Hypoxic dental pulp stem cells-released succinate promotes osteoclastogenesis and root resorption.

Introduction: Clinical studies have shown that endodontically-treated nonvital teeth exhibit less root resorption during orthodontic tooth movement. The purpose of this study was to explore whether hypoxic dental pulp stem cells (DPSCs) can promote osteoclastogenesis in orthodontically induced inflammatory root resorption (OIIRR). Methods: Succinate in the supernatant of DPSCs under normal and hypoxic conditions was measured by a succinic acid assay kit. The culture supernatant of hypoxia-treated DPSCs was used as conditioned medium (Hypo-CM). Bone marrow-derived macrophages (BMDMs) from succinate receptor 1 (SUCNR1)-knockout or wild-type mice were cultured with conditioned medium (CM), exogenous succinate or a specific inhibitor of SUCNR1 (4c). Tartrate-resistant acid phosphatase (TRAP) staining, Transwell assays, qPCR, Western blotting, and resorption assays were used to evaluate osteoclastogenesis-related changes. Results: The concentration of succinate reached a maximal concentration at 6 h in the supernatant of hypoxia-treated DPSCs. Hypo-CM-treated macrophages were polarized to M1 proinflammatory macrophages. Hypo-CM treatment significantly increased the formation and differentiation of osteoclasts and increased the expression of osteoclastogenesis-related genes, and this effect was inhibited by the specific succinate inhibitor 4c. Succinate promoted chemotaxis and polarization of M1-type macrophages with increased expression of osteoclast generation-related genes. SUCNR1 knockout decreased macrophage migration, M1 macrophage polarization, differentiation and maturation of osteoclasts, as shown by TRAP and NFATc1 expression and cementum resorption. Conclusions: Hypoxic DPSC-derived succinate may promote osteoclast differentiation and root resorption. The regulation of the succinate-SUCNR1 axis may contribute to the reduction in the OIIRR.

4-META/MMA-TBB resin containing nano hydroxyapatite induces the healing of periodontal tissue repair in perforations at the pulp chamber floor.

We aimed to evaluate the materials based on 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate tri-n-butylborane (Super-bond [SB]) and nano hydroxyapatite (naHAp) for the repair of perforation at pulp chamber floor (PPF) in vitro and in vivo models. SB and naHAp were mixed in the mass ratio of 10% or 30% to produce naHAp/SB. Human periodontal ligament stem cells (HPDLSCs) were cultured on resin discs of SB or naHAp/SB to analyze the effects of naHAp/SB on cell adhesion, proliferation, and cementoblastic differentiation. A rat PPF model was treated with SB or naHAp/SB to examine the effects of naHAp/SB on the healing of defected cementum and periodontal ligament (PDL) at the site of PPF. HPDLSCs were spindle-shaped and adhered to all resin discs. Changing the resin from SB to naHAp/SB did not significantly alter cell proliferation. Both 10% and 30% naHAp/SB were more effective than SB in promoting cementoblastic differentiation of HPDLSCs. In the rat PPF model, 30% naHAp/SB was more effective than SB in promoting the formation Sharpey's fiber-like structures with expression of the PDL-related marker and cementum-like structures with expression of cementum-related markers. In conclusion, 30% naHAp/SB can be the new restorative material for PPF because it exhibited the abilities of adhering to dentin and healing of defected periodontal tissue.

The Effect of Glycyrrhizin on the Viability and Proliferation of Dental Pulp Stem Cells Compared to Intracanal Medicaments.

