical properties, along with good biocompatibility and efficacy in bone defect regeneration, making it a potential candidate for a bioactive guided bone regeneration membrane in clinical applications. Full article

This study investigated the effects of local fibroblast growth factor (FGF)-2 application on periodontal healing in an osteoporotic model, both in vivo and in vitro. Wistar rats were divided into the ovariectomy (OVX) and Control groups. Periodontal defects were created 8 weeks post-OVX and treated with hydroxypropylcellulose (HPC) or FGF-2 + HPC. Healing was evaluated through micro-computed tomography and histological analyses at 2 and 4 weeks. In vitro, bone marrow mesenchymal stromal cells (BMSCs) were cultured with/without FGF-2 and assessed for cell morphology, viability/proliferation, and osteoblastic marker expression. Alkaline phosphatase (ALP) staining was also performed. FGF-2-treated defects in both groups showed significantly greater bone volume fraction, trabecular number, and thickness compared to HPC only. Histologically, FGF-2 enhanced new bone formation, with the greatest levels in the Control group. In vitro, OVX BMSCs showed reduced actin staining versus controls. FGF-2 increased cell viability/proliferation and protrusions in both groups while downregulating Alpl and Bglap expression levels and reducing ALP-positive cells. FGF-2 increased new bone formation in the OVX group, stimulated proliferation of OVX BMSCs, and modulated their differentiation. FGF-2 could enhance periodontal healing even under osteoporotic conditions, albeit to a lesser extent. Full article

Background/Objectives: Although the nanocomposite of poly(L-lactic acid) with graphene oxide (PLLA-GO) shows promise for tissue engineering, its specific bioactive interactions with diverse cell lineages during early tissue regeneration remain unclear. This study comprehensively investigated the in vitro multifaceted biocompatibility of PLLA-GO using human fibroblasts (FN1 cells), murine mesenchymal stem cells (mBMSCs), and human umbilical vein endothelial cells (HUVECs). Methods: Morphological analyses were performed using optical and scanning electron microscopy, while proliferation dynamics were assessed via CFSE staining. Cell cycle progression was evaluated using flow cytometry, mitochondrial activity was examined through TMRE staining, and inflammatory cytokine profiling was performed via Cytometric Bead Array (CBA). Results: PLLA-GO exhibited primary biocompatibility across all evaluated cell lines, characterized by efficient adhesion and proliferation. However, significant cell-type-dependent modulations were observed. The FN1 cells exhibited proliferative adaptation but induced accelerated scaffold degradation, as evidenced by a substantial increase in cellular debris (5.93% control vs. 34.38% PLLA-GO; p = 0.03). mBMSCs showed a transient initial proliferative response and a significant 21.66% increase in TNF-α production (179.67 pg/mL vs. 147.68 pg/mL in control; p = 0.03). HUVECs demonstrated heightened mitochondrial sensitivity, exhibiting a 32.19% reduction in mitochondrial electrical potential (97.07% control vs. 65.82% PLLA-GO; p ≤ 0.05), alongside reductions in pro-inflammatory cytokines TNF-α (8.73%) and IL-6 (12.47%). Conclusions: The PLLA-GO processing method is crucial for its properties and subsequent cellular interactions. Therefore, rigorous and specific preclinical evaluations—considering both cellular contexts and fabrication—are indispensable to ensure the safety and therapeutic potential of PLLA-GO in tissue engineering and regenerative medicine. Full article

Poly(vinylidene fluoride-trifluoroethylene) (PVTF) nanoparticles coatings with electrically heterogeneous microdomains were engineered to mimic the natural electromechanical microenvironment of bone tissue, offering a novel strategy to enhance osteogenesis. Through a biphasic solvent phase separation method, PVTF nanoparticles (NPs) were synthesized and spin-coated onto substrates, followed by melt-recrystallization to achieve high β-phase crystallinity. The substrates were then subjected to corona poling, a process involving high-voltage corona discharge to electrically polarize and align the molecular dipoles. Structural and electrical characterization revealed tunable microdomain surface potentials and piezoelectric coefficients, correlating with enhanced hydrophilicity. Notably, microdomain potential—produced by controlled polarization—was shown to directly regulate cellular responses. In vitro studies demonstrated that a corona-poled PVTF NP coating significantly improved bone marrow mesenchymal stem cell (BMSC) proliferation and early osteogenic differentiation. This work establishes a surface electropatterning approach and highlights the critical role of electrical heterogeneity in bone regeneration, offering a novel strategy for bioactive biomaterial design. Full article

