Influence of different finishing and polishing protocols of composite CAD CAM blocks on surface roughness and biological response of gingival mesenchymal stem cells.

Background Toothpaste is the most commonly used personal care products for maintaining oral hygiene. Its composition varies based on its intended purpose, with surfactants being one key ingredient, notable for their cleaning and foaming properties. In addition, fluoride, which is considered the most effective agent in preventing caries, is frequently included in toothpaste formulas. During brushing, gingival tissue is exposed to these components. Gingiva is a tissue from which gingival mesenchymal stem cells with healing and regeneration potential can be isolated. The objective of this study was to evaluate the effects of these components on the viability of gingival mesenchymal stem cells in real-time. Objectives This study aimed to evaluate, in real-time, the cytotoxic effects that may occur on gingival epithelial stem cells exposed to toothpastes with varying surfactant contents and fluoride. Methods Tissue samples for the isolation of gingival mesenchymal stem cells (GMSCs) were obtained during the extraction of impacted third molars. Solutions were prepared from ROCS Mg toothpaste containing sodium lauryl sulfate (SLS), Cocoamidopropyl betaine (CAPB), and ROCS Sensitive containing sodium lauryl sarcosinate, SLS, and Colgate toothpaste with1450 ppm fluoride. Dulbecco's modified eagle medium was used as the negative control group. Cell viability was evaluated in real time with the xCelligence device. Two-way ANOVA was used to evaluate the effects of concentration and toothpaste type, and Tukey Post hoc tests were used for pairwise comparisons. Statistical significance was determined as 0.05 in the study. Results Colgate toothpaste containing SLS and 1450 ppm fluoride exhibited a statistically significantly lower cell viability compared to the other tested toothpastes (p<0.05). This was followed by ROCS Mg toothpaste, which did not contain fluoride but included SLS. ROCS Sensitive toothpaste, containing CAPB and sodium lauryl sarcosinate, showed the highest cell viability. As the concentration of toothpastes increased, a decrease in cell viability was observed. Conclusions As a result of the findings, it was seen that toothpastes containing SLS and fluoride had a more negative effect on the viability of GMSC cells than toothpastes containing different surfactants.

In routine dental care, various dental luting cements are utilized to cement the dental prosthesis. Thus, the aim of the current study was to assess the Cytotoxic effect of three different dental luting cements on human gingival mesenchymal stem cell and evaluation of cytokines and growth factors release. Cytotoxicity of glass ionomer cement (GIC), resin modified glass ionomer cement (RMGIC) and resin cement (RC) on the human gingival mesenchymal stem cells (HGMSCs) was evaluated. Amongst the cements tested, least cytotoxic cement was further tested for the release of cytokines and growth factors. MTT test was used to evaluate the cytotoxicity of the dental luting cements at 1 h, 24 h, and 48 h on HGMSCs. Cytokines such as interleukin (IL) 1α & IL 8 and growth factors such as platelet derived growth factor & transforming growth factor beta release from the least cytotoxic RC was evaluated using flow cytometry analysis. The mean absorbance values by MTT assay and cell viability at various time intervals between four groups were compared using a one way analysis of variance test and Tukey's post hoc test. The least cytotoxic RC group and the control group's mean levels of cytokines and growth factors were compared using the Mann-Whitney test. As exposure time increased, the dental luting cement examined in this study were cytotoxic. RC was the least cytotoxic, RMGIC was moderate and glass ionomer cement showed the highest cytotoxic effect. Concomitantly, a significant positive biological response of gingival mesenchymal stem cells with the release of ILs when exposed to the RC was observed. For a fixed dental prosthesis to be clinically successful over the long term, it is imperative that the biocompatibility of the luting cement be taken into account in order to maintain a healthy periodontium surrounding the restoration.

