Search

BACKGROUND: Dental pulp stem cells are one of the stem cells with great potential in oral and maxillofacial tissue engineering. Compared with mesenchymal stem cells, dental pulp stem cells have the advantages of convenient collection, less ethical problems and higher potential of proliferation and differentiation. Currently, except for biochemical factors, physical stimulation also plays a critical role in the osteogenic/odontogenic differentiation of dental pulp stem cells. OBJECTIVE: To review the relevant physical factors and the possible signaling pathway affecting the osteogenic/odontogenic differentiation of dental pulp stem cells to find the optimal induction conditions affecting their differentiation. METHODS: PubMed and CNKI databases were searched for relevant articles using “dental pulp stem cells (DPSCs), osteogenesis differentiation, odontoblastic differentiation, hypoxia, mechanical force, laser therapy, magnetic fields, microgravity” as English and Chinese search terms. Seventy-nine articles regarding physical factors affecting osteogenic/odontogenic differentiation of dental pulp stem cells were selected for the review. RESULTS AND CONCLUSION: Direct or indirect physical signals in the microenvironment have shown broad application prospects in regulating the directed differentiation of stem cells. Many related physical factors, for example, hypoxia, mechanical stimulation (dynamic hydrostatic pressure, mechanical tension, shear force, etc.), laser, microgravity, and magnetic field, have positive influences on the osteogenic/odontogenic differentiation of dental pulp stem cells. Owing to the complex mechanical environment of stomatognathic system, mechanical stimulation is a key physical factor in changing cellular environment and is also a frontier in tissue engineering. It will provide new ideas for investigating the response of dental pulp stem cells to the mechanical environment in the diagnosis and treatment of oral diseases. Because this field is relatively “young”, the parameters of equipment have not been unified and the relevant results are not consistent. The optimal induction parameters and conditions of related physical factors should be further explored and optimized. Scaffold material, one of the three elements of tissue engineering, plays a role in promoting the osteogenic/odontogenic differentiation of dental pulp stem cells, and promotes the development of materials science and clinical technology. The signaling pathways involve Notch, Wnt, MAPK, etc. The biological basis of regulating the behavior of dental pulp stem cells is not clear. The specific mechanism will be further explored in the future to provide new ideas for dental pulp regeneration and bone tissue engineering under the influence of physical factors. [ABSTRACT FROM AUTHOR]

The transplantation of collagen hydrogels encapsulating human dental pulp stem cell (DPSC)‐derived chondrogenic cells is potentially a novel approach for the regeneration of degenerated nucleus pulposus (NP) and cartilage. Grafted cell migration allows cells to disperse in the hydrogels and the treated tissue from the grafted location. We previously reported the cell migration in type I and type II hydrogels. It is important to explore further how cell culture time affect the cell motility. In this study, we observed the decreased motility of DPSC‐derived chondrogenic cells after culturing for 2 weeks compared with cells cultured for 2 days in these gels. The Alamarblue assay showed the cell proliferation during the two‐week cell culture period. The findings suggest that the transitions of cell motility and proliferation during the longer culture time. The result indicates that the early culture stage is an optimal time for cell transplantation. In a degenerated disc, the expression of IL‐1β and TNFα increased significantly compared with healthy tissue and therefore may affect grafted cell migration. The incorporation of IL‐1β and TNFα into the collagen hydrogels decreased cell motility. The study indicates that the control of IL‐1β and TNFα production may help to maintain cell motility after transplantation. [ABSTRACT FROM AUTHOR]

Secretome Dental Pulp Stem Cells have been proposed as a new alternative for wound burn. The aim of this study is to compare Secretome Dental Pulp Stem Cells and MEBO ointment against several fibroblasts and collagen in the healing process of superficial dermal burns. This study used a post-test only controlled group design by using 15 rats that were given superficial dermal burned wounds. Rats were divided into a negative control group of NaCl 0.9% (K1), a treatment group of MEBO (K2), and a treatment group of DPSCs-secretome (K3). Histopathology was done on the 5th, 14th, and 21st days post-induction wound burn. Network-prepared histopathology by colouring Messon Trichomes. Then, it was observed under a microscope with 200x magnification. Scoring in a way semi-qualitative for assessing fibroblasts and collagen. The total score of fibroblasts in the MEBO group was higher than the DPSCs-secretome group on day 5th. In comparison, the score for increasing the amount of collagen in the DPSCs-secretome group on days 5th and 14th was higher than the MEBO group. DPSCs-secretome has better effectiveness in increasing the amount of collagen but not better in increasing fibroblasts compared to MEBO. [ABSTRACT FROM AUTHOR]

Parkinson′s disease (PD) is the second most common neurodegenerative disease, mainly due to the loss of dopaminergic neurons in the substantia nigra (SN) of the midbrain, resulting in motor dysfunction. Dental stem cells (DSCs) are derived from the cranial neural crest which can be easily harvested. DSCs coming from the cranial neural crest have excellent proliferation and differentiation ability, and can promote nerve repair and regeneration. DSCs can secrete new dopamine neurons and secrete a large number of neurotrophic factors (NTFs) to improve the neural function, and also inhibit the neuroinflammatory response through immune modulation. DSCs can effectively alleviate the motor dysfunction in rats with PD and play an important role in R&D of regenerative medicine. [ABSTRACT FROM AUTHOR]

Simple Summary: When joints are harmed due to injury, inheritance, or aging, it is difficult for the body to heal damaged cartilage. This is a major cause of pain and disability worldwide. With increasing life expectancy, millions of adults are affected, and enormous costs are imposed on health care systems. Scientists are attempting to use stem cells to create new cartilage-like tissue as a potential solution. However, the most suitable stem cell type for cartilage repair has not been defined. This study compared the ability to generate cartilage-like tissue by using two stem cell types that were derived from human bone marrow and dental pulp. To produce cartilage, the tissue's environment should be simulated for stem cells in a laboratory. Therefore, the low-oxygen tension of joint cartilage was simulated using a simple and inexpensive chemical, cobalt chloride. The results showed that dental pulp stem cells could produce higher quality tissue that closely resembled human joint cartilage in terms of its structure and organization that could form the primary base of normal function. While further research is necessary, these initial findings represent a promising step toward using stem cells more beneficially to enhance a patient's quality of life. The limited self-repair capacity of articular cartilage is a challenge for healing injuries. While mesenchymal stem/stromal cells (MSCs) are a promising approach for tissue regeneration, the criteria for selecting a suitable cell source remain undefined. To propose a molecular criterion, dental pulp stem cells (DPSCs) with a Hox-negative expression pattern and bone marrow mesenchymal stromal cells (BMSCs), which actively express Hox genes, were differentiated towards chondrocytes in 3D pellets, employing a two-step protocol. The MSCs' response to preconditioning by cobalt chloride (CoCl2), a hypoxia-mimicking agent, was explored in an assessment of the chondrogenic differentiation's efficiency using morphological, histochemical, immunohistochemical, and biochemical experiments. The preconditioned DPSC pellets exhibited significantly elevated levels of collagen II and glycosaminoglycans (GAGs) and reduced levels of the hypertrophic marker collagen X. No significant effect on GAGs production was observed in the preconditioned BMSC pellets, but collagen II and collagen X levels were elevated. While preconditioning did not modify the ALP specific activity in either cell type, it was notably lower in the DPSCs differentiated pellets compared to their BMSCs counterparts. These results could be interpreted as demonstrating the higher plasticity of DPSCs compared to BMSCs, suggesting the contribution of their unique molecular characteristics, including their negative Hox expression pattern, to promote a chondrogenic differentiation potential. Consequently, DPSCs could be considered compelling candidates for future cartilage cell therapy. [ABSTRACT FROM AUTHOR]

Background: Subarachnoid hemorrhage (SAH) is a severe stroke subtype that lacks effective treatment. Exosomes derived from human dental pulp stem cells (DPSCs) are a promising acellular therapeutic strategy for neurological diseases. However, the therapeutic effects of DPSC-derived exosomes (DPSC-Exos) on SAH remain unknown. In this study, we investigated the therapeutic effects and mechanisms of action of DPSC-Exos in SAH. Materials and methods: SAH was established using 120 male Sprague-Dawley rats. One hour after SAH induction, DPSC-Exos were administered via tail vein injection. To investigate the effect of DPSC-Exos, SAH grading, short-term and long-term neurobehavioral assessments, brain water content, western blot (WB), immunofluorescence staining, Nissl staining, and HE staining were performed. The role of miR-197-3p/FOXO3 in regulating pyroptosis was demonstrated through miRNA sequencing, bioinformatics analysis, and rescue experiments. The SAH model in vitro was established by stimulating BV2 cells with hemoglobin (Hb) and the underlying mechanism of DPSC-Exos was investigated through WB and Hoechst/PI staining. Results: The expressions of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) were increased after SAH. DPSC-Exos alleviated brain edema and neuroinflammation by inhibiting the expression of FOXO3 and reducing NLRP3 inflammasome activation, leading to improved neurobehavioral functions at 24 h after SAH. In vitro, the expression of the NLRP3 inflammasome components (NLRP3 and caspase1-p20), GSDMD-N, and IL-18 was inhibited in BV2 cells pretreated with DPSC-Exos. Importantly, DPSC-Exos overexpressing miR-197-3p had a more obvious protective effect than those from NC-transfected DPSCs, while those from DPSCs transfected with the miR-197-3p inhibitor had a weaker protective effect. Functional studies indicated that miR-197-3p bound to the 3ʹ-untranslated region of FOXO3, inhibiting its transcription. Furthermore, the overexpression of FOXO3 reversed the protective effects of miR-197-3p. Conclusions: DPSC-Exos inhibited activation of the NLRP3 inflammasome and related cytokine release via the miR-197-3p/FOXO3 pathway, alleviated neuroinflammation, and inhibited microglial pyroptosis. These findings suggest that using DPSC-Exos is a promising therapeutic strategy for SAH. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of human pulp stem cells （hDPSC) -derived exosomes （Exo） modified by circRNA （circRNA） signal-induced proliferation-associated protein-like 1（SIPA1L1） on the angiogenesis of human umbilical vein endothelial cells （HUVEC). Methods hDPSC was isolated and cultured from pulp tissue, the circSIPA1L1 overexpression plasmid was transfected into hDPSC, and Exo was isolated and identified. HUVEC was divided into control group, hDPSC Exo group and circSIPA1L1-hDPSC Exo group. After culture for 48 h, the vasculoformation ability was detected by Matrigel matrix gel vasculoformation test, the expression levels of vascular endothelial growth factor （VEGF), vascular endothelial growth factor receptor 2（VEGFR2） and placental growth factor （PGF） were determined by qRT-PCR and Western blot. Results The Exo was successfully isolated from the untransfected hDPSC and the hDPSC transfected with circSIPA1L1, and compared with the HDPSC-derived Exo, the relative expression of circSIPA1L1 in the hDPSC Exo transfected with circSIPA1L1 was significantly up-regulated （P < 0.05). Compared with hDPSC Exo group, the number of HUVEC tubular structures in circSIPA1L1-hDPSC Exo group was significantly increased （P < 0.05), and the mRNA and protein relative expressions of VEGF, VEGFR2 and PGF were also significantly up-regulated （P < 0.05）. Conclusions Modification of hDPSC-derived Exo by circRNA SIPA1L1 can promote angiogenesis, and the mechanism may be related to up-regulation of VEGF, VEGFR2 and PGF expression levels. [ABSTRACT FROM AUTHOR]

