Bioactive electrospun chitosan/magnesium-doped hydroxyapatite nanocomposite scaffold co-loaded with icariin, lithium chloride and naringin for enhanced osteogenesis, antibacterial activity and bone regeneration in vitro and in vivo
The bioactive chitosan/Mg-HAp nanocomposite scaffold effectively promotes bone regeneration by enhancing osteogenic signaling pathways and exhibits strong potential for bone tissue engineering applications.
This study aimed to develop a cost‐effective bone tissue engineering scaffold that mimics the native bone environment without relying on exogenous recombinant growth factors. A chitosan/magnesium‐doped hydroxyapatite nanocomposite scaffold incorporating icariin, lithium chloride, and naringin was fabricated via freeze‐drying and comprehensively characterized. Physicochemical analyses (FTIR, XRD, SEM) confirmed an interconnected porous architecture with porosity exceeding 85%, appropriate mechanical strength, and controlled biodegradability. In vitro assays using SAOS‐2 cells demonstrated favorable cytocompatibility, enhanced osteoblast proliferation, and notable antibacterial activity. In vivo, a rat calvarial defect model over 12 weeks revealed significantly improved bone defect closure and trabecular bone formation in treated groups compared with blank controls. Histological findings were supported by molecular analyses indicating activation of the Wnt/β‐catenin signaling pathway as a key mechanism underlying the osteogenic response to the incorporated bioactive agents. Collectively, these results indicate that chitosan/Mg‐HAp scaffolds enriched with icariin, lithium chloride, and naringin exhibit an advantageous combination of structural, mechanical, biological, and antimicrobial properties, and effectively promote bone regeneration without the need for expensive recombinant growth factors, highlighting their potential as advanced biomimetic scaffolds for clinical bone repair applications.
S.M. Hefzollesan, H. Musayeva, Hamed Aghazadeh et al.· Journal of Applied Polymer S...· 0 citations
Osteochondral defects have become a common clinical problem. The cartilage-bone interface is complex, and regenerative biomaterials are limited. This is the first study to integrate Continuous plastic flow synthesis (CPFS) derived Zn-doped hydroxyapatite into an electrospun PVA nanofibrous membrane for osteochondral repair. Combined structural and spectroscopic analysis revealed a preserved apatite lattice after zinc integration, with a strong inorganic-polymeric interfacial interaction. The fabricated membrane exhibited smooth nanofibers with an average diameter of 272 ± 2.21 nm, in which Zn-HA was uniformly dispersed. The nanofibrous membrane exhibited considerably better antibacterial efficacy against Staphylococcus aureus and Pseudomonas aeruginosa than Zn-HA. In vitro results confirmed good viability of osteoblasts. In vivo assessment in an osteochondral defect model revealed nearly complete defect repair after 8 weeks, with well-organized trabecular bone formation and restoration of the bone-cartilage structure without a significant inflammatory response. Collectively, these findings reveal synergistic osteoregenerative and antibacterial activity, suggesting that the nanofibrous membrane may serve as a potential material for osteochondral tissue engineering.
Sadaf Ameen, Aneela Anwar, Javeria Zahid et al.· European Journal of Pharmace...· 0 citations
The development of multifunctional scaffolds capable of orchestrating the complex cascade of bone regeneration, cell recruitment, vascularization, and extracellular matrix deposition remains a significant challenge in regenerative medicine. This study introduces a dual-strategy biomaterial system. On one hand, pure monetite (CaP), cobalt-doped monetite (CoCaP), and magnesium-doped monetite (MgCaP) powders were synthesized via coprecipitation to deliver specific ionic cues. On the other hand, these bioactive powders were incorporated into a thermosensitive chitosan/β-glycerophosphate (β-GP) hydrogel to create an injectable, conformable composite. Then, comprehensive physicochemical characterization (X-ray diffraction, Raman, Fourier transform infrared (FTIR), and scanning electron microscopy/energy dispersive spectroscopy) confirmed phase-pure monetite with successful ionic incorporation. FTIR analysis of the hydrogels revealed characteristic bands for chitosan, with evidence of the establishment of electrostatic interactions between protonated amino groups and phosphate species. The composite hydrogels exhibited shear-thinning behavior, storage modulus (G′) exceeding loss modulus (G″), and tunable mechanical properties, with MgCaP composites displaying the highest stiffness. Indirect contact assays on CoCaP powders and hydrogels confirmed enhanced cell adhesion, migration, and expression of pro-angiogenic genes and matrix metalloproteinases. MgCaP formulations robustly upregulated osteogenic markers. Additionally, direct cell contact with composite hydrogels dramatically amplified transcriptional responses on adhesion, cell cycle, and osteogenic genes, particularly on MgCaP hydrogels. Altogether, this work demonstrates that ionic doping confers distinct and complementary bioactivities to monetite, pro-angiogenic/migratory Co2+, and osteogenic/matrix-synthetic Mg2+, and that chitosan hydrogels represent an injectable vehicle that amplifies bioactive signaling upon direct cell contact, thus offering a versatile and innovative platform for bone tissue engineering.