Objective: The objective of this study was to investigate the morphology, proliferation, and differentiation of gingival mesenchymal stem cells (GMSCs) irradiated with a 970 nm Diode Laser (LLLT). It is essential to validate the efficacy of treatment, optimize irradiation conditions and guarantee the safety and quality of stem cells for future use in dental applications. Materials and Methods: GMSCs were cultured in standard conditions and irradiated with a Diode laser (970 nm, 0.5W) with an energy density of 9J/cm2. Cell proliferation was assessed with the WST-1 proliferation kit. GMSCs were differentiated into chondrogenic and osteogenic lineages. Cell morphology was performed with Hematoxylin/eosin staining, and quantitative nuclear analysis was done. Cell viability was monitored with trypan blue testing. Results: GMSCs subjected to irradiation demonstrated a significant increase in proliferation at 72 hours compared to the non-irradiated controls (p=0.027). This indicates that the 970 nm diode laser has a stimulatory effect on the proliferation of GMSCs. LLLT-stimulated GMSCs exhibited the ability to differentiate into chondrogenic and osteogenic lineages. A substantial decrease in cell viability was observed 24 hours after irradiation (p=0.024). However, after 48 hours, the cell viability recovered without any significant differences. This indicates that there might be a temporary negative impact on cell viability immediately following irradiation, but the cells were able to recover and regain their viability over time. Conclusions: This study support that irradiation with a 970 nm diode laser could stimulate the proliferation of GMSCs, maintain their ability to differentiate into chondrogenic and osteogenic lineages, and has minimal impact on the mor- phological characteristics of the cells. These results support the potential use of NIR Lasers in combination with GMSCs as a promising strategy for dental treatments. Keywords: Photobiomodulation; semiconductor lasers; Mesenchymal stem cells; Gingiva; Cell Proliferation; Safety.

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a clinical condition that specifically occurs in the oral cavity, characterized by retarded wound healing in oral mucosa accelerating the exposure of bone. Moreover, the pathological mechanism remains poorly understood. Gingival mesenchymal stem cells (GMSCs) play a critical role in gingival healing and soft tissue regeneration. Although previous studies have showed that bisphosphonates (BPs) are highly toxic to healthy GMSC, there is overall lack of direct evidence demonstrating the characterization of GMSCs derived from BRONJ patients. In present study, we isolated GMSCs for the first time from the central area of BRONJ patients’ gingiva (center-BRONJ GMSCs) and the peripheral area (peri-BRONJ GMSCs), and found that they exhibited decreased proliferation, adhesion, migration capacities and underwent early apoptosis in vitro compared control GMSCs. Notably, the central and peripheral BRONJ GMSCs transplantation in a mice excisional skin model also displayed lower cell survival rate and poor healing effects than that of controls. Mechanistically, TGF-β1 signaling pathway was suppressed not only in BRONJ patients’ gingival lesions but also in BRONJ GMSCs transplantation animal model. The results above suggested that under the microenvironment of BRONJ patients, the dysfunction of GMSCs and the suppressed TGF-β1 signaling pathway may be the vital factors in impaired gingival healing, thus contributing to persistent exposure of underlying bone and development of BRONJ. This study provides new insights into the prevention for BRONJ by improving the functions of GMSCs and upregulating TGF-β1 in accelerating gingival wound healing.Graphical Schematic illustration of the dysfunction of BRONJ GMSCs in vitro and BRONJ GMSCs transplantation in a mice skin model delaying cutaneous wound healing mainly via suppressing TGF-β1 signaling pathway.

Mesenchymal stem cells (MSCs) have the capacity to maintain immune homeostasis and prevent autoimmunity. However, it is unclear whether human-derived gingival mesenchymal stem cells (GMSCs) can suppress human T cell-mediated diseases. GMSCs were isolated from human gingival tissues. GMSCs were cultured with allogeneic T cells which labeled with CFSE, and cell proliferation was evaluated by CFSE dilution in FACS. In other experiments, human PBMCs were stimulated with LPS with a ratio of PBMCs to GMSCs at 1:5. After 3 days, intracellular cytokine including IL-4, IL-17, and IFN-γ in CD4+ cells were determined by FACS. Mouse xeno-GVHD Model was induced in NOD/SCID mice, GMSCs or human fibroblasts (negative control) or human bone marrow mesenchymal stem cells (positive control) were intravenously into mice. Weight loss and symptoms of GVHD were assessed. We observed that GMSCs potently suppress the proliferation of T cells and differentiation of PBMC in vitro, and that co-transfer of GMSC but not fibroblast and human PBMC significantly prolonged xeno-GVHD mouse survival. We also demonstrated that GMSC is even better than BMSC on treating xeno-GVHD. We further revealed that GMSCs inhibit human PBMCs-initiated xenogenic responses via CD39 and IDO signals. GMSCs can suppress human immune responses and immune system-mediated diseases, offering a potential clinical option to be used for modulating GVHD and other autoimmune diseases.