Objective: We aimed to identify the crucial genes involved in dental pulp stem cell (DPSC) senescence and evaluate the impact of melatonin on DPSC senescence. Methods: Western blotting, SA‐β‐Gal staining and ALP staining were used to evaluate the senescence and differentiation potential of DPSCs. The optimal concentration of melatonin was determined using the CCK‐8 assay. Differentially expressed genes (DEGs) involved in DPSC senescence were obtained via bioinformatics analysis, followed by RT–qPCR. Gain‐ and loss‐of‐function studies were conducted to explore the role of MMP3 in DPSC in vitro expansion and in response to melatonin. GSEA was employed to analyse MMP3‐related pathways in cellular senescence. Results: Treatment with 0.1 μM melatonin attenuated cellular senescence and differentiation potential suppression in DPSCs due to long‐term in vitro expansion. MMP3 was a crucial gene in senescence, as confirmed by bioinformatics analysis, RT–qPCR and Western blotting. Furthermore, gain‐ and loss‐of‐function studies revealed that MMP3 played a regulatory role in cellular senescence. Rescue assays showed that overexpression of MMP3 reversed the effect of melatonin on senescence. GSEA revealed that the MMP3‐dependent anti‐senescence effect of melatonin was associated with the IL6‐JAK‐STAT3, TNF‐α‐Signalling‐VIA‐NF‐κB, COMPLEMENT, NOTCH Signalling and PI3K‐AKT‐mTOR pathways. Conclusion: Melatonin attenuated DPSC senescence caused by long‐term expansion by inhibiting MMP3. [ABSTRACT FROM AUTHOR]

Research on tooth regeneration using human-induced pluripotent stem cells (hiPSCs) is valuable for autologous dental regeneration. Acquiring mesenchymal and epithelial cells as a resource for dental regeneration is necessary because mesenchymal–epithelial interactions play an essential role in dental development. We reported the establishment of hiPSCs-derived dental epithelial-like cell (EPI-iPSCs), but hiPSCs-derived dental mesenchymal stem cells (MSCs) have not yet been reported. This study was conducted to establish hiPSCs-derived MSCs and to differentiate them into dental cells with EPI-iPSCs. Considering that dental MSCs are derived from the neural crest, hiPSCs were induced to differentiate into MSCs through neural crest formation to acquire the properties of dental MSCs. To differentiate hiPSCs into MSCs through neural crest formation, established hiPSCs were cultured and differentiated with PA6 stromal cells and differentiated hiPSCs formed neurospheres on ultralow-attachment plates. Neurospheres were differentiated into MSCs in serum-supplemented medium. Neural crest-mediated MSCs (NC-MSCs) continuously showed typical MSC morphology and expressed MSC markers. After 8 days of odontogenic induction, the expression levels of odontogenic/mineralization-related genes and dentin sialophosphoprotein (DSPP) proteins were increased in the NC-MSCs alone group in the absence of coculturing with dental epithelial cells. The NC-MSCs and EPI-iPSCs coculture groups showed high expression levels of amelogenesis/odontogenic/mineralization-related genes and DSPP proteins. Furthermore, the NC-MSCs and EPI-iPSCs coculture group yielded calcium deposits earlier than the NC-MSCs alone group. These results indicated that established NC-MSCs from hiPSCs have dental differentiation capacity with dental epithelial cells. In addition, it was confirmed that hiPSCs-derived dental stem cells could be a novel cell source for autologous dental regeneration. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sema3A is a power secretory osteoprotective factor. However, studies about Sema3A-modified dental pulp stem cells (Sema3A-DPSCs) are rare. OBJECTIVE: To explore the osteogenic differentiation ability of Sema3A-DPSCs and their regulatory effect on the osteogenic differentiation of the pre-osteoblast cell line MC3T3-E1. METHODS: First, Sema3A-DPSCs were constructed using a lentivirus infection system carrying the Sema3A gene. Control lentivirus-treated DPSCs (Vector-DPSCs) were used as controls. Sema3A-DPSCs or Vector-DPSCs were co-cultured with proosteoblast line MC3T3-E1 at the ratio of 1 ∶ 1 and 1 ∶ 3 for 24 hours. Finally, the Sema3A-DPSCs, Vector-DPSCs and their co-cultured cells with MC3T3-E1 were cultured for osteogenic induction and differentiation. Osteogenic gene expression was detected by alkaline phosphatase staining, alizarin red staining and real-time quantitative RT-PCR to evaluate osteogenic differentiation ability. RESULTS AND CONCLUSION: (1) Sema3A mRNA and protein expression levels in Sema3A-DPSCs were significantly up-regulated. The level of secreted Sema3A in cell supernatant was up-regulated. (2) Compared with the Vector-DPSCs, mRNA expressions of osteogenic genes alkaline phosphatase, Runtrelated transcription factor 2, osteocalcin and Sp7 transcription factors in Sema3A-DPSCs were up-regulated; the activity of alkaline phosphatase was enhanced, and the formation of mineralized nodules increased. (3) There were no obvious differences in proliferation between Sema3A-DPSCs and VectorDPSCs. (4) Compared with MC3T3-E1/Vector-DPSCs co-culture system, the expression of MC3T3-E1 osteogenic genes was up-regulated, and the total alkaline phosphatase activity was enhanced and more mineralized nodules were formed in the MC3T3-E1/Sema3A-DPSCs co-culture system. (5) The results suggest that overexpression of Sema3A can enhance the osteogenic differentiation of DPSCs. Overexpression of Sema3A in DPSCs can promote osteogenic differentiation of MC3T3-E1 in the DPSCs/MC3T3-E1 co-culture system. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effect of IWP‐2, Wnt inhibitor, on human dental pulp stem cells (hDPSCs) responses. Methodology: hDPSCs were isolated from human dental pulp tissues. Cells were treated with 25 μM IWP‐2 for 24 h, and subsequently, the gene expression profile was examined using high‐throughput RNA sequencing. The mRNA expression was analysed using qPCR. The effect of IWP‐2 was investigated in both normal and LPS‐induced hDPSCs (inflamed hDPSCs). CD4+ T cells and CD14+ monocyte‐derived macrophages were cultured with conditioned media of IWP‐2 treated hDPSCs to observe the immunosuppressive property. Results: RNA sequencing indicated that IWP‐2 significantly downregulated several KEGG pathways, including cytokine‐cytokine receptor interaction, IL‐17 signalling pathway, and TNF signalling pathway. In both normal and inflamed conditions, IWP‐2 markedly upregulated TGFB1 mRNA expression while the mRNA expression of pro‐inflammatory cytokines, TNFA, IL1B, IFNG, and IL6, was inhibited. In the inhibition experiment, the pretreatment with p38, MAPK, or PI3K inhibitors abolished the effects of IWP‐2 in LPS‐induced inflammation. In terms of immune cells, IWP‐2‐treated‐inflamed hDPSCs conditioned media attenuated T cell proliferation and regulated regulatory T cell differentiation. In addition, the migratory property of macrophage was decreased after being exposed to IWP‐2‐treated inflamed hDPSCs conditioned media. Conclusion: IWP‐2 suppressed inflammatory cytokine expression in both normal and inflamed hDPSCs. Moreover, hDPSCs exerted the immunosuppressive property after IWP‐2 treatment. These results suggest the role of Wnt in inflammatory responses and immunomodulation in dental pulp tissues. [ABSTRACT FROM AUTHOR]

BACKGROUND: Dental pulp stem cells have excellent characteristics of multi-directional differentiation. Among them, osteogenic differentiation potential has a good prospect in bone tissue engineering and regeneration therapy, while inflammatory factors are strongly associated with it. OBJECTIVE: To review the research progress on the bidirectional effects of inflammatory factors and osteogenic differentiation of dental pulp stem cells during bone regeneration. METHODS: In the PubMed, CNKI, and Wanfang databases, the search terms were “dental pulp stem cells, inflammation, osteogenic differentiation, bone regeneration”in Chinese and “dental pulp stem cell*, dpsc*, inflam*, osteogenic differentiation, ossification, osteogenesis, bone formation” in English. Relevant articles published from 2012 to 2022 were retrieved, and 76 articles were finally included for review. RESULTS AND CONCLUSION: (1) As dental mesenchymal stem cells, dental pulp stem cells have well-known multi-directional differentiation characteristics, among which the osteogenic differentiation potential is a research hotspot of bone tissue engineering. (2) Inflammatory factors are strongly associated with bone regeneration mediated by dental pulp stem cells whether they are the microenvironment where cells live, the adjustable immune inflammatory response, or the inflammatory disease with bone tissue defect that needs regeneration. In recent years, there has been no lack of related research. (3) This article selected relevant articles in the past decade, and found that even inflammatory dental pulp stem cells from inflamed pulp tissue still retain certain osteogenic differentiation potential. Further analysis of the bidirectional relationship between inflammatory factors and dental pulp stem cells during bone regeneration found that the effect of inflammatory factors on the osteogenic differentiation of dental pulp stem cells and the immune regulation of dental pulp stem cells on inflammation have both promoting and inhibiting effects. This is mainly related to the type, concentration and time of inflammatory mediators, but the specific mechanisms are not comprehensive. (4) Recently, scholars’ researches focus on exploring the promoting factors that mediate the osteogenic differentiation of dental pulp stem cells in an inflammatory environment, especially the exogenous factors in addition to inflammatory mediators, such as drugs. (5) Some animal experiments and a few clinical trials have verified the therapeutic effect of dental pulp stem cells on inflammatory bone defect diseases especially periodontitis and arthritis by using the anti-inflammatory and osteogenic properties of dental pulp stem cells. (6) At present, there is still a big gap in the research on the mechanism of the bidirectional interaction between inflammatory factors and osteogenic differentiation of dental pulp stem cells during bone regeneration, which needs further investigation and verification in the future. [ABSTRACT FROM AUTHOR]