To improve the construction performance of inorganic adhesives used for bonding fiber-reinforced polymer (FRP) sheets to reinforce concrete structures, make rational use of resources, and reduce carbon emissions, double-shear tests on the interface bonding performance between bonded FRP sheets and cement mortar test blocks, as well as four-point bending tests on bonded carbon fiber-reinforced polymers (CFRPs) to reinforce concrete beams, were conducted using basic magnesium sulfate cement (BMSC) as the adhesive. The influence laws of parameters, such as the type of FRP sheet and the number of FRP sheet bonding layers on the shear performance of the bonding interface between BMSC and cement mortar test blocks, were investigated, as well as the influence laws of the number of CFRP sheet bonding layers and the type of binder on the bending performance of CFRP sheet-reinforced beams. The test results show that the ultimate load of CFRP-reinforced beams bonded with BMSC as the binder increased by 17.4% to 44.4% compared with the unreinforced beams and simultaneously improved the flexural stiffness and crack-limiting ability of the reinforced beams. The failure of the reinforced beam begins with the separation of the CFRP sheet from the concrete at the middle and bottom of the beam span. When the CFRP sheet of the reinforced beam is one layer and two layers, the flexural bearing capacity reaches 91.4% and 96%, respectively, of the reinforced beam, with epoxy resin as the binder under the same conditions. With the increase in the number of CFRP layers, the flexural bearing capacity of the reinforced beam improves, but the increased flexural bearing capacity does not increase proportionally with the increase in the number of sheet layers. By introducing the influence coefficient of BMSC on the flexural bearing capacity (FBC) of reinforced beams, based on the test results, the formula for calculating the FBC of concrete beams, which are reinforced with CFRP sheets bonded by BMSC, was developed. After verification, the calculation formulas established in this paper have high accuracy and can provide theoretical references for similar engineering applications. Full article

Osteoarthritis (OA) is a prevalent and debilitating joint disorder that affects a substantial proportion of the global population, underscoring the urgent need for therapeutic strategies that extend beyond symptomatic management. Although mesenchymal stem cells (MSCs) have emerged as a promising therapeutic modality, their clinical application remains constrained by several inherent limitations. This study explores a cell-free alternative by investigating the therapeutic potential of exosomes derived from bone marrow (BMSCs), adipose tissue (ADSCs), and umbilical cord (UMSCs) MSCs in mitigating OA pathogenesis, utilizing both in vitro and ex vivo models. Exosomes from each MSC source were isolated and characterized through nanoparticle tracking analysis, transmission electron microscopy, and Western blotting to confirm their identity and purity. Subsequently, their chondroprotective, anti-inflammatory, and regenerative properties were systematically assessed through evaluations of cell viability, expression profiles of inflammatory and chondroprotective markers, and chondrocyte migration assays. The results demonstrate that all three types of MSC-derived exosomes (MSC-Exos) exhibit low cytotoxicity while significantly suppressing proinflammatory markers and enhancing the expression of chondroprotective genes. Notably, BMSC-Exos and UMSC-Exos displayed superior efficacy in attenuating inflammation, promoting cartilage protection, and inhibiting chondrocyte apoptosis. Furthermore, all MSC-Exos markedly enhanced chondrocyte motility, a critical component of cartilage repair. Collectively, these findings support the therapeutic promise of MSC-Exos, particularly those derived from BMSCs and UMSCs, as a targeted, cell-free approach for the treatment of OA compared to ADSCs. By modulating inflammation, promoting cartilage regeneration, and preventing chondrocyte apoptosis, MSC-Exos may serve as a viable and scalable alternative to current MSC-based therapies for this widespread degenerative disease. Full article

