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Objective. The transport and metabolism of glucose are important during mammalian development. High glucose can mediate the biological characteristics of mesenchymal stem cells (MSCs). However, the role of high glucose in the odonto/osteogenic differentiation of stem cells from apical papilla (SCAPs) is unclear. Materials and Methods. SCAPs were isolated and identified in vitro. Then, SCAPs were cultured in normal α-MEM and high glucose α-MEM separately. MTT assay was applied to observe the proliferation of SCAPs. ALP activity, alizarin red staining, real-time RT-PCR, and western blot were used to detect the odonto/osteogenic capacity of SCAPs as well as the participation of NF-κB pathway. Results. SCAPs in 25mmol/L glucose group expressed the maximum proteins of RUNX2 and ALP as compared with those in 5, 10, and 15 mmol/L groups. MTT assay showed that 25 mmol/L glucose suppressed the proliferation of SCAPs. ALP assay, alizarin red staining, real-time RT-PCR, and western blot showed 25 mmol/L high glucose can obviously enhance the odonto/osteogenic capacity of SCAPs. Moreover, the NF-κB pathway was activated in 25mmol/L glucose-treated SCAPs and the odonto/osteogenic differentiation was inhibited following the inhibition of NF-κB signaling pathway. Conclusions. High glucose can enhance the odonto/osteogenic capacity of SCAPs via NF-κB pathway. [ABSTRACT FROM AUTHOR]

This study aimed to investigate whether bone marrow-derived mesenchymal stem cells (BM-MSCs) can inhibit function of dendritic cells (DCs) by secreting Galectin-1 (Gal-1). BM-MSCs have been shown to inhibit the maturation and function of DCs, further inhibiting the activation and proliferation of T cells. However, the detailed mechanism remains unknown. In this current study, MSCs and DCs derived from mouse bone marrow were cocultured using Transwell culture plates under different in vitro conditions. The results showed that as the ratio of MSC to DC of the coculture system increased and the coculture time of the two cells prolonged, the concentrations of Gal-1, interleukin- (IL-) 10, and IL-12 in the supernatants were increased and the protein expression of Gal-1 on and within DCs was also enhanced. The phosphorylation of extracellular signal-regulated kinase (ERK) pathway in DCs was boosted, whereas p38 mitogen-activated protein kinase (MAPK) pathway phosphorylation was weakened. Meanwhile, the expression of costimulatory molecules on the surface of DCs was decreased, and the proliferative effect of DCs on allogeneic T cells was also decreased. Therefore, this present study indicated that Gal-1 secreted from MSCs upregulated expression of Gal-1 and stimulated formation of tolerance immunophenotype on DCs, where the underlying mechanism was the regulation of the MAPK signaling pathway in DCs, thereby inhibiting the function of DCs. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy (DN) is the leading cause of end stage renal disease worldwide. Increased glucose flux into the aldose reductase (AR) pathway during diabetes was reported to exert deleterious effects on the kidney. The objective of this study was to investigate the renoprotective effects of AR inhibition in high glucose milieu in vitro. Rat renal tubular (NRK-52E) cells were exposed to high glucose (30 mM) or normal glucose (5 mM) media for 24 to 48 hours with or without the AR inhibitor epalrestat (1 μM) and assessed for changes in Akt and ERK1/2 signaling, AR expression (using western blotting), and alterations in mitochondrial membrane potential (using JC-1 staining), cell viability (using MTT assay), and cell cycle. Exposure of NRK-52E cells to high glucose media caused acute activation of Akt and ERK pathways and depolarization of mitochondrial membrane at 24 hours. Prolonged high glucose exposure (for 48 hours) induced AR expression and G1 cell cycle arrest and decreased cell viability (84% compared to control) in NRK-52E cells. Coincubation of cells with epalrestat prevented the signaling changes and renal cell injury induced by high glucose. Thus, AR inhibition represents a potential therapeutic strategy to prevent DN. [ABSTRACT FROM AUTHOR]