Background: Conditioned media (CM) derived from mesenchymal stem cells (MSC) is known to induce hair regrowth in androgenic alopecia. Objectives: The objectives of the study were to assess the efficacy and safety of one type of MSC‐CM, the CM derived from dental pulp stem cells obtained from human exfoliated deciduous teeth (SHED‐CM) and to compare the efficacy of SHED‐CM with and without dihydrotestosterone synthesis inhibitor (DHT‐inhibitor). Methods: Eighty‐eight male androgenic alopecia subjects with Hamilton‐Norwood Classification (H‐N C) I–VII were evaluated by trichoscopy to explore which trichoscopic factors statistically correlated with H‐N C. After being screened, 33 subjects received six SHED‐CM treatments at 1‐month intervals. Clinical severity was assessed through global and trichoscopic images from baseline to 9th month. Results: SHED‐CM was effective for 75% of subjects regardless of disease severity, concomitant DHT‐inhibitor use, and age. Adverse effects including pain and small hemorrhages were transient and mild. We also found that clinical hair status evaluated by absolute values of three quantitative trichoscopic factors (maximum hair diameter, vellus hair rate, and multi‐hair follicular unit rate) showed a good correlation with H‐N C stages, and what is more—a scoring system of these three factors can be a possible predictor of SHED‐CM efficacy. Conclusions: We have shown that SHED‐CM provides global and trichoscopic image improvement for androgenic alopecia, regardless of concomitant DHT‐inhibitor use. [ABSTRACT FROM AUTHOR]

BACKGROUND: Revascularization plays an important role in tissue engineering. Dental pulp chamber has its unique anatomy structure, which is surrounded by hard dentin. The blood supply of dental pulp only comes from the narrow apical opening, which makes revascularization more difficult in dental pulp regeneration. OBJECTIVE: To conclude the research advances focusing on the designs of signal molecules, scaffolds and cells in promoting vascularization in dental pulp regeneration. METHODS: We searched the articles on PubMed and CNKI databases with the keywords of “dental pulp regeneration, revascularization, growth factor, material, scaffold, dental pulp stem cell, prevascularization, coculture” in Chinese and English, respectively. Finally, 69 articles met the criteria for review. RESULTS AND CONCLUSION: (1) Vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor are the most studied proangiogenic factors, which promote angiogenesis by promoting the proliferation and migration of endothelial and perivascular cells, the recruitment of stem cells and their differentiation to endothelial cells. (2) To maintain the appropriate concentration of pro-angiogenic factors in the microenvironment, the addition of heparin, laponite and cellulose nanocrystals to the scaffolds can solubilize, encapsulate, adsorb, and covalently cross-link signal molecules, which mimic in vivo storage and release mechanisms. Natural materials including decellularized dental pulp matrix, platelet-rich plasma, and platelet-rich fibrin are rich in bioactive molecules and their structures can protect and control the release of these signal molecules. (3) Different cell sub-populations of dental pulp stem cells have different angiogenic potentials. Moreover, stem cells can be transfected by biological and chemical vectors to improve the cells’ ability to secrete signal molecules and to promote the transformation of stem cells to endothelial cells. Therefore, the angiogenic capacity of transfected cells is significantly enhanced. Co-implantation of stem cells and endothelial cells can also enhance angiogenic capacity. (4) Prevascularization may be the most powerful means to promote rapid vascularization of dental pulp regeneration. In vitro co-culture of endothelial cells and stem cells with a certain ratio can form microtissues containing vascular structures. Microvascular fragments can be obtained by enzymatic digestion of adipose tissue, in which tubular structures and functional cells can promote the development of new blood vessels and anastomosis with host vessels. (5) Current clinical studies on revascularization of dental pulp are limited to dental pulprevascularization, where signal molecules are added while stimulating the formation of blood clots in the root canal and the effects are observed. While other research directions mainly involve in vivo trials in small and large animals, and further clinical trials are still needed to observe regenerative effects, mitigate side effects, and optimize the preparation process. [ABSTRACT FROM AUTHOR]

Dental pulp stem cells (DPSCs) are considered a valuable cell source for regenerative medicine because of their high proliferative potential, multipotency, and availability. We established a new cryopreservation method (NCM) for collecting DPSCs, in which the tissue itself is cryopreserved and DPSCs are collected after thawing. We improved the NCM and developed a new method for collecting and preserving DPSCs more efficiently. Dental pulp tissue was collected from an extracted tooth, divided into two pieces, sandwiched from above and below using cell culture inserts, and cultured. As a result, the cells in the pulp tissue migrated vertically over time and localized near the upper and lower membranes over 2–3 days. With regard to the underlying molecular mechanism, SDF1 was predominantly involved in cell migration. This improved method is valuable and enables the more efficient collection and reliable preservation of DPSCs. It has the potential to procure a large number of DPSCs stably. [ABSTRACT FROM AUTHOR]

BACKGROUND: How to effectively repair and reconstruct critical bone defects has become a difficult problem in clinical medicine. Dental pulp stem cells have certain advantages as transgenic target cells to repair damaged tissues or organs. OBJECTIVE: To investigate the effect of hypoxia-inducible factor-1α on osteogenesis and angiogenesis of dental pulp stem cells in vitro. METHODS: The pulp tissues of healthy and intact bicuspid teeth extracted by orthodontic treatment in patients aged 12 to 18 years were isolated to culture dental pulp stem cells. The hypoxia-inducible factor-1α gene was transfected into dental pulp stem cells in the experimental group. The control group did not do any treatment. The expression of the hypoxia-inducible factor 1α gene was detected by qPCR and the expression of osteogenic and angiogenic factors was detected by western blot assay. RESULTS AND CONCLUSION: (1) Dental pulp stem cells were short spindle-shaped fibroblast-like cells, and the cells grew in colonies. (2) Hypoxia-inducible factor-1α gene was stably transfected into dental pulp stem cells. The expression of the hypoxia-inducible factor-1α gene increased gradually with the extension of time, reached a peak at 14 days, and significantly decreased at 21 days. (3) Compared with the control group, the expression level of angiogenesis-related factors in the experimental group was higher. The protein expression levels of vascular endothelial growth factor, stromal cell-derived factor 1, angiopoietin 2, and placental growth factor were significantly increased at 1 day after gene transfection and reached a peak at 4 days. After that, the expression of angiogenesis-associated protein in the experimental group decreased slightly, but was significantly higher than that in the control group. (4) Compared with the control group, the expression level of osteogenic-related factors in the experimental group was higher. The protein expression levels of human bone morphogenetic protein 2, osteocalcin, and Runt-related transcription factor 2 were significantly increased at 1 day after gene transfection, with the highest protein expression at 4 days. (5) It is concluded that hypoxia-inducible factor-1α can promote the osteogenesis and the expression of angiogenic factors in dental pulp stem cells. [ABSTRACT FROM AUTHOR]

BACKGROUND: Resveratrol is a natural non-flavonoid polyphenol compound. Studies have shown that resveratrol has antioxidant, anti-inflammatory, anti-aging and anti-tumor activities, and promotes the osteogenic differentiation of bone marrow mesenchymal stem cells. However, whether resveratrol can promote the osteogenic differentiation of stem cells from human exfoliated deciduous teeth is even not expounded. OBJECTIVE: To investigate the effects of resveratrol on the proliferation and osteogenic differentiation of stem cells from human exfoliated deciduous teeth. METHODS: Human stem cells from human exfoliated deciduous teeth were isolated and cultured by tissue block method. Osteogenic induced stem cells from human exfoliated deciduous teeth were treated with different concentrations of resveratrol. Cell activity was detected by CCK-8 assay. The number of mineralized nodular cells was detected by alizarin red staining. mRNA expression of osteogenic genes was detected by RT-qPCR and protein expression of Runtrelated transcription factor 2 was detected by western blot assay. RESULTS AND CONCLUSION: (1) CCK-8 assay results showed that after 3 days of treatment, resveratrol at concentrations of (20, 40, 80, and 100 μmol/L) significantly inhibited the proliferation of stem cells from human exfoliated deciduous teeth. Therefore, 1, 5, and 10 μmol/L resveratrol could be used to treat stem cells from human exfoliated deciduous teeth in subsequent experiments to detect their effects on osteogenic differentiation. (2) With 10 μmol/L resveratrol treatment, the number of osteogenic nodules of stem cells from human exfoliated deciduous teeth increased significantly compared with the control group. (3) Alkaline phosphatase, Runt-related transcription factor 2, and osteocalcin mRNA expression levels were increased after 10 μmol/L resveratrol treatment compared with the control group. (4) Runt-related transcription factor 2 protein expression levels of resveratrol treatment groups increased in a concentration-dependent manner compared with the control group. (5) The results indicate that appropriate concentration of resveratrol promotes the proliferation and osteogenic differentiation of stem cells from human exfoliated deciduous teeth. [ABSTRACT FROM AUTHOR]

