Odontogenesis by Endocytosis of Peptide Embedding Bioactive Glass Composite

Antimicrobial Peptide- and Dentin Matrix-Functionalized Hydrogel for Vital Pulp Therapy via Synergistic Bacteriostasis, Immunomodulation, and Dentinogenesis

The preservation of vital pulps is crucial for maintaining the physiological functions of teeth; however, vital pulp therapy (VPT) of pulpitis teeth remains a substantial challenge due to uncontrolled infection, excessive inflammation, and limited regenerative potential. Current pulp capping agents have restricted effects in the infectious and inflammatory microenvironment. To address this, a multifunctional hydrogel (TGH/DM) with antibacterial, immunomodulatory, and mineralization-promoting effects is designed. The antimicrobial peptide (AMP) and demineralized dentin matrix are incorporated into the hydrogel, achieving sustainable delivery of AMP and a cocktail of growth factors. In vitro results show that TGH/DM could kill endodontic microbiota, ameliorate inflammatory responses of human dental pulp stem cells (hDPSCs), and prompt odontogenic differentiation of inflammatory hDPSCs via activation of peroxisome proliferator-activated receptor gamma. In vivo results suggest that TGH/DM is capable of inducing M2 phenotype transformation of macrophages in mice and fostering the regeneration of the dentin-pulp complex in inflamed pulps of beagle dogs. Overall, this study first proposes the synergistic regulation of AMP and tissue-specific extracellular matrix for the treatment of pulpitis, and the advanced hydrogel provides a facile and effective way for VPT.

Bioactive ceramic-based materials: beneficial properties and potential applications in dental repair and regeneration

Bioactive ceramics, primarily consisting of bioactive glasses, glass-ceramics, calcium orthophosphate ceramics, calcium silicate ceramics and calcium carbonate ceramics, have received great attention in the past decades given their biocompatible nature and excellent bioactivity in stimulating cell proliferation, differentiation and tissue regeneration. Recent studies have tried to combine bioactive ceramics with bioactive ions, polymers, bioactive proteins and other chemicals to improve their mechanical and biological properties, thus rendering them more valid in tissue engineering scaffolds. This review presents the beneficial properties and potential applications of bioactive ceramic-based materials in dentistry, particularly in the repair and regeneration of dental hard tissue, pulp-dentin complex, periodontal tissue and bone tissue. Moreover, greater insights into the mechanisms of bioactive ceramics and the development of ceramic-based materials are provided.

Engineering mesoporous bioactive glasses for emerging stimuli-responsive drug delivery and theranostic applications

Mesoporous bioactive glasses (MBGs), which belong to the category of modern porous nanomaterials, have garnered significant attention due to their impressive biological activities, appealing physicochemical properties, and desirable morphological features. They hold immense potential for utilization in diverse fields, including adsorption, separation, catalysis, bioengineering, and medicine. Despite possessing interior porous structures, excellent morphological characteristics, and superior biocompatibility, primitive MBGs face challenges related to weak encapsulation efficiency, drug loading, and mechanical strength when applied in biomedical fields. It is important to note that the advantageous attributes of MBGs can be effectively preserved by incorporating supramolecular assemblies, miscellaneous metal species, and their conjugates into the material surfaces or intrinsic mesoporous networks. The innovative advancements in these modified colloidal inorganic nanocarriers inspire researchers to explore novel applications, such as stimuli-responsive drug delivery, with exceptional in-vivo performances. In view of the above, we outline the fabrication process of calcium-silicon-phosphorus based MBGs, followed by discussions on their significant progress in various engineered strategies involving surface functionalization, nanostructures, and network modification. Furthermore, we emphasize the recent advancements in the textural and physicochemical properties of MBGs, along with their theranostic potentials in multiple cancerous and non-cancerous diseases. Lastly, we recapitulate compelling viewpoints, with specific considerations given from bench to bedside.

Novel biomimetic peptide-loaded chitosan nanoparticles improve dentin bonding via promoting dentin remineralization and inhibiting endogenous matrix metalloproteinases

OBJECTIVE

This study aims to synthesize novel chitosan nanoparticles loaded with an amelogenin-derived peptide QP5 (TMC-QP5/NPs), investigate their remineralization capability and inhibitory effects on endogenous matrix metalloproteinases (MMPs), and evaluate the dentin bonding properties of remineralized dentin regulated by TMC-QP5/NPs.