The 2024 outbreak of highly pathogenic avian influenza virus (HPAIV) H5N1 in U.S. dairy cattle presented an unprecedented scenario where the virus infected bovine mammary glands and was detected in milk, raising serious concerns for public health and the dairy industry. Unlike previously described subclinical influenza A virus (IAV) infections in cattle, H5N1 infection induced severe clinical symptoms, including respiratory distress, mastitis, and abnormal milk production. To understand the host immune responses and changes, particularly in the mammary gland, we performed single-cell RNA sequencing analysis on bovine milk somatic cells (bMSCs) in vitro exposed to an H5N1 isolate from an infected dairy farm. We identified ten distinct cell clusters and observed a shift toward type-2 immune responses, characterized by T cells expressing IL13 and GATA3, and three different subtypes of epithelial cells based on the expression of genes associated with milk production. Our study revealed temporal dynamics in cytokine expression, with a rapid decline in luminal epithelial cells and an increase in macrophages and dendritic cells, suggesting a role in increased antigen presentation. While viral RNA was detected in bulk-exposed bMSC samples via qRT-PCR, no viral reads were observed in the scRNA-seq data, indicating that the immune responses captured may be due to exposure to viral components rather than productive infection. This research fills a critical gap in understanding the immune responses of bovine mammary glands to H5N1 exposure and highlights the need for further investigation into therapeutic strategies for managing such outbreaks. Full article

Delayed or non-healing of bone defects in an aging, multi-morbid population is still a medical challenge. Current replacement materials, like autografts, are limited. Thus, artificial substitutes from biodegradable polymers and bioactive glasses (BGs) are promising alternatives. Here, novel cerium-doped mesoporous BG microparticles (Ce-MBGs) with different cerium content were included in photocrosslinkable, methacrylated gelatin (GelMA) for promoting cellular functions of human mesenchymal stem cells (hBMSCs). The composites were studied for intrinsic morphology and Ce-MBGs distribution by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). They were gravimetrically analyzed for swelling and stability, compressive modulus via Microsquisher^® and bioactivity by Fluitest^® calcium assay and inductively coupled plasma-optical emission spectrometry (ICP-OES), also determining silicon and cerium ion release. Finally, seeding, proliferation, and differentiation of hBMSCs was investigated. Ce-MBGs were evenly distributed within composites. The latter displayed a concentration-dependent but cerium-independent decrease in swelling, while mechanical properties were comparable. A MBG type-dependent bioactivity was shown, while an enhanced osteogenic differentiation of hBMSCs was achieved for Ce-MBG-composites and related to different ion release profiles. These findings show their strong potential in promoting bone regeneration. Still, future work is required, e.g., analyzing the expression of osteogenic genes, providing further evidence for the composites’ osteogenic effect. Full article

(1) Background: Osteonecrosis of the femoral head (ONFH), caused by insufficient blood supply, leads to bone tissue death. Current treatments lack effective bone regeneration materials to reverse disease progression. This study introduces an injectable and self-setting 3D porous bioceramic scaffold (Mg@Ca), combining MgO + SiO₂ mixtures with α-hemihydrate calcium sulfate, designed to promote bone repair through in situ pore formation and osteoinduction. (2) Methods: In vitro experiments evaluated human bone marrow mesenchymal stem cell (h-BMSC) proliferation, differentiation, and osteogenic marker expression in Mg@Ca medium. Transcriptome sequencing identified bone development-related pathways. In vivo efficacy was assessed in a rabbit model of ONFH to evaluate bone repair. (3) Results: The Mg@Ca scaffold demonstrated excellent biocompatibility and supported h-BMSC proliferation and differentiation, with significant up-regulation of COL1A1 and BGLAP. Transcriptome analysis revealed activation of the PI3K-Akt signaling pathway, critical for osteogenesis. In vivo results confirmed enhanced trabecular density and bone volume compared to controls, indicating effective bone repair and regeneration. (4) Conclusions: The Mg@Ca scaffold offers a promising therapeutic approach for ONFH, providing a minimally invasive solution for bone defect repair while stimulating natural bone regeneration. Its injectable and self-setting properties ensure precise filling of bone defects, making it suitable for clinical applications. Full article