BACKGROUND: The specific regulatory mechanism underlying osteogenic differentiation of human dental pulp stem cells is still unclear. Therefore, studying the specific mechanism is of great significance for the application of stem cells in tissue engineering. OBJECTIVE: To investigate the role of lentivirus mediated silencing of Smad2 gene in the osteogenic differentiation of human dental pulp stem cells. METHODS: The third generation of human dental pulp stem cells were cultured and divided into blank control group, negative control group, Smad2-shRNA group, and Smad2-shRNA+transforming growth factor-β3 (TGF-β3) group. The mRNA expression of osteogenic related genes Runx2, osteocalcin, Smad2, Smad3, and Smad4 in human dental pulp stem cells was measured by qRT-PCR. The protein expression levels of Runx2, osteocalcin, Smad2/Smad3, p-Smad2/ Smad3, and Smad4 in human dental pulp stem cells were measured by western blot assay. Alizarin red staining was performed in each group on the 7th and 14th days of culture. RESULTS AND CONCLUSION: (1) The mRNA expressions of Runx2, osteocalcin, Smad2, Smad3, and Smad4 in the Smad2-shRNA group were significantly lower than those in the negative control group and blank control group (P < 0.05). The mRNA expressions of osteocalcin, Smad2, Smad3, and Smad4 were significantly increased in the Smad2-shRNA+TGF-β3 group compared with the Smad2-shRNA group (P < 0.05). (2) The protein expressions of Runx2, osteocalcin, and Smad2/Smad3 in the Smad2-shRNA group were significantly lower than those in the negative control group and blank control group (P < 0.05). The protein expressions of RUNX2, osteocalcin, Smad2/Smad3, and Smad4 were significantly increased in the Smad2-shRNA+TGF-β3 group compared with the Smad2- shRNA group (P < 0.05). (3) Culture with conventional medium and transfection with lentiviral vector could not induce the osteogenic differentiation of human dental pulp stem cells, while TGF-β3 could positively regulate the osteogenic differentiation of human dental pulp stem cells. (4) All these findings indicate that theTGF-β/Smad2 signal transduction pathway plays an important role in the osteogenic differentiation of human pulp stem cells. [ABSTRACT FROM AUTHOR]

Objective: Human dental pulp stem cells (hDPSCs) constitute a promising source of stem cells in tissue engineering. However, the molecular mechanism of differentiation in hDPSCs remains largely unclear. MicroRNAs (miRNAs) play crucial roles in lineage‐specific differentiation of stem cells. The present study investigated the function of miRNA‐342‐5p in the odonto/osteogenic differentiation of hDPSCs. Methods: The miRNA array profiling and quantitative real‐time reverse transcriptase‐polymerase chain reaction (qRT‐PCR) revealed the expression of miR‐342‐5p during odonto/osteogenic differentiation of hDPSCs. hDPSCs were treated with miR‐342‐5p mimic and inhibitor to investigate the regulatory roles of miR‐342‐5p in the differentiation of hDPSCs. Moreover, miR‐342‐5p inhibitor and small interference RNA (siRNA) targeting Wnt7b were applied to explore the regulatory mechanism of miR‐342‐5p. Results: Downregulated miR‐342‐5p was observed during odonto/osteogenic differentiation of hDPSCs. The overexpression of miR‐342‐5p inhibited the odonto/osteogenic potential of DPSCs, as indicated by low levels of alkaline phosphatase activity, calcium deposition formation, and odonto/osteogenic differentiation markers, whereas silencing of miR‐342‐5p exhibited the opposite effect. When co‐treated with siRNA targeting Wnt7b and miR‐342‐5p inhibitor in hDPSCs, the odonto/osteogenic potential and activation of Wnt7b/β‐catenin pathway were attenuated. Conclusions: This study showed that miR‐342‐5p inhibits the odonto/osteogenic differentiation of hDPSCs by interfering with Wnt/β‐catenin signaling via targeting Wnt7b. [ABSTRACT FROM AUTHOR]

The odontogenic differentiation of dental pulp stem cells (DPSCs), which is vital for tooth regeneration, was regulated by various functional molecules. In recent years, a growing body of research has shown that miRNAs play a crucial role in the odontogenic differentiation of human dental pulp stem cells (hDPSCs). However, the mechanisms by which miRNAs regulated odontogenic differentiation of hDPSCs remained unclear, and the application of miRNAs in reparative dentin formation in vivo was also rare. In this study, we first discovered that miR-3074-3p had an inhibitory effect on odontogenic differentiation of hDPSCs and antagomiR-3074-3p-conjugated PEI-AuNPs effectively promoted odontogenic differentiation of hDPSCs in vitro. AntagomiR-3074-3p-conjugated PEI-AuNPs was further applied to the rat pulp-capping model and showed the increased formation of restorative dentin. In addition, the results of lentivirus transfection in vitro suggested that FKBP9 acted as the key target of miR-3074-3p in regulating the odontogenic differentiation of hDPSCs. These findings might provide a new strategy and candidate target for dentin restoration and tooth regeneration. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To summarize research progress on forming dental pulp-like tissue from dental pulp stem cells via a co-culture system, as well as provide ideas for stem cell therapy for dental pulp tissue regeneration. METHODS: The first author searched PubMed, CNKI, and Wanfang databases for relevant literature published before May 2022. The English search terms were “dental pulp regeneration, dental pulp stem cell, co-culture, tissue engineering, signaling pathway”, and the Chinese search terms were “dental pulp regeneration, dental pulp stem cells, co-culture, tissue engineering, scaffold, signaling pathway”. Totally 67 articles meeting the criteria were summarized and described. RESULTS AND CONCLUSION: (1) Different combinations of cells are used in co-culture systems to form the main body of the cell and the combined body. (2) Direct co-culture and indirect co-culture are the two types of combination modes at present. Through the intervention of biological scaffold materials and a change in culture conditions, the co-culture outcome can be divided into two-dimensional regenerated tissues and three-dimensional regenerated tissues. (3) Direct co-culture creates an extracellular matrix and microenvironment that facilitates stem cell proliferation and differentiation through intercellular contact. (4) Indirect co-culture addresses the problem of insufficient sources of combined cells and immune rejection between individuals. The biological factors produced by the combined cells can be more easily made into clinical drugs and biological scaffold materials. (5) Though the co-culture system has superior performance in angiogenesis, there are few reports on other structures, and the regeneration of tissue from the co-culture outcome is uncertain. Furthermore, there are limitations to applying newly generated tissue generated by the co-culture system to clinical practice due to tooth anatomical constraints and rejection mechanisms. [ABSTRACT FROM AUTHOR]

Large bone tissue defects present a significant clinical challenge due to the lack of stem cells and an osteogenic microenvironment, leading to fibrotic healing and impaired bone regeneration. Microsphere-based cell-on three-dimensional (3D) culture systems show great promise for constructing osteogenic microtissues. However, the underlying mechanisms require further investigation. In this study, we propose a simple, scalable framework for highly efficient osteogenic microtissue construction, utilizing gelatin methacryloyl (GelMA) microspheres and dental pulp stem cells (DPSCs). The GelMA microspheres provide an extensive, scalable 3D framework for the autonomous adhesion, migration, and proliferation of DPSCs. Within the enormous 3D space created by the microspheres, DPSCs anchor to the microspheres and neighboring cells, inducing intrinsic tensile stress and simulating a mechanical force akin to "rock climbing training". Transcriptomic sequencing results reveal that the 3D spatial and mechanical microenvironment modulates biological processes involved in cell adhesion, extracellular matrix organization, and the positive regulation of cell migration. Further investigations demonstrate that triggering the FAK/YAP pathway mediate mechanical driven differentiation of DPSCs into the osteoblastic lineage in the excellent osteogenic microtissues. Moreover, this simple scalable 3D framework strategy is expected to enable the efficient and large-scale preparation of stem cell-based microtissues. [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND: Dental pulp stem cells have a potential therapeutic value for nervous system diseases due to their wide source, low immunogenicity and excellent ability to differentiate into nervous system cells. OBJECTIVE: To summarize the neurogenic markers of dental pulp stem cells, and provide a research basis for their application in the treatment of clinical nervous system diseases by reviewing the previous studies on the differentiation of dental pulp stem cells into cells of the nervous system. METHODS: Using “dental pulp stem cells, neuro-differentiation, nerve cell markers, nerve” as the Chinese search terms and “dental pulp stem cells, neurodifferentiation, nerve biomarker, nerve” as the English search terms, the computer was used to retrieve articles published on CNKI, Wanfang Data and PubMed databases. According to the inclusion criteria, 85 articles were finally selected for review. RESULTS AND CONCLUSION: (1) Several commonly used neural markers expressed during the differentiation of dental pulp stem cells into neural cells mainly include: nestin, SRY-related HMGbox-containing transcription factor-2, β III tubulin, glial fibrillary acidic protein, microtubule-associated protein 2, S100B, neuron specific enolase, and neuron specific nuclear protein. This article summarizes the characteristics of the above markers, the period of expression and the application of dental pulp stem cells to neural differentiation. (2) Current research shows that to judge whether the differentiation of dental pulp stem cells into neural cells is successful, it is necessary to combine the morphological characteristics and the function of differentiated cells for comprehensive judgment. At the same time, it is difficult to use a single marker to specifically identify a single cell lineage. Therefore, it is necessary to analyze more markers applied to the analysis of one cell type. (3) From the aspects of growth factors, signal pathways, and biological brackets, the method of differentiation of pulp stem cells to neuronal cells is introduced to provide theoretical reference in inducing dental pulp stem cells to neural differentiation. [ABSTRACT FROM AUTHOR]

