Dual-Colored Janus Microspheres with Photonic and Plasmonic Faces.

Photonic and plasmonic colors, stemming from nanostructures of dielectric materials and metals, are promising for pigment-free coloration. In particular, nanostructures with structural colors have been employed in stimuli-responsive Janus microparticles to provide active color pixels. Here, the authors report a simple strategy to produce electro-responsive Janus microspheres composed of photonic and plasmonic faces for active color change. The photonic microspheres are first prepared by self-assembly of silica particles in emulsion droplets of photocurable resin. The silica particles form 3D crystalline arrays in the interior and 2D hexagonal arrays on the interface. The emulsion droplets are photocured and the silica particles are selectively removed to make porous photonic microspheres with hexagonal arrays of dimples on the surface. Directional deposition of gold or aluminum on the photonic microsphere develops plasmonic color on the top hemisphere while maintaining photonic color on the bottom hemisphere. Moreover, the metal deposited on one side renders the Janus microspheres electro-responsive. Therefore, the photonic and plasmonic colors are switchable by the orientation control of the Janus microspheres with an external electric field. The photonic and plasmonic colors are independently adjustable by employing two different sizes of silica particles in core-shell emulsion drops.

Photonic Microbeads Templated by Oil-in-Oil Emulsion Droplets for High Saturation of Structural Colors.

Photonic microbeads containing crystalline colloidal arrays are promising as a key component of structural-color inks for various applications including printings, paintings, and cosmetics. However, structural colors from microbeads usually have low color saturation and the production of the beads requires delicate and time-consuming protocols. Herein, elastic photonic microbeads are designed with enhanced color saturation through facile photocuring of oil-in-oil emulsion droplets. Dispersions of highly-concentrated silica particles in elastomer precursors are microfluidically emulsified into immiscible oil to produce monodisperse droplets. The silica particles spontaneously form crystalline arrays in the entire volume of the droplets due to interparticle repulsion which is unperturbed by the diffusion of the surrounding oil whereas weakened for oil-in-water droplets. The crystalline arrays are permanently stabilized by photopolymerization of the precursor, forming elastic photonic microbeads. The microbeads are transferred into the refractive-index-matched biocompatible oil. The high crystallinity of colloidal arrays increases the reflectivity at stopband and the index matching reduces incoherent scattering at the surface of the microbeads, enhancing color saturation. The colors can be adjusted by mixing two distinctly colored microbeads. Also, low stiffness and high elasticity reduce foreign-body sensation and enhance fluidity, potentially serving as pragmatic structural colorants for photonic inks.

Improvement of Biological Effects of Root-Filling Materials for Primary Teeth by Incorporating Sodium Iodide.

Therapeutic iodoform (CHI3) is commonly used as a root-filling material for primary teeth; however, the side effects of iodoform-containing materials, including early root resorption, have been reported. To overcome this problem, a water-soluble iodide (NaI)-incorporated root-filling material was developed. Calcium hydroxide, silicone oil, and NaI were incorporated in different weight proportions (30:30:X), and the resulting material was denoted DX (D5~D30), indicating the NaI content. As a control, iodoform instead of NaI was incorporated at a ratio of 30:30:30, and the material was denoted I30. The physicochemical (flow, film thickness, radiopacity, viscosity, water absorption, solubility, and ion releases) and biological (cytotoxicity, TRAP, ARS, and analysis of osteoclastic markers) properties were determined. The amount of iodine, sodium, and calcium ion releases and the pH were higher in D30 than I30, and the highest level of unknown extracted molecules was detected in I30. In the cell viability test, all groups except 100% D30 showed no cytotoxicity. In the 50% nontoxic extract, D30 showed decreased osteoclast formation compared with I30. In summary, NaI-incorporated materials showed adequate physicochemical properties and low osteoclast formation compared to their iodoform-counterpart. Thus, NaI-incorporated materials may be used as a substitute for iodoform-counterparts in root-filling materials after further (pre)clinical investigation.

Structural Coloration with Nonclose-Packed Array of Bidisperse Colloidal Particles.