AIM: To study the effect of glycyrrhizin (GA) on the viability and proliferation of dental pulp stem cells (DPSCs) compared with intracanal medicaments. MATERIALS AND METHODS: Third molars of an adult donor were used to obtain the DPSCs. Flow cytometry was utilized to conduct phenotypic analysis for DPSCs. The methyl-thiazol tetrazolium (MTT) test was used to detect the cell viability. Cell proliferation assay was conducted at distinct time intervals: 3, 5, and 7 days. RESULTS: The flow cytometry analysis verified the positive expression of mesenchymal cell surface antigen molecules (CD73, CD90, and CD105) and the absence of hematological markers (CD14, CD34, and CD45) in the DPSCs. The cells that treated with concentrations more than 0.5 mg/mL of Ca(OH2) and triple antibiotic paste (TAP) gave significant decrease in viability in comparison to the untreated cells (p < 0.05). Also, the cells treated with concentrations 50 and 25 µM of GA showed no significant difference compared with the untreated cells (p > 0.05), while concentrations 12.5 and 6.25 µM expressed a significant increase in viability compared with the untreated cells (p < 0.05). At 7 days, cells treated with the three different concentrations of GA (12.5, 25, and 50 µM) demonstrated a significant increase in cell density compared with Ca(OH)2 and TAP-treated cells (p < 0.05). CONCLUSION: Based upon the potential of GA on DPSCs proliferation compared with Ca(OH)2 and TAP, It is conceivable to acknowledge that GA could be used as an intracanal medicaments for revascularization process of necrotic immature teeth. CLINICAL SIGNIFICANCE: This study emphasizes the significance of assessing alternative root canal medicaments and their impact on the proliferation and viability of DPSCs. The results regarding GA, specifically its impact on the viability and growth of DPSCs, provide essential understanding for its potential application as an intracanal medicine. This study adds to the continuous endeavors in identifying safer and more efficient intracanal therapies, which are essential for improving patient outcomes in endodontic operations. How to cite this article: Alrashidi MA, Badawi MF, Elbeltagy MG, et al. The Effect of Glycyrrhizin on the Viability and Proliferation of Dental Pulp Stem Cells Compared to Intracanal Medicaments. J Contemp Dent Pract 2024;25(3):267-275.

Effect of Helichrysum italicum in Promoting Collagen Deposition and Skin Regeneration in a New Dynamic Model of Skin Wound Healing.

Natural products have many healing effects on the skin with minimal or no adverse effects. In this study, we analyzed the regenerative properties of a waste product (hydrolate) derived from Helichrysum italicum (HH) on scratch-tested skin cell populations seeded on a fluidic culture system. Helichrysum italicum has always been recognized in the traditional medicine of Mediterranean countries for its wide pharmacological activities. We recreated skin physiology with a bioreactor that mimics skin stem cell (SSCs) and fibroblast (HFF1) communication as in vivo skin layers. Dynamic culture models represent an essential instrument for recreating and preserving the complex multicellular organization and interactions of the cellular microenvironment. Both cell types were exposed to two different concentrations of HH after the scratch assay and were compared to untreated control cells. Collagen is the constituent of many wound care products that act directly on the damaged wound environment. We analyzed the role played by HH in stimulating collagen production during tissue repair, both in static and dynamic culture conditions, by a confocal microscopic analysis. In addition, we performed a gene expression analysis that revealed the activation of a molecular program of stemness in treated skin stem cells. Altogether, our results indicate a future translational application of this natural extract to support skin regeneration and define a new protocol to recreate a dynamic process of healing.

Modeling alcohol-associated liver disease in humans using adipose stromal or stem cell-derived organoids.

Alcohol-associated liver disease (ALD) is a prevalent liver disease, yet research is hampered by the lack of suitable and reliable human ALD models. Herein, we generated human adipose stromal/stem cell (hASC)-derived hepatocellular organoids (hAHOs) and hASC-derived liver organoids (hALOs) in a three-dimensional system using hASC-derived hepatocyte-like cells and endodermal progenitor cells, respectively. The hAHOs were composed of major hepatocytes and cholangiocytes. The hALOs contained hepatocytes and nonparenchymal cells and possessed a more mature liver function than hAHOs. Upon ethanol treatment, both steatosis and inflammation were present in hAHOs and hALOs. The incubation of hALOs with ethanol resulted in increases in the levels of oxidative stress, the endoplasmic reticulum protein thioredoxin domain-containing protein 5 (TXNDC5), the alcohol-metabolizing enzymes ADH1B and ALDH1B1, and extracellular matrix accumulation, similar to those of liver tissues from patients with ALD. These results present a useful approach for understanding the pathogenesis of ALD in humans, thus facilitating the discovery of effective treatments.

