Project description:In this study, through three-dimensional spheroid culture, a group of unique multipotent stem cells were identified from mouse dental papilla, called multipotent dental pulp-regenerative stem cells (MDPSCs). MDPSCs exhibited enhanced osteo/odontogenic differentiation capabilities and could form regenerative dentin and neurovascular-like structures that mimicked the native teeth in vivo. Further analysis revealed that CD24a was the bona fide marker for MDPSCs and their expansion was highly dependent on the expression of a key transcriptional factor Sp7. Finally, CD24a positive cells could be detected in primary dental papilla in mice and human, suggesting MDPSCs resided in their native niches. Together, our study has identified a novel group of multipotent pulpregenerative stem cells with defined molecular markers for the potential treatment of pulpitis and pulp necrosis.
Project description:Throughout the various stages of tooth development, reciprocal epithelial-mesenchymal interactions are the driving force, for instance crucially involved in the differentiation of mature enamel-forming ameloblasts and dentin-producing odontoblasts. Here we established mouse tooth ‘assembloids’, comprised of tooth organoid-derived dental epithelial cells (from mouse molars and incisors) cultured together with molar dental pulp stem cells (DPSCs), to mimic these developmental interactions. Assembloids from both tooth types were grown both in basal- and differentiation-inducing conditions. Single cell transcriptomics analysis was applied to in detail characterize and validate the newly developed mouse tooth assembloid model and evaluate the induced differentiation processes.
Project description:Dental pulp regeneration is significantly aided by human dental pulp stem cells (hDPSCs). An increasing number of studies have demonstrated that circular RNAs (circRNAs) are crucial in the multidirectional differentiation of many mesenchymal stem cells, but their specific functions and mechanisms remain unknown. This work aimed at elucidating the molecular mechanism by which hsa_circ_0001599 works in hDPSCs during odontogenic differentiation. The expression of hsa_circ_0001599 in hDPSCs and dental pulp tissue was determined by using quantitative real-time PCR (qRT‒PCR). The role of hsa_circ_0001599 in the odontogenic differentiation of hDPSCs and its mechanism were studied using a variety of in vivo and in vitro assessments. The odontogenic differentiation of hDPSCs was facilitated by the overexpression of hsa_circ_0001599, which activated the PI3K/AKT signalling pathway in vitro. In vivo, hsa_circ_0001599 can promote the formation of new dentin-like structures. Mechanistically, hsa_circ_0001599 enhanced ITGA2 expression by sponging miR-889-3p. Furthermore, hsa_circ_0001599 interacts with the methylation reader hnRNPA2B1, promoting hnRNPA2B1 translocation from the nucleus to the cytoplasm and increasing ITGA2 mRNA stability. This research revealed the important role of hsa_circ_0001599 in odontogenic differentiation. Thus, hDPSCs engineered with hsa_circ_0001599 have the potential to be effective therapeutic targets for dental pulp repair and regeneration
Project description:Wnt regulates various cell responses. In dental pulp cells, Wnt signaling control cell proliferation, apoptosis, migration and differentiation. Here, the differential gene expression of human dental pulp stem cells treated with Wnt ligands or Wnt agonist was examined using a high throughput RNA sequencing technique. Results demonstrated that Wnt ligands or Wnt agonist altered numerous gene expression in human dental pulp stem cells.
Project description:Objectives: Sex hormone receptors are reported to be present in human dental pulp (HDP) cells. The purpose of this study was to examine the biological significance of estrogen and androgen receptors (ER and AR, respectively) in HDP cells. Design: We isolated HDP cells expressing ER- and AR-mRNAs and investigated the expression status of the receptors and the response to sex hormones in the cells. Results: HDP cells expressing ER- and/or AR-mRNAs had the ability to form alizarin red S-positive nodules in which calcium and phosphorus were deposited in vitro and to differentiate into odontoblasts-like cells and dentin-like tissue in vivo. Individual clones isolated from HDP cells exhibited a different expression pattern of mRNA for ER and AR. Some clones expressed ERM-NM-1- and/or ERM-NM-2-mRNAs and the others coexpressed ER- and AR-mRNAs. Using the Ingenuity software, we found that 17M-NM-2-estradiol (E2) and dihydrotestosterone (DHT) could act directly on HDP cells through ER- or androgen signaling-mediated mechanisms. E2 or DHT stimulated the mRNA expression for genes related to odontogenesis of dentin-containing teeth and odontoblast differentiation, suggesting that ER and AR in HDP cells may be involved in dentinogenesis. Conclusions: Our findings provide new insights into the biological significance of sex hormone receptors in HDP cells. Gene expression profiles of human dental pulp cells derived from one male patient were compared between cells treated with 10^-6 M 5alpha-dihydrotestosterone and cells treated with vehicle. Each sample has one replicate. Gene expression profiles of human dental pulp cells derived from one female patient were compared between cells treated with 10^-9 M 17beta-estradiol and cells treated with vehicle. Each sample has one replicate.
Project description:We have performed gene expression microarray analysis to profile transcriptomic signatures affected by EtOH in human dental pulp stem cells Established human dental pulp stem cells were treated with different dose of EtOH (0, 1, 5, 10, 20 and 50mM) for a different time periods (24 and 48 hrs). Total RNA was extracted and subjected to gene expression microarray analysis using Affymetrix human genome 2.0 plus array
Project description:Human mesenchymal stem cells are a promising cell source for the treatment of stroke. Their primary mechanism of action occurs via neuroprotective effects by trophic factors, anti-inflammatory effects, and immunomodulation. However, the regeneration of damaged neuronal networks by cell transplantation remains still challenging. We hypothesized that cells induced to neural lineages would fit the niche, replace the lesion, and be more effective in improving symptoms compared with stem cells themselves. We investigated the characteristics of induced neural cells from human dental pulp tissue and compared the transplantation effects between these induced neural cells and uninduced dental pulp stem cells. Induced neural cells or dental pulp stem cells were intracerebrally transplanted 5 days after cerebral infarction induced by permanent middle cerebral artery occlusion in immunodeficient mice. Effects on functional recovery were also assessed through behavior testing. We used immunohistochemistry and neuron tracing to analyze the differentiation, axonal extension, and connectivity of transplanted cells to the host’s neural circuit. Transplantation of induced neural cells from human dental pulp ameliorated functional recovery after cerebral infarction compared with dental pulp stem cells. The induced neural cells comprised both neurons and glia and expressed functional voltage, and they were more related to neurogenesis in terms of transcriptomics. Induced neural cells had a higher viability than did dental pulp stem cells in hypoxic culture. We showed that induced neural cells from dental pulp tissue offer a novel therapeutic approach for recovery after cerebral infarction.
Project description:Small molecules, BIO and Lithium chloride are widely used to activate Wnt signaling. It has been shown that these molecules induced beta-catenin accumulation and translocation, leading to the activation of Wnt signaling. These molecules also control various cell responses. Here, the differential gene expression of human dental pulp stem cells treated with BIO and Lithium chloride was examined using a high throughput RNA sequencing technique. Results demonstrated that BIO and Lithium chloride regulated the mRNA expression of various genes in human dental pulp stem cells.