Colloidal crystals and glasses have their own photonic effects. Colloidal crystals show high reflectivity at narrowband, whereas colloidal glasses show low reflectivity at broadband. To compromise the opposite optical properties, a simple means is suggested to control the colloidal arrangement between crystal and glass by employing two different sizes of silica particles with repulsive interparticle potential. Monodisperse silica particles with repulsive potential spontaneously form crystalline structure at volume fraction far below 0.74. When two different sizes of silica particles coexist, the arrangement of silica particles is significantly influenced by two parameters: size contrast and mixing ratio. When the size contrast is small, a long-range order is partially conserved in the entire mixing ratio, resulting in a pronounced reflectance peak and brilliant structural color. When the size contrast is large, the long-range order is rapidly reduced along with mixing ratio. Nevertheless, a short-range order survives, which causes low reflectivity at a broad wavelength, developing faint structural colors. These findings offer an insight into controlling the colloidal arrangements and provide a simple way to tune the optical property of colloidal arrays for structural coloration.

Is augmentation with the long head of the biceps tendon helpful in arthroscopic treatment of irreparable rotator cuff tears?

BACKGROUND: Although various surgical techniques have been used to treat irreparable rotator cuff tears (RCTs), debate remains regarding which treatment is most effective. The purpose of our study was to compare the outcomes of partial rotator cuff repair versus repair with augmentation of the tenotomized long head of the biceps tendon (LHBT). METHODS: This study included 76 patients with large to massive RCTs. Arthroscopic rotator cuff repair with LHBT augmentation was performed in 39 patients (group I), while partial repair was performed in 37 patients (group II). Clinical and functional outcomes were compared with a visual analog scale for pain and the American Shoulder and Elbow Surgeons score, Constant score, and Korean Shoulder Score. Magnetic resonance imaging was performed 12 months after surgery. RESULTS: The mean follow-up period was 29.6 ± 7.8 months (range, 24-51 months). Significant improvements in pain and clinical scores were observed in both groups at the last follow-up. However, there were no significant differences in pain, clinical scores, or range of motion between the 2 groups at any time point. Retears were observed in 16 patients in group I (41.0%) and 14 in group II (37.8%, P = .78). Augmented LHBT pathology was observed in 10 patients (25.6%). CONCLUSIONS: Both partial repair and repair with LHBT augmentation were effective in improving clinical and radiologic outcomes. No significant differences in clinical outcomes or repaired cuff integrity were observed between the groups. The investment of operation time and effort in augmenting the LHBT in the treatment of irreparable RCTs is not recommended.

Caries Prevalence in Korean Children and Adolescents from 2000 to 2012.

OBJECTIVES: National oral health data is required to assess a population's oral health needs, monitor oral health, plan effective intervention community programs and health policies, and evaluate progress toward health objectives. The study aimed to estimate the prevalence, severity, and inequality in dental caries distribution among Korean young people. STUDY DESIGN: Trained, calibrated examiners at the Korea Ministry of Health & Welfare conducted epidemiological surveys in 2000, 2006, and 2012 during which dental caries were assessed according to World Health Organization (WHO) diagnostic criteria. Decayed, missing, and filled surface and tooth (DMFS/DMFT) indices were estimated. RESULTS: DMFT indices decreased in all regions between 2000 and 2012, with values of 3.3, 2.2, and 1.8 for 12-year-old children in 2000, 2006, and 2012, respectively. The prevalence of caries was higher among female versus male subjects and in rural versus urban areas. CONCLUSIONS: Despite the observed decrease in caries experience indicators in Korea, the caries prevalence remains considerably higher than that in European countries and than the targets set by WHO within the Health21 policy framework. Therefore, Korea apparently retains further potential for caries reduction. Community-based oral disease prevention programs are urgently needed to promote oral health.

17ß-estradiol exerts anticancer effects in anoikis-resistant hepatocellular carcinoma cell lines by targeting IL-6/STAT3 signaling.

17ß-Estradiol (E2) has been proven to exert protective effects against HCC; however, its mechanism on HCC proliferation and suppression of invasion remains to be further explored. Because HCC up-regulates serum Interleukin-6 (IL-6) levels and Signal Transducer and Activator of Transcription 3 (STAT3), molecular agents that attenuate IL-6/STAT3 signaling can potentially suppress HCC development. In this study, we examined involvement of E2 in anoikis resistance that induces invasion capacities and chemo-resistance. Huh-BAT and HepG2 cells grown under anchorage-independent condition were selected. The anoikis-resistant (AR) cells showed stronger chemo-resistance against sorafenib, doxorubicin, 5-fluorouracil and cisplatin compared to adherent HCC cells. AR HCC cells exhibited decreased expression of E-cadherin and increased expression of the N-cadherin and vimentin compared to adherent HCC cells. We then demonstrated that E2 suppressed cell proliferation in AR HCC cells. IL-6 treatment enhanced invasive characteristics, and E2 reversed it. Regarding mechanism of E2, it decreased in the phosphorylation of STAT3 that overexpressed on AR HCC cells. The inhibitory effect of E2 on cell growth was accompanied with cell cycle arrest at G2/M phase and caspase-3/9/PARP activation through c-Jun N-terminal Kinase (JNK) phosphorylation. Taken together, these findings suggested that E2 inhibited the proliferation of AR HCC cells through down-regulation of IL-6/STAT3 signaling. Thus, E2 can be a potential therapeutic drug for treatment of metastatic or chemo-resistant HCC.