BackgroundDiabetes is a common disease that causes gingival and periodontal problems. Stem cells isolated from dental sources are an emerging area of research with a potential to facilitate regenerative medicine. The stem cells retain the property of self-renewal and the ones isolated from dental sources are mainly multipotent mesenchymal stem cells that have the ability to self-renew as well as differentiation towards multiple lineages.ObjectivesWe aimed to isolate and characterize gingival mesenchymal stem cells by pluripotency markers and investigated the effect of oxidative stress on growth kinetics and apoptotic gene expression of gingival cells exposed to glucose mediated oxidative stress.MethodsIn this study, we isolated gingival mesenchymal stem cells from gingiva. This was followed by morphologic analysis using inverted phase contrast microscopy and molecular profiling of these cells for the mRNA expression of specific genes. The isolated cells were cultured till passage 3 and then exposed to oxidative stress (high glucose concentration). We measured the apoptotic gene expression and compared their growth kinetics.ResultsThe results showed that oxidative stress produced by glucose reduced growth kinetics and increased apoptotic gene expression in gingival mesenchymal stem cells. According to the genetic results, glucose activated TNF family to initiate apoptosis.ConclusionIn conclusion, the present study demonstrated that high glucose obliterated cellular proliferation testified by evaluating growth kinetics and induced apoptotic gene expression in gingival mesenchymal stem cells. This initiated extrinsic apoptotic pathway mediated by TNF family. Therefore, in diabetes oral health condition is compromised and periodontal disease is common.

The important role of the Wnt/β-catenin signaling pathway in small molecules mediated gingival mesenchymal stem cells transdifferentiate into neuron-like cells

BackgroundMounting evidence has shown that a novel subset of mesenchymal stem cells (MSCs) derived from human gingiva referred to as gingival mesenchymal stem cells (GMSCs) displays a greater immunotherapeutic potential and regenerative repair expression than MSCs obtained from other tissues. However, the safety of the use of transplanted GMSCs in humans remains unclear.MethodsIn this study, we evaluated the safety of GMSCs transplanted into mouse, rat, rabbit, beagle dog, and monkey as well as two animal models of autoimmune diseases.ResultsIn short- and long-term toxicity tests, infused GMSCs had no remarkable adverse effects on hematologic and biochemical indexes, particularly on the major organs such as heart, liver, spleen, and kidney in recipient animals. It was also shown that GMSCs were well tolerated in other assays including hemolysis, vascular, and muscular stimulation, as well as systemic anaphylaxis and passive skin Arthus reaction in animal models. GSMC infusion did not cause any notable side effects on animal models of either autoimmune arthritis or lupus. Significantly, GMSCs most likely play no role in genotoxicity and tumorigenesis. The biological features remained stable for an extended period after cell transfer.ConclusionsGMSCs are safe in various animal models of autoimmunity, even during active disease episodes, especially in monkeys. This study paves a solid road for future clinical trials of GMSCs in patients with autoimmune and inflammatory diseases.

Restenosis is the major factor influencing the long-term success rate of angioplasty and stent implantation and effective strategies to prevent restenosis remain limited. Mesenchymal stem cells (MSCs) are pluripotent stem cells capable of self-renewal and multidirectional differentiation, which may be able to promote endothelium repair, thereby reducing restenosis. The present study aimed to evaluate the effects of adipose MSCs (AMSCs) and gingival MSCs (GMSCs) on endothelium repair. MSCs were isolated from two human tissue types, namely adipose tissue and gingival tissue, and the effects of AMSCs and GMSCs in ex vivo endothelium repair and on vascular smooth muscle cell (SMC) growth were examined. To compare the feasibility of using AMSCs and GMSCs for the repair of endothelium damage in endothelial cell (EC) damage and vasoproliferative disorders, an ex vivo model of endothelium repair in a co-culture system was developed. It was indicated that AMSCs and GMSCs expressed characteristic MSC markers (CD105 and CD166). 3H-thymidine incorporation in the co-culture group of AMSCs and SMCs in the presence of ECs was lower compared with that in the GMSC and SMC co-culture group. The protein expression level of proliferating cell nuclear antigen in the co-culture group of AMSCs and SMCs in the presence of ECs were lower compared with that in the GMSC and SMC co-culture group. After co-culture with ECs for 5 days, 25.71±3.08% of AMSCs began to express CD31 protein and 20.06±2.09% of GMSCs began to express CD31 protein. Furthermore, anti-VEGF antibody was able to inhibit MSC differentiation. Collectively, the present results suggested that seeding of AMSCs had a stronger effect to inhibit the proliferation and migration of SMCs compared with GMSCs.