The Influence of Tacrolimus on Cellular Morphology, Cellular Viability, Osteogenic Differentiation, and mRNA Expression within Stem Cell Spheroids.

Background and Objectives: Tacrolimus is a macrolide lactone compound derived from the bacterium Streptomyces tsukubensis, widely known as an immunosuppressant. In basic research, the effects of tacrolimus on osteogenic differentiation have been tested using mesenchymal stem cells. In this study, tacrolimus's effects on the cellular survival and osteogenic differentiation of stem cell spheroids were investigated. Materials and Methods: Concave microwells were used to form stem cell spheroids in the presence of tacrolimus at final concentrations of 0 µg/mL, 0.1 µg/mL, 1 µg/mL, 10 µg/mL, and 100 µg/mL. A microscope was used to test cellular vitality qualitatively, and an assay kit based on water-soluble tetrazolium salt was used to measure cellular viability quantitatively. Alkaline phosphatase activity and an anthraquinone dye test for measuring calcium deposits were used to assess osteogenic differentiation. To assess the expression of osteogenic differentiation, a quantitative polymerase chain reaction, Western blot, and RNA sequencing were performed. Results: Spheroids across all concentrations maintained a relatively uniform and spherical shape. Cell viability assay indicated that tacrolimus, up to a concentration of 100 µg/mL, did not significantly impair cell viability within spheroids cultured in osteogenic media. The increase in calcium deposition, particularly at lower concentrations of tacrolimus, points toward an enhancement in osteogenic differentiation. There was an increase in COL1A1 expression across all tacrolimus concentrations, as evidenced by the elevated mean and median values, which may indicate enhanced osteogenic activity. Conclusions: This study showed that tacrolimus does not significantly impact the viability of stem cell spheroids in osteogenic media, even at high concentrations. It also suggests that tacrolimus may enhance osteogenic differentiation, as indicated by increased calcium deposition and COL1A1 expression. These findings advance our understanding of tacrolimus's potential roles in tissue repair, regeneration, and stem cell-based therapeutic applications.

Effects of Ibuprofen and Diclofenac Pre-Treatment on Viability and Apoptosis Processes in Human Dental Pulp Stem Cells.

Background and Objectives: Stem cell-based regeneration strategies have shown therapeutic efficacy in various fields of regenerative medicine. These include bone healing after bone augmentation, often complicated by pain, which is managed by using nonsteroidal anti-inflammatory drugs (NSAIDs). However, information is limited about how NSAIDs affect the therapeutic potential of stem cells. Materials and Methods: We investigated the effects of ibuprofen and diclofenac on the characteristics, morphology, and immunophenotype of human mesenchymal stromal cells isolated from the dental pulp (DPSCs) and cultured in vitro, as well as their effects on the expression of angiogenic growth factors (VEGFA and HGF) and selected genes in apoptosis signalling pathways (BAX, BAK, CASP3, CASP9, and BCL2). Results: Ibuprofen and diclofenac significantly reduced the viability of DPSCs, while the expression of mesenchymal stem cell surface markers was unaffected. Both ibuprofen and diclofenac treatment significantly upregulated the expression of HGF, while the expression of VEGFA remained unchanged. Ibuprofen significantly altered the expression of several apoptosis-related genes, including the upregulation of CASP9 and BCL2, with decreased CASP3 expression. BAK, CASP3, CASP9, and BCL2 expressions were significantly increased in the diclofenac-treated DPSCs, while no difference was demonstrated in BAX expression. Conclusions: Our results suggest that concomitant use of the NSAIDs ibuprofen or diclofenac with stem cell therapy may negatively impact cell viability and alter the expression of apoptosis-related genes, affecting the efficacy of stem cell therapy.

Anaesthetics reduce the viability of adipose-derived stem cells.