Ovaries, which provide a place for follicular development and oocyte maturation, are important organs in female mammals. Follicular development is complicated physiological progress mediated by various regulatory factors including microRNAs (miRNAs). To demonstrate the role of miRNAs in follicular development, this study analyzed the expression patterns of miRNAs in granulosa cells through investigating three previous datasets generated by Illumina miRNA deep sequencing. Furthermore, via bioinformatic analyses, we dissected the associated functional networks of the observed significant miRNAs, in terms of interacting with signal pathways and transcription factors. During the growth and selection of dominant follicles, 15 dysregulated miRNAs and 139 associated pathways were screened out. In comparison of different styles of follicles, 7 commonly abundant miRNAs and 195 pathways, as well as 10 differentially expressed miRNAs and 117 pathways in dominant follicles in comparison with subordinate follicles, were collected. Furthermore, SMAD2 was identified as a hub factor in regulating follicular development. The regulation of miR-26a/b on smad2 messenger RNA has been further testified by real time PCR. In conclusion, we established functional networks which play critical roles in follicular development including pivotal miRNAs, pathways, and transcription factors, which contributed to the further investigation about miRNAs associated with mammalian follicular development. [ABSTRACT FROM AUTHOR]

MicroRNAs are a class of 18–22-nucleotide noncoding RNAs that posttranscriptionally regulate gene expression and have been shown to play an important role during myoblast differentiation. In this study, we found that the expression of miR-145a-5p was gradually increased during C2C12 myoblast differentiation, and miR-145a-5p inhibitors or mimics significantly suppressed or promoted the relative expression of specific myogenesis related marker genes. Moreover, overexpression or inhibition of miR-145a-5p enhanced or repressed the expression of some special genes involved in the endogenous Wnt signaling pathway during C2C12 myoblast differentiation, including Wnt5a, LRP5, Axin2, and β-catenin. These results indicated that miR-145a-5p might be considered as a new myogenic differentiation-associated microRNA that can promote C2C12 myoblast differentiation by enhancing genes related to myoblasts differentiation. [ABSTRACT FROM AUTHOR]

Intervertebral disc (IVD) degeneration is strongly associated with low back pain, a major cause of disability worldwide. An indepth understanding of IVD cell physiology is required for the design of novel regenerative therapies. Accordingly, aim of this work was the study of IVD cell responses to mitogenic growth factors in a three-dimensional (3D) organotypic milieu, comprising characteristic molecules of IVD's extracellular matrix. In particular, annulus fibrosus (AF) cells were cultured inside collagen type-I gels, while nucleus pulposus (NP) cells in chondroitin sulfate A (CSA) supplemented collagen gels, and the effects of Platelet-Derived Growth Factor (PDGF), basic Fibroblast Growth Factor (bFGF), and Insulin-Like Growth Factor-I (IGF-I) were assessed. All three growth factors stimulated DNA synthesis in both AF and NP 3D cell cultures, with potencies similar to those observed previously in monolayers. CSA supplementation inhibited basal DNA synthesis rates, without affecting the response to growth factors. ERK and Akt were found to be phosphorylated following growth factor stimulation. Blockade of these two signaling pathways using pharmacologic inhibitors significantly, though not completely, inhibited growth factor-induced DNA synthesis. The proposed culture systems may prove useful for further in vitro studies aiming at future interventions for IVD regeneration. [ABSTRACT FROM AUTHOR]

Oral mucosa is a useful material for regeneration therapy with the advantages of its accessibility and versatility regardless of age and gender. However, little is known about the molecular characteristics of oral mucosa. Here we report the first comparative profiles of the gene signatures of human oral mucosa fibroblasts (hOFs), human dermal fibroblasts (hDFs), and hOF-derived induced pluripotent stem cells (hOF-iPSCs), linking these with biological roles by functional annotation and pathway analyses. As a common feature of fibroblasts, both hOFs and hDFs expressed glycolipid metabolism-related genes at higher levels compared with hOF-iPSCs. Distinct characteristics of hOFs compared with hDFs included a high expression of glycoprotein genes, involved in signaling, extracellular matrix, membrane, and receptor proteins, besides a low expression of HOX genes, the hDFs-markers. The results of the pathway analyses indicated that tissue-reconstructive, proliferative, and signaling pathways are active, whereas senescence-related genes in p53 pathway are inactive in hOFs. Furthermore, more than half of hOF-specific genes were similarly expressed to those of hOF-iPSC genes and might be controlled by WNT signaling. Our findings demonstrated that hOFs have unique cellular characteristics in specificity and plasticity. These data may provide useful insight into application of oral fibroblasts for direct reprograming. [ABSTRACT FROM AUTHOR]