Histologic tissue response to furcation perforation repair using mineral trioxide aggregate or dental pulp stem cells loaded onto treated dentin matrix or tricalcium phosphate

Objectives The aim of this study is to compare the effect of treated dentine matrix (TDM) and tricalcium phosphate (TCP) scaffolds on odontogenic differentiation and mineralization of dental pulp stem cells (DPSCs) in furcation perforations created in the pulp chamber floor of premolar teeth in dogs. Material and methods DPSCs were isolated and cultured from the dental pulp of the maxillary left second and third premolars of dogs. The DPSCs were loaded on TCP (SC+TCP) and TDM (SC+TDM) scaffolds and inserted into intentionally perforated pulp chamber floors of premolars in dogs; six teeth were used for each group. Three more groups of six specimens were created, and mineral trioxide aggregate (MTA), TDM, and TCP were inserted into the perforations to act as controls. An intact premolar and no treatment in the perforation site were used as positive and negative controls respectively. After 3 months, the animals were sacrificed and the type of inflammation, presence of dentine, continuation and type of cementum, type of connective tissue, and presence of foreign body reaction were evaluated, and significant differences were between groups determined using the Fisher’s exact test. The evaluation of the amount of inflammation and the percentage of new bone formation was evaluated using the Mann-Whitney U test. Results The negative control group was associated with severe inflammation and granulation tissue formation. In the positive control group, intact periodontal tissues and no inflammation were observed. Dentine bridge formation was not seen in specimens of any group. The specimens in the SC+TDM group were associated with significantly more bone formation than other groups (P < 0.001). The amount of inflammation was less than 10 % in specimens of all groups with the exception of three specimens in the TCP group that were categorized as 10–30 %. Chronic inflammation without foreign body reactions was the major pattern of inflammation in groups. Formation of cementum with a cellular and continuous appearance was seen in all specimens. Conclusions SC+TDM was associated with significantly more bone formation when used to repair uninfected furcation perforations in the premolar teeth of dogs. Clinical relevance Application of TDM as a biological scaffold in combination with DPSCs may offer an advantage during the repair of root perforation defects

Extra virgin olive oil in maternal diet in, but high amount has deleterious effects creases osteogenic genes expression on bones in mice offspring at adolescence

Objective(s): Maternal high-fat diet has been shown to have deleterious effects on the offspring bones. However, there is no study to assess the effects of type and amount of maternal dietary oil in an isocaloric diet, with focus on extra virgin olive oil (EVOO). The objective of the current study was to test the hypothesis that type of maternal dietary oil has more effects than its amount in an isocaloric diet during gestation and lactation on bone genes expression in offspring in adolescence. Materials and Methods: Virgin female C57BL/6 mice were impregnated and fed either the AIN 93G diet (received 16 of calories as soybean oil, as a control diet, or EVOO) or a high fat AIN 93G diet (received 45 of calories as soybean oil or EVOO) from the time of vaginal plug confirmation until offspring�s weaning. Results: After adjusting for the amount of oils, osteoprotegerin/ receptor activator of nuclear factor NF-κB ligand (OPG/RANK-L) and OPG expressions were 6.1-and 2.8-folds higher in offspring born to EVOO compared with soybean oil-fed mothers. OPG, beta-catenin, and OPG/RANK-L expression were 88, 94, and 70 lower in offspring born to the 45 oil-fed mothers compared with the 16 group. In contrast, peroxisome proliferator-activated receptor gamma-2 (PPARγ2) gene expression was higher in the 45 oil group, adjusted for the types of oil. Conclusion: Maternal EVOO consumption, but not soybean oil increased osteoblastic gene expression, and high amounts of both oils decreased osteoblastic and increased adipogenic genes expression in adolescent offspring. � 2016, Mashhad University of Medical Sciences. All rights reserved

Functional differences of Toll-like receptor 4 in osteogenesis, adipogenesis and chondrogenesis in human bone marrow-derived mesenchymal stem cells