Adipose-derived stem cells (ADSCs) are characterized by their low immunogenicity and unique immunosuppressive properties, providing many opportunities for autologous transplantation in regenerative medicine and plastic surgery. These methods are characterized by low rejection rates and intense stimulation of tissue regeneration. However, procedures during which fat tissue is harvested occur under local anaesthesia. To better understand the effects and mechanisms of anaesthetic compounds in cosmetic and therapeutic procedures, the present study used a mixture of these compounds (0.1% epinephrine, 8.4% sodium bicarbonate, and 4% articaine) and examined their impact on a human adipose-derived stem cell line. The results showed anesthetics' negative, dose-dependent effect on cell viability and proliferation, especially during the first 24 h of incubation. After extending the exposure to 48 and 72 h of incubation, cells adapted to new culture conditions. In contrast, no significant changes were observed in immunophenotype, cell cycle progression, and apoptosis. The results obtained from this study provide information on the effect of the selected mixture of anaesthetics on the characteristics and function of ASC52telo cells. The undesirable changes in the metabolic activity of cells suggest the need to search for new drugs to harvest cells with unaltered properties and higher efficacy in aesthetic medicine treatments.

Exosomes derived from adipose tissue-derived stem cells alleviated H2O2-induced oxidative stress and endothelial-to-mesenchymal transition in human umbilical vein endothelial cells by inhibition of the mir-486-3p/Sirt6/Smad signaling pathway.

Hypertrophic scar (HS) is characterized by excessive collagen deposition and myofibroblasts activation. Endothelial-to-mesenchymal transition (EndoMT) and oxidative stress were pivotal in skin fibrosis process. Exosomes derived from adipose tissue-derived stem cells (ADSC-Exo) have the potential to attenuate EndoMT and inhibit fibrosis. The study revealed reactive oxygen species (ROS) levels were increased during EndoMT occurrence of dermal vasculature of HS. The morphology of endothelial cells exposure to H2O2, serving as an in vitro model of oxidative stress damage, transitioned from a cobblestone-like appearance to a spindle-like shape. Additionally, the levels of endothelial markers decreased in H2O2-treated endothelial cell, while the expression of fibrotic markers increased. Furthermore, H2O2 facilitated the accumulation of ROS, inhibited cell proliferation, retarded its migration and suppressed tube formation in endothelial cell. However, ADSC-Exo counteracted the biological effects induced by H2O2. Subsequently, miRNAs sequencing analysis revealed the significance of mir-486-3p in endothelial cell exposed to H2O2 and ADSC-Exo. Mir-486-3p overexpression enhanced the acceleration of EndoMT, its inhibitors represented the attenuation of EndoMT. Meanwhile, the target regulatory relationship was observed between mir-486-3p and Sirt6, whereby Sirt6 exerted its anti-EndoMT effect through Smad2/3 signaling pathway. Besides, our research had successfully demonstrated the impact of ADSC-Exo and mir-486-3p on animal models. These findings of our study collectively elucidated that ADSC-Exo effectively alleviated H2O2-induced ROS and EndoMT by inhibiting the mir-486-3p/Sirt6/Smad axis.

Evaluation of dental pulp stem cells response to flowable nano-hybrid dental composites: A comparative analysis.

BACKGROUND: Flowable resin composites (FRC) are tooth-colored restorative materials that contain a lower filler particle content, and lower viscosity than their bulk counterparts, making them useful for specific clinical applications. Yet, their chemical makeup may impact the cellular population of the tooth pulp. This in-vitro study assessed the cytocompatibility and odontogenic differentiation capacity of dental pulp stem cells (DPSCs) in response to two recent FRC material extracts. METHODS: Extracts of the FRC Aura easyflow (AEF) and Polofil NHT Flow (PNF) were applied to DPSCs isolated from extracted human teeth. Cell viability of DPSCs was assessed using MTT assay on days 1, 3 and 7. Cell migration was assessed using the wound healing assay. DPSCs' capacity for osteo/odontogenic differentiation was assessed by measuring the degree of mineralization by Alizarin Red S staining, alkaline phosphatase enzyme (ALP) activity, and monitoring the expression of osteoprotegerin (OPG), RUNX Family Transcription Factor 2 (RUNX2), and the odontogenic marker dentin sialophosphoprotein (DSPP) by RT-PCR. Monomer release from the FRC was also assessed by High-performance liquid chromatography analysis (HPLC). RESULTS: DPSCs exposed to PNF extracts showed significantly higher cell viability, faster wound closure, and superior odontogenic differentiation. This was apparent through Alizarin Red staining of calcified nodules, elevated alkaline phosphatase activity, and increased expression of osteo/odontogenic markers. Moreover, HPLC analysis revealed a higher release of TEDGMA, UDMA, and BISGMA from AEF. CONCLUSIONS: PNF showed better cytocompatibility and enhancement of odontogenic differentiation than AEF.