The effect of Lactobacillus casei extract on cervical cancer cell lines.

AIM OF THE STUDY: Lactobacillus casei (L. casei) has been shown to inhibit the proliferation of several types of cancer in vivo, but its effect on cervical cells has not been reported. We incubated cells of the human cervical cell lines Caski and HeLa with extracts of L. casei and investigated its effects on the growth of the cells and possible synergy with anticancer drugs. MATERIAL AND METHODS: Cell-free extracts of L. casei were prepared and purified. Cultures of Caski and HeLa cells adhering to tissue culture plates were treated with L. casei extract. The effects of L. casei extract on the growth of cancer cells and its possible synergy with anti-cancer drugs in cervical cancer cell lines were investigated. The cells were treated with L. casei extract alone, anti-cancer drugs alone [doxorubicin, paclitaxel, 5-fluorouracil (5-FU), and cisplatin], or L. casei extract plus anti-cancer drugs. RESULTS: L. casei extract had no significant effect on the growth rate of the two cell lines. Anti-cancer drugs alone induced growth inhibition, but there was no synergistic effect of L. casei extract on growth inhibition. CONCLUSIONS: L. casei extract does not have a potent effect on the viability of cervical cancer cells in vitro. In addition, L. casei extract has no synergistic effect on the inhibition of growth of cancer cells in the presence of anti-cancer drugs.

Side population in LX2 cells decreased by transforming growth factor-ß.

AIM: Side population (SP) cells are known to be enriched in stem/progenitor-like cells. Transforming growth factor (TGF)-ß signaling is associated with extracellular matrix (ECM) production in hepatic stellate cells. We hypothesized that the SP fraction in LX2 cells is associated with ECM deposition, which is regulated through TGF-ß signaling. METHODS: We investigated the relationship between SP cells and TGF-ß signaling in the hepatic stellate cell line LX2. The effects of TGF-ß and SB431542 on the SP fraction and expression of collagen type I and phospho-Smad2 was determined. RESULTS: We identified 0.8-3% SP cells in LX2 cells. The growth rate of sorted SP and non-SP cells was similar to that of the original LX2 population, but population of the G0/G1 phase was increased in SP cells. Treatment of LX2 cells with TGF-ß decreased the SP fraction in a dose-dependent manner and increased the production of collagen type I. Treatment of LX2 cells with SB431542 blocked the effect of TGF-ß on the SP fraction and the expression of collagen type I. We cultured LX2 cells on collagen-coated dishes to observe the effect of ECM deposition on the SP fraction. The growth rate and cell cycle distribution was similar to that observed on normal tissue culture dishes, but the SP fraction was decreased when LX2 cells were cultured on collagen-coated plates. CONCLUSION: These results show that LX2 cells contain an SP fraction and that TGF-ß signaling is involved in the induction of ECM deposition as well as the number of SP cells.

Hyperreflective photonic crystals created by shearing colloidal dispersions at ultrahigh volume fraction.

Colloidal crystallization serves as one of the most economic and scalable production methods for photonic crystals. However, insufficient optical performance, nonuniformity and low reproducibility remain challenges for advanced high-value applications. In this study, we optimally formulate a photocurable dispersion of silica particles and apply shear flow to unify the orientation of the colloidal crystals, ensuring high optical performance and uniformity. The silica particles experience strong repulsion at ultrahigh volume fractions of 50% but demonstrate low mobility, leading to polycrystalline structures. Applying shear flow to the dispersions allows the silica particles to rearrange into larger crystalline domains with a unidirectional orientation along the flow. This shear-induced structural change produces absolute reflectivity at the stopband as high as 90% and a high transparency of 90% at off-resonant wavelengths with minimal diffusive scattering. Furthermore, the strong interparticle repulsion ensures a uniform volume fraction of particles throughout the dispersion, reducing deviations in the optical properties. We intricately micropattern the photocurable dispersions using photolithography. Additionally, the photonic films and patterns can be stacked to form multiple layers, displaying mixed structural colors and multiple reflectance peaks without sacrificing reflectivity. These superior photonic materials hold promise for various optical applications, including optical components and anticounterfeiting patches.