Aim: Calcium hydroxide is the gold standard material for pulp capping and has been widely used in clinical dentistry. Calcium hydroxide promotes proliferation, migration and osteogenic differentiation of dental pulp stem cells (DPSCs). However, the underlying mechanism is not clear. Our study investigated the role of Wnt/β‐catenin pathway in calcium hydroxide‐induced proliferation, migration, osteogenic differentiation and mineralization of human DPSCs. Methodology: Protein and gene expression was detected by western blot (WB), immunofluorescence staining and quantitative real‐time PCR (qPCR). Cell viability was analysed using the Cell Counting Kit‐8 (CCK‐8) assay. Wound‐healing assay was used to analyse cell migration. The expression of alkaline phosphatase (ALP) was detected using ALP staining. Mineralization was analysed by alizarin red staining. Results: Calcium hydroxide increased the protein expression of phosphorylated‐GSK3β/GSK3β, β‐catenin and the gene expression of LEF‐1. Inhibition of Wnt/β‐catenin abolished calcium hydroxide‐induced proliferation and migration of DPSCs in 24 h. However, incubation with calcium hydroxide for 7 days and 14 days reduced Wnt/β‐catenin signalling. Inhibition of Wnt/β‐catenin promoted calcium hydroxide‐induced osteogenic differentiation and mineralization in DPSCs. Conclusion: Wnt/β‐catenin pathway plays a dual role in calcium hydroxide‐regulated DPSC behaviour. Incubation with calcium hydroxide promoted rapid proliferation and migration of DPSCs, while prolonged incubation negatively regulated osteogenic differentiation and mineralization. [ABSTRACT FROM AUTHOR]

Therefore, this study aimed to investigate the emergence of macrophages in dental pulp tissue after direct pulp capping, and the effect of M2 macrophages on the odontoblastic differentiation of DPSC clones. In the present study, the number of M1 macrophages increased at the pulp exposure site soon after injury, followed by an increase in the M2 macrophages as M1 macrophages disappeared and the reparative dentin formation started. Keywords: macrophage; direct pulp capping; dental pulp stem cell; reparative dentin formation; odontoblastic differentiation EN macrophage direct pulp capping dental pulp stem cell reparative dentin formation odontoblastic differentiation 1812 11 11/17/22 20221101 NES 221101 1. In the present study, M1 macrophages increased soon after the dental pulp exposure and decreased as the M2 macrophages started to emerge, indicating an inflammatory response at the early phase of the wound healing by the M1 macrophages and their proper polarization to the M2 macrophages. [Extracted from the article]

BACKGROUND: Revascularization plays an important role in tissue engineering. Dental pulp chamber has its unique anatomy structure, which is surrounded by hard dentin. The blood supply of dental pulp only comes from the narrow apical opening, which makes revascularization more difficult in dental pulp regeneration. OBJECTIVE: To conclude the research advances focusing on the designs of signal molecules, scaffolds and cells in promoting vascularization in dental pulp regeneration.METHODS: We searched the articles on PubMed and CNKI databases with the keywords of “dental pulp regeneration, revascularization, growth factor, material, scaffold, dental pulp stem cell, prevascularization, coculture” in Chinese and English, respectively. Finally, 69 articles met the criteria for review. RESULTS AND CONCLUSION:（1） Vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor are the most studied proangiogenic factors, which promote angiogenesis by promoting the proliferation and migration of endothelial and perivascular cells, the recruitment of stem cells and their differentiation to endothelial cells.（2） To maintain the appropriate concentration of pro-angiogenic factors in the microenvironment, the addition of heparin, laponite and cellulose nanocrystals to the scaffolds can solubilize, encapsulate, adsorb, and covalently cross-link signal molecules, which mimic in vivo storage and release mechanisms. Natural materials including decellularized dental pulp matrix, platelet-rich plasma, and platelet-rich fibrin are rich in bioactive molecules and their structures can protect and control the release of these signal molecules.（3） Different cell sub-populations of dental pulp stem cells have different angiogenic potentials. Moreover, stem cells can be transfected by biological and chemical vectors to improve the cells’ ability to secrete signal molecules and to promote the transformation of stem cells to endothelial cells. Therefore, the angiogenic capacity of transfected cells is significantly enhanced. Co-implantation of stem cells and endothelial cells can also enhance angiogenic capacity.（4） Prevascularization may be the most powerful means to promote rapid vascularization of dental pulp regeneration. In vitro co-culture of endothelial cells and stem cells with a certain ratio can form microtissues containing vascular structures. Microvascular fragments can be obtained by enzymatic digestion of adipose tissue, in which tubular structures and functional cells can promote the development of new blood vessels and anastomosis with host vessels.（5） Current clinical studies on revascularization of dental pulp are limited to dental pulprevascularization, where signal molecules are added while stimulating the formation of blood clots in the root canal and the effects are observed. While other research directions mainly involve in vivo trials in small and large animals, and further clinical trials are still needed to observe regenerative effects, mitigate side effects, and optimize the preparation process. [ABSTRACT FROM AUTHOR]

Background: Bone has important functions in the body. Several researchers have reported that the polysaccharides and lipopolysaccharide derived from microbes can promote osteogenic differentiation of stem cells. Enterococcus faecium, a lactic acid bacterium (LAB), produces several bioactive metabolites and has been widely applied in the food and nutraceutical industries. The exopolysaccharide (EPS) from LAB has also been extensively examined for its postbiotic effects and for its in vivo and in vitro functionalities. However, studies on promoting bone differentiation using polysaccharides from LAB are lacking. Therefore, the purpose of this study was to investigate the effect of E. faecium L15 extract and EPS on osteogenic differentiation of human dental pulp stem cells (hDPSCs) and to identify the underlying mechanisms. Methods: hDPSCs were obtained from dental pulp tissue, and L15 extract and EPS were isolated from L15. Gene and protein expression of the osteogenic differentiation markers were analyzed with qPCR and western blotting and the possible signaling pathways were also investigated using western blotting. Osteogenic differentiation potential was examined by alkaline phosphatase (ALP) staining and alizarin red s (ARS) staining. In addition, osteogenic differentiation potential of L15 EPS was explored in ex vivo culture of neonate murine calvaria. Results: The calcium deposition and ALP activity were enhanced by addition of L15 extract or EPS. The expression levels of RUNX2, ALP, and COL1A1 mRNA and the protein expression levels of RUNX2, ALP, and BMP4 were increased in hDPSCs treated with the L15 extract or EPS. The L15 EPS treatment enhanced phosphorylation of the p38 mitogen-activated protein kinase (MAPK). The L15 EPS-induced increases in RUNX2, ALP, and BMP4 expression were suppressed by the p38 MAPK inhibitor SB203580. The promoting effect of L15 EPS on osteogenic differentiation was not only seen in hDPSCs, but also in osteoblast precursors. ALP activity and the expression of RUNX2, ALP, and COL1A1 increased in the L15 EPS-treated osteoblast precursors. In addition, L15 EPS increased bone thickness of neonate murine calvaria in ex vivo culture. Conclusions: The stimulatory effect of L15 extract and EPS on osteogenic differentiation occurred through the p38 MAPK pathway, and L15 EPS enhanced new bone formation in neonate murine calvaria. These data suggest that L15 EPS has therapeutic potential applicable to bone regeneration. [ABSTRACT FROM AUTHOR]

Objective: The study aims to evaluate the effect of bone morphogenetic protein-2 (BMP-2) and transforming growth factor-beta 1 (TGF-β1) co-stimulation on odontogenic differentiation of human dental pulp stem cells (hDPSCs). Materials and methods: The viability/proliferation of hDPSCs treated with BMP-2 (group B), TGF-β1 (group T), or BMP-2/TGF-β1 (group BT) were evaluated. The experiments on odontogenic differentiation were done for 14 days. The following subgroups were added to investigate the effect of co-stimulation with different timing: subgroup B1, TGF-β1 co-stimulation in the first week; subgroup B2, TGF-β1 co-stimulation in the second week; subgroup T1, BMP-2 co-stimulation in the first week; and subgroup T2, BMP-2 co-stimulation in the second week. The mineralization was assessed using alizarin red staining. The expression of following genes was assessed using quantitative real-time polymerase chain reaction: dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP1), osteopontin (OPN), and alkaline phosphatase. Results: All groups showed viability similar to the control group (P >.05). The greater mineralization was detected in B groups on day 14. The expressions of DSPP, DMP-1, and OPN increased on day 14 (P <.05). In the combination groups, the higher expressions of DSPP and DMP-1 were observed in subgroups B1 and B2 than groups B and T (P <.05). Conclusions: BMP-2 was the key in odontogenic differentiation of hDPSCs, which was further enhanced by co-stimulation with TGF-β1. Continuous stimulation with TGFβ-1 did not improve the differentiation of hDPSCs. Clinical relevance: Combined use of the BMP-2 and TGFβ-1 at the specific sequence can provide a tissue engineering approach for the future guided dentin regeneration. [ABSTRACT FROM AUTHOR]

Background: Extracellular vesicles (EVs) play a key role in constructing a microenvironment that favors the differentiation of stem cells. The present work aimed to determine the molecular mechanisms by which EV derived from inflammatory dental pulp stem cell (iDPSC-EV) influence periodontal ligament stem cells (PDLSCs) and provide a potential strategy for bone and dental pulp regeneration.Methods: The osteogenic and odontogenic differentiation was assessed by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S (ARS) staining, and immunofluorescence staining. To detect proliferation, the Cell Counting Kit-8 (CCK-8) assay, and flow cytometry analysis were used. EVs were isolated by the Exoperfect kit and ultrafiltration and characterized by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot. The expression profile of miRNAs in EVs was studied using miRNA sequence and bioinformatics, and one of the upregulated miRNAs was evaluated on PDLSCs.Results: The inflammatory microenvironment stimulated osteogenic and odontogenic differentiation of DPSCs and iDPSC-EV behaved alike on PDLSCs. MiR-758-5p was upregulated in iDPSC-EV and was demonstrated to play a significant role in the osteogenic and odontogenic commitment of PDLSCs. A dual-luciferase reporter assay confirmed the binding site between miR-758-5p and limb development membrane protein 1 (LMBR1). The knockdown of LMBR1 also enhanced the above potential. Mechanically, bone morphogenetic protein (BMP) signaling was activated.Conclusions: EVs from the inflammatory microenvironment enhanced the osteogenic and odontogenic differentiation of PDLSCs partly by shuttering LMBR1-targeting miR-758-5p via BMP signaling. [ABSTRACT FROM AUTHOR]