Cytosine Deaminase-Overexpressing hTERT-Immortalized Human Adipose Stem Cells Enhance the Inhibitory Effects of Fluorocytosine on Tumor Growth in Castration Resistant Prostate Cancer.

A promising de novo approach for the treatment of Castration-resistant prostate cancer (CRPC) exploits cell-mediated enzyme prodrug therapy comprising cytosine deaminase (CD) and fluorouracil (5-FC). The aim of this study was to determine the potential of bacterial CD-overexpressing hTERT-immortalized human adipose stem cells (hTERT-ADSC.CD) to suppress CRPC. A lentiviral vector encoding a bacterial CD gene was used to transfect and to generate the hTERT-ADSC.CD line. The ability of the cells to migrate selectively towards malignant cells was investigated in vitro. PC3 and hTERT-ADSC.CD cells were co-cultured. hTERT-ADSC.CD and 1 × 106 PC3 cells were administered to nude mice via intracardiac and subcutaneous injections, respectively, and 5-FC was given for 14 days. hTERT-ADSC.CD were successfully engineered. Enhanced in vitro hTERT-ADSC.CD cytotoxicity and suicide effect were evident following administration of 5 µM 5-FC. hTERT-ADSC.CD, together with 5-FC, augmented the numbers of PC3 cells undergoing apoptosis. In comparison to controls administered hTERT-ADSC.CD monotherapy, hTERT-ADSC.CD in combination with 5-FC demonstrated a greater suppressive effect on tumor. In CPRC-bearing mice, tumor suppression was enhanced by the combination of CD-overexpressing ADSC and the prodrug 5-FC. Stem cells exhibiting CD gene expression are a potential novel approach to treatment for CRPC.

Functional extracellular vesicles from SHEDs combined with gelatin methacryloyl promote the odontogenic differentiation of DPSCs for pulp regeneration.

BACKGROUND: Pulp regeneration is a novel approach for the treatment of immature permanent teeth with pulp necrosis. This technique includes the combination of stem cells, scaffolds, and growth factors. Recently, stem cell-derived extracellular vesicles (EVs) have emerged as a new methodology for pulp regeneration. Emerging evidence has proven that preconditioning is an effective scheme to modify EVs for better therapeutic potency. Meanwhile, proper scaffolding is of great significance to protect EVs from rapid clearance and destruction. This investigation aims to fabricate an injectable hydrogel loaded with EVs from pre-differentiated stem cells from human exfoliated deciduous teeth (SHEDs) and examine their effects on pulp regeneration. RESULTS: We successfully employed the odontogenic induction medium (OM) of SHEDs to generate functional EV (OM-EV). The OM-EV at a concentration of 20 µg/mL was demonstrated to promote the proliferation and migration of dental pulp stem cells (DPSCs). The results revealed that OM-EV has a better potential to promote odontogenic differentiation of DPSCs than common EVs (CM-EV) in vitro through Alizarin red phalloidin, alkaline phosphatase staining, and assessment of the expression of odontogenic-related markers. High-throughput sequencing suggests that the superior effects of OM-EV may be attributed to activation of the AMPK/mTOR pathway. Simultaneously, we prepared a photocrosslinkable gelatin methacryloyl (GelMA) to construct an OM-EV-encapsulated hydrogel. The hydrogel exhibited sustained release of OM-EV and good biocompatibility for DPSCs. The released OM-EV from the hydrogel could be internalized by DPSCs, thereby enhancing their survival and migration. In tooth root slices that were subcutaneously transplanted in nude mice, the OM-EV-encapsulated hydrogel was found to facilitate dentinogenesis. After 8 weeks, there was more formation of mineralized tissue, as well as higher levels of dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1). CONCLUSIONS: The effects of EV can be substantially enhanced by preconditioning of SHEDs. The functional EVs from SHEDs combined with GelMA are capable of effectively promoting dentinogenesis through upregulating the odontogenic differentiation of DPSCs, which provides a promising therapeutic approach for pulp regeneration.