Structural Color Inks Containing Photonic Microbeads for Direct Writing.

Printing structurally colored patterns is of great importance for providing customized graphics for various purposes. Although a direct writing technique has been developed, the use of colloidal dispersions as photonic inks requires delicate printing conditions and restricts the mechanical and optical properties of printed patterns. In this work, we produce elastic photonic microbeads through scalable bulk emulsification and formulate photonic inks containing microbeads for direct writing. To produce the microbeads, a photocurable colloidal dispersion is emulsified into a highly concentrated sucrose solution via vortexing, which results in spherical emulsion droplets with a relatively narrow size distribution. The microbeads are produced by photopolymerization and are then suspended in urethane acrylate resin at volume fractions of 0.35-0.45. The photonic inks retain high color saturation of the microbeads and offer enhanced printability and dimensional control on various target substrates including fabrics, papers, and even skins. Importantly, the printed graphics show high mechanical stability as the elastic microbeads are embedded in the polyurethane matrix. Moreover, the colors show a wide viewing angle and low-angle dependency due to the optical isotropy of individual microbeads and light refraction at the air-matrix interface. We postulate that this versatile direct writing technique is potentially useful for structural color coating and printing on the surfaces of arbitrary 3D objects.

Advanced Additive Manufacturing of Structurally-Colored Architectures.

Direct ink writing (DIW) stands out as a facile additive manufacturing method, minimizing material waste. Nonetheless, developing homogeneous Bingham inks with high yield stress and swift liquid-to-solid transitions for versatile 3D printing remains a challenge. In this study, high-performance Bingham inks are formulated by destabilizing silica particle suspensions in acrylate-based resin. A colloidal network forms in the shear-free state through interparticle attraction, achieved by disrupting the solvation layer of large resin molecules using polar molecules. The network is highly dense, with evenly distributed linkage strength as monodisperse particles undergo gelation at an ultra-high fraction. Crucially, the strength is calibrated to ensure a sufficiently large yield stress, while still allowing the network to reversibly melt under shear flow. The inks immediately undergo a liquid-to-solid transition upon discharge, while maintaining fluidity without nozzle clogging. The dense colloidal networks develop structural colors due to the short-range order. This enables the rapid and sophisticated drawing of structurally-colored 3D structures, relying solely on rheological properties. Moreover, the printed composite structures exhibit high mechanical stability due to the presence of the colloidal network, which expands the range of potential applications.

Evaluation of Human Platelet Lysate as an Alternative to Fetal Bovine Serum for Potential Clinical Applications of Stem Cells from Human Exfoliated Deciduous Teeth.

In recent years, there has been a surge in demand for and research focus on cell therapy, driven by the tissue-regenerative and disease-treating potentials of stem cells. Among the candidates, dental pulp stem cells (DPSCs) or human exfoliated deciduous teeth (SHED) have garnered significant attention due to their easy accessibility (non-invasive), multi-lineage differentiation capability (especially neurogenesis), and low immunogenicity. Utilizing these stem cells for clinical purposes requires careful culture techniques such as excluding animal-derived supplements. Human platelet lysate (hPL) has emerged as a safer alternative to fetal bovine serum (FBS) for cell culture. In our study, we assessed the impact of hPL as a growth factor supplement for culture medium, also conducting a characterization of SHED cultured in hPL-supplemented medium (hPL-SHED). The results showed that hPL has effects in enhancing cell proliferation and migration and increasing cell survivability in oxidative stress conditions induced by H2O2. The morphology of hPL-SHED exhibited reduced size and elongation, with a differentiation capacity comparable to or even exceeding that of SHED cultured in a medium supplemented with fetal bovine serum (FBS-SHED). Moreover, no evidence of chromosome abnormalities or tumor formation was detected. In conclusion, hPL-SHED emerges as a promising candidate for cell therapy, exhibiting considerable potential for clinical investigation.

Nanostructure-free crescent-shaped microparticles as full-color reflective pigments.