The osteogenic differentiation of mesenchymal stem cells (MSCs) is strongly related with the inflammatory microenvironment. The ability of osteogenic differentiation of MSCs is vital for the bone tissue engineering. Interleukin (IL)-10, a well-known anti-inflammatory factor, plays a key role in tissue repair. Dental pulp stem cells (DPSCs), with the advantage of convenience of extraction, are suitable for the bone tissue engineering. Therefore, it is meaning to explore the effects of IL-10 on the osteogenic differentiation of DPSCs. The proliferation activity of DPSCs were evaluated by MTS assay (CellTiter 96® Aqueous One Solution Cell Proliferation Assay [Promega]) and real-time polymerase chain reaction (RT-PCR). The osteogenic differentiation of DPSCs were determined by Alizarin Red staining, RT-PCR, and alkaline phosphatase activity test. The glucose metabolism was detected by Mito Stress test and glycolysis assay. IL-10 (10 or 20 nM) could enhance the osteogenic differentiation of DPSCs and promoted the metabolic switch from glycolysis to oxidative phosphorylation (OXPHOS), whereas IL-10 (5 and 50 nM) has no obvious effects on the osteogenic differentiation of DPSCs. The OXPHOS inhibitor restrained the promotion of osteogenic differentiation induced by IL-10. These findings show that IL-10 can promote the osteogenesis of DPSCs through the activation of OXPHOS, which provides a potential way for enhancing the osteogenic differentiation of DPSCs in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Cerebral ischemia-reperfusion injury (I/RI) is one of the principal pathogenic factors in the poor prognosis of ischemic stroke, for which current therapeutic options to enhance neurological recovery are notably insufficient. Dental pulp stem cell-derived extracellular vesicles (DPSC-EVs) have promising prospects in stroke treatment and the specific underlying mechanisms have yet to be fully elucidated. The present study observed that DPSC-EVs ameliorated the degree of cerebral edema and infarct volume by reducing the apoptosis of neurons. Furthermore, the miRNA sequencing and functional enrichment analysis identified that miR-877–3p as a key component in DPSC-EVs, contributing to neuroprotection and anti-apoptotic effects. Following target prediction and dual-luciferase assay indicated that miR-877–3p interacted with Bcl-2-associated transcription factor (Bclaf1) to play a function. The miR-877–3p inhibitor or Bclaf1 overexpression reversed the neuroprotective effects of DPSC-EVs. The findings reveal a novel therapeutic pathway where miR-877–3p, transferred via DPSC-EVs, confers neuroprotection against cerebral I/RI, highlighting its potential in promoting neuronal survival and recovery post-ischemia. [Display omitted] [ABSTRACT FROM AUTHOR]

Dental pulp stem cells (DPSCs) have been recommended as promising candidate for cell-based therapeutic applications due to high potentials in tissue repair/regeneration and modulation of immune responses. The gene expression change strategy by natural plant enhancers is an available opportunity to improve the stemness properties of these cells. The objective of this research was the evaluation of Crocin effects (saffron plant's bioactive compound) on immunoregulation and tissue regeneration-related biomarkers expression in human DPSCs. Based on the results of cell viability assay, application of 400 μM and lower concentrations of Crocin had no toxic effects on DPSCs; however, the time-dependent cytotoxic effects were observed at higher concentrations. This study, probably for the first time, detected the surface expression of CD200 in DPSCs with a slight time-dependent upward trend and reported that treatment with Crocin could increase expression of this macromolecule up to many times over. Also, it revealed that this carotenoid significantly led to the time-dependent upregulation of dentin sialophosphoprotein, vascular endothelial growth factor A, human leukocyte antigen-G5, and signal transducer and activator of transcription-3 messenger ribonucleic acids (mRNAs); however, this significant upregulation for STAT3 occurred, followed by a remarkable reduction. The results of this study indicated that cell treatment with Crocin may be effective in improving the stemness capacities of DPSCs. Therefore, the study provided basis for more insights into the biological effects of Crocin on DPSCs that it may aid in the future improvement of mesenchymal stem cell-based therapies. [ABSTRACT FROM AUTHOR]

Aim: To identify odontogenesis‐promoting compounds and examine the molecular mechanism underlying enhanced odontoblast differentiation and tooth formation. Methodology: Five different nymphaeols, nymphaeol B (NB), isonymphaeol B (INB), nymphaeol A (NA), 3'‐geranyl‐naringenin (GN) and nymphaeol C (NC) were isolated from the fruit of Macaranga tanarius. The cytotoxic effect of nymphaeols on human DPSCs was observed using a 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay. The effect of nymphaeols on odontoblast differentiation was analysed with Alizarin Red S staining and odontoblast marker expression was assessed using real‐time polymerase chain reaction and Western blot analysis. The molecular mechanism was investigated with Western blot analysis. In order to examine the effect of INB on dentine formation in the developing tooth germ, INB‐soaked beads were placed under the tooth bud explants in the collagen gel; thereafter, the tooth bud explant‐bead complexes were implanted into the sub‐renal capsules for 3 weeks. Tooth root formation was analysed using micro‐computed tomography and histological analysis. Data are presented as mean ± standard error (SEM) values of three independent experiments, and results are compared using a two‐tailed Student's t‐test. The data were considered to have statistical significance when the P‐value was less than 0.05. Results: Three of the compounds, NB, INB, and GN, did not exert a cytotoxic effect on human DPSCs. However, INB was most effective in promoting the deposition of calcium minerals in vitro (P < 0.001) and induced the expression of odontogenic marker genes (P < 0.05). Moreover, this compound strongly induced the phosphorylation of mitogen‐activated protein (MAP) kinases and protein kinase B (AKT) (P < 0.05). The inhibition of p38 MAP, c‐Jun N‐terminal kinase (JNK), and AKT substantially suppressed the INB‐induced odontoblast differentiation (P < 0.001). In addition, isonymphaeol B significantly induced the formation of dentine and elongation of the tooth root in vivo (P < 0.05). Conclusions: Prenylflavonoids, including INB, exerted stimulatory effects on odontoblast differentiation and tooth root and dentine formation via the MAP kinase and AKT signalling pathways. These results suggest that nymphaeols could stimulate the repair processes for dentine defects or injuries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Since the application of transcriptome sequencing technology has made remarkable achievements in the research of melanoma and breast cancer, transcriptome sequencing technology has become a hot research method in scientific research and widely used in the field of stomatology. OBJECTIVE: To review the development of transcriptome sequencing technology and its application in various disciplines of stomatology through searching, screening and reading literature. METHODS: A search of CNKI, CBM and PubMed was performed for relevant literature published from 2015 through 2020. The search terms were “transcriptome, sequencing technology, RNA-seq, microarray, oral cancers, OSCC, periodontal, caries, pulp disease, tooth development, DPSCs, PDLSCs, orthodontics, implant” in English and Chinese, respectively. According to the inclusion and exclusion criteria, 72 literatures were included to review the development of transcriptome sequencing technology and its application in the field of stomatology. RESULTS AND CONCLUSION: In the development of transcriptome sequencing technology, RNA-seq technology has the greatest advantage in scientific research, because of its high accuracy, high throughput and low price. In the field of stomatology, this technology has been used in the research of oral squamous cell carcinoma, periodontitis, dental pulp disease, tooth regeneration, orthodontics and dental implantation, and has achieved some achievements. However, the current research on the same kind of disease does not reflect the relationship between the various studies, and the research content is limited. It is believed that more discoveries can be yielded in stomatology by exploring the relationship between different studies and expanding the research content. [ABSTRACT FROM AUTHOR]

Background: Sjögren's syndrome (SS) is a chronic autoimmune disease primarily characterized by inflammation in the salivary and lacrimal glands. Activated T cells contribute to disease pathogenesis by producing proinflammatory cytokines, which leads to a positive feedback loop establishment. The study aimed to evaluate the effects of secreted factors derived from dental pulp stem cells (DPSCs) or bone marrow mesenchymal stem cells (BMMSCs) on hyposalivation in SS and to investigate the mechanism involved. Methods: Eighty percent confluent stem cells were replenished with serum-free Dulbecco's modified Eagle's medium and incubated for 48 h; following which, conditioned media from DPSCs (DPSC-CM) and BMMSCs (BMMSC-CM) were collected. Cytokine array analysis was performed to assess the types of cytokines present in the media. Flow cytometric analysis was performed to evaluate the number of activated T cells cultured in DPSC-CM or BMMSC-CM. Subsequently, DPSC-CM or BMMSC-CM was administered to an SS mouse model. The mice were categorized into the following groups (n = 6 each): non-treatment, Dulbecco's modified Eagle's medium (−), BMMSC-CM, and DPSC-CM. Histological analysis of the salivary glands was performed. The gene and protein expression levels of cytokines associated with T helper subsets in the submandibular glands (SMGs) were evaluated. Results: DPSC-CM contained more secreted factors with tissue-regenerating mechanisms, such as cell proliferation, anti-inflammatory effects, and immunomodulatory effects. DPSC-CM was more effective in suppressing the activated T cells than other groups in the flow cytometric analysis. The stimulated salivary flow rate increased in SS mice with DPSC-CM compared with that in the other groups. In addition, the number of inflammation sites in SMGs of the mice administered with DPSC-CM was lower than that in the other groups. The expression levels of interleukin (Il)-10 and transforming growth factor-β1 were upregulated in the DPSC-CM group, whereas those of Il-4 and Il-17a were downregulated. The DPSC-CM-administered group presented with a significantly increased percentage of regulatory T (Treg) cells and a significantly decreased percentage of type 17 Th (Th17) cells compared with the other groups. Conclusions: These results indicated that DPSC-CM ameliorated SS by promoting Treg cell differentiation and inhibiting Th17 cell differentiation in the mouse spleen. [ABSTRACT FROM AUTHOR]

