Effect of substrate on the response of 3-dimensional periodontal ligament tissue to compressive stimulation.

Purpose: The purpose of this study was to investigate the influence of substrates under the three-dimensional periodontal ligament (3D PDL) tissue on its biological functions after compressive stimulation.

Methods: A 3D PDL tissue was created using a poly(L-lactic acid) (PLLA) porous scaffold impregnated with human periodontal ligament fibroblasts (hPDLFs). It was then placed on a polyetheretherketone (PEEK) substrate, which has a comparable elastic modulus to bone and was compressed (25 g/cm) for 1, 3, and 7 days.

Sustained Fisetin Release Prevents Orthodontic Ti-6Al-4V Screw Failure by Suppressing Peri-Implantitis and Alveolar Bone Resorption.

In clinical practice, mini-screws of titanium-6-aluminum-4-vanadium alloy with an extra low interstitial (ELI) grade (Ti-6Al-4V ELI) are widely used as orthodontic anchorages. However, in orthodontic treatment, Ti-6Al-4V mini-screw failure because of peri-implantitis is a major challenge. To prevent damage caused by peri-implantitis, we developed a novel Ti-6Al-4V disc/screw coated with poly(lactide--glycolide) incorporating fisetin, a naturally occurring flavonoid with anti-inflammatory and antiosteoclastogenic/osteogenic properties.

Optimized human dedifferentiated fat cells from the buccal fat pad-derived osteoinductive extracellular vesicles promote osteoblast differentiation.

Background/purpose: Bone reconstruction in the maxillofacial region typically relies on autologous bone grafting, which presents challenges, including donor site complications and graft limitations. Recent advances in tissue engineering have identified highly pure and proliferative dedifferentiated fat cells (DFATs) as promising alternatives. Herein, we explored the capacity for osteoblast differentiation and the osteoinductive characteristics of extracellular vesicles derived from DFATs (DFAT-EVs).

Enhanced vertical bone augmentation in rat parietal bone using hydroxyapatite-coated polytetrafluoroethylene domes with Erbium Yttrium Aluminum Garnet pulsed laser deposition.

Purpose: To perform vertical bone augmentation on rat parietal bone by coating the inner surface of dense polytetrafluoroethylene (d-PTFE) domes with hydroxyapatite (HA) using Erbium Yttrium Aluminum Garnet (Er:YAG) pulsed laser deposition in a rat model.

Methods: The d-PTFE plate surface, α-tricalcium phosphate (α-TCP) coating, and HA coating were measured using scanning electron microscopy and X-ray diffraction to confirm the replacement of α-TCP with HA via high-pressure steam sterilization. The dome was glued to the center of the rat parietal bone and closed with periosteal and epithelial sutures.

Evaluation of Osteogenic Potential for Rat Adipose-Derived Stem Cells under Xeno-Free Environment.

This study aimed to develop a novel culture method for rat adipose-derived stem cells (rADSC) and evaluate their osteogenic potential. The rADSC cultured in xeno-free culture medium (XF-rADSCs) or conventional culture medium containing fetal bovine serum (FBS-rADSCs) were combined with micropieces of xeno-free recombinant collagen peptide to form 3-dimensional aggregates (XF-rADSC-CellSaic or FBS-rADSC-CellSaic). Both FBS-rADSC and XF-ADSC in CellSaic exhibited multilineage differentiation potential.

Carbonate apatite versus β-tricalcium phosphate for rat vertical bone augmentation: A comparison of bioresorbable bone substitutes using polytetrafluoroethylene tubes.

This study radiologically and histologically compared two bioresorbable bone substitutes with different compositions carbonate apatite (Cytrans Granules; CGs) and β-tricalcium phosphate (β-TCP) for vertical bone augmentation on a rat skull using a polytetrafluoroethylene (PTFE) tubes. This PTFE tube was placed at the center of the skull, fixed with Super Bond, and augmented with CGs or β-TCP granules. Specimens with surrounding tissue were harvested at 4, 8, and 12 weeks postoperatively, and radiological and histological evaluations were performed.

Bioactive Polyetheretherketone with Gelatin Hydrogel Leads to Sustained Release of Bone Morphogenetic Protein-2 and Promotes Osteogenic Differentiation.

Polyetheretherketone (PEEK) is one of the most promising implant materials for hard tissues due to its similar elastic modulus; however, usage of PEEK is still limited owing to its biological inertness and low osteoconductivity. The objective of the study was to provide PEEK with the ability to sustain the release of growth factors and the osteogenic differentiation of stem cells. The PEEK surface was sandblasted and modified with polydopamine (PDA).