Structural colors provide a promising visualization with high color saturation, iridescent characteristics, and fade resistance. However, pragmatic uses are frequently impeded by complex manufacturing processes for sophisticated nanostructures. Here, we report a facile emulsion-templating strategy to produce crescent-shaped microparticles as structural color pigments. The micro-crescents exhibit brilliant colors under directional light originating from total internal reflections and optical interferences in the absence of periodic nanostructures while being transparent under ambient light. The colors are finely tunable by adjusting the size of the micro-crescents, which can be further mixed to enrich the variety. Importantly, the pre-defined convex surface secures high stability of colors and enables structural coloration on target surfaces through direct deposition as inks. We anticipate this class of nanostructure-free structural colorants is pragmatic as invisible inks in particular for anti-counterfeiting patches and color cosmetics with distinctive impressions due to low-cost, scalable manufacturing, unique optical properties, and versatility.

Growth inhibition by fusidic acid in cervical, thyroid, and breast carcinoma cell lines.

OBJECTIVE: We investigated the effects of fusidic acid (FA) on human cervical, thyroid, and breast carcinoma cell lines to determine the potential usefulness of FA in cancer treatment. METHODS: Six cancer cell lines (cervical cancer: Caski, HeLa; thyroid cancer: 8505C, TPC1; and breast cancer: MCF-7, MDA-MB-231) were treated with FA. Furthermore the changes in cell growth, cell cycle duration, and extent of apoptosis were analyzed. RESULTS: After FA treatment, the cancer cells showed a decrease in growth rate. In the cell death assay, the cell populations were similar in each cell type after treatment with FA, indicating that growth inhibition by FA was not related to the induction of apoptosis. FA induced cell cycle arrest at a dose that inhibited growth rate, which varied in different cell types. G0/G1 phase arrest occurs in breast cancer, S phase arrest in 8505C thyroid cancer, and G2/M phase arrest in cervical cancer. These results indicate that FA reduces growth rates by inducing cell cycle arrest. CONCLUSION: FA treatment can interfere with cell proliferation by inducing cell cycle arrest in human cervical, thyroid, and breast carcinoma cell lines. Thus, FA can be useful in treating human cervical, thyroid, and breast carcinomas.

Physicochemical, Biological, and Antibacterial Properties of Four Bioactive Calcium Silicate-Based Cements.

Calcium silicate-based cement (CSC) is a pharmaceutical agent that is widely used in dentistry. This bioactive material is used for vital pulp treatment due to its excellent biocompatibility, sealing ability, and antibacterial activity. Its drawbacks include a long setting time and poor maneuverability. Hence, the clinical properties of CSC have recently been improved to decrease its setting time. Despite the widespread clinical usage of CSC, there is no research comparing recently developed CSCs. Therefore, the purpose of this study is to compare the physicochemical, biological, and antibacterial properties of four commercial CSCs: two powder-liquid mix types (RetroMTA® [RETM]; Endocem® MTA Zr [ECZR]) and two premixed types (Well-Root™ PT [WRPT]; Endocem® MTA premixed [ECPR]). Each sample was prepared using circular Teflon molds, and tests were conducted after 24 h of setting. The premixed CSCs exhibited a more uniform and less rough surface, higher flowability, and lower film thickness than the powder-liquid mix CSCs. In the pH test, all CSCs showed values between 11.5 and 12.5. In the biological test, cells exposed to ECZR at a concentration of 25% showed greater cell viability, but none of the samples showed a significant difference at low concentration (p > 0.05). Alkaline phosphatase staining revealed that cells exposed to ECZR underwent more odontoblast differentiation than the cells exposed to the other materials; however, no significant difference was observed at a concentration of 12.5% (p > 0.05). In the antibacterial test, the premixed CSCs showed better results than the powder-liquid mix CSCs, and ECPR yielded the best results, followed by WRPT. In conclusion, the premixed CSCs showed improved physical properties, and of the premixed types, ECPR exhibited the highest antibacterial properties. For biological properties, none of these materials showed significant differences at 12.5% dilution. Therefore, ECPR may be a promising material with high antibacterial activity among the four CSCs, but further investigation is needed for clinical situations.

Physicochemical, Pre-Clinical, and Biological Evaluation of Viscosity Optimized Sodium Iodide-Incorporated Paste.