Inhibition of lipopolysaccharide-induced NF-κB maintains osteogenesis of dental pulp and periodontal ligament stem cells.

Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs) can differentiate into osteoblasts, indicating that both are potential candidates for bone tissue engineering. Osteogenesis is influenced by many environmental factors, one of which is lipopolysaccharide (LPS). LPS-induced NF-κB activity affects the osteogenic potencies of different types of MSCs differently. This study evaluated the effect of LPS-induced NF-κB activity and its inhibition in DPSCs and PDLSCs. DPSCs and PDLSCs were cultured in an osteogenic medium, pretreated with/without NF-κB inhibitor Bay 11-7082, and treated with/without LPS. Alizarin red staining was performed to assess bone nodule formation, which was observed under an inverted light microscope. NF-κB and alkaline phosphatase (ALP) activities were measured to examine the effect of Bay 11-7082 pretreatment and LPS supplementation on osteogenic differentiation of DPSCs and PDLSCs. LPS significantly induced NF-κB activity (p = 0.000) and reduced ALP activity (p = 0.000), which inhibited bone nodule formation in DPSCs and PDLSCs. Bay 11-7082 inhibited LPS-induced NF-κB activity, and partially maintained ALP activity and osteogenic potency of LPS-supplemented DPSCs and PDLSCs. Thus, inhibition of LPS-induced NF-κB activity can maintain the osteogenic potency of DPSCs and PDLSCs.

GNAI3 mediated by Lin28A regulates lipopolysaccharide-induced inflammation and osteogenic differentiation in periodontal stem cells by mediating the NF-κB/NLRP3 inflammasome pathway.

OBJECTIVES: The aim of this study was to investigate the regulatory role of G protein subunit alpha i3 (GNAI3) in periodontitis. DESIGN: Following the induction of human periodontal ligament stem cells (hPDLSCs) with lipopolysaccharide (LPS), the mRNA and protein expressions of GNAI3 and Lin28A were detected by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot. The transfection efficiency of Oe-GNAI3 and sh-Lin28A was examined by virtue of RT-qPCR and western blot. With the application of ELISA and flow cytometry, the releases of inflammatory cytokines and cell apoptosis were appraised. Alkaline phosphatase (ALP) staining and alizarin red S (ARS) staining were conducted to evaluate osteogenic differentiation. Next, the binding ability of Lin28A with GNAI3 mRNA was estimated by radioimmunoprecipitation (RIP) assay while the stability of GNAI3 mRNA was assessed utilizing RT-qPCR. Western blot was employed for the measurement of inflammation-, apoptosis- and nuclear factor-kappaB (NF-κB)/NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway-related proteins and osteogenic markers. RESULTS: The expression of GNAI3 was down-regulated in LPS-induced hPDLSCs. After the transfection with Oe-GNAI3, the inflammation and apoptosis in LPS-induced hPDLSCs were inhibited while osteogenic differentiation was promoted. Moreover, Lin28A could stabilize GNAI3 mRNA and Lin28A knockdown significantly reduced GNAI3 expression. Further experiments verified that the inhibitory effects of GNAI3 overexpression on LPS-induced cellular inflammation and cell apoptosis as well as the promotive effects on osteogenic differentiation in hPDLSCs were all partially counteracted by Lin28A depletion, which may possibly be mediated via the regulation of the NF-κB/NLRP3 inflammasome pathway. CONCLUSION: GNAI3 that mediated by Lin28A regulates the inflammation and osteogenic differentiation in LPS-induced hPDLSCs by mediating the NF-κB/NLRP3 inflammasome pathway.

Malvidin attenuates trauma-induced heterotopic ossification of tendon in rats by targeting Rheb for degradation via the ubiquitin-proteasome pathway.