This study developed electrosprayed deferoxamine (DFO)-loaded poly(lactic-co-glycolic acid) microspheres (DFO-MS) combined with a sucrose acetate isobutyrate (SAIB) depot (DFO-MS@SAIB) for bone-defect repair, targeting the coordinated regulation of angiogenesis and osteogenesis in vascularized bone regeneration—where new blood vessels support functional bone integration. In vitro/in vivo evaluations confirmed its dual pro-angiogenic and pro-osteogenic effects via HIF-1α pathway activation. Background/Objectives: Emerging evidence underscores the indispensability of vascularization in bone-defect repair, a clinical challenge exacerbated by limited intrinsic healing capacity. While autologous grafts and growth-factor-based strategies remain mainstream, their utility is constrained by donor-site morbidity, transient bioactivity, and poor spatiotemporal control over angiogenic–osteogenic coupling. Here, we leveraged DFO, a hypoxia-mimetic HIF-1α stabilizer with angiogenic potential, to engineer an injectable DFO-MS@SAIB depot. This system was designed to achieve sustained DFO release, thereby synchronizing vascular network formation with mineralized tissue regeneration in critical-sized defects. Methods: DFO-MS were fabricated via electrospraying and combined with SAIB (DFO-MS@S) to form an injectable sustained-release depot. Their physicochemical properties, including morphology, encapsulation efficiency, degradation, release kinetics, and rheology, were systematically characterized. In vitro, the angiogenic capacity of HUVECs co-cultured with DFO-MS was evaluated; conditioned HUVECs were then co-cultured with BMSCs to assess the BMSCs’ cytocompatibility and osteogenic differentiation. In vivo bone regeneration in a rat calvarial defect model was evaluated using micro-CT, histology, and immunohistochemistry. Results: The DFO-MS@SAIB system achieved sustained DFO release, stimulating HUVEC proliferation, migration, and tubulogenesis. In a Transwell co-culture model, pretreated HUVECs promoted BMSC migration and osteogenic differentiation via paracrine signaling involving endothelial-secreted factors (e.g., VEGF). HIF-1α pathway activation upregulated osteogenic markers (ALP, Col1a1, OCN), while in vivo experiments demonstrated enhanced vascularized bone regeneration, with significantly increased bone volume/total volume (BV/TV) and new bone area compared with controls. Conclusion: The DFO-MS@SAIB system promotes bone regeneration via sustained deferoxamine release and HIF-1α-mediated signaling. Its angiogenesis–osteogenesis coupling effect facilitates vascularized bone regeneration, thereby offering a translatable strategy for critical-sized bone-defect repair. Full article

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is one of the side effects of bisphosphonate (BP) administration. Despite some preventive measures having been suggested, a definitive and effective treatment strategy for BRONJ remains to be established. Recent evidence has indicated that BPs dramatically impair the function of orofacial bone marrow stromal cells (BMSCs), which may contribute to the development of osteonecrosis. Thus, we hypothesized that recovery-impaired function of BMSCs at lesion sites could be beneficial in treating BRONJ. N6-methyladenosine (m6A) modification is the most common epigenetic modification and has been demonstrated to play a vital role in the modulation of BMSCs’ function. We detected the role of m6A modification in regulating the function of orofacial BMSCs under BP stimulation, and found that BPs led to a reduction in the global m6A methylation level, SAM level, and METTL3 expression in BMSCs during the osteogenic differentiation period. Meanwhile, betaine, a methyl group donor, effectively reversed the BP-decreased global m6A methylation level and SAM level in BMSCs, as well as rescuing the differentiation ability of impaired BMSCs. In the last part, we built a BRONJ rat model and supplemented rats with betaine via drinking water. The results showed that betaine successfully attenuated bone lesions and promoted wound healing in BP-injected rats, thereby providing new insight into future clinical treatment for BRONJ. Full article