This study aimed to investigate the impact of different viscosities of silicone oil on the physicochemical, pre-clinical usability, and biological properties of a sodium iodide paste. Six different paste groups were created by mixing therapeutic molecules, sodium iodide (D30) and iodoform (I30), with calcium hydroxide and one of the three different viscosities of silicone oil (high (H), medium (M), and low (L)). The study evaluated the performance of these groups, including I30H, I30M, I30L, D30H, D30M, and D30L, using multiple parameters such as flow, film thickness, pH, viscosity, and injectability, with statistical analysis (p < 0.05). Remarkably, the D30L group demonstrated superior outcomes compared to the conventional iodoform counterpart, including a significant reduction in osteoclast formation, as examined through TRAP, c-FOS, NFATc1, and Cathepsin K (p < 0.05). Additionally, mRNA sequencing showed that the I30L group exhibited increased expression of inflammatory genes with upregulated cytokines compared to the D30L group. These findings suggest that the optimized viscosity of the sodium iodide paste (D30L) may lead to clinically favorable outcomes, such as slower root resorption, when used in primary teeth. Overall, the results of this study suggest that the D30L group shows the most satisfactory outcomes, which may be a promising root-filling material that could replace conventional iodoform-based pastes.

Berberine-induced growth inhibition of epithelial ovarian carcinoma cell lines.

AIM: The aim of this study is to analyze the impact of berberine on the two human epithelial ovarian carcinoma cell lines OVCAR-3 and SKOV-3 in relation to the potential usefulness of berberine in the treatment of epithelial ovarian cancer. METHODS: Under adherent culture conditions, the cell lines were treated with berberine and analyzed for changes in cell growth. The cell cycle duration and degree of apoptosis were evaluated by means of propidium iodide staining and Annexin V staining. RESULTS: After the berberine treatment, the two cell lines showed a dose-dependent reduction in the growth rate. In the cell cycle analysis, the OVCAR-3 and SKOV-3 cells showed an increased DNA content of 5% in the G2/M phase and 7% in the S phase, respectively. Additionally, the results confirm the cell cycle arrest by immunoblotting and the up-regulation of p27; however, in the apoptosis analysis, neither cell line showed an increase in apoptosis after the berberine treatment. CONCLUSION: Berberine treatment can inhibit proliferation through a cell cycle arrest in OVCAR-3 and SKOV-3 cells. Thus, berberine may be a novel anticancer drug for the treatment of ovarian cancer.

Investigating the Effects of Conditioned Media from Stem Cells of Human Exfoliated Deciduous Teeth on Dental Pulp Stem Cells.

Pulp regeneration has recently attracted interest in modern dentistry. However, the success ratio of pulp regeneration is low due to the compromising potential of stem cells, such as their survival, migration, and odontoblastic differentiation. Stem cells from human exfoliated deciduous teeth (SHED) have been considered a promising tool for regenerative therapy due to their ability to secrete multiple factors that are essential for tissue regeneration, which is achieved by minimally invasive procedures with fewer ethical or legal concerns than those of other procedures. The aim of this study is to investigate the potency of SHED-derived conditioned media (SHED CM) on dental pulp stem cells (DPSCs), a major type of mesenchymal stem cells for dental pulp regeneration. Our results show the promotive efficiency of SHED CM on the proliferation, survival rate, and migration of DPSCs in a dose-dependent manner. Upregulation of odontoblast/osteogenic-related marker genes, such as ALP, DSPP, DMP1, OCN, and RUNX2, and enhanced mineral deposition of impaired DPSCs are also observed in the presence of SHED CM. The analysis of SHED CM found that a variety of cytokines and growth factors have positive effects on cell proliferation, migration, anti-apoptosis, and odontoblast/osteogenic differentiation. These findings suggest that SHED CM could provide some benefits to DPSCs in pulp regeneration.

The Potential Application of Human Gingival Fibroblast-Conditioned Media in Pulp Regeneration: An In Vitro Study.

Regenerative endodontic treatment based on tissue engineering has recently gained interest in contemporary restorative dentistry. However, low survival rates and poor potential differentiation of stem cells could undermine the success rate of pulp regenerative therapy. Human gingival fibroblast-conditioned medium (hGF-CM) has been considered a potential therapy for tissue regeneration due to its stability in maintaining multiple factors essential for tissue regeneration compared to live cell transplantation. This study aimed to investigate the potency of hGF-CM on stem cells from human dental pulp (DPSC) in pulp regeneration. A series of experiments confirmed that hGF-CM contributes to a significant increase in proliferation, migration capability, and cell viability of DPSC after H2O2 exposure. Moreover, it has been proved to facilitate the odontogenic differentiation of DPSC via qRT-PCR, ALP (alkaline phosphatase), and ARS (Alizarin Red S) staining. It has been discovered that such highly upregulated odontogenesis is related to certain types of ECM proteins (collagen and laminin) from hGF-CM via proteomics. In addition, it is found that the ERK pathway is a key mechanism via inhibition assay based on RNA-seq result. These findings demonstrate that hGF-CM could be beneficial biomolecules for pulp regeneration.