LIM homeobox 8 (LHX8) is expressed during embryonic development of craniofacial tissues, including bone and teeth. In a previous study, the overexpression of LHX8 inhibited osteodifferentiation of human dental pulp stem cells (DPSCs). In this study, a cDNA microarray analysis was performed to reveal the molecular changes which occur in response to LHX8 overexpression in DPSCs and discover possible targets for an osteoinductive agent. There were 345 differentially expressed genes (DEGs) in response to osteoinductive signaling and 53 DEGs in response to LHX8 overexpression and osteoinductive signaling, respectively. Thirty-eight genes were common in both conditions, and among these, genes upregulated in LHX8 DPSCs but downregulated in osteodifferentiated DPSCs were chosen. Five of them had commercial inhibitors available. Among the tested inhibitors, ML323, which target DNA-binding protein inhibitor ID-1, promoted osteodifferentiation of DPSCs. In conclusion, inhibition of ID-1 led to increased osteogenesis of human DPSCs. • LHX8 overexpression attenuates osteogenesis; however, it does not affect the proliferation, migration, and angiogenesis. • Using an hDPSC model overexpressing anti-osteogenic gene LHX8 , genes that may have a role in osteogenesis were selected. • Screening of chemical inhibitors for their protein products resulted in the discovery of a potential osteogenic agent, ML323. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mechanical stimulation plays a necessary regulatory role in developing and repairing many organs and tissues in the human body. Except for biochemical factors, mechanical factors are considered as key regulatory factors that affect the behavior and function of dental pulp stem cells. OBJECTIVE: To review the role and effect of cellular mechanical stimulation on the biological behavior of dental pulp stem cells. METHODS: PubMed, Embase, Medline and CNKI databases were searched for relevant literatures using the keywords of “human dental pulp stem cells (hDPSCs), mechanical strain, mechanical stretch, mechanical tension, shear stress, cell proliferation, osteogenesis differentiation” in English and Chinese, respectively. Fifty-six articles were finally eligible for review, which were closely related to the proliferation and differentiation of dental pulp stem cells under cellular mechanical stimulation. RESULTS AND CONCLUSION: Cellular mechanical stimulation is an important biological factor affecting cell proliferation, differentiation, apoptosis and protein expression. Dental pulp stem cells are mesenchymal stem cells derived from the dental pulp tissue, and their biological behaviors are also affected by cellular mechanical stimulation. Cellular mechanical stimulation is involved in the proliferation, odontogenesis/osteogenesis of dental pulp stem cells. When the dentin is subjected to fluid flow forces, mechanoreceptors are activated to regulate and maintain the integrity of tooth structure. Signal pathways that mediate the biological behavior of dental pulp stem cells include MAPK, Wnt, Akt, BMP-7, and Nrf2/HO-1, which are involved in promoting and inhibiting the proliferation and odontogenesis/osteogenesis of dental pulp stem cells to varying degrees. [ABSTRACT FROM AUTHOR]

Supernumerary tooth (ST) may arise from uncertain developmental abnormalities or underlying genetic causes, and the extraction at the early age is recommended. Dental pulp stem cells (DPSCs) are the valuable resource for the regeneration of tooth and related craniofacial structures. DPSCs isolated from ST (sDPSCs) have not been fully characterized despite the potential in the applications. The objectives of this study are the efficient isolation of sDPSCs and the analysis of the properties as stem cells. sDPSCs were established by hammer-cracking and separation of the intact pulp from ST. sDPSCs in the culture were examined by light microscope and flow cytometer for the morphology and the surface marker expression. sDPSCs exhibited the cellular morphology of typical mesenchymal stem cells and expressed CD44, CD73, CD90, CD105 and CD166, but not CD14, CD34 or CD45. sDPSCs showed the differentiation potential toward osteogenic, chondrogenic and adipogenic lineages. During osteogenic differentiation, the stimulation by Oncostatin M enhanced the differentiation and significantly increased the expression of genes involved in the hard tissue repair, such as BMP2, BMP4, BMP6 and RUNX2. sDPSCs can be effectively derived from ST and displays the characteristics of mesenchymal stem cells in the maintenance and the differentiation. sDPSCs satisfies the quality as DPSCs thus provide the valuable resource to the regenerative therapy. • Efficient and stable isolation of dental pulp stem cells from supernumerary teeth. • Supernumerary tooth dental pulp stem cells exhibit characteristics as mesenchymal stem cells. • Oncostatin M stimulation accelerates the osteogenic differentiation of supernumerary tooth dental pulp stem cells. [ABSTRACT FROM AUTHOR]

Cell size is one of the deciding factors in tissue engineering for successful tissue regeneration through determining outcome of both cell delivery and cell attachment. This study aimed to determine the effect of different in-vitro culture condition on mammalian stem cell size. The pulp tissue extracted from mice incisors were digested using collagenase 1A. The resulting mice dental pulp cells (mDPC) suspensions were cultured in monolayer and hanging drop in-vitro culture. The human peripheral blood mononucleated cells (hPBC) isolated from peripheral blood using Ficoll-Paque™ Plus and cultured in complete media. After 7 days, the resulting suspension type hPBC were cultured separately in suspension in-vitro culture. The cell size for 30 days was measured using CellB software. The monolayer culture exerted largest changes with an increase (89.12±17.722 %) to the initial cell size of mDPC. Meanwhile, hanging drop culture resulted in smaller changes with a decrease (-25.84±6.706 %) to the initial cell size. While, the suspension culture causes least change with a decrease (-7.60 ± 4.302 %) to the initial size of hPBC in 30 days. All the in-vitro culture conditions exerted their largest changes on the cells at first 7 days compared to the rest of the culture period. The in-vitro viability of mDPC were determined through MTT assay and showed significant (p<0.05) increase in viable cells on day 21 compared to day 0. The mDPSC size attain stability in monolayer and hanging drop culture by day 14 and day 21, respectively. The size of mDPSC in monolayer and hanging drop culture are 13.63±1.613 µm and 10.45±1.145 µm, respectively. mDPSC size in both culture conditions does not show any differences with increasing culturing period and therefore, could be used for further applications. [ABSTRACT FROM AUTHOR]

Dental pulp stem cells (DPSCs) have a high capacity for differentiation and the ability to regenerate a dentin/pulp-like complex. Numerous studies have provided evidence of DPSCs' differentiation capacity, such as in neurogenesis, adipogenesis, osteogenesis, chondrogenesis, angiogenesis, and dentinogenesis. The molecular mechanisms and functions of DPSCs' differentiation process are affected by growth factors and scaffolds. For example, growth factors such as basic fibroblast growth factor (bFGF), transforming growth factor-β (TGF-β), nerve growth factor (NGF), platelet-derived growth factor (PDGF), and bone morphogenic proteins (BMPs) influence DPSC fate, including in differentiation, cell proliferation, and wound healing. In addition, several types of scaffolds, such as collagen, hydrogel, decellularized bioscaffold, and nanofibrous spongy microspheres, have been used to characterize DPSC cellular attachment, migration, proliferation, differentiation, and functions. An appropriate combination of growth factors and scaffolds can enhance the differentiation capacity of DPSCs, in terms of optimizing not only dental-related expression but also dental pulp morphology. For a cell-based clinical approach, focus has been placed on the tissue engineering triad [cells/bioactive molecules (growth factors)/scaffolds] to characterize DPSCs. It is clear that a deep understanding of the mechanisms of stem cells, including their aging, self-renewal, microenvironmental homeostasis, and differentiation correlated with cell activity, the energy for which is provided from mitochondria, should provide new approaches for DPSC research and therapeutics. Mitochondrial functions and dynamics are related to the direction of stem cell differentiation, including glycolysis, oxidative phosphorylation, mitochondrial metabolism, mitochondrial transcription factor A (TFAM), mitochondrial elongation, and mitochondrial fusion and fission proteins. This review summarizes the effects of major growth factors and scaffolds for regenerating dentin/pulp-like complexes, as well as elucidating mitochondrial properties of DPSCs for the development of advanced applications research. [ABSTRACT FROM AUTHOR]

Dental pulp stem cells (DPSCs) are reported to be enriched in stem/progenitor cells, however to the best of our knowledge they have yet to be well documented and characterized. In the present study, in order to characterize DPSCs and the effect of microRNAs (miRs/miRNAs) on DPSC properties, a miRNA array was performed between dental periodontal ligament cells (DPLCs) and DPSCs. The results revealed that miR-224-5p (miR-224) was highly expressed in the DPSCs compared with that in the DPLCs. The transfection of DPSCs with an miR-224 inhibitor impaired cell viability. In addition, miR-224 inhibition significantly promoted cell apoptosis in DPSCscompared with the NC group. In silico analysis and a dual-luciferase reporter assay demonstrated that miR-224 targets the 3′-untranslated region of the Rac family small GTPase 1 (Rac1) gene. miR-224 downregulation resulted in the increased expression of Rac1 in DPSCs compared with DPLCs. Furthermore, miR-224 inhibition caused augmented mitogen-activated protein kinase 8, caspase-3, caspase-9 and Fas ligand expression in DPSC, which may be recovered by Rac1 silencing with transfection with short hairpin RNA-Rac1. Furthermore, Annexin V-fluorescein isothiocyanate/propidium iodide flow cytometry indicated that the silencing of Rac1 restored the pro-apoptotic DPSC cell number with miR-224 transfection. Therefore, the results of the present study suggested miR-224 in DPSC serves an important function in protecting cells against apoptosis by downregulating Rac1 expression, and also identified miR-224 as a novel miRNA in regulating the features of DPSC. [ABSTRACT FROM AUTHOR]

As human-origin cells, human dental pulp stem cells (hDPSCs) are thought to be potentially useful for biological and medical experiments. They are easily obtained from lost primary teeth or extracted wisdom teeth, and they are mesenchymal stem cells that are known to differentiate into osteoblasts, chondrocytes, and adipocytes. Although hDPSCs originate from neural crest cells, it is difficult to induce hDPSCs to differentiate into neuron-like cells. To facilitate their differentiation into neuron-like cells, we evaluated various differentiation conditions. Activation of K+ channels is thought to regulate the intracellular Ca2+ concentration, allowing for manipulation of the cell cycle to induce the differentiation of hDPSCs. Therefore, in addition to a conventional neural cell differentiation protocol, we activated K+ channels in hDPSCs. Immunocytochemistry and real-time PCR revealed that applying a combination of 3 stimuli (high K+ solution, epigenetic reprogramming solution, and neural differentiation solution) to hDPSCs increased their expression of neuronal markers, such as ß3-tubulin, postsynaptic density protein 95, and nestin within 5 days, which led to their rapid differentiation into neuron-like cells. Our findings indicate that epigenetic reprogramming along with cell cycle regulation by stimulation with high K+ accelerated the differentiation of hDPSCs into neuronlike cells. Therefore, hDPSCs can be used in various ways as neuron-like cells by manipulating their cell cycle. [ABSTRACT FROM AUTHOR]