The pathogenesis of trauma-induced heterotopic ossification (HO) in the tendon remains unclear, posing a challenging hurdle in treatment. Recognizing inflammation as the root cause of HO, anti-inflammatory agents hold promise for its management. Malvidin (MA), possessing anti-inflammatory properties, emerges as a potential agent to impede HO progression. This study aimed to investigate the effect of MA in treating trauma-induced HO and unravel its underlying mechanisms. Herein, the effectiveness of MA in preventing HO formation was assessed through local injection in a rat model. The potential mechanism underlying MA's treatment was investigated in the tendon-resident progenitor cells of tendon-derived stem cells (TDSCs), exploring its pathway in HO formation. The findings demonstrated that MA effectively hindered the osteogenic differentiation of TDSCs by inhibiting the mTORC1 signalling pathway, consequently impeding the progression of trauma-induced HO of Achilles tendon in rats. Specifically, MA facilitated the degradation of Rheb through the K48-linked ubiquitination-proteasome pathway by modulating USP4 and intercepted the interaction between Rheb and the mTORC1 complex, thus inhibiting the mTORC1 signalling pathway. Hence, MA presents itself as a promising candidate for treating trauma-induced HO in the Achilles tendon, acting by targeting Rheb for degradation through the ubiquitin-proteasome pathway.

Enhanced Vascular-like Network Formation of Encapsulated HUVECs and ADSCs Coculture in Growth Factors Conjugated GelMA Hydrogels.

Tissue engineering primarily aimed to alleviate the insufficiency of organ donations worldwide. Nonetheless, the survival of the engineered tissue is often compromised due to the complexity of the natural organ architectures, especially the vascular system inside the organ, which allows food-waste transfer. Thus, vascularization within the engineered tissue is of paramount importance. A critical aspect of this endeavor is the ability to replicate the intricacies of the extracellular matrix and promote the formation of functional vascular networks within engineered constructs. In this study, human adipose-derived stem cells (hADSCs) and human umbilical vein endothelial cells (HUVECs) were cocultured in different types of gelatin methacrylate (GelMA). In brief, pro-angiogenic signaling growth factors (GFs), vascular endothelial growth factor (VEGF165) and basic fibroblast growth factor (bFGF), were conjugated onto GelMA via an EDC/NHS coupling reaction. The GelMA hydrogels conjugated with VEGF165 (GelMA@VEGF165) and bFGF (GelMA@bFGF) showed marginal changes in the chemical and physical characteristics of the GelMA hydrogels. Moreover, the conjugation of these growth factors demonstrated improved cell viability and cell proliferation within the hydrogel construct. Additionally, vascular-like network formation was observed predominantly on GelMA@GrowthFactor (GelMA@GF) hydrogels, particularly on GelMA@bFGF. This study suggests that growth factor-conjugated GelMA hydrogels would be a promising biomaterial for 3D vascular tissue engineering.

Cell viability assessment and ion release profiles of GICs modified with TiO2- and Mg-doped hydroxyapatite nanoparticles.

OBJECTIVES: To assess and compare the cell viability and ion release profiles of two conventional glass ionomer cements (GICs), Fuji IX and Ketac Molar EasyMix, modified with TiO2 and Mg-doped-HAp nanoparticles (NPs). METHODS: TiO2 NPs, synthesized via a sol-gel method, and Mg-doped hydroxyapatite, synthesized via a hydrothermal process, were incorporated into GICs at a concentration of 5 wt.%. The biocompatibility of prepared materials was assessed by evaluating their effects on the viability of dental pulp stem cells (DPSCs), together with monitoring ion release profiles. Statistical analysis was performed using One-way analysis of variance, with significance level p < 0.05. RESULTS: The addition of NPs did not significantly affect the biocompatibility of GICs, as evidenced by comparable decreased levels in cell viability to their original formulations. Distinct variations in cell viability were observed among Fuji IX and Ketac Molar, including their respective modifications. FUJI IX and its modification with TiO2 exhibited moderate decrease in cell viability, while other groups exhibited severe negative effects. While slight differences in ion release profiles were observed among the groups, significant variations compared to original cements were not achieved. Fluoride release exhibited an initial "burst release" within the initial 24 h in all samples, stabilizing over subsequent days. CONCLUSIONS: The addition of NPs did not compromise biocompatibility, nor anticariogenic potential of tested GICs. However, observed differences among FUJI IX and Ketac Molar, including their respective modifications, as well as induced low viability of DPSC by all tested groups, suggest the need for careful consideration of cement composition in their biological assessments. CLINICAL SIGNIFICANCE: The findings contribute to understanding the complex interaction between NPs and GIC matrices. However, the results should be interpreted recognizing the inherent limitations associated with in vitro studies. Further research avenues could explore long-term effects, in vivo performance, and potential clinical applications.