Molecular Beacon Imaging System to Discriminate the Differentiation State of Cells from Energy Metabolic Pathways.

Metabolic pathways of energy production play an essential role as a function of cells. It is well recognized that the differentiation state of stem cells is highly associated with their metabolic profile. Therefore, visualization of the energy metabolic pathway makes it possible to discriminate the differentiation state of cells and predict the cell potential for reprogramming and differentiation.

Matrix vesicles promote bone repair after a femoral bone defect in mice.

Matrix vesicles (MtVs) are one of the extracellular vesicles (EVs) secreted by osteoblasts. Although MtVs have a classically-defined function as an initiator of ossification and recent findings suggest a role for MtVs in the regulation of bone cell biology, the effects of MtVs on bone repair remain unclear. In the present study, we employed collagenase-released EVs (CREVs) containing abundant MtVs from mouse osteoblasts.

Senescence-associated secretory phenotypes in rat-derived dedifferentiated fat cells with replicative senescence.

Senescence-associated secretory phenotype (SASPs) secreted from senescent cells often cause the deleterious damages to the surrounding tissues. Although dedifferentiated fat (DFAT) cells prepared are considered a promising cell source for regenerative therapies, SASPs from DFAT cells undergoing long-term cell culture, which latently induce replicative senescence, have barely been explored. The present study was designed to investigate senescent behaviors in rat-derived DFAT cells at high passage numbers and to analyze the possible types of SASPs.

A Reverse Transfection System with Cationized Gelatin Nanospheres Incorporating Molecular Beacon as a Tool to Visualize Cell Function.

The objective of this research is to design a reverse transfection system with cationized gelatin nanospheres (cGNS) incorporating a molecular beacon (MB) to visualize a cell function. The cGNS were prepared by the conventional coacervation method. The MB as an imaging probe was incorporated into the cGNS to prepare imaging complexes (cGNS).

Controlled release of canine MSC-derived extracellular vesicles by cationized gelatin hydrogels.

Introduction: Canine mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) have emerged as a promising form of regenerative therapy. Therapeutic application of EVs remains difficult due to the short half-life of EVs and their rapid clearance from the body. We have developed cationized gelatin hydrogels that prolong the retention of EVs to overcome this problem.

Extracellular vesicles secreted from mouse muscle cells improve delayed bone repair in diabetic mice.

Humoral factors that are secreted from skeletal muscles can regulate bone metabolism and contribute to muscle-bone relationships. Although extracellular vesicles (EVs) play important roles in physiological and pathophysiological processes, the roles of EVs that are secreted from skeletal muscles in bone repair have remained unclear. In the present study, we investigated the effects of the local administration of muscle cell-derived EVs on bone repair in control and streptozotocin-treated diabetic female mice.

Effect of Hydroxyapatite Coating by Er: YAG Pulsed Laser Deposition on the Bone Formation Efficacy by Polycaprolactone Porous Scaffold.

Composite scaffolds obtained by the combination of biodegradable porous scaffolds and hydroxyapatite with bone regeneration potential are feasible materials for bone tissue engineering. However, most composite scaffolds have been fabricated by complicated procedures or under thermally harsh conditions. We have previously demonstrated that hydroxyapatite coating onto various substrates under a thermally mild condition was achieved by erbium-doped yttrium aluminum garnet (Er: YAG) pulsed laser deposition (PLD).

In Vivo Multimodal Imaging of Stem Cells Using Nanohybrid Particles Incorporating Quantum Dots and Magnetic Nanoparticles.

The diagnosis of the dynamics, accumulation, and engraftment of transplanted stem cells in vivo is essential for ensuring the safety and the maximum therapeutic effect of regenerative medicine. However, in vivo imaging technologies for detecting transplanted stem cells are not sufficient at present. We developed nanohybrid particles composed of dendron-baring lipids having two unsaturated bonds (DLU2) molecules, quantum dots (QDs), and magnetic nanoparticles in order to diagnose the dynamics, accumulation, and engraftment of transplanted stem cells, and then addressed the labeling and in vivo fluorescence and magnetic resonance (MR) imaging of stem cells using the nanohybrid particles (DLU2-NPs).

Pioglitazone-incorporated microspheres targeting macrophage polarization alleviates cardiac dysfunction after myocardial infarction.