In this study, we fabricated a silk scaffold containing nano-hydroxyapatite (nano-HAp) for bone tissue engineering applications. The sericin-extracted silk scaffolds were coated with 0.30, 0.15, and 0.03 g of nano-HAp. The scaffolds were soaked in a 1% type I atelocollagen solution and lyophilized. Scaffolds were crosslinked with 0.02% carbodiimide and lyophilized for 48 h, followed by sterilization with γ-irradiation at 10 kGy. The scaffold properties were investigated by energy-dispersive X-ray spectroscopy and atomic force microscope. A typical spectrum of the inorganic crust and the electron diffraction patterns revealed peaks for calcium, phosphorus, and oxygen atoms. Root mean square values of the control and experimental group surfaces were 5.60 and 40.32 nm. The width of nano-HAp was in the approximate range 100–150 nm, and the height was approximately 350 nm. Dental pulp cells were seeded at a density of 2.8 × 104 cells/cm2 and cultured for 3 weeks in a growth medium. The cells were then cultured for 4 weeks in differentiation medium and were transplanted into a nude mouse. The biopsy was processed at 8 weeks. The use of 0.15 g of nano-HAp led to the greatest collagen type III, fibronectin, osteocalcin, osteopontin, osteonectin, osteoprotegerin, and BMP-2 mRNA levels in vitro after 4 weeks in differentiation medium. Western blotting analysis to elucidate signaling pathways was performed. β-Catenin, phosphorylated-ERK, p38 phosphorylation most increased when 0.15 g of nano-HAp was used compared with the control group. In the histological comparison, osteocalcin and osteopontin synthesis were higher for the silk scaffold that contained 0.15 g of nano-HAp. Among the scaffolds, samples containing 0.15 g of nano-HAp were the most effective for osteogenesis. Therefore, this will be a suitable substrate as a biomaterial for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Dental caries and trauma, particularly in childhood, are among the most prevalent teeth problems, which result in the creation of cavities and probably tooth loss. Thus, novel regenerative approaches with high efficiency and less toxicity are required. Stem cell therapy along with the implementation of scaffolds has provided excellent opportunities in the regeneration of teeth structure. Hyaluronic acid (HA) hydrogels have enticed great attention in the field of regenerative medicine. The unique chemical and structural properties of HA and its derivatives have enabled their application in tissue engineering. Several factors such as the location and type of the lesion, teeth age, the type of capping materials determine the success rate of pulp therapy. HA hydrogels have been considered as biocompatible and safe scaffold supports in human dental cell therapies. Unlabelled Image [ABSTRACT FROM AUTHOR]

Aims/Introduction: Dental pulp stem cells (DPSCs) can be easily obtained from teeth for general orthodontic reasons. We have previously reported the therapeutic effects of DPSC transplantation for diabetic polyneuropathy. As abundant secretomes from DPSCs are considered to play a central role in the improvement of diabetic polyneuropathy, we investigated whether direct injection of DPSC‐conditioned media (DPSC‐CM) into hindlimb skeletal muscles ameliorates diabetic polyneuropathy in diabetic rats. Materials and Methods: DPSCs were isolated from the dental pulp of Sprague–Dawley rats. Eight weeks after the induction of diabetes, DPSC‐CM was injected into the unilateral hindlimb skeletal muscles in both normal and diabetic rats. The effects of DPSC‐CM on diabetic polyneuropathy were assessed 4 weeks after DPSC‐CM injection. To confirm the angiogenic effect of DPSC‐CM, the effect of DPSC‐CM on cultured human umbilical vascular endothelial cell proliferation was investigated. Results: The administration of DPSC‐CM into the hindlimb skeletal muscles significantly ameliorated sciatic motor/sensory nerve conduction velocity, sciatic nerve blood flow and intraepidermal nerve fiber density in the footpads of diabetic rats. We also showed that DPSC‐CM injection significantly increased the capillary density of the skeletal muscles, and suppressed pro‐inflammatory reactions in the sciatic nerves of diabetic rats. Furthermore, an in vitro study showed that DPSC‐CM significantly increased the proliferation of umbilical vascular endothelial cells. Conclusions: We showed that DPSC‐CM injection into hindlimb skeletal muscles has a therapeutic effect on diabetic polyneuropathy through neuroprotective, angiogenic and anti‐inflammatory actions. DPSC‐CM could be a novel cell‐free regenerative medicine treatment for diabetic polyneuropathy. [ABSTRACT FROM AUTHOR]

Summary: Pulpitis suppressed the level of let‐7c‐5p that promotes osteogenesis and bone formation by repressing HMGA2. In the current study, the function of let‐7c‐5p in the inflammation and osteogenesis in dental pulp stem cells (DPSCs) was explored. The level of let‐7c‐5p in DPSCs was up‐regulated, and the cells were subjected to lipopolysaccharide (LPS) to induce inflammation. The effect of let‐7c‐5p on cell proliferation potential, osteogenic differentiation potential, and activity of HMGA2/PI3K/Akt pathway was detected. The administration of LPS suppressed the cell proliferation of DPSCs and suppressed calcium deposition, activity of alkaline phosphatase (ALP), and levels of OCN, OPN, OSX, MSX2, and RUNX2 in inflamed DPSCs. The impaired osteogenic differentiation of inflamed DPSCs was associated with the increased levels of HMGA2, p‐PI3K, and p‐Akt. In let‐7c‐5p‐overexpressed inflamed DPSCs, the proliferation and osteogenic differentiation potential of DPSCs were restored, and the activation of HMGA2/PI3K/Akt signalling was inhibited. In rat pulpitis models, the injection of let‐7c‐5p agomir restored the osteogenic differentiation potential of dental pulp cells and inhibited HMGA2/PI3K/Akt signalling. The findings demonstrated the anti‐inflammation and pro‐osteogenesis effect of let‐7c‐5p during the attack of pulpitis, which depended on the inhibition of HMGA2/PI3K/Akt signalling. [ABSTRACT FROM AUTHOR]

High incidence of articular cartilage defects resulting from age-related degeneration or trauma injuries is a major problem worldwide. Limited self-regeneration ability of cartilage often leads to inappropriate biochemistry and structure of healed tissue. Considering Impairments of traditional treatments, cell-based therapies are promising. The rapid ex vivo expansion and chondrogenic differentiation capability make dental pulp stem cells (DPSCs) a favorable cell type for therapeutic application, however strategies in order to efficient cartilage tissue-like production are imperative. In the present study the potential role of hypoxia mimicking agent, cobalt chloride (CoCl2), on chondrogenic differentiation of human DPSCs was surveyed. Cell viability assay used to obtain the optimum dose and exposure time of CoCl2. DPSCs were differentiated in pellet culture system after CoCl2 pretreatment. Chondrogenic differentiation efficiency was evaluated by histological and immunohistological analyses. The results showed that CoCl2 led to increased pellet size, integrity and matrix deposition with organizations more resembled typical cartilage lacuna structure. Furthermore, CoCl2 could improve differentiation by elevated chondrogenic markers, glycosaminoglycans (GAGs) and collagen II expression. CoCl2 pretreatment mitigated hypertrophy, as well, which was reflected in decreased collagen X expression. Alkaline phosphatase (ALP) specific activity did not change significantly by CoCl2 preconditioning. Based on current study hypoxia mimicking agent, CoCl2, could be suggested to promote DPSCs chondrogenic differentiation. [ABSTRACT FROM AUTHOR]

Rett syndrome is an X-linked neurodevelopmental disorder associated with psychomotor impairments, autonomic dysfunctions and autism. Patients with Rett syndrome have loss-of-function mutations in MECP2 , the gene encoding methyl-CpG-binding protein 2 (MeCP2). Abnormal biogenic amine signaling and mitochondrial function have been found in patients with Rett syndrome; however, few studies have analyzed the association between these factors. This study investigated the functional relationships between mitochondria and the neuronal differentiation of the MeCP2-deficient stem cells from the exfoliated deciduous teeth of a child with Rett syndrome. An enrolled subject in this study was a 5-year-old girl carrying a large deletion that included the methyl-CpG-binding domain, transcriptional repression domain, and nuclear localization signal of MECP2 . Using the single-cell isolation technique, we found that the two populations of MeCP2-expressing and MeCP2-deficient stem cells kept their MECP2 expression profiles throughout the stages of cell proliferation and neuronal differentiation in vitro . Neurite outgrowth and branching were attenuated in MeCP2-deficient dopaminergic neurons. MeCP2-deficient cells showed reduced mitochondrial membrane potential, ATP production, restricted mitochondrial distribution in neurites, and lower expression of a central mitochondrial fission factor, dynamin-related protein 1 than MeCP2-expressing cells. These data indicated that MeCP2-deficiency dysregulates the expression of mitochondrial factors required for the maturation of dopaminergic neurons. This study also provides insight into the pathogenic mechanism underlying dysfunction of the intracerebral dopaminergic signaling pathway in Rett syndrome. [ABSTRACT FROM AUTHOR]

In this study, we designed highly-aligned thermoplastic polycarbonate urethane (PCU) fibrous scaffolds coated with bioactive compounds, such as Poly- l -Lysine (PLL) and Poly- l -Ornithine (PLO), to enhance cellular adhesion and directivity. These products were characterized by scanning electron microscope (SEM) analysis which demonstrated that highly aligned fiber strands were formed without beads when coated onto a mandrel rotating at 1800 rpm. During in vitro cell test, PLO-coated, aligned PCU scaffolds were found to have significantly higher proliferation rates than PLL coated and bare PCU scaffolds. Interestingly, dental pulp stem cells (DPSCs) were observed to stretch along the longitudinal axis parallel to the cell direction on highly aligned scaffolds. These results clearly confirm that our strategy may suggest a useful paradigm by inducing neural tissue repair as a means to remodeling and healing of tissue for restorative procedures in neural tissue engineering. [ABSTRACT FROM AUTHOR]