Progenitor Cell Function and Cardiovascular Remodelling Induced by SGLT2 Inhibitors.

Sodium-glucose cotransporters 2 (SGLT2) are high-capacity, low-affinity transporters, expressed mainly in the early portion of the proximal renal tube, mediating up to 90% of renal glucose uptake, while SGLT1 receptors are found mainly in the small intestine, facilitating glucose absorption. SGLT2 inhibitors (SGLT2i) originally emerged as agents for the treatment of type 2 diabetes mellitus; however, they soon demonstrated remarkable cardio- and renoprotective actions that led to their licensed use for the treatment of heart failure and chronic kidney disease, regardless of the diabetic status. Cardiovascular remodelling represents an umbrella term that encompasses changes that occur in the cardiovascular system, from the molecular and cellular level, to tissue and organs after local injury, chronic stress, or pressure. SGLT modulation has been shown to positively affect many of these molecular and cellular changes observed during pathological remodelling. Among the different pathophysiological mechanisms that contribute to adverse remodelling, various stem and progenitor cells have been shown to be involved, through alterations in their number or function. Recent studies have examined the effects of SGLT2i on stem and progenitor cell populations and more specifically on endothelial progenitor cells (EPCs). Although some found no significant effect, others showed that SGLT2i can modulate the morphology and function of EPCs. These preliminary observations of the effect of SGLT2i on EPCs may be responsible for some of the beneficial effects of gliflozins on pathological remodelling and, by extension, on cardiovascular disease. The purpose of this narrative review is to critically discuss recent evidence on the cardioprotective effects of SGLT2is, in the context of cardiac remodelling.

Roxithromycin exposure induces motoneuron malformation and behavioral deficits of zebrafish by interfering with the differentiation of motor neuron progenitor cells.

Roxithromycin (ROX), a commonly used macrolide antibiotic, is extensively employed in human medicine and livestock industries. Due to its structural stability and resistance to biological degradation, ROX persists as a resilient environmental contaminant, detectable in aquatic ecosystems and food products. However, our understanding of the potential health risks to humans from continuous ROX exposure remains limited. In this study, we used the zebrafish as a vertebrate model to explore the potential developmental toxicity of early ROX exposure, particularly focusing on its effects on locomotor functionality and CaP motoneuron development. Early exposure to ROX induces marked developmental toxicity in zebrafish embryos, significantly reducing hatching rates (n=100), body lengths (n=100), and increased malformation rates (n=100). The zebrafish embryos treated with a corresponding volume of DMSO (0.1%, v/v) served as vehicle controls (veh). Moreover, ROX exposure adversely affected the locomotive capacity of zebrafish embryos, and observations in transgenic zebrafish Tg(hb9:eGFP) revealed axonal loss in motor neurons, evident through reduced or irregular axonal lengths (n=80). Concurrently, abnormal apoptosis in ROX-exposed zebrafish embryos intensified alongside the upregulation of apoptosis-related genes (bax, bcl2, caspase-3a). Single-cell sequencing further disclosed substantial effects of ROX on genes involved in the differentiation of motor neuron progenitor cells (ngn1, olig2), axon development (cd82a, mbpa, plp1b, sema5a), and neuroimmunity (aplnrb, aplnra) in zebrafish larvae (n=30). Furthermore, the CaP motor neuron defects and behavioral deficits induced by ROX can be rescued by administering ngn1 agonist (n=80). In summary, ROX exposure leads to early-life abnormalities in zebrafish motor neurons and locomotor behavior by hindering the differentiation of motor neuron progenitor cells and inducing abnormal apoptosis.