Objectives: Excessive and chronic inflammation after a myocardial infarction (MI) is associated with left ventricular remodelling and impaired cardiac function. Among inflammatory cells, macrophages play a critical role in polarizing proinflammatory M1 or the reparative M2 subtype. Pioglitazone (PGZ) is reported to regulate macrophage polarization to the M2 subtype.

Irisin improves delayed bone repair in diabetic female mice.

Introduction: Irisin is a proteolytic product of fibronectin type II domain-containing 5, which is related to the improvement in glucose metabolism. Numerous studies have suggested that irisin is a crucial myokine linking muscle to bone in physiological and pathophysiological states.

Materials And Methods: We examined the effects of local irisin administration with gelatin hydrogel sheets and intraperitoneal injection of irisin on the delayed femoral bone repair caused by streptozotocin (STZ)-induced diabetes in female mice.

Design of a Platelet-Mediated Delivery System for Drug-Incorporated Nanospheres to Enhance Anti-Tumor Therapeutic Effect.

The objective of this study is to construct a platelet-mediated delivery system for drug-incorporated nanospheres. Nanospheres of poly(lactic-co-glycolic acid) (PLGA-NS) with different sizes and surface properties were prepared by changing the preparation parameters, such as the type of polymer surfactant, the concentration of polymer surfactant and PLGA, and the stirring rate. When incubated with platelets, PLGA-NS prepared with poly(vinyl alcohol) suppressed the platelet activation.

Intracellular controlled release prolongs the time period of siRNA-based gene suppression.

RNA interference (RNAi) is a gene silencing process by inhibiting a target messenger RNA (mRNA) in the sequence-specific manner in the cell cytoplasm. Small interfering RNA (siRNA) cleaves the target mRNA. However, siRNA is not generally internalized into cells in the native state.

Local application of Usag-1 siRNA can promote tooth regeneration in Runx2-deficient mice.

Runt-related transcription factor 2 (Runx2)-deficient mice can be used to model congenital tooth agenesis in humans. Conversely, uterine sensitization-associated gene-1 (Usag-1)-deficient mice exhibit supernumerary tooth formation. Arrested tooth formation can be restored by crossing both knockout-mouse strains; however, it remains unclear whether topical inhibition of Usag-1 expression can enable the recovery of tooth formation in Runx2-deficient mice.

Extracellular Vesicles Derived From Canine Mesenchymal Stromal Cells in Serum Free Culture Medium Have Anti-inflammatory Effect on Microglial Cells.

Mesenchymal stem/stromal cells (MSCs) have been used as cell sources for treating dogs with naturally-occurring diseases. Extracellular vesicles (EVs) derived from MSCs are now recognized as pivotal to modulating the immune response and supporting tissue repair. Manufacture of MSC-EVs for clinical application mandates removal of the xeno-proteins, including fetal bovine serum.

Visualization of Apoptosis in Three-Dimensional Cell Aggregates Based on Molecular Beacon Imaging.

The objective of this study is to visualize cell apoptosis in three-dimensional (3D) cell aggregates based on molecular beacons (MB). Two types of MB for messenger RNA were used: caspase-3 MB as a target for apoptosis and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) MB as a control of stable fluorescence in cells. To enhance the MB internalization into cells, caspase-3 and GAPDH MB were incorporated in cationized gelatin nanospheres (cGNS), respectively (cGNS and cGNS).

Ultra-small size gelatin nanogel as a blood brain barrier impermeable contrast agent for magnetic resonance imaging.

Magnetic Resonance Imaging (MRI) contrast agents with rapid renal excretion that do not penetrate the blood brain barrier (BBB) and blood cerebrospinal fluid barrier (BCFB) are preferred for safer and low-risk diagnosis. Gadolinium (Gd)-conjugated nanoparticles have been proposed for use as contrast agents; however, the particle size must range between 1 to 7 nm to ensure rapid renal excretion. In this study, three types of gelatin, dissolved in water at varying concentrations of 0.

Complexation design of cationized gelatin and molecular beacon to visualize intracellular mRNA.

The objective of this study is to prepare cationized gelatin-molecular beacon (MB) complexes for the visualization of intracellular messenger RNA (mRNA). The complexes were prepared from cationized gelatins with different extents of cationization and different mixing ratios of MB to cationized gelatin. The apparent size of complexes was almost similar, while the zeta potential was different among the complexes.

Molecular Beacon Imaging to Visualize Ki67 mRNA for Cell Proliferation Ability.

The objective of this study is to visualize the ability of cell proliferation based on molecular beacons (MB). Two types of MB to detect messenger RNA (mRNA) were used. One is a Ki67 MB of a target for cell proliferation ability.