G. S. de Almeida, Matheus Luquirini Santos, Maria Gabriela Jacheto Carra et al.· ACS Biomaterials Science &am...· 0 citations
Background Critical-sized calvarial defects remain challenging because conventional grafting strategies often fail to conform to irregular defect geometries and insufficiently regulate the immune–osteogenic microenvironment. This study developed an injectable MgFe-layered double hydroxide (LDH)-reinforced gelatin methacryloyl (GelMA) hydrogel and compared it with MgAl-LDH to evaluate the influence of LDH cation composition on calvarial bone regeneration. Methods MgFe-LDH and MgAl-LDH nanoplatelets were synthesized and incorporated into photocrosslinkable GelMA hydrogels. Nanoparticle characterization, cellular uptake, cytocompatibility, macrophage responses, and bone marrow stromal cell osteogenic differentiation were evaluated in vitro. Regenerative efficacy was further assessed in a murine critical-sized calvarial defect model for 12 weeks using micro-computed tomography, histology, immunofluorescence staining, qRT-PCR, and transcriptomic analysis. Results Both LDH formulations showed comparable nanoplatelet morphology, positive surface charge, efficient cellular internalization, and favorable cytocompatibility. Compared with LPS-stimulated macrophages, MgFe-LDH reduced TNF-α and IL-1β expression by 55.7% and 57.8%, respectively, while increasing IL-10 and TGF-β expression by 4.2-fold and 3.9-fold. MgFe-LDH also enhanced BMSC osteogenic differentiation, increasing ALP activity, mineralized matrix deposition, RUNX2 expression, and OCN expression by 2.3-fold, 1.7-fold, 2.4-fold, and 1.8-fold, respectively. In vivo, GelMA–MgFe-LDH produced the strongest defect bridging and mineralized tissue formation, increasing BV/TV and BMD by 1.5-fold and 1.6-fold compared with GelMA alone. Transcriptomic and qRT-PCR analyses suggested that IL-10RA–JAK1–STAT3-associated signaling may participate in MgFe-LDH-mediated osteoimmune remodeling and bone repair. Conclusion MgFe-LDH-reinforced injectable GelMA hydrogels promote calvarial bone regeneration and are associated with pro-resolving immune responses and osteogenic remodeling. These findings support cation-engineered LDH hydrogels as promising injectable biomaterials, although pathway inhibition, protein-level validation, ion-release profiling, and long-term biosafety studies are needed to clarify the proposed mechanism.
Jiajie Zheng, Kang Wang, Hao Xu et al.· International Journal of Nan...· 0 citations
3D-printed gelatin scaffolds are widely explored for bone regeneration due to their excellent biocompatibility and biodegradability, yet their clinical translation is severely hindered by several inherent defects, including weak mechanical stability, fast in vivo biodegradation, limited osteogenic capability, and the absence of anti-infective functions. Globally, it remains a key challenge in bone tissue engineering to develop integrated scaffold systems that simultaneously satisfy mechanical matching, long-term biological activity, and anti-pathogenic requirements. To address this challenge, a multifunctional CHm/PCA/Cu2+/ε-PL@Gel-OCS scaffold with enhanced mechanical properties, outstanding antibacterial, anti-inflammatory, pro-vascularization and osteogenic activities was developed via cryogenic 3D printing of a gelatin (Gel)/oxidized chondroitin sulfate (OCS) composite ink loaded with chitosan microspheres surface-functionalized by protocatechuic aldehyde (PCA), copper ions (Cu2+) and ε-polylysine (ε-PL). Scanning electron microscopy and energy-dispersive X-ray analysis confirmed uniform dispersion of the microspheres and sustained release of therapeutic agents as the scaffold degraded. Rheological and mechanical testing demonstrated excellent print fidelity, interconnected porosity (161 ± 37 μm pores), and compressive strengths (100-200 MPa) suitable for cortical bone repair. Such porous structure and mechanical performance are highly compatible with human cortical bone microenvironment, which facilitates cell infiltration, nutrient exchange and mechanical load bearing. In vitro release studies revealed a sequential sustained release profile (OCS > Cu2+ > ε-PL), ensuring a sustainable osteogenic, angiogenic, anti-inflammatory and antibacterial activity. The scaffold achieved 100% bactericidal efficiency against both Staphylococcus aureus and Escherichia coli, suppressed protein denaturation (anti-inflammation), and promoted neovascularization in a chick chorioallantoic membrane assay. Biocompatibility assays using MC3T3-E1 osteoblasts showed enhanced cell adhesion, proliferation, and live/dead viability over 5 days. Osteogenic potential was significantly elevated on the multifunctional scaffold, as evidenced by time-dependent increases in ALP activity, mineral deposition (Alizarin Red S), and upregulated expression of ALP, RUNX2, OPN, and OCN genes compared with Gel and Gel-OCS controls. Taken together, our cryogenic 3D-printed Gel-OCS scaffold incorporating PCA/Cu2+/ε-PL-functionalized chitosan microspheres provides a single-step, customizable platform that combines robust mechanical properties with multi-modal therapeutic functionalities. Different from conventional single-function bone scaffolds reported in most international studies, this multi-component synergistic design successfully realizes the integration of mechanical reinforcement, antibacterial, anti-inflammatory, vascularization and osteogenesis functions in one system. These promising preclinical results highlight a novel therapeutic strategy for bone defect regeneration, it solves the common bottlenecks of traditional gelatin-based bone scaffolds, provides a feasible and universal fabrication strategy for high-performance multifunctional bone repair materials, and offers new insights for the global development and clinical translation of 3D-printed bone tissue engineering scaffolds.
Jialing Zhuang, Shunyu Chen, Xiufeng Xiao· International Journal of Bio...· 0 citations
The developed scaffold showed higher cell viability value than control groups than control groups, and confirmed cells proliferation potential of the scaffold at prolonged times, and future studies should explore in vivo performance and long-term functionality of the scaffold.
Ali Khalaji, Soheila Zare, Faranak Aghaz et al.· Scientific Reports· 0 citations