METHODS

TMC-QP5/NPs were prepared by ionic crosslinking method and characterized by dynamic light scattering method, scanning electron microscopy, transmission electron microscope, atomic force microscope, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The encapsulation and loading efficiency of TMC-QP5/NPs and the release of QP5 were examined. To evaluate the remineralization capability of TMC-QP5/NPs, the mechanical properties, and the changes in structure and composition of differently conditioned dentin were characterized. The MMPs inhibitory effects of TMC-QP5/NPs were explored by MMP Activity Assay and in-situ zymography. The dentin bonding performance was detected by interfacial microleakage and microshear bond strength (μSBS).

RESULTS

TMC-QP5/NPs were successfully synthesized, with uniform size, good stability and biosafety. The encapsulation and loading efficiency of TMC-QP5/NPs was respectively 69.63 ± 2.22% and 13.21 ± 0.73%, with a sustained release of QP5. TMC-QP5/NPs could induce mineral deposits on demineralized collagen fibers and partial occlusion of dentin tubules, and recover the surface microhardness of dentin, showing better remineralization effects than QP5. Besides, TMC-QP5/NPs significantly inhibited the endogenous MMPs activity. The remineralized dentin induced by TMC-QP5/NPs exhibited less interfacial microleakage and higher μSBS, greatly improved dentin bonding.

SIGNIFICANCE

This novel peptide-loaded chitosan nanoparticles improved resin-dentin bonding by promoting dentin remineralization and inactivating MMPs, suggesting a promising strategy for optimizing dentin adhesive restorations.

Upconversion Nanoplatform Enables Multimodal Imaging and Combinatorial Immunotherapy for Synergistic Tumor Treatment and Monitoring

Designing a novel nanoplatform that integrates multimodal imaging and synergistic therapy for precision tumor nanomedicines is challenging. Herein, we prepared rare-earth ion-doped upconversion hydroxyapatite (FYH) nanoparticles as nanocarriers coated and loaded respectively with polydopamine (PDA) and doxorubicin (DOX), i.e., FYH-PDA-DOX, for tumor theranostics. The developed FYH-PDA-DOX complexes exhibited desirable photothermal conversion, pH/near-infrared-irradiation-responsive DOX release, and multimodal upconversion luminescence/computed tomography/magnetic resonance imaging performance and helped monitor the metabolic distribution process of the complexes and provided feedback to the therapeutic effect. Upon 808 nm laser irradiation, the fast release of DOX facilitated the photothermal-chemotherapy effect, immunogenic cell death, and antitumor immune response. On combining with the anti-programmed cell death 1 ligand 1 antibody, an enhanced tri-mode photothermal-chemo-immunotherapy synergistic treatment against tumors can be realized. Thus, this treatment elicited potent antitumor immunity, producing appreciable T-cell cytotoxicity against tumors, amplifying tumor suppression, and extending the survival of mice. Therefore, the FYH-PDA-DOX complexes are promising as a smart nanoplatform for imaging-guided synergistic cancer treatment.

A novel amelogenesis-inspired hydrogel composite for the remineralization of enamel non-cavitated lesions

Enamel non-cavitated lesions (NCLs) are subsurface enamel porosity from carious demineralization. The developed enamel cannot repair itself once NCLs occurs. The regeneration of mineral crystals in a biomimetic environment is an effective way to repair enamel subsurface defects. Previously, an amelogenin-derived peptide named QP5 was proven to repair demineralized enamel. In this work, inspired by amelogenesis, a novel biomimetic hydrogel composite containing the QP5 peptide and bioactive glass (BG) was designed, in which QP5 could promote enamel remineralization by guiding the calcium and phosphorus ions provided by BG. Also, BG could adjust the mineralization micro-environment to alkalinity, simulating the pH regulation of ameloblasts during enamel maturity. The BQ hydrogel composite showed biosafety and possessed capacity for enamel binding, ion release and pH buffering. Enamel NCLs treated with the BQ hydrogel composite showed a higher reduction in lesion depth and mineral loss both in vitro and in vivo. Moreover, compared to the hydrogels containing only BG or QP5, groups treated with the BQ hydrogel composite attained more surface microhardness recovery and color recovery, exhibiting resistance to erosion and abrasion of the remineralization layer. We envision that the BQ hydrogel composite can provide a biomimetic micro-environment to favor enamel remineralization, thus reducing the lesion depth and increasing the mineral content as a promising biomimetic material for enamel NCLs.