Effect of laser treatment on the attachment and viability of mesenchymal stem cell responses on shape memory NiTi alloy

Dental mesenchymal stem cells encapsulated in an alginate hydrogel co-delivery microencapsulation system for cartilage regeneration

Comparative analysis of lncRNA and mRNA expression profiles between periodontal ligament stem cells and gingival mesenchymal stem cells

The aim of this study was to construct crosslinked polylysine-hyaluronic acid microspheres (pl-HAM) ladened with gingival mesenchymal stem cells (GMSCs) and explore its biologic behavior in soft tissue regeneration. The effects of the crosslinked pl-HAM on the biocompatibility and the recruitment of L-929 cells and GMSCs were detected in vitro. Moreover, the regeneration of subcutaneous collagen tissue, angiogenesis and the endogenous stem cells recruitment were investigated in vivo. We also detected the cell developing capability of pl-HAMs. The crosslinked pl-HAMs appeared to be completely spherical-shaped particles and had good biocompatibility. L-929 cells and GMSCs grew around the pl-HAMs and increased gradually. Cell migration experiments showed that pl-HAMs combined with GMSCs could promote the migration of vascular endothelial cells significantly. Meanwhile, the green fluorescent protein-GMSCs in the pl-HAM group still remain in the soft tissue regeneration area 2weeks after surgery. The results of in vivo studies showed that denser collagen deposition and more angiogenesis-related indicator CD31 expression in the pl-HAMs+ GMSCs + GeL group compared with the pl-HAMs + GeL group. Immunofluorescence showed that CD44, CD90, CD73 co-staining positive cells surrounded the microspheres in both pl-HAMs + GeL group and pl-HAM + GMSCs + GeL group. The crosslinked pl-HAM ladened with GMSCs system could provide a suitable microenvironment for collagen tissue regeneration, angiogenesis and endogenous stem cells recruitment, which may be an alternative to autogenous soft tissue grafts for minimally invasive treatments for periodontal soft tissue defects in the future.

Gingival mesenchymal stem cells attenuate pro-inflammatory macrophages stimulated with oxidized low-density lipoprotein and modulate lipid metabolism

Purpose: To investigate the influence of sodium hypochlorite (NaOCl) on human dental stem cell proliferation and differentiation. Method: Dental pulp stem cells (DPSCs), periodontal ligament stem cell (PDLSCs), and gingival mesenchymal stem cells (GMSCs) were treated with NaOCl. Cell viability was evaluated with cellular counting kit-8 (CCK8), and cellular adenosine triphosphate (ATP) levels were analyzed by bromodeoxyuridine (BrdU) incorporation and subsequent flow cytometry. Quantitative polymerase chain reaction (qPCR) and western blotting were performed to detect the expressions of differentiation markers. Results: The viability and ATP levels of all three stem cells types were impaired by NaOCl in a concentration- and time-dependent manners. However, the decrease ATP in GMSCs was less than the other two stem cell population (p < 0.05). NaOCl treatment significantly suppressed the proliferation of dental stem cells (p < 0.05). With regard to differentiation marker expression levels, the decrease in Stro-1 was greater in treatment groups when compared to control on Day 7, while increase in levels of dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP), and osteocalcin (OC) was smaller (p < 0.05). The expressional changes of Stro-1, DSPP, BSP, and OC were more prominent in DPSMs and PDLSCs than in GMSCs. Conclusion: NaOCl dose-dependently impairs the viability, proliferation and differentiation of dental stem cells. Thus, its toxicity to dental stem cells needs to be considered in clinical application. Keywords: Dental stem cells, Sodium hypochlorite, Viability, Proliferation, Differentiation