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To study the effects of inducement on the expression of mouse embryonic stem cells SF1-G imprinted genes, Kcnq1 and Cd-kn1c during the course of differentiation into islet-like cells in vitro. Mouse embryonic fibroblasts (MEFs) were isolated from pregnant mice embryos and fibroblast feeder cells were prepared by treating 3-5th generations MEFs with Mitomycin C. Moreover, mouse embryonic stem cells were induced to differentiate into islet-like cells directly. RT-PCR and Immunofluorescence staining were used to test the expression of islet cell-specific markers. Cells were collected at various stages throughout the differentiation process and the imprinted genes Kcnq1 and Cdkn1c were tested by reverse transcription-polymerase chain reaction fragment length polymorphism (RT-PCR/RFLP). In the present study, we found that cells appear islet cell-specific gene expression. Furthermore, immunofluorescence shows us that the islet cell-specific hormone protein can be measured at stage, which confirms that the embryonic stem cells can be successfully induced into islet-like cells in vitro. RT-PCR/RFLP analysis showsthat imprinted genes Kcnq1 and Cdkn1c are biallelic expression in the differentiated cells, suggestive of loss of imprinting (LOI), while these genes demonstrate maternal monoallelic expression in the undifferentiated cells' continued subculture; this marks the maintenance of imprinting (MOI). Our data indicate that mouse embryonic stem cells are induced into islet-like cells in vitro. The gene imprinting status of Kcnq1 and Cdkn1c may be changed in differentiated cells during the induction in vitro. [ABSTRACT FROM AUTHOR]

Background: Literature data indicate that brain-derived neurotrophic factor (BDNF), cyclic-AMP response element-binding protein (CREB) and phospho-CREB (pCREB) may have a place in depression. BDNF belongs to the neurotrophin family that plays an important role in proliferation, survival and differentiation of different cell populations in the mammalian nervous system. The herbal mixture used in the present study consists of Euphoria longana, Houttuynia cordata and Dioscorea japonica. The purpose of the present study was to determine the neuroprotective effect of herbal mixture. We also tested the hypothesis that administration of herbs reverses memory deficits and promotes the protein expression of BDNF in the mouse brain. Methods: Mice were randomized into four different treatment groups (n = 10/group). Normal and stress groups received regular lab chow without stress and under stress conditions, respectively, for 3 weeks. The animals in the stress group were immobilized for 4 hours a day for 2 weeks. Different doses of herbal mixture (206 and 618 mg/kg) were administered for 3 weeks to those mice under stress conditions. Mice were analyzed by behavioral tests and immunoblotting examination in the hippocampus and cortex. An additional in vitro investigation was performed to examine whether herbs induce neurotoxicity in a human neuroblastoma cell line, SH-SY5Y cells. Results: No significant toxicity of herbs on human neuroblastoma cells was observed. These herbs demonstrated an inductive effect on the expression of BDNF, pCREB and pAkt. For spatial working memory test, herbal mixture fed mice exhibited an increased level of spontaneous alternation (p < 0.01) compared to those in stress conditions. Moreover, herbal mixture produced highly significant (p < 0.01) reduction in the immobility time in the tail suspension test. Mice in the herbal mixture groups demonstrated lower serum corticosterone concentration than mice in the stress group (p < 0.05). Effects of the oral administration of herbal mixture on protein levels of BDNF in the hippocampi and cortices were significant. Conclusions: Our study showed that herbal mixture administration has antidepressant effects in mice. It is proposed that adverse events such as stress and depression can modulate the expression of molecular players of cellular plasticity in the brain. [ABSTRACT FROM AUTHOR]

T regulatory (Treg) cells play crucial roles in the regulation of cellular immunity. The development of Treg cells depends on signals from TCRs and IL-2Rs and is influenced by a variety of transcription factors. The basic helix-loop-helix proteins are known to influence TCR signaling thresholds. Whether this property impacts Treg differentiation is not understood. In this study, we interrogated the role of basic helix-loop-helix proteins in the production of Treg cells using the CD4 promoter-driven Id1 transgene. We found that Treg cells continued to accumulate as Id1 transgenic mice aged, resulting in a significant increase in Treg cell counts in the thymus as well as in the periphery compared with wild-type controls. Data from mixed bone marrow assays suggest that Id1 acts intrinsically on developing Treg cells. We made a connection between Id1 expression and CD28 costimulatory signaling because Id1 transgene expression facilitated the formation of Treg precursors in CD28-/- mice and the in vitro differentiation of Treg cells on thymic dendritic cells despite the blockade of costimulation by anti-CD80/CD86. Id1 expression also allowed in vitro Treg differentiation without anti-CD28 costimulation, which was at least in part due to enhanced production of IL-2. Notably, with full strength of costimulatory signals, however, Id1 expression caused modest but significant suppression of Treg induction. Finally, we demonstrate that Id1 transgenic mice were less susceptible to the induction of experimental autoimmune encephalomyelitis, thus illustrating the impact of Id1-mediated augmentation of Treg cell levels on cellular immunity. [ABSTRACT FROM AUTHOR]