Multipotent human bone marrow-derived mesenchymal stem cells (hMSCs) are promising candidates for bone and cartilage regeneration. Toll-like receptor 4 (TLR4) is expressed by hMSCs and is a receptor for both exogenous and endogenous danger signals. TLRs have been shown to possess functional differences based on the species (human or mouse) they are isolated from therefore, the effects of knockdown of TLR4 were evaluated in humans during the differentiation of MSCs into bone, fat and chondrocyte cells in vitro. We investigated the expression profile of TLR4 during the differentiation of hMSCs into three different lineages on days 7, 14 and 21 and assessed the differentiation potential of the cells in the presence of lipopolysaccharide (LPS, as an exogenous agonist) and fibronectin fragment III-1c (FnIII-1c, as an endogenous agonist). TLR4 expression increased following the induction of hMSC differentiation into all three lineages. Alkaline phosphatase activity revealed that FnIII-1c accelerated calcium deposition on day 7, whereas LPS increased calcium deposition on day 14. Chondrogenesis increased in the presence of LPS; however, FnIII-1c acted as a reducer in the late stage. TLR4 silencing led to decreased osteogenesis and increased adipogenesis. Furthermore, Wnt5a expression was inversely related to chondrogenesis during the late stage of differentiation. We suggest that understanding the functionality of TLR4 (in the presence of pathogen or stress signal) during the differentiation of hMSCs into three lineages would be useful for MSC-based treatments. © 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd

Inhibition of hypertrophy and improving chondrocyte differentiation by MMP-13 inhibitor small molecule encapsulated in alginate-chondroitin sulfate-platelet lysate hydrogel

Background: Mesenchymal stem cells are a promising cell source for chondrogenic differentiation and have been widely used in several preclinical and clinical studies. However, they are prone to an unwanted differentiation process towards hypertrophy that limits their therapeutic efficacy. Matrix metallopeptidase 13 (MMP-13) is a well-known factor regulated during this undesirable event. MMP-13 is a collagen degrading enzyme, which is also highly expressed in the hypertrophic zone of the growth plate and in OA cartilage. Accordingly, we investigated the effect of MMP-13 inhibition on MSC hypertrophy. Methods: In this study, 5-bromoindole-2-carboxylic acid (BICA) was used as an inhibitory agent for MMP-13 expression. After identifying its optimal concentration, BICA was mixed into a hydrogel and the release rate was studied. To prepare the ideal hydrogel, chondroitin sulfate (CS) and platelet lysate (PL) were mixed with sodium alginate (Alg) at concentrations selected based on synergistic mechanical and rheometric properties. Then, four hydrogels were prepared by combining alginate (1.5w/v) and/or CS (1w/v) and/or PL (20v/v). The chondrogenic potential and progression to hypertrophy of human bone marrow-derived mesenchymal stem cell (hBM-MSC)-loaded hydrogels were investigated under free swelling and mechanical loading conditions, in the presence and absence of BICA. Results: Viability of hBM-MSCs seeded in the four hydrogels was similar. qRT-PCR revealed that BICA could successfully inhibit MMP-13 expression, which led to an inhibition of Coll X and induction of Coll-II, in both free swelling and loading conditions. The GAG deposition was higher in the group combining BICA and mechanical stimulation. Conclusions: It is concluded that BICA inhibition of MMP-13 reduces MSC hypertrophy during chondrogenesis. Graphical abstract: Figure not available: see fulltext. © 2020 The Author(s)

In vitro Growth and Characterization of Stem Cells from Human Dental Pulp of Deciduous Versus Permanent Teeth

Objective: By date investigations have indicated the presence of stem cells within the pulp tissue of both temporary and permanent human teeth. In the present study, these stem cells were compared in terms of their growth kinetics and culture requirements.Materials and Methods: Stem cells within the pulp of the human third molar (permanent tooth) and the deciduous incisor (temporary tooth) were isolated, culture-expanded and characterized. Then the proliferation potential of the cells was compared using multiplecell growth indices as PDT (Population doubling time), colonogenic activity and growth curve. Furthermore, the cultures of both cells were optimized for maximal proliferation.Results: Stem cells of either pulp tissue appeared as fibroblastic cells capable of differentiating into osteoblastic, odontoblastic, adipocytic and chondrocytic cell lineages. In contrast to molar stem cells, those from the incisor tooth expressed neurogenic markers of ßIII Tubulin and Tau. Based on in vitro growth data, the cells from third molar tended to have a lower PDT value (20.79, SD=2.8 versus 25.55, SD=2.9 hours), higher colonogenic activity and better growth curve than those from the deciduous incisor (P<0.05). Both cellsexhibited high expansion rate when being plated in a medium with 20% phosphate buffer solution at a density of 100 cells/cm2.Conclusion: Given the high proliferation capacity, the stem cells from the human third molar would be an appropriate candidate for use in experimental, preclinical and even clinical setups

Human Dental Pulp Stem Cells: The Culture Optimization for Increased Growth

&quot;nIntroduction: Dental pulp-derived mesenchymal stem cells (MSCs) have emerged as a promising tool for use in regenerative medicine. The in vitro growth kinetic and culture requirement of the cells derived from human dental pulp, which is the subject of this present study, is poorly described. &quot;nMaterials and Methods: Stem cells were derived from human third molar and then characterized. The in vitro growth kinetics of the cells was examined by colonogenic assay and a determination of the population doubling number (PDN). Finally, the culture conditions were optimized for pulp stem cell maximum proliferation. &quot;nResults: Propagated dental pulp cells tended to differentiate into odontoblast, osteoblast, adipose and cartilage cells. Typically surface antigens were expressed as mesenchymal stem cells. The cells tended to be very proliferative with a PDN value of about 11. The colonogenic efficiency was about 60% and an average colony size was about 10.75&amp;plusmn;1.58 mm2. The best culture condition for enhanced proliferation was achieved when the cells were seeded at 100 cells/cm2 in a the presence of 20% FBS in a medium (P&amp;lt;0.05). &quot;nConclusion: Taken together, the optimal culture conditions for human dental pulp-derived MSCs were determined. This information is helpful with respect to cell in vitro propagation which is greatly needed prior to their transplantation

3D-porous β-tricalcium phosphate�alginate�gelatin scaffold with DMOG delivery promotes angiogenesis and bone formation in rat calvarial defects

Hypoxia-inducible factor-1α (HIF-1α), a well-studied angiogenesis pathway, plays an essential role in angiogenesis-osteogenesis coupling. Targeting the HIF-1a pathway frequently leads to successful reconstruction of large-sized bone defects through promotion of angiogenesis. Dimethyloxalylglycine (DMOG) small molecule regulates the stability of HIF-1α at normal oxygen tension by mimicking hypoxia, which subsequently accelerates angiogenesis. The current study aims to develop a novel construct by seeding adipose derived mesenchymal stem cells (ADMSCs) onto a scaffold that contains DMOG to induce angiogenesis and regeneration of a critical size calvarial defect in a rat model. The spongy scaffolds have been synthesized in the presence and absence of DMOG and analyzed in terms of morphology, porosity, pore size, mechanical properties and DMOG release profile. The effect of DMOG delivery on cellular behaviors of adhesion, viability, osteogenic differentiation, and angiogenesis were subsequently evaluated under in vitro conditions. Histological analysis of cell-scaffold constructs were also performed following transplantation into the calvarial defect. Physical characteristics of fabricated scaffolds confirmed higher mechanical strength and surface roughness of DMOG-loaded scaffolds. Scanning electron microscopy (SEM) images and MTT assay demonstrated the attachment and viability of ADMSCs in the presence of DMOG, respectively. Osteogenic activity of ADMSCs that included alkaline phosphatase (ALP) activity and calcium deposition significantly increased in the DMOG-loaded scaffold. Computed tomography (CT) imaging combined with histomorphometry and immunohistochemistry analysis showed enhanced bone formation and angiogenesis in the DMOG-loaded scaffolds. Therefore, spongy scaffolds that contained DMOG and had angiogenesis ability could be utilized to enhance bone regeneration of large-sized bone defects. Figure not available: see fulltext.. © 2018, Springer Science+Business Media, LLC